Donee Alexander

Randomized Controlled Ethanol Cookstove Intervention and Blood Pressure in Pregnant Nigerian Women

Rationale: Hypertension during pregnancy is a leading cause of maternal mortality. Exposure to household air pollution elevates blood pressure (BP). Objectives: To investigate the ability of a clean cookstove intervention to lower BP during pregnancy. Methods: We conducted a randomized controlled trial in Nigeria. Pregnant women cooking with kerosene or firewood were randomly assigned to an ethanol arm (n = 162) or a control arm (n = 162). BP measurements were taken during six antenatal visits. In the primary analysis, we compared ethanol users with control subjects. In subgroup analyses, we compared baseline kerosene users assigned to the intervention with kerosene control subjects and compared baseline firewood users assigned to ethanol with firewood control subjects. Measurements and Main Results: The change in diastolic blood pressure (DBP) over time was significantly different between ethanol users and control subjects (P = 0.040); systolic blood pressure (SBP) did not differ (P = 0.86). In subgroup analyses, there was no significant intervention effect for SBP; a significant difference for DBP (P = 0.031) existed among preintervention kerosene users. At the last visit, mean DBP was 2.8 mm Hg higher in control subjects than in ethanol users (3.6 mm Hg greater in control subjects than in ethanol users among preintervention kerosene users), and 6.4% of control subjects were hypertensive (SBP ≥140 and/or DBP ≥90 mm Hg) versus 1.9% of ethanol users (P = 0.051). Among preintervention kerosene users, 8.8% of control subjects were hypertensive compared with 1.8% of ethanol users (P = 0.029). Conclusions: To our knowledge, this is the first cookstove randomized controlled trial examining prenatal BP. Ethanol cookstoves have potential to reduce DBP and hypertension during pregnancy. Accordingly, clean cooking fuels may reduce adverse health impacts associated with household air pollution. Clinical trial registered with www.clinicaltrials.gov (NCT02394574).

Ventilated cookstoves associated with improvements in respiratory health-related quality of life in rural Bolivia

BACKGROUND Household air pollution (HAP) from combustion of biomass fuels worldwide is linked to asthma, respiratory infections and chronic pulmonary diseases. Implementation of ventilated cookstoves significantly reduces exposure to HAP. However, improvements in concurrent respiratory health-related quality of life (HRQoL) have not been previously evaluated with a standardized questionnaire. METHODS The association between woodsmoke exposure and respiratory HRQoL outcomes was evaluated using an intervention study in a rural community in Bolivia. Indoor carbon monoxide (CO) levels from traditional stoves and from cookstoves with chimneys were analyzed alongside interview results of women heads-of-households using the St. Georges Respiratory Questionnaire (SGRQ) in 2009 and 1-year post-intervention. RESULTS Pronounced improvements in respiratory HRQoL and significant reductions of household CO levels followed installation of ventilated cookstoves. Stove implementation yielded lower indoor CO values and correlated positively with improved SGRQ scores. CONCLUSIONS This is the first use of a standardized respiratory HRQoL assessment to determine the impact of ventilated cookstove implementation on reducing HAP. This preliminary study utilizes the SGRQ as a valuable tool enabling analysis of these health effects in relation to other respiratory disease states.

Effect of a clean stove intervention on inflammatory biomarkers in pregnant women in Ibadan, Nigeria: A randomized controlled study

BACKGROUND Exposure to household air pollution (HAP) has been linked to systemic inflammation. We determined the impact of transition from traditional firewood/kerosene stove to bioethanol-burning stove on inflammatory biomarkers in pregnant Nigerian women. METHODS Women (n=324), cooking with kerosene/firewood, were recruited during their first trimester of pregnancy from June 2013-October 2015 and were randomly allocated to either control (n=162) or intervention (n=162) group using web-based randomization. Controls continued to use their own firewood/kerosene stove, while intervention participants received bioethanol CleanCook stoves. Serum concentrations of retinol-binding protein (RBP), malondialdehyde (MDA), tumor necrosis factor alpha (TNF)-α, interleukin (IL)-6, and IL-8 were measured by ELISA. RESULTS After excluding 53 women (loss of follow-up, untimely biomarker assessments, incorrect dates of enrollment), data from 271 women were included in analysis. Mean (SD) change in RBP, MDA, TNF-α, IL-6, and IL-8 between baseline and third trimester was -2.16 (4.47), -19.6 (46.4), 3.72 (37.2), 0.51 (14.4), and 13.2 (197), respectively, in intervention and -2.25 (4.30), -24.6 (43.6), 7.17 (32.6), -1.79, (11.4), and 31.3 (296) in control groups. None of these changes differed significantly between the two treatment arms. However, changes from baseline in TNF-α levels were significantly different between intervention and control groups in subset of women (n=99) using firewood before trial (-7.03 [32.9] vs. +12.4 [33.6]; 95% CI for group difference: -35.4 to -3.4, p=0.018). CONCLUSIONS Decrease in TNF-α concentration from baseline to third trimesters in intervention group women could indicate reduced cardiovascular stress and prothrombotic effects from decreased HAP. Our findings suggest that ethanol-burning stoves may mitigate cardiovascular health risks.

Pregnancy Outcomes and Ethanol Cook stove intervention: A randomized-controlled trial in Ibadan, Nigeria.

