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Effect of biomass fuel exposure on infant respiratory health outcomes in Bangladesh

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Effect of biomass fuel exposure on infant respiratory health outcomes in Bangladesh

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Content Effect of Biomass Fuel Exposure on Infant Respiratory Health
Outcomes in Bangladesh
by
Lin Wang
A Thesis Presented to the
FACULTY OF THE KECK SCHOOL OF MEDICINE
UNIVERSITY OF SOUTHERN CALIFORNIA
In Partial Fulfillment of the
Requirements for the Degree
MASTER OF SCIENCE
(Applied Biostatistics and Epidemiology)
May 2021
Copyright 2021 Lin Wang
ii
Acknowledgements
I would like to convey my deepest appreciation to my master thesis committee: Dr. Talat
Islam, Dr. Meredith Franklin and Dr. Md. Towhid Salam for their supportive suggestions and
encouragement. Specially, I would like to express my deep gratitude to Dr. Islam, my thesis
supervisor, for his patient guidance and enthusiastic encouragement of this work.
Besides, I would like to thank Tasnia Ishaque for her assistance with data management.
Finally, I would express my thanks to everyone who has helped and supported me during
my graduate study, especially my family and my boyfriend.
iii
Table of Contents
Acknowledgements ....................................................................................................................................................... i i
List of Tables / Figures ................................................................................................................................................. iv
Abstract......................................................................................................................................................................... .v
Introduction ................................................................................................................................................................... 1
Methods ......................................................................................................................................................................... 3
Results ........................................................................................................................................................................... 9
Discussion.................................................................................................................................................................... 16
Conclusion ................................................................................................................................................................... 20
References ................................................................................................................................................................... 21
iv

List of Tables / Figures
Figure 1. Participant flow in the study ........................................................................................................................... 4
Table 1. Socio-demographic characteristics of the study population according to fuel type ....................................... 10
Table 2. Maternal and child’s demographic characteristics according to fuel type ..................................................... 11
Table 3. Infant respiratory outcomes according to fuel type ....................................................................................... 12
Table 4. Unadjusted association of potential confounders with infant respiratory outcomes ...................................... 14
Table 5. Adjusted association of fuel type with infant respiratory outcomes .............................................................. 15

v

Abstract
Background: Exposure to biomass fuel use is associated with a higher risk of respiratory
outcomes among children under 5 years of age, but little evidence exists about the effects of
different biomass fuel types on respiratory health outcomes or the age of onset among infants.
This study aims to evaluate whether compared to liquid petroleum gas (LPG)/electricity, the use
of wood, cow dung, and crop residue for cooking is associated with 1) respiratory health
outcomes in infants and 2) age of onset of respiratory ailments in a Bangladeshi pregnancy
cohort.
Methods: From 2016 to 2017, we recruited 903 pregnant women within confirmed 18 weeks of
gestation and followed them at study entry, birth, and every 3 months during the first year after
delivery (2017-2019). We collected data on household characteristics, socio-demographics, and
respiratory health outcomes of infants. Multivariate analyses were conducted using fuel type as
the exposure variable of interest, adjusting for identified confounders. For binary respiratory
outcomes we used logistic regression, for categorical outcomes we used multinomial regression,
and for continuous respiratory outcomes we used linear regression.
Results: About 55% households used wood (n=442) as primary fuel for cooking, while 27%
used crop residues (n=215), 12% used cow dung, and only 6% used LP gas or electricity.
Adjusted mean age of wheeze onset in infants was 101 days, and it was significantly (p<0.05)
earlier in households using cow dung (75 days), wood (76 days), and crop residues (77 days).
The odds of developing fever in the first three months of life were more than 2-fold higher
among infants from households using cow dung (OR: 2.49, 95% CI: 1.16-5.44) and crop residues
(OR: 2.42, 95% CI: 1.19-4.95) compared to infants from households using LP gas or electricity.
In addition, in multivariate analysis, we found that female infants had significant lower risk of
vi

fever and cough in the first 3 months of life (OR: 0.64, 95% CI: 0.47-0.85 for fever and OR:
0.66, 95% CI: 0.49-0.88 for cough) compared with male infants.
Conclusion: Prenatal exposure to biomass fuel, especially cow dung and crop residues, puts
infants at higher risk for developing wheeze earlier and having fever in the first three months of
life. Interventions to reduce exposure to biomass fuel combustion during pregnancy will reduce
burden of illness in infants and promote children’s health in developing nation like Bangladesh.
Keywords: age of onset, Bangladesh, biomass fuel, crop residue, cough, fever, infant respiratory
outcomes, wheeze.

1

Introduction
Nearly three billion people worldwide, primarily from developing countries, are exposed
to air pollution from biomass fuels (WHO, 2018). Biomass fuel refers to burned plant or animal
material, including wood, crop residues, and animal dung (Smith et al., 2004). The use of these
unprocessed fuels for cooking and heating accounts for more than 95% of domestic energy in
lower income countries and is likely to be the largest source of household air pollution on a
global scale (Smith et al., 2004).
Biomass fuels in the developing countries are usually used in traditional cook stoves with
limited air supply leading to incomplete combustion (Balmes, 2019). The smoke due to
incomplete combustion of biomass fuels consists of particulate matters (PM10: with an
aerodynamic diameter 10 microns or less, PM2.5: with an aerodynamic diameter 2.5 microns or
less), NOx, CO and different toxic compounds like unburned hydrocarbons, SOx, Cl compounds,
and particulate metal aerosols (Williams et al., 2012). Studies have noted very high level of
PM2.5 in households using biomass fuel compared to cleaner fuel such as liquid pressurized gas
(LPG) during cooking activities (Bates et al., 2018; Kabera et al., 2020). While the 24-hour mean
of ambient PM2.5 above 25µ g/m
3
is regarded as unhealthy according to WHO (WHO, 2006b).
PM2.5 levels in households using biomass fuel has been observed to be at least a magnitude
greater than those levels. Pokhrel et al. reported an annual mean PM2.5 levels in households
kitchen were 656µ g/m
3
from biomass, while it was 101µ g/m
3
in kitchens using LPG and
80µ g/m
3
in kitchens using electricity (Pokhrel et al., 2015). The kitchen levels of PM2.5 also has
been observed to differ by type of biomass fuel used for cooking (Bartington et al., 2017). The
average PM2.5 concentrations during cooking period was 520µ g/m
3
for wood, 1179.4µ g/m
3
for
dung, and 1037.2µ g/m
3
for mixed fuel (wood, dung, and straw) (Bartington et al., 2017).
2

