Is Indoor Air Pollution From Different Fuel Types Associated With the Anemia Status of Pregnant Women in Ethiopia?

Association between exposure to smoke from cooking fuels and anaemia among women of reproductive age in Ghana

In low- and middle-income countries, indoor air pollution (IAP) is a serious public health concern, especially for women and children who cook with solid fuels. IAP exposure has been linked to a number of medical conditions, including pneumonia, ischemic heart disease, stroke, chronic obstructive pulmonary disease (COPD), lung cancer, and anaemia. Around 500 million women of reproductive age (WRA) suffer from anaemia globally, with an estimated 190 million cases in sub-Saharan Africa (SSA). This study, which is based on prior research, investigates the relationship between IAP exposure and anaemia among WRA in Ghana. A diverse sample of 2,406 WRA living in Ghana were interviewed, of which 58.06% were anaemic and used high-pollutant fuels for cooking. Age, place of residence, region, education level, religion, ethnicity, wealth index, type of drinking water, type of toilet facility, and type of cooking fuels were all found to be significantly linked with anaemic state by bivariate analysis. Type of cooking fuels utilized, age, region of residence, and the type of residence were shown to be significant predictors of anaemia status using sequential binary logit regression models. The results emphasise the critical need for efforts to promote the usage of clean cooking fuel in an attempt to lower anaemia prevalence in Ghana. To reduce dependency on solid fuels for cooking, initiatives should promote the use of cleaner cooking fuels and enhance the socioeconomic status of households. These interventions could have significant public health effects by reducing the burden of anaemia and improving maternal and child health outcomes due to the prevalence of anaemia among WRA. Overall, this study sheds light on the relationship between IAP exposure and anaemia in Ghana and highlights the demand for focused public health initiatives to address this serious health problem.

Factors Affecting Anemia among Women of Reproductive Age in Mexico: A Mixed-Methods Country Case Study

BACKGROUND

In Mexico, anemia prevalence among women of reproductive age (WRA) decreased from 16.4% in 2006 to 11.6% in 2012, only to increase to 18.3% in 2016. The factors associated with this fluctuation are uncertain.

OBJECTIVE

We conducted a systematic in-depth assessment of the quantitative and qualitative determinants of anemia among WRA in Mexico between 2006 and 2018.

METHODS

Using multivariate stepwise linear regression, we analyzed Mexico's Encuesta Nacional de Salud y Nutrición (ENSANUT) surveys from 2006, 2012, and 2018 to identify determinants of WRA anemia. We also conducted a review of anemia-relevant programs and policies, including financing documents, and conducted in-depth interviews and focus group discussions with key stakeholders in Mexico.

RESULTS

Among non-pregnant women (NPW) 15-49 years, mean hemoglobin (Hb) increased from 13.8 g/dL in 2006 to 14.0 g/dL in 2012, decreasing to 13.2 g/dL in 2018 (p<0.001). Inequities by geographical region and household wealth persisted throughout this period, with household wealth, urban residence and gravidity emerging as significant predictors of Hb among NPW. Qualitative analyses generally supported these findings. The most discussed program was Progresa-Oportunidades-Prospera (POP), where most resources for health were invested and most participants acknowledged that its cancellation in 2019 would lead to worsening in health and nutrition among the poor. Financing analyses showed a drop of funding for nutrition-related programs between 2014 and 2018. Cultural norms around gender roles were still prevalent, along with increasing rates of teenage pregnancy.

CONCLUSIONS

Anemia prevention efforts need to refocus on poverty alleviation, continuity of adequate coverage and financing of nutrition programs, especially with safety nets, and increase in uptake of family planning, especially among adolescent girls.

Association of household air pollution exposure and anemia among pregnant women: Analysis of baseline data from 'Household Air Pollution Intervention Network (HAPIN)' trial

BACKGROUND

Anemia is common in low- and middle-income countries (LMICs), causing significant health issues and social burdens. Exposure to household air pollution from using biomass fuels for cooking and heating has been associated with anemia, but the exposure-response association has not been studied.

OBJECTIVES

We evaluated the associations between personal exposure to air pollution and both hemoglobin levels and anemia prevalence among pregnant women in a multi-country randomized controlled trial.

METHODS

We studied 3,163 pregnant women aged 18-35 years with 9-20 weeks of gestation, recruited as part of the Household Air Pollution Intervention Network (HAPIN) randomized controlled trial in Guatemala, India, Peru, and Rwanda. We assessed 24-hour personal exposures to fine particulate matter (PM2.5), black carbon (BC), and carbon monoxide (CO), and measured hemoglobin levels at baseline (15 ± 3 weeks gestation). Linear and logistic regression models were used to examine the associations of measured pollutants with hemoglobin levels and anemia prevalence, adjusting for confounding.