BACKGROUND Household air pollution (HAP) exposure has been linked to adverse pregnancy outcomes. OBJECTIVES A randomized controlled trial was undertaken in Ibadan, Nigeria to determine the impact of cooking with ethanol on pregnancy outcomes. METHODS Three-hundred-twenty-four pregnant women were randomized to either the control (continued cooking using kerosene/firewood stove, n=162) or intervention group (received ethanol stove, n=162). Primary outcome variables were birthweight, preterm delivery, intrauterine growth restriction (IUGR), and occurrence of miscarriage/stillbirth. RESULTS Mean birthweights for ethanol and controls were 3076 and 2988g, respectively; the difference, 88g, (95% confidence interval: -18g to 194g), was not statistically significant (p=0.10). After adjusting for covariates, the difference reached significance (p=0.020). Rates of preterm delivery were 6.7% (ethanol) and 11.0% (control), (p=0.22). Number of miscarriages was 1(ethanol) vs. 4 (control) and stillbirths was 3 (ethanol) vs. 7 (control) (both non-significant). Average gestational age at delivery was significantly (p=0.015) higher in ethanol-users (39.2weeks) compared to controls (38.2weeks). Perinatal mortality (stillbirths and neonatal deaths) was twice as high in controls compared to ethanol-users (7.9% vs. 3.9%; p=0.045, after adjustment for covariates). We did not detect significant differences in exposure levels between the two treatment arms, perhaps due to large seasonal effects and high ambient air pollution levels. CONCLUSIONS Transition from traditional biomass/kerosene fuel to ethanol reduced adverse pregnancy outcomes. However, the difference in birthweight was statistically significant only after covariate adjustment and the other significant differences were in tertiary endpoints. Our results are suggestive of a beneficial effect of ethanol use. Larger trials are required to validate these findings.

Household air pollution and chronic hypoxia in the placenta of pregnant Nigerian women: A randomized controlled ethanol Cookstove intervention.

BACKGROUND Household air pollution (HAP) is associated with adverse pregnancy outcomes. OBJECTIVES Investigate impact of in-utero HAP exposure on placental development and chronic hypoxia. METHODS Markers of chronic placental hypoxia [Hofbauer cells (HBC), syncytial knots (SK), chorionic vascular density (cVD) and hypoxia-inducible factor (HIF)] were stained by hematoxylin-eosin and/or immunohistochemically in placenta samples collected from firewood-/kerosene-users (A,n=16), and ethanol-users (B,n=20) that participated in a randomized controlled intervention trial in Ibadan, Nigeria. A third group of non-smoking and presumed natural gas-using Chicago women (C,n=12) were included in this exploratory pilot to assess for possible differences in placenta histology between similar racial groups. All patients had uncomplicated pregnancies and delivered at term. RESULTS HBC, SK and cVD were significantly increased among firewood-/kerosene-users compared to ethanol-users and natural gas-using Chicago women (HBC medians 5.5, 3.5, and 2.0, respectively; SK means 55.6, 41.8 and 30.1; cVD means 8.8, 6.2, and 5.2; all p<0.01). HIF expression was significantly higher in Group A compared to B and C (all p<0.001). CONCLUSIONS In-utero exposure to HAP is associated with pathologic changes and HIF expression consistent with chronic hypoxia in placenta of firewood/kerosene-users compared to ethanol-users with less HAP exposure and Chicago women with no presumed HAP exposure. Presence of chronic hypoxic signature in placenta of women exposed to HAP has implications for adverse pregnancy complications and future growth and development of the young children. Future larger studies need to focus on HAP exposure and placental disorders like preeclampsia and long-term health impact of in-utero exposure to HAP.

Household air pollution and angiogenic factors in pregnant Nigerian women: A randomized controlled ethanol cookstove intervention

BACKGROUND Maternal exposure to ambient air pollution affects placental growth markers. OBJECTIVES Investigate impact of household air pollution (HAP) on placental growth markers. METHODS Two groups of pregnant women were identified: firewood/kerosene stove-users (A, n=33) and bioethanol stove-users (B, n=44) that participated in a randomized control trial in Ibadan, Nigeria. A third group of non-smoking and presumed liquefied petroleum gas-using Chicago women (C, n=19) were included in this exploratory pilot to assess for possible differences between similar racial groups. Levels of placental growth factor (PlGF) and soluble fms-like tyrosine kinase 1 (sFlt-1) were measured in maternal and cord plasma using ELISA. RESULTS Maternal and cord blood sFlt-1 and PlGF did not differ significantly between women of groups A and B. Nevertheless, both groups differed significantly from the Chicago group in that group A women had lower maternal sFlt-1 (1372.50 vs. 3194.19) but higher PlGF (1607.87 vs. 442.80), and higher cord blood sFlt-1 (2925.02 vs. 107.53) and PlGF (223.68 vs. 6.92), all p≤0.001. Group B showed similar trends (all p≤0.002). Maternal PlGF levels were positively correlated to minutes of HAP exposure when PM2.5 concentration was above 100μg/m3 in Nigerian women. CONCLUSIONS Maternal levels of PlGF and cord blood levels of sFlt-1 and PlGF in Nigerian women with varying HAP exposures were significantly higher than Chicago-based women who had no presumed HAP exposure. It suggests that in-utero exposure to HAP influenced levels of angiogenic factors involved in normal placentation and growth and could represent compensation for pollutants exposure to preserve fetal viability.