Additionally, another study further suggested that the use of dung based fuel produced more
organic toxicants in addition to higher levels of PM2.5 compared to wood irrespective of the stove
types (Jayarathne et al., 2018).
There is a growing body of evidence that indicates that exposure to higher level of PM2.5
is associated with increased risk of respiratory infections in infants and low-birth-weight (Bates
et al., 2018; Li et al., 2019). Biomass fuel has also been associated with acute lower respiratory
infections (ALRIs), pneumonia, low birth weight (LBW), and all-cause mortality in infants
(Tielsch et al., 2009). According to WHO report, pneumonia is one of the leading causes of death
in young children, and 45% of all pneumonia-related deaths in children under 5 years of age are
caused by household air pollution or HAP (WHO, 2018). Cooking with biomass fuels has been
reported to be a significant risk factor of acute respiratory infection (ARI) (Admasie et al., 2018).
A case-control study conducted in Nepal reported that 2-35 months old children from households
using biomass fuel had a 1.93 times greater risk of ALRI compared to those from households
using electricity (Bates Michael N. et al., 2013). Moreover, a case-control study in India reported
nearly 4-fold greater risk of pneumonia in infants and young children was associated with solid
fuel use compared to infants in households without using any type of fuel from wood, coal, and
cow dung (Mahalanabis et al., 2002). Besides possible effect of different types of biomass fuel
on respiratory health outcomes among infants, biomass fuel use might be associated with early
onset of respiratory infection that can increase severity of infant pneumonia. Infants aged 28
days to 6 months has been reported to have a 5.5-fold higher risk of dying from pneumonia
compared to children aged 12 to 59 months (Ferdous et al., 2018). A study from rural Indonesia
reported that infants less than 4 months hospitalized with pneumonia were 5.6 times more likely
to die compared to older children (Djelantik et al., 2003). The earlier age of pneumonia has been
3

associated with exposure to higher levels of PM2.5 (Gurley et al., 2014). Gurley et.al. reported
that each hours of exposure to PM2.5 levels above 100 µ g/m
3
was associated with 12% decrease
in age of onset of pneumonia (Gurley et al., 2014). Given that the burning of biomass fuel,
especially dung fuel, contributes to higher indoor PM2.5 levels than other fuel types, the effects of
type-specific biomass fuel on the onset of pneumonia needs to be investigated.
Currently, limited data are available regarding the effects of different types of biomass
fuel on infant respiratory health outcomes and their effect on age of onset of ALRI. In the current
study, we wanted to address these existing research gaps in a pregnancy cohort of 807 mother-
infant pairs from Bangladesh. In Bangladesh, biomass fuel accounts for approximately 70% of
the total energy consumption and 88% population are exposed to air pollution due to the burning
of biomass fuels (Haider et al., 2016; Masud et al., 2019). Wood fuels, crop residues, and cow
dung were identified as the most preferred biomass fuel used for the majority of the rural
population of Bangladesh (Jashimuddin et al., 2006). Furthermore, pneumonia is the second
leading cause of infant mortality in Bangladesh. The objective of the current study was to
evaluate whether compared to LPG/electricity, the use of wood, cow dung, and crop residue for
cooking is associated with 1) respiratory health outcomes in infants and 2) age of onset of
respiratory ailments.
Methods
Study population
From 2016 to 2017, we recruited 903 pregnant women and established a pregnancy
cohort from Chirirbandar and Syedpur in Bangladesh. The population of Chirirbandar is
primarily rural, while Syedpur consists of a rural and semi-urban mix. The total population and
4

number of households in Chirirbandar were 283,817 and 66,438, and 264,246 and 58,137 in
Syedpur, respectively. For recruiting the study population, each of the trained study field workers
(SHW, N=10) related to 15-20 village health workers (VHW) who were involved in child and
maternal health care in the local communities. The VHWs regularly visited all households under
her responsibility and identified newly pregnant women based on menstrual history or physician
diagnosis. The SHWs then visited the identified women and informed them of the details of the
study. Both women and their husbands gave verbal and written consent. Of the 991 pregnancies
identified, 53 women refused to participate in the study. Women were enrolled within 18 weeks
of gestation and gestational age was verified by ultrasonogram. We excluded 35 pregnant women
as the gestational age was assessed to be 19 weeks or more based on ultrasound.
Among 903 identified pregnant women, some were excluded due to miscarriage (n=50)
or had still births (n=16). Of the 837 live births, 30 infants were excluded due to the exposure not
being of interest (n=3) or were lost to follow up (n=27) from birth to visit at 9 months of age.
The final sample size for this investigation included 807 infants (Figure 1).

Figure 1. Participant Flow in the Study

5

The trained SHWs conducted in-person interviews of the mothers at study entry, every
trimester after study entry, within 72-hours of childbirth, and every 3 months during the first year
after delivery (2017 to 2019). The data used in this study are from the baseline questionnaire at
study entry, birth visit, and visit at 3 months of age, 6 months of age, and 9 months of age,
respectively. The baseline questionnaire collected information on maternal and household
characteristics including maternal age, history of chewing tobacco, residence, Wealth Index,
location of the kitchen, and fuel type used for cooking. Children characteristics such as birthday,
sex, and birthweight were obtained from the birth visit. Infant respiratory health outcomes and
breastfeeding practices were collected from 3
rd
, 6
th
, and 9
th
months follow-up surveys. The age of
each infant was calculated based on the date of interview and birthday.
Exposure assessment
The primary exposure of interest in this study was fuel type used for household cooking
during pregnancy. Each participant was asked “What fuels do you primarily use for cooking?” at
study entry. The questionnaire offered eleven options from which mothers could select the fuel
they cooked with, and additional “other” fuel types than those eleven types were also recorded.
The eleven responses included LPG, kerosene, coal, wood, hay/leaves/grass, residues of
agriculture, cow dung, jute, electricity, biogas, and natural gas and multiple responses were
encouraged. However, the mix use of different types of fuel existed, so we determined to use the
main fuel they reported as the fuel type investigated in this study. We then explored the
distribution of the primary fuel used for cooking in each household. Based on the responses and
distributions of fuel type used for cooking, LPG and electricity were considered as clean fuel,
wood and cow dung were specified as a single category, and hay/leaves/grass, jute, agriculture
residues were classified into ‘crop residues’. As only three participants used kerosene oil for
6