RESULTS

Single-pollutant models showed associations of CO with higher hemoglobin levels and lower anemia prevalence. Bipollutant models involving CO and PM2.5 also revealed that an interquartile range (IQR) increase in CO concentrations (2.26 ppm) was associated with higher hemoglobin levels [β = 0.04; 95 % confidence interval (CI): 0.01, 0.07], and a lower odds of anemia prevalence [odds ratios (OR) = 0.90; 95 % CI: 0.83, 0.98]. PM2.5 was inversely related to hemoglobin and positively associated with anemia, but results were not statistically significant at the 0.05 alpha level. County-specific results showed that 3 of 4 countries showed a similar association between CO and hemoglobin. We found no association of BC levels with hemoglobin levels or with anemia prevalence.

CONCLUSION

Our findings suggest that exposure to CO is associated with higher hemoglobin and lower anemia prevalence among pregnant women, whereas PM2.5 showed the opposite associations.

Smoke exposure, hemoglobin levels and the prevalence of anemia: a cross-sectional study in urban informal settlement in Southern Ghana

BACKGROUND

In sub-Saharan African cities, more than half of the population lives in informal settlements. These settlements are close to smoky dumpsites, industrial plants, and polluted roads. Furthermore, polluting fuels remain their primary sources of energy for cooking and heating. Despite evidence linking smoke and its components to anaemia, none of these studies were conducted on populations living in urban informal settlements. This study investigated the risks of anemia/mean Haemoglobin (HB) levels in an informal settlement in Accra, Ghana. Exposure to smoke was examined across various sources, encompassing residences, neighborhoods, and workplaces.

METHODS

The study was a facility-based cross-sectional design among residents at Chorkor, an informal settlement in the Greater Accra region of Ghana. A questionnaire was administered at a community hospital during an interview to gather data on sources of smoke exposure in the household, in the neighbourhood, and in the workplace. A phlebotomist collected blood samples from the participants after the interview to assess their anaemia status.

RESULTS

The population (n = 320) had a high prevalence of anemia, with 49.1% of people fitting the WHO's definition of anemia, while the average HB level was 12.6 ± 2.1 g/dL. Anemia was associated with the number of different types of waste burnt simultaneously [(1 or 2: prevalence ratio (PR): 95% confidence interval (CI), 1.14, 0.99-1.28: 3+: 1.16, 1.01-1.63, p-for-trend = 0.0082)], fuel stacking [(mixed stacking: 1.27, 1.07-1.20: dirty stacking:1.65, 1.19-2.25, p-for-trend = 0.0062)], and involvement in fish smoking (1.22, 0.99-1.06). However, the lower limit of the CIs for number of different forms of garbage burned simultaneously and engagement in fish smoking included unity. Reduced mean HB levels were associated with the number of different types of waste burnt simultaneously [(1 or 2: regression coefficient (β): 95% confidence interval (CI), -0.01, -0.97- -0.99: 3+: -0.14, -0.77- -0.05)], current smoker [(yes, almost daily: -1.40, -2.01- -0.79: yes, at least once a month: -1.14, -1.79- -0.48)], Second-Hand-Smoking (SHS) (yes, almost daily: -0.77, -1.30- -0.21), fuel stacking [(mixed stacking-0.93, -1.33-0.21: dirty stacking-1.04, -1.60- -0.48)], any smoke exposure indicator in the neighbourhood (-0.84, -1.43- -0.25), living close to a major road (-0.62, -1.09- -0.49), and fish smoking (-0.41,-0.93- -0.12).

CONCLUSION

Although the cross-sectional design precludes causality, smoke exposure was associated with mean HB levels and anaemia among populations living in informal settlements.

Exposure to air pollution as a risk factor for anaemia: a global scoping review

Anaemia is an important global health issue with various factors responsible for its occurrence. Though nutritional deficiency is one of the main causes of the disease, evidence suggests a potential link between long-term exposure to ambient air pollution and an increased risk of developing anaemia. Our scoping review evaluates studies conducted across the world to examine possible associations between anaemia and ambient air pollution. Six databases were searched, 153 sources were identified, and 21 articles were included in the review. Apart from one article which showed no significant effect, studies reported positive associations between anaemia and air pollution. This was true for both indoor and outdoor air pollution, various types of particulate matter exposure, and across demographic groups. The review highlights the importance of recognizing exposure to air pollution as a potential risk factor for anaemia and emphasizes the imperative for focused interventions and policy measures to mitigate air pollution.

Prenatal Exposure to Air Pollution and Pre-Labor Rupture of Membranes in a Prospective Cohort Study: The Role of Maternal Hemoglobin and Iron Supplementation

BACKGROUND

Exposure to air pollution in prenatal period is associated with prelabor rupture of membranes (PROM). However, the sensitive exposure time windows and the possible biological mechanisms underlying this association remain unclear.

OBJECTIVE

We aimed to identify the sensitive time windows of exposure to air pollution for PROM risk. Further, we examined whether maternal hemoglobin levels mediate the association between exposure to air pollution and PROM, as well as investigated the potential effect of iron supplementation on this association.

