Associations between biomass fuel use and child health: a community-based study in Bhaktapur, Nepal

Background

Biomass fuel use for cooking is widespread in low- and middle-income countries. Previous studies have mainly focused on adverse health outcomes in adults or specific diseases. In a cohort among young children living in Bhaktapur, Nepal, we aimed to describe the association between the use of biomass cooking fuels in families with child health using measures of linear growth, cognition and chronic illness.

Methods

Caregivers of 600 marginally stunted children aged 6-11 months were interviewed about their primary source of cooking fuel at enrolment into a randomized controlled trial. Children's body length (n = 572) was measured at age 18-23 months. At the same time, blood samples (n = 497) were taken, and we measured leukocyte telomere length (LTL) as a marker of chronic disease risk. We chose LTL expressed as z-scores as a measure of chronic disease. Cognitive abilities were measured by the Wechsler Preschool and Primary Scale of Intelligence, 4th edition (WPPSI-IV) and NEPSY-II subtests when the children were 4 years old (n = 531). Associations were estimated in multiple regression models.

Results

About 18% of all families used biomass as primary cooking fuel. Children from families using biomass fuel were on average slightly shorter (mean difference 0.14 Z-scores, 95% CI: 0.28, 0.00), had lower IQ scores (mean difference 2.2 (95% CI: 0.5, 3.9), and shorter LTL (mean difference: 0.09 (95% CI: 0.05 to 0.13) compared to those not using biomass fuel. The observed associations were unaltered after adjusting for relevant confounders.

Conclusions

In children from households in poor, urban neighborhoods in Nepal, biomass fuel use for cooking was associated with health indicators for child growth and cognition as well as longevity and chronic illnesses reflected in shortening of telomeres. As this was an observational study, residual confounding cannot be excluded. Our findings support the ongoing effort to reduce exposure to biomass fuel in low-resource settings.

Key messages

The prevalence of anemia and iron deficiency is more common in breastfed infants than their mothers in Bhaktapur, Nepal

Background/Objectives:

Iron deficiency anemia is a widespread public health problem, particularly in low- and middle-income countries. Maternal iron status around and during pregnancy may influence infant iron status. We examined multiple biomarkers to determine the prevalence of iron deficiency and anemia among breastfed infants and explored its relationship with maternal and infant characteristics in Bhaktapur, Nepal.

Subjects/Methods:

In a cross-sectional survey, we randomly selected 500 mother–infant pairs from Bhaktapur municipality. Blood was analyzed for hemoglobin, ferritin, total iron-binding capacity, transferrin receptors and C-reactive protein.

Results:

The altitude-adjusted prevalence of anemia was 49% among infants 2–6-month-old (hemaglobin (Hb) <10.8 g/dl) and 72% among infants 7–12-month-old (Hb <11.3 g/dl). Iron deficiency anemia, defined as anemia and serum ferritin <20 or <12 μg/l, affected 9 and 26% of infants of these same age groups. Twenty percent of mothers had anemia (Hb <12.3 g/dl), but only one-fifth was explained by depletion of iron stores. Significant predictors of infant iron status and anemia were infant age, sex and duration of exclusive breastfeeding and maternal ferritin concentrations.

Conclusions:

Our findings suggest that iron supplementation in pregnancy is likely to have resulted in a low prevalence of postpartum anemia. The higher prevalence of anemia and iron deficiency among breastfed infants compared with their mothers suggests calls for intervention targeting newborns and infants.

Prevalence of iron deficiency and anemia among healthy women of reproductive age in Bhaktapur, Nepal

OBJECTIVE

To determine the prevalence of anemia and iron status as assessed by biochemical markers and to explore the associations between markers of iron status and iron intake. STUDY AREA AND POPULATION: Five hundred healthy women of reproductive age from the Bhaktapur district of Nepal were included in the study.

METHODS

A cluster sampling procedure was applied for this cross-sectional study. Women without any ongoing infection aged 13-35 years were selected randomly from the population. We measured the plasma concentration of hemoglobin (Hb), ferritin and transferrin receptors. Dietary information was obtained by a food frequency questionnaire and two 24-h dietary recalls.

RESULTS

The prevalence of anemia (Hb concentration <12 g/dl) was 12% (n=58). The prevalence of depleted iron stores (plasma ferritin <15 microg/l) was 20% (n=98) whereas the prevalence of iron deficiency anemia (anemia, depleted iron stores with elevated transferrin receptor i.e. >1.54 mg/l) was 6% (n=30). Seven percent (n=35) of women were having iron-deficient erythropoiesis (depleted iron stores and elevated transferrin receptor but normal Hb). Out of the 58 anemic women, 41 (71%) and 31 (53%) were also having elevated plasma transferrin receptor and depleted iron stores, respectively. Fifty-four percent of the women ate less than the recommended average intake of iron. The main foods contributing to dietary iron were rice, wheat flour and green and dry vegetables.

CONCLUSIONS

The prevalence of anemia in our study was substantially lower than the national figure for non-pregnant women. Only about half of the women with anemia were also having depleted iron stores, suggesting that other causes of anemia may be prevalent in this population.

SPONSORSHIP

Norwegian Universities Committee for Development, Research and Education (NUFU).