cooking, those were excluded from the analysis (N=807). Hence, fuel types were categorized
into four categories: LPG/electricity, cow dung, wood, and crop residues.
The mothers also provided information regarding the location of the kitchen, which in the
questionnaire had four options: inside living space/bedroom, separate kitchen inside the house,
separate kitchen inside the boundary, and outside. Responses beyond these answers were also
noted. According to the answer, the kitchen location was defined as a binary variable: inside the
home vs outside the home, regardless of the cooking fuel type. Kitchen inside home included
kitchens located inside bedroom or separate place within the households. Whereas kitchen
outside could be within the house boundary or in any open places outside the house.
Respiratory outcome
The infant respiratory outcomes examined in this study were: ever wheeze, age of wheeze
onset, wheeze frequency in first three months, cough in first three months, and fever in first three
months. At each visit, mothers were asked about the presence of wheezing or whistling in the
chest, cough, and fever in infants. If the mothers reported children having wheeze prior to the
interview, they were asked regarding the age of the infant at the time of first wheeze and
frequencies of wheeze or breathing difficulty since birth.
We defined the respiratory outcomes in the infants by two different time points: by 9
months of age, and in the first 3 months after birth. Ever wheeze was defined as any reported
incidence of wheeze by 9 months of age. We defined cough and fever in first 3 months as any
reported occurrence of cough or fever by 3 months of age.
The age of wheeze onset was determined based on the infants’ age at the time of the first
wheeze as reported by the mother at the 3
rd
, 6
th
, or 9
th
month visit. If the mother reported that
their infant had wheezed, they were asked to state when the first episode was given the following
7

choices (based on the follow-up visit) — in the first month, 1-2 months, 2-3 months, 4+ months,
6-9 months, and 9+ months. We defined age at onset of wheeze as the first time when infants had
wheezed, and we used the middle of each time period as the age of onset. For example, the age
of onset for infants who had wheeze in the first months of life were given 15 days, while those
who had wheeze 9 months as 270 days.
To capture the severity of wheeze, we created a three-level nominal variable for the
wheeze frequency in first three months: no wheeze in the first 3-months, one incidence of
wheeze in the first 3-months and 2 or more incidences of wheeze in the first 3-months.
Other variables
We considered the following covariates to describe the study population: maternal age
(<18 and ≥18, in years), maternal chewing tobacco history (yes, no), exclusive breastfeeding (by
6 months), and child information, including sex (male, female) and birth weight (≥2.5kg and
<2.5kg).
Maternal age was collected at the study entry. Given that the ages ranged from 14-40, we
dichotomized it as <18 and ≥18 years. Maternal chewing tobacco history was collected at the
baseline survey; mothers were asked if they used any type of chewing tobacco — gul, khaini,
tobacco leaf, paan masala or zarda — during the pregnancy. If a mother stated that she used any
type of chewing tobacco, then she was defined as using chewing tobacco. Details regarding
breastfeeding practices were also available from the mothers. Mothers reported when they started
giving breast milk as well as other foods. All the infants were breastfed immediately after birth.
We defined exclusive breastfeeding as not giving other foods besides breast milk before 6
months of age. Sex of the child and their birth weight were recorded at birth. We considered
weighing less than 2.5kg as low birthweight.
8
We created Wealth Index separately for rural or semi-urban residences based on
productive assets (land ownership, livestock, poultry, etc.), non-productive assets (own home,
refrigerator, TV, bicycle, motorbike), and household utilities and others (water source, toilet
type, wall type, flooring, persons in household, job type of mother and father, education level of
mother and father) using principal component analysis (“Creation of a Wealth Index, June 2017 |
World Food Programme,” 2017). It measured relative wealth and was divided into five equally
distributed groups.
Statistical analysis
We initially explored the distribution of different pertinent sociodemographic factors,
maternal and infant characteristics, and infant respiratory outcomes by fuel type. To examine the
association between fuel type and each explanatory variable, Pearson’s chi-squared tests were
performed for categorical variables and student’s t-tests were used for continuous variables.
We conducted bivariate analyses with each outcome to identify potential confounders
where statistically significant or marginally significant variables were retained for the
multivariate analyses. Multivariate analyses using fuel type as the exposure variable of interest
were then adjusted using the identified confounders. For binary respiratory outcomes we used
logistic regression (ever wheeze, cough in first three months, and fever in first three months), for
the categorical outcome (wheeze frequency in the first three months) we used multinomial
regression, and for the continuous respiratory outcome (age at first wheeze) we used linear
regression.
The identified confounders used in the adjusted multivariate models included Wealth
Index, maternal age, maternal chewing tobacco, and infant sex. We checked interactions between
9

infant sex, maternal age, and maternal chewing tobacco for the infant respiratory outcomes
individually and they were non-significant. The results are presented as odds ratios for binary
and categorical outcomes and as effect estimates (beta coefficients) for continuous outcome
variables, all with 95% confidence intervals. Overall, statistical significance was set at α = 0.05
testing two-sided hypotheses. Data management and statistical analysis were performed using R
version 4.0.3 (R Core Team, Vienna, Austria, 2020, https://www.R-project.org/).
Results
Of the 807 women in the current study, 40.1% resided in Chirirbandar and 59.9% in
Syedpur (Table 1). About 55% households used wood (n=442) as primary fuel for cooking,
while 27% used crop residues (n=215), 12% used cow dung, and only 6% used LPG or
electricity. In 41.5% households the kitchen was located outside. The type of fuel used for
cooking significantly differed by residence, wealth index, and kitchen location (p-value: <0.001).
The vast majority of LPG or electricity use (86%) were in Syedpur households, while in
Chirirbandar more than half of the households used other fuel types. None in the lowest two
Wealth Index groups used LPG or electricity and 78% users of LPG or electricity were from the
highest Wealth Index quintile. Outside kitchens were more common in households using cow
dung, wood, and crop residues; only 10% users of LPG or electricity cooked in outside kitchen.
The mean (SD) age of the mothers in the study was 22.3(4.4) years (Table 2), about 9%
used chewing tobacco during pregnancy, and 19.5% breastfed their child exclusively by 6
months. Of the 807 infants in the study 51.9% were male, and28.6% had low birthweight.
Mothers’ age varied by household fuel type use (p-value: <0.001) with the mean age of 25.1
10

years among LPG or electricity users while mean age ranged between 22.0-22.4 years for
biomass fuel users.

Table 1. Socio-demographic characteristics of the study population according to fuel type
Characteristics
††

LPG/
Electricity
Cow dung Wood Crop residues Total
(N=50) (N=100) (N=442) (N=215) (N=807)
Wealth index
‡

0 0 (0%) 20 (20.0%) 83 (18.8%) 57 (26.5%) 160 (19.8%)
1 0 (0%) 26 (26.0%) 85 (19.2%) 43 (20.0%) 154 (19.1%)
2 4 (8.0%) 20 (20.0%) 94 (21.3%) 48 (22.3%) 166 (20.6%)
3 7 (14.0%) 20 (20.0%) 96 (21.7%) 46 (21.4%) 169 (20.9%)
4 39 (78.0%) 14 (14.0%) 84 (19.0%) 21 (9.8%) 158 (19.6%)
Residence
‡

Chirirbandar 7 (14.0%) 78 (78.0%) 237 (53.6%) 161 (74.9%) 483 (59.9%)
Syedpur 43 (86.0%) 22 (22.0%) 205 (46.4%) 54 (25.1%) 324 (40.1%)
Kitchen Location
‡