METHOD

From 2015 to 2021, 6,824 mother-newborn pairs were enrolled in the study from three hospitals in Hefei, China. We obtained air pollutant data [particulate matter (PM) with aerodynamic diameter ≤2.5μm (PM2.5), PM with aerodynamic diameter ≤10μm (PM10), sulfur dioxide (SO2), and carbon monoxide (CO)] from the Hefei City Ecology and Environment Bureau. Information on maternal hemoglobin levels, gestational anemia, iron supplementation, and PROM was obtained from medical records. Logistic regression models with distributed lags were used to identify the sensitive time window for the effect of prenatal exposure to air pollutant on PROM. Mediation analysis estimated the mediated effect of maternal hemoglobin in the third trimester, linking prenatal air pollution with PROM. Stratified analysis was used to investigate the potential effect of iron supplementation on PROM risk.

RESULTS

We found significant association between prenatal exposure to air pollution and increased PROM risk after adjusting for confounders, and the critical exposure windows of PM2.5, PM10, SO2 and CO were the 21th to 24th weeks of pregnancy. Every 10-μg/m3 increase in PM2.5 and PM10, 5-μg/m3 increase in SO2, and 0.1-mg/m3 increase in CO was associated with low maternal hemoglobin levels [-0.94g/L (95% confidence interval (CI): -1.15, -0.73), -1.31g/L (95% CI: -1.55, -1.07), -2.96g/L (95% CI: -3.32, -2.61), and -1.11g/L (95% CI: -1.31, -0.92), respectively] in the third trimester. The proportion of the association between air pollution and PROM risk mediated by hemoglobin levels was 20.61% [average mediation effect (95% CI): 0.02 (0.01, 0.05); average direct effect (95%): 0.08 (0.02, 0.14)]. The PROM risk associated with exposure to low-medium air pollution could be attenuated by maternal iron supplementation in women with gestational anemia.

CONCLUSIONS

Prenatal exposure to air pollution, especially in the 21st to 24th weeks of pregnancy, is associated with PROM risk, which is partly mediated by maternal hemoglobin levels. Iron supplementation in anemia pregnancies may have protective effects against PROM risk associated with exposure to low-medium air pollution. https://doi.org/10.1289/EHP11134.

Is biomass fuel smoke exposure associated with anemia in non-pregnant reproductive-aged women?

Objectives

Sri Lanka is a developing country where the majority of households still rely on firewood for cooking. Furthermore, the prevalence of anemia among reproductive-aged women is of moderate public health importance, according the classification of World Health Organization. Despite the researchers’ ongoing efforts to investigate a link between solid fuel smoke exposure and anemia, the veracity of their findings remains uncertain. As a result, the purpose of this study was to examine the relationship between biomass fuel smoke exposure and anemia in non-pregnant reproductive-aged women in Sri Lanka.

Methods

A descriptive cross-sectional study was conducted among 382 non-pregnant reproductive-aged (15 to 49 years) women in Central Province, Sri Lanka. Data was collected using a standardized interviewer-administered questionnaire, and exposure was assessed using a breath carbon monoxide monitor. Drabkin’s cynomethhemoglobin technique was used to determine blood hemoglobin concentration.

Results

The overall prevalence of anemia was 36.1%. The logistic regression model revealed no effect of cooking fuel type on anemic or non-anemic status after adjusting for potential confounding factors (p > 0.05). The multivariate regression analysis also discovered that cooking fuel type had no effect on women’s blood hemoglobin concentration.

Conclusions

The study results suggest no impact of solid fuel smoke exposure on anemia among non-pregnant, reproductive-aged women. Larger scale prospective cohort studies are recommended. The reasons behind the high prevalence of anemia among reproductive-aged women should be further investigated, and corrective measures should be implemented urgently.

The link between indoor air pollution from cooking fuels and anemia status among non-pregnant women of reproductive age in Ethiopia

Objective:

The effect of indoor air pollution from different fuel types on the anemia status among non-pregnant women is rarely studied. This study aimed to assess the link between indoor air pollution from different fuel types and anemia among non-pregnant women of reproductive ages in Ethiopia.

Method:

The secondary data from the 2016 Ethiopian Demographic and Health Survey data have been employed for this study. The anemia status of women in reproductive age was the outcome variable with multiple outcomes as (moderate to severe, mild, and no anemia) and households using biomass fuel and clean fuel were selected for this study. Multinomial logistic regression was employed to estimate the association of biomass fuel use with the anemia status controlling for the predictor variables. Relative risk ratio was calculated at 95% confidence interval. An independent-sample t-test was used to assess the mean difference in blood hemoglobin level (g/dL) between the two fuel users. A p value < 0.05 was considered significant.

Result:

From the total of 10,961 participants included in this study, the proportion of anemia in women of non-reproductive age was 41.8% and 19.4% among biomass fuel and clean fuel users, respectively, with a mean blood hemoglobin level of 12.71 (±1.81) g/dL. In the final model, women using biomass fuel for cooking were 47% more likely to have mild anemia than households who use cleaner fuels, whereas the association was insignificant for moderate to severe anemia. Biomass fuel users were also found to have 5.8 g/dL lower blood hemoglobin level than the clean fuel user (p < 0.001).

Conclusion:

The use of biomass fuel was associated with reduced blood hemoglobin levels and significantly associated with mild anemia levels in women of reproductive age in Ethiopia. National efforts should be in place to reduce indoor air pollution from biomass fuels.