Inside 45 (90.0%) 57 (57.0%) 278 (62.9%) 92 (42.8%) 472 (58.5%)
Outside 5 (10.0%) 43 (43.0%) 164 (37.1%) 123 (57.2%) 335 (41.5%)
††
Chi-square test was used to compare the groups for categorical variables.
‘
‡
’ p-value < 0.001

During the 9 months follow-up, 60% of the infants developed wheeze (Table 3), while
14% infants had one wheeze and 8.6% infants had two or more wheeze in the first three months.
Nearly 46.5% infants had cough and 57.5% had fever by first three months of life. The mean
(SD) age in the first age of wheeze onset was 82 (56). The mean age of wheeze onset differed by
the type of cooking fuel used in households (p-value: <0.001). The mean age of wheeze onset
among LPG or electricity users was 113 while it ranged from 80-81 days for biomass fuel users.
About 44% infants from households who used LPG or electricity had fever in first three months,
while the proportions of having fever was higher (54.1% to 65.1%) for different types of biomass
fuel users.
11
Table 2. Maternal and child’s demographic characteristics according to fuel type
Characteristics
††

LPG /
Electricity
Cow dung Wood Crop residues Total
(N=50) (N=100) (N=442) (N=215) (N=807)
Maternal
Maternal age (mean, SD)
‡
25.1 (4.40) 22.4 (4.36) 22.2 (4.37) 22.0 (4.28) 22.3 (4.40)
Maternal chewing tobacco use
Yes 5 (10.0%) 9 (9.0%) 42 (9.5%) 20 (9.3%) 76 (9.4%)
Exclusive breastfeeding
Yes 8 (16.0%) 19 (19.0%) 86 (19.5%) 44 (20.5%) 157 (19.5%)
Child
Sex
Male 24 (48.0%) 51 (51.0%) 229 (51.8%) 115 (53.5%) 419 (51.9%)
Low birth weight (< 2.5kg)
No 33 (66.0%) 74 (74.0%) 302 (68.3%) 145 (67.4%) 554 (68.6%)
Yes 15 (30.0%) 25 (25.0%) 126 (28.5%) 65 (30.2%) 231 (28.6%)
Missing 2 (4.0%) 1 (1.0%) 14 (3.2%) 5 (2.3%) 22 (2.7%)
††
Student’s t-test was performed to compare the groups for continuous variable; chi-square test was conducted for
categorical variables.
‘
‡
’ p-value < 0.001
Infants living in families with the highest Wealth Index quintile resulted in having first
wheeze 17 (95% CI: 1-33) days later compared to those with the lowest Wealth Index group
(Table 4). Infants from mothers who is under 18 years of age was significantly associated with
having wheeze 20 (95% CI: -39-0) days earlier as compared to those from older mother. Relative
to mothers who are more than 18 years of age, having a younger mother increased the likelihood
of an infant having one wheeze episode (OR: 2.21, 95% CI: 1.15-4.25) and cough (OR: 1.90,
95% CI: 1.08-3.42) in the first three months. Maternal chewing tobacco nearly doubled the risk
of developing wheeze in infants from birth to 9 months (OR: 1.98, 95% CI: 1.18-3.45). We also
observed the risk of having cough (OR: 0.64, 95% CI: 0.48-0.85) and fever (OR: 0.62, 95% CI:
0.46-0.83) in the first three months was almost 40% lower among female infants in comparison
to male infants. In fully adjusted model, the gender-specific difference in ORs remained
12

statistically significant (OR: 0.64, 95% CI: 0.47-0.85 for fever and OR: 0.66, 95% CI: 0.49-0.88
for cough).

Table 3. Infant respiratory outcomes according to fuel type
Respiratory Outcomes
††

LPG /
Electricity
Cow dung Wood Crop residues Total
(N=50) (N=100) (N=442) (N=215) (N=807)
Ever wheeze.
No 21 (42.0%) 37 (37.0%) 193 (43.7%) 72 (33.5%) 323 (40.0%)
Yes 29 (58.0%) 63 (63.0%) 249 (56.3%) 143 (66.5%) 484 (60.0%)
Wheeze frequency in first 3 months
0 39 (78.0%) 69 (69.0%) 339 (76.7%) 145 (67.4%) 592 (73.4%)
1 6 (12.0%) 16 (16.0%) 53 (12.0%) 40 (18.6%) 115 (14.3%)
2+ 2 (4.0%) 9 (9.0%) 35 (7.9%) 23 (10.7%) 69 (8.6%)
Missing
§
3 (6.0%) 6 (6.0%) 15 (3.4%) 7 (3.3%) 31 (3.8%)
Age of wheeze onset (in days) ‡
Mean (SD) 113 (71) 81 (62) 81 (52) 80 (55) 83 (56)
Cough in first 3 months*
No 24 (48.0%) 46 (46.0%) 239 (54.1%) 92 (42.8%) 401 (49.7%)
Yes 23 (46.0%) 48 (48.0%) 188 (42.5%) 116 (54.0%) 375 (46.5%)
Missing
§
3 (6.0%) 6 (6.0%) 15 (3.4%) 7 (3.3%) 31 (3.8%)
Fever in first 3 months†
No 25 (50.0%) 31 (31.0%) 188 (42.5%) 68 (31.6%) 312 (38.7%)
Yes 22 (44.0%) 63 (63.0%) 239 (54.1%) 140 (65.1%) 464 (57.5%)
Missing
§
3 (6.0%) 6 (6.0%) 15 (3.4%) 7 (3.3%) 31 (3.8%)
††
Student’s t-test was performed to compare the groups for continuous variable; chi-square test was conducted for
categorical variables.
§
Missing were those who did not participate in first 3 months.
P-value: ‘‡’ < 0.001 ‘†’ < 0.01 ‘*’ < 0.05

We then explored the effect of cooking fuel use on respiratory health outcomes after
adjusting for Wealth Index, maternal age, maternal chewing tobacco, and infant sex. After
adjusting for potential confounders, the age of wheeze onset significantly differed by household
fuel type use (p-value: <0.001, Table 5). The adjusted mean age of wheeze onset was 101 days
while it was significantly earlier in households using cow dung (mean age: 75 days), wood
(mean age: 76 days), and crop residues (mean age: 77 days). We also observed the risk of having
13
two or more wheeze attacks in the first three months of life among biomass fuel users was more
than twice as compared to LPG or electricity users, however, none of these associations were
statistically significant. In comparison to infants from households using LPG or electricity for
cooking, the odds of developing fever in the first three months of life were more than 2-fold
increased among infants from households using cow dung (OR: 2.49, 95% CI: 1.16-5.44) and
crop residues (OR: 2.42, 95% CI: 1.19-4.95).
14
Table 4. Unadjusted association of potential confounders with infant respiratory outcomes
Characteristics
Ever wheeze

Age of wheeze onset
(in days)
Having one wheeze
attack in first 3
months

Having two or more
wheeze attacks in
first 3 months
Cough in first 3
months

Fever in first 3
months
OR (95% CI)
*
Estimate (95% CI)
†
OR (95% CI)
§
OR (95% CI)
§
OR (95% CI)
*
OR (95% CI)
*
Wealth index
0 Ref 77 (65, 88) †† Ref Ref Ref Ref
1 1.13 (0.72-1.76) 3 (-13, 19) 1.48 (0.79-2.77) 1.54 (0.70-3.40) 0.81 (0.51-1.27) 0.63 (0.40-1.01)
2 1.41 (0.90-2.21) -2 (-17, 14) 1.17 (0.62-2.22) 1.71 (0.80-3.65) 0.82 (0.52-1.27) 0.67 (0.42-1.06)
3 1.10 (0.71-1.70) 13 (-3, 29) 0.92 (0.48-1.76) 0.69 (0.28-1.69) 0.95 (0.61-1.47) 0.84 (0.53-1.34)
4 1.08 (0.69-1.69) 17 (1, 33) ‡ 1.09 (0.57-2.09) 1.04 (0.45-2.42) 0.77 (0.49-1.20) 0.70 (0.44-1.12)
Maternal age
≥18 Ref 84 (79, 89) †† Ref Ref Ref Ref
<18 0.99 (0.57-1.73) -20 (-39, 0) ‡ 2.21 (1.15-4.25) ‡ 1.24 (0.47-3.29) 1.90 (1.08-3.42) ‡ 1.65 (0.92-3.09)
Maternal chewing
tobacco use
No Ref 84 (79, 89) †† Ref Ref Ref Ref
Yes 1.98 (1.18-3.45) ‡ -8 (-24, 7) 1.16 (0.60-2.25) 1.69 (0.82-3.49) 1.14 (0.71-1.84) 1.17 (0.72-1.93)
Infant sex
Male Ref 79 (72, 86) †† Ref Ref Ref Ref
Female 0.91 (0.68-1.20) 8 (-2, 18) 0.97 (0.65-1.44) 0.62 (0.37-1.03) 0.64 (0.48-0.85)
**
0.62 (0.46-0.83)
**

*
Odds ratio (OR) and 95% confidence interval (CI) are based on binary logistic regression models.
†
Mean age of wheeze onset and its 95% CI are from linear regression models.
§
Multinomial logistic regression model was conducted to analyze the association between covariates and wheeze frequency in first 3 months.
P-value: ‘††’ < 0.001, ‘‡’ < 0.05, ‘**’ < 0.01
15
Table 5. Adjusted association of fuel type with infant respiratory outcomes
Characteristics**
Ever wheeze
Age of wheeze onset (in
days)
Having one
wheeze attack in
first 3 months
Having two or more
wheeze attacks in
first 3 months
Cough in first 3
months
Fever in first 3
months
OR (95% CI)
§
Estimate (95% CI)
††
OR (95% CI)
ǁ
OR (95% CI)
ǁ
OR (95% CI)
§
OR (95% CI)
§

Fuel type
LPG / Electricity Ref 101 (75, 127) ‡ Ref Ref Ref Ref
Cow dung 1.28 (0.60-2.70) -26 (-52, 0)* 1.51 (0.51-4.47) 2.51 (0.48-13.14) 0.98 (0.46-2.08) 2.49 (1.16-5.44)*
Wood 0.96 (0.50-1.81) -25 (-48, -2)* 1.00 (0.38-2.64) 2.00 (0.44-9.22) 1.13 (0.56-2.27) 1.50 (0.78-2.92)
Crop residues 1.50 (0.75-3.00) -24 (-49, 0)* 1.78 (0.65-4.89) 3.08 (0.64-14.79) 0.72 (0.37-1.39) 2.42 (1.19-4.95)*
**
All modes were adjusted for maternal age, wealth index, maternal chewing tobacco, and infant sex.
§
Odds ratios (OR) and 95% confidence interval (CI) are from multivariable

logistic regression.
††
Mean age of wheeze onset and its 95%CI is from multivariable linear regression models.
ǁ
Multinomial logistic regression model was used to evaluate the association between exposures and wheeze frequency in first 3 months.
p-value: ‘‡’ < 0.001 ‘*’ < 0.05
16
Discussion
We found that onset of wheeze was on average 25 days earlier in infants from households
using biomass fuel for cooking compared to infants from households using LPG/electricity.
Furthermore, infants of mothers who used cow dung or crop residues for cooking were more than
twice as likely to have fever in the first three months than those used LPG or electricity. Overall,
these data provide evidence that of the three types of biomass fuel, cow dung and crop residues
tended to be more detrimental to infant respiratory health.
Although there is no direct evidence on the effect of biomass fuel exposure on age of
wheeze onset among infants, higher levels of household PM2.5 has been reported to be associated
with earlier age of ALRI in children (Gurley et al., 2014). Gurley at al. reported each hour that
PM2.5 levels above 100 µ g/m
3
was independently associated with a 12% decrease in age of first
ALRI among infants under 2 years of age (Gurley et al., 2014). Like their findings, we found that
using biomass fuel for cooking could decrease the age for 25 days on average at which children
experience their first wheeze, comparing to LPG/electricity users. The higher PM2.5
concentrations from burning of biomass fuels rather than those from LPG/electricity may
reasonably explain this finding, a study assessed PM2.5 levels from four different cooking fuels in
Nepal provided further evidence: compared with electric stoves, use of LPG, kerosene and
biomass stoves had increased indoor PM2.5 concentrations by 65%, 146%, and 733%,
respectively (Pokhrel et al., 2015). Besides biomass fuel use, we also observed that infants from
low socioeconomic status and whose mothers were young at childbirth (<18 years of age) were
more likely to have earlier age of wheeze onset. There are some previous studies supporting
these findings. For instance, a cohort study of respiratory illness during the first year of life
17
found that infants with the high socioeconomic status had 0.67 incidence of respiratory outcomes
while those with the low socioeconomic status was 1.41 (Margolis et al., 1992). Martinez et al.
reported that 2.4 and 1.8 increased risk in wheezing lower respiratory tract illnesses among
infants whose mothers were less than 21 years of age and were aged 26 to 30 when compared
with those aged more than 30 years (Martinez et al., 1992).
We also found children in households that used cow dung and crop residues had a higher
risk of reporting fever in the first three months of life than infants from households using LPG or
electricity. Although fever has not been shown to be a necessary indicator of ALRI, it is
indicative of the possibility of pneumonia (Cardoso et al., 2011). Thus, this finding suggests that
exposure to biomass fuel such as cow dung and crop residues may increase the risk of
pneumonia in infants at early age. We also observed that female infants had a significantly lower
risk of having fever and cough in the first three months compared to males. This result is
different from the earlier findings. For example, a sex-stratified analyses suggested that girls
were particularly vulnerable due to increased respiratory rate at 30 days of age, which was
associated with increased risk for physician-assessed pneumonia (RR: 1.02) and severe
pneumonia (RR: 1.04) in the first year of life (Lee et al., 2018). However, a study examined on
sex differences in the severity of respiratory outcomes reported that males seems to develop
respiratory tract infections more frequently than females, and the sex-specific differences may
result from the regulation by sex hormones (Falagas et al., 2007). This observation of gender
difference in fever prevalence in our study is likely due to higher susceptibility of infectious
disease in male infants (Muenchhoff & Goulder, 2014). Girls have been found to mount more
vigorous cellular and humoral immunity than boys (Fish, 2008). Healthy infants have postnatal
activation of hypothalamic-pituitary-gonadal axis from first month to 3 months of life where
18

levels of FSH and estradiol is higher in girls and levels of LH and testosterone is higher among
boys. While the LH and testosterone levels decrease after 3 months, levels of estradiol and FSH
remains elevated longer, thus likely imparting stronger immune responses in girls than boys
(Johannsen et al., 2018).
We did not detect any statistically significant association between ever wheeze, wheeze
frequency and cough in first three months and fuel type used for cooking; however, biomass fuel
use was associated with detrimental respiratory health outcomes compared to LPG/electricity
users. A possible explanation for these weak associations may be the small sample size in LPG
or electricity group (n=50), and in this group, only 6 infants had one episode of wheeze and 2
infants had two or more episodes of wheeze in the first three months of age. Another interesting
factor that was found to be significantly associated with ever wheeze was maternal chewing
tobacco during pregnancy, which nearly doubled the risk of wheezing in infants up to 9 months
of age. In the current study, although none of the mothers smoked tobacco, almost 9.4% mothers
used chewing tobacco during pregnancy. However, studies showed diverse findings on harmful
consequences for adverse health outcomes in newborns by prenatal smokeless tobacco. A
systematic review summarized that smokeless tobacco were significantly associated with low
birth weight in 5 out of 7 studies, preterm birth in 3 out of 6 studies, stillbirth in all 4 studies and
assessing small for gestation age in 1 out of 2 studies (Inamdar et al., 2015).
It is also worth mentioning that we observed differential effect on fever in first three
months by different types of fuel. This may be caused by the differences in PM2.5 concentrations
between cow dung, wood, and crop residues. For instance, the use of dung for cooking and
heating had higher EFPM2.5 (EF: emission factors) emission than other biomass fuels and
consistently produced more PM2.5 and OC than burning hardwood and twigs (Jayarathne et al.,
19

2018). Also, a crude association of pneumonia with coal, wood, and cow dung in a case-control
study suggested infants and young children had higher odds of the pneumonia prevalence among
cow dung users rather than those using wood and coal (Mahalanabis et al., 2002).
Strengths of the present study include a longitudinal pregnancy cohort design, outcomes
of interest were assessed at multiple time points in infancy to allow exploration of age of onset of
very early life wheeze, well characterization of household cooking fuel types to allow
investigation the impact of each fuel type on health outcomes and a relatively large sample size.
The results of our findings were consistent with previous studies. To improve the accuracy of the
study results, further work is needed to assess the PM2.5 concentration levels for each fuel type
separately.
There are several limitations of our study that needs acknowledgement. While study
subjects used one predominant fuel type for cooking, there were likely to be have been use of
other fuel types in some seasons that may have resulted in misclassification of exposures. This
misclassification is likely to be non-differential in nature and unlikely to result in observing
spurious associations. Even though we had trained field workers to conduct in person survey
with mothers, reliability of mother’s ability to remember age of onset of respiratory outcomes
may not be accurate. Since such recalls are not likely to be related with outcomes, maternal recall
is likely to be nondifferential in nature and not likely to introduce any bias. Moreover, infants are
likely to spend more time indoor or close to the mother who is involved in the cooking activity,
but we did not assess the postnatal information regarding the exposure to fuel type. We only had
50 households using LPG or electricity, which may have led to observing risk estimates with
broader confidence intervals.
20

Conclusion
Our observations provided evidence that exposure to biomass fuel, especially cow dung
and crop residues, puts infants at risk for developing wheeze earlier and having fever in the first
three months of life. Interventions to reduce exposure to biomass fuel combustion during
pregnancy will reduce burden of illness in infants and promote children’s health in developing
nation like Bangladesh.

21

References
Admasie, A., Kumie, A., & Worku, A. (2018). Children under Five from Houses of Unclean
Fuel Sources and Poorly Ventilated Houses Have Higher Odds of Suffering from Acute
Respiratory Infection in Wolaita-Sodo, Southern Ethiopia: A Case-Control Study.
Journal of Environmental and Public Health, 2018, 1–9.
https://doi.org/10.1155/2018/9320603
Balmes, J. R. (2019). Household air pollution from domestic combustion of solid fuels and
health. The Journal of Allergy and Clinical Immunology, 143(6), 1979–1987.
https://doi.org/10.1016/j.jaci.2019.04.016
Bartington, S. E., Bakolis, I., Devakumar, D., Kurmi, O. P., Gulliver, J., Chaube, G., Manandhar,
D. S., Saville, N. M., Costello, A., Osrin, D., Hansell, A. L., & Ayres, J. G. (2017).
Patterns of domestic exposure to carbon monoxide and particulate matter in households
using biomass fuel in Janakpur, Nepal. Environmental Pollution, 220, 38–45.
https://doi.org/10.1016/j.envpol.2016.08.074
Bates, M. N., Pokhrel, A. K., Chandyo, R. K., Valentiner-Branth, P., Mathisen, M., Basnet, S.,
Strand, T. A., Burnett, R. T., & Smith, K. R. (2018). Kitchen PM2.5 concentrations and
child acute lower respiratory infection in Bhaktapur, Nepal: The importance of fuel type.
Environmental Research, 161, 546–553. https://doi.org/10.1016/j.envres.2017.11.056
Bates Michael N., Chandyo Ram K., Valentiner-Branth Palle, Pokhrel Amod K., Mathisen
Maria, Basnet Sudha, Shrestha Prakash S., Strand Tor A., & Smith Kirk R. (2013). Acute
Lower Respiratory Infection in Childhood and Household Fuel Use in Bhaktapur, Nepal.
Environmental Health Perspectives, 121(5), 637–642.
https://doi.org/10.1289/ehp.1205491
22

Cardoso, M.-R. A., Nascimento-Carvalho, C. M., Ferrero, F., Alves, F. M., & Cousens, S. N.
(2011). Adding fever to WHO criteria for diagnosing pneumonia enhances the ability to
identify pneumonia cases among wheezing children. Archives of Disease in Childhood,
96(1), 58–61. https://doi.org/10.1136/adc.2010.189894
Creation of a Wealth Index, June 2017 | World Food Programme. (2017, June 30).
https://www.wfp.org/publications/creation-wealth-index-june-2017
Dhimal, M., Baral, K., Shrestha, N., Dhakal, P., & Maskey, M. K. (2010). Environmental Burden
of Acute Respiratory Infection and Pneumonia due to Indoor Smoke. Journal of Nepal
Health Research Council. https://doi.org/10.33314/jnhrc.v0i0.213
Djelantik, I. G. G., Gessner, B. D., Sutanto, A., Steinhoff, M., Linehan, M., Moulton, L. H., &
Arjoso, S. (2003). Case fatality proportions and predictive factors for mortality among
children hospitalized with severe pneumonia in a rural developing country setting.
Journal of Tropical Pediatrics, 49(6), 327–332. https://doi.org/10.1093/tropej/49.6.327
Falagas, M. E., Mourtzoukou, E. G., & Vardakas, K. Z. (2007). Sex differences in the incidence
and severity of respiratory tract infections. Respiratory Medicine, 101(9), 1845–1863.
https://doi.org/10.1016/j.rmed.2007.04.011
Ferdous, F., Ahmed, S., Das, S. K., Chisti, M. J., Nasrin, D., Kotloff, K. L., Levine, M. M.,
Nataro, J. P., Ma, E., Muhsen, K., Wagatsuma, Y., Ahmed, T., & Faruque, A. S. G.
(2018). Pneumonia mortality and healthcare utilization in young children in rural
Bangladesh: A prospective verbal autopsy study. Tropical Medicine and Health, 46(1),
1–10. https://doi.org/10.1186/s41182-018-0099-4
Fish, E. N. (2008). The X-files in immunity: Sex-based differences predispose immune
responses. Nature Reviews Immunology, 8(9), 737–744. https://doi.org/10.1038/nri2394
23

Gurley, E. S., Salje, H., Homaira, N., Ram, P. K., Haque, R., Petri, W. A., Bresee, J., Moss, W.
J., Luby, S. P., Breysse, P., & Azziz-Baumgartner, E. (2014). Indoor Exposure to
Particulate Matter and Age at First Acute Lower Respiratory Infection in a Low-Income
Urban Community in Bangladesh. American Journal of Epidemiology, 179(8), 967–973.
https://doi.org/10.1093/aje/kwu002
Haider, M. R., Rahman, M. M., Islam, F., & Khan, M. M. (2016). Association of Low
Birthweight and Indoor Air Pollution: Biomass Fuel Use in Bangladesh. Journal of
Health and Pollution, 6(11), 18–25. https://doi.org/10.5696/2156-9614-6-11.18
Inamdar, A. S., Croucher, R. E., Chokhandre, M. K., Mashyakhy, M. H., & Marinho, V. C. C.
(2015). Maternal Smokeless Tobacco Use in Pregnancy and Adverse Health Outcomes in
Newborns: A Systematic Review. Nicotine & Tobacco Research, 17(9), 1058–1066.
https://doi.org/10.1093/ntr/ntu255
Jashimuddin, M., Masum, K. M., & Salam, M. A. (2006). Preference and consumption pattern of
biomass fuel in some disregarded villages of Bangladesh. Biomass and Bioenergy, 30(5),
446–451. https://doi.org/10.1016/j.biombioe.2005.11.023
Jayarathne, T., Stockwell, C. E., Bhave, P. V., Praveen, P. S., Rathnayake, C. M., Islam, M. R.,
Panday, A. K., Adhikari, S., Maharjan, R., Goetz, J. D., DeCarlo, P. F., Saikawa, E.,
Yokelson, R. J., & Stone, E. A. (2018). Nepal Ambient Monitoring and Source Testing
Experiment (NAMaSTE): Emissions of particulate matter from wood- and dung-fueled
cooking fires, garbage and crop residue burning, brick kilns, and other sources.
Atmospheric Chemistry and Physics, 18(3), 2259–2286. https://doi.org/10.5194/acp-18-
2259-2018
24

Johannsen, T. H., Main, K. M., Ljubicic, M. L., Jensen, T. K., Andersen, H. R., Andersen, M. S.,
Petersen, J. H., Andersson, A.-M., & Juul, A. (2018). Sex Differences in Reproductive
Hormones During Mini-Puberty in Infants With Normal and Disordered Sex
Development. The Journal of Clinical Endocrinology & Metabolism, 103(8), 3028–3037.
https://doi.org/10.1210/jc.2018-00482
Kabera, T., Bartington, S., Uwanyirigira, C., Abimana, P., & Pope, F. (2020). Indoor PM2.5
characteristics and CO concentration in households using biomass fuel in Kigali,
Rwanda. International Journal of Environmental Studies, 77(6), 998–1011.
https://doi.org/10.1080/00207233.2020.1732067
Lee, A. G., Kaali, S., Quinn, A., Delimini, R., Burkart, K., Opoku-Mensah, J., Wylie, B. J.,
Yawson, A. K., Kinney, P. L., Ae-Ngibise, K. A., Chillrud, S., Jack, D., & Asante, K. P.
(2018). Prenatal Household Air Pollution Is Associated with Impaired Infant Lung
Function with Sex-Specific Effects. Evidence from GRAPHS, a Cluster Randomized
Cookstove Intervention Trial. American Journal of Respiratory and Critical Care
Medicine, 199(6), 738–746. https://doi.org/10.1164/rccm.201804-0694OC
Li, Z., Tang, Y., Song, X., Lazar, L., Li, Z., & Zhao, J. (2019). Impact of ambient PM2.5 on
adverse birth outcome and potential molecular mechanism. Ecotoxicology and
Environmental Safety, 169, 248–254. https://doi.org/10.1016/j.ecoenv.2018.10.109
Mahalanabis, D., Gupta, S., Paul, D., Gupta, A., Lahiri, M., & Khaled, M. A. (2002). Risk
factors for pneumonia in infants and young children and the role of solid fuel for
cooking: A case-control study. Epidemiology and Infection, 129(1), 65–71.
https://doi.org/10.1017/S0950268802006817
25

Margolis, P. A., Greenberg, R. A., Keyes, L. L., LaVange, L. M., Chapman, R. S., Denny, F. W.,
Bauman, K. E., & Boat, B. W. (1992). Lower respiratory illness in infants and low
socioeconomic status. American Journal of Public Health, 82(8), 1119–1126.
https://doi.org/10.2105/AJPH.82.8.1119
Martinez, F. D., Wright, A. L., Holberg, C. J., Morgan, W. J., & Taussig, L. M. (1992). Maternal
Age as a Risk Factor for Wheezing Lower Respiratory Illnesses in the First Year of Life.
American Journal of Epidemiology, 136(10), 1258–1268.
https://doi.org/10.1093/oxfordjournals.aje.a116434
Masud, M. H., Ananno, A. A., Arefin, A. M. E., Ahamed, R., Das, P., & Joardder, M. U. H.
(2019). Perspective of biomass energy conversion in Bangladesh. Clean Technologies
and Environmental Policy, 21(4), 719–731. https://doi.org/10.1007/s10098-019-01668-2
Muenchhoff, M., & Goulder, P. J. R. (2014). Sex Differences in Pediatric Infectious Diseases.
The Journal of Infectious Diseases, 209(suppl_3), S120–S126.
https://doi.org/10.1093/infdis/jiu232
Mulenga, D., & Siziya, S. (2019). Indoor Air Pollution Related Respiratory Ill Health, a Sequel
of Biomass Use. SciMedicine Journal, 1(1), 30–37. https://doi.org/10.28991/SciMedJ-
2019-0101-5
Pokhrel, A. K., Bates, M. N., Acharya, J., Valentiner-Branth, P., Chandyo, R. K., Shrestha, P. S.,
Raut, A. K., & Smith, K. R. (2015). PM2.5 in household kitchens of Bhaktapur, Nepal,
using four different cooking fuels. Atmospheric Environment, 113, 159–168.
https://doi.org/10.1016/j.atmosenv.2015.04.060
R Core Team (2020). R: A language and environment for statistical computing. R Foundation for
Statistical Computing, Vienna, Austria. URL https://www.R-project.org/.
26

Sanbata, H., Asfaw, A., & Kumie, A. (2014). Association of biomass fuel use with acute
respiratory infections among under- five children in a slum urban of Addis Ababa,
Ethiopia. BMC Public Health, 14(1), 1122. https://doi.org/10.1186/1471-2458-14-1122
Smith, K. R., Mehta, S., & Maeusezahl-Feuz, M. (2004). Indoor air pollution from household use
of solid fuels. Comparative quantification of health risks: global and regional burden of
disease attributable to selected major risk factors, 2, 1435-1493.
Tielsch, J. M., Katz, J., Thulasiraj, R. D., Coles, C. L., Sheeladevi, S., Yanik, E. L., &
Rahmathullah, L. (2009). Exposure to indoor biomass fuel and tobacco smoke and risk of
adverse reproductive outcomes, mortality, respiratory morbidity and growth among
newborn infants in south India. International Journal of Epidemiology, 38(5), 1351–
1363. https://doi.org/10.1093/ije/dyp286
WHO | WHO Guidelines for indoor air quality: Household fuel combustion. (2014). WHO;
World Health Organization. http://www.who.int/airpollution/guidelines/household-fuel-
combustion/en/
World Health Organization. Occupational and Environmental Health Team. (2006). WHO Air
quality guidelines for particulate matter, ozone, nitrogen dioxide and sulfur dioxide :
global update 2005 : summary of risk assessment. World Health
Organization. https://apps.who.int/iris/handle/10665/69477
World Health Organization: WHO. (2018, May 8). Household air pollution and health.
https://www.who.int/en/news-room/fact-sheets/detail/household-air-pollution-and-health
World Health Organization. Programme of Acute Respiratory Infections. (1990). Acute
respiratory infections in children : case management in small hospitals in developing
27

countries, a manual for doctors and other senior health workers. World Health
Organization. https://apps.who.int/iris/handle/10665/61873
Williams, A., Jones, J. M., Ma, L., & Pourkashanian, M. (2012). Pollutants from the combustion
of solid biomass fuels. Progress in Energy and Combustion Science, 38(2), 113–137.
https://doi.org/10.1016/j.pecs.2011.10.001

Abstract (if available)

Abstract Background: Exposure to biomass fuel use is associated with a higher risk of respiratory outcomes among children under 5 years of age, but little evidence exists about the effects of different biomass fuel types on respiratory health outcomes or the age of onset among infants. This study aims to evaluate whether compared to liquid petroleum gas (LPG)/electricity, the use of wood, cow dung, and crop residue for cooking is associated with 1) respiratory health outcomes in infants and 2) age of onset of respiratory ailments in a Bangladeshi pregnancy cohort. ❧ Methods: From 2016 to 2017, we recruited 903 pregnant women within confirmed 18 weeks of gestation and followed them at study entry, birth, and every 3 months during the first year after delivery (2017-2019). We collected data on household characteristics, socio-demographics, and respiratory health outcomes of infants. Multivariate analyses were conducted using fuel type as the exposure variable of interest, adjusting for identified confounders. For binary respiratory outcomes we used logistic regression, for categorical outcomes we used multinomial regression, and for continuous respiratory outcomes we used linear regression. ❧ Results: About 55% households used wood (n=442) as primary fuel for cooking, while 27% used crop residues (n=215), 12% used cow dung, and only 6% used LP gas or electricity. Adjusted mean age of wheeze onset in infants was 101 days, and it was significantly (p<0.05) earlier in households using cow dung (75 days), wood (76 days), and crop residues (77 days). The odds of developing fever in the first three months of life were more than 2-fold higher among infants from households using cow dung (OR: 2.49, 95% CI: 1.16−5.44) and crop residues (OR: 2.42, 95% CI: 1.19−4.95) compared to infants from households using LP gas or electricity. In addition, in multivariate analysis, we found that female infants had significant lower risk of fever and cough in the first 3 months of life (OR: 0.64, 95% CI: 0.47−0.85 for fever and OR: 0.66, 95% CI: 0.49−0.88 for cough) compared with male infants. ❧ Conclusion: Prenatal exposure to biomass fuel, especially cow dung and crop residues, puts infants at higher risk for developing wheeze earlier and having fever in the first three months of life. Interventions to reduce exposure to biomass fuel combustion during pregnancy will reduce burden of illness in infants and promote children’s health in developing nation like Bangladesh.

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Asset Metadata

Creator Wang, Lin (author)

Core Title Effect of biomass fuel exposure on infant respiratory health outcomes in Bangladesh

School Keck School of Medicine

Degree Master of Science

Degree Program Applied Biostatistics and Epidemiology

Publication Date 04/08/2021

Defense Date 04/08/2021

Publisher University of Southern California (original), University of Southern California. Libraries (digital)

Tag age of onset,Bangladesh,biomass fuel,cough,crop residue,Fever,infant respiratory outcomes,OAI-PMH Harvest,wheeze

Language English

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Advisor Islam, Talat (committee chair), Franklin, Meredith (committee member), Salam, Towhid (committee member)

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