Chimney Stove Intervention to Reduce Long-term Wood Smoke Exposure Lowers Blood Pressure among Guatemalan Women

Abstract

Background and ObjectiveRESPIRE, a randomized trial of an improved cookstove, was conducted in Guatemala to assess health effects of long-term reductions in wood smoke exposure. Given the evidence that ambient particles increase blood pressure, we hypothesized that the intervention would lower blood pressure.MethodsTwo study designs were used: a) between-group comparisons based on randomized stove assignment, and b) before-and-after comparisons within subjects before and after they received improved stoves. From 2003 to 2005, we measured personal fine particle (particulate matter with aerodynamic diameter < 2.5 μm; PM2.5) exposures and systolic (SBP) and diastolic blood pressure (DBP) among women > 38 years of age from the chimney woodstove intervention group (49 subjects) and traditional open wood fire control group (71 subjects). Measures were repeated up to three occasions.ResultsDaily average PM2.5 exposures were 264 and 102 μg/m3 in the control and intervention groups, respectively. After adjusting for age, body mass index, an asset index, smoking, secondhand tobacco smoke, apparent temperature, season, day of week, time of day, and a random subject intercept, the improved stove intervention was associated with 3.7 mm Hg lower SBP [95% confidence interval (CI), −8.1 to 0.6] and 3.0 mm Hg lower DBP (95% CI, −5.7 to −0.4) compared with controls. In the second study design, among 55 control subjects measured both before and after receiving chimney stoves, similar associations were observed.ConclusionThe between-group comparisons provide evidence, particularly for DBP, that the chimney stove reduces blood pressure, and the before-and-after comparisons are consistent with this evidence.

Highway proximity and black carbon from cookstoves as a risk factor for higher blood pressure in rural China

“…Our results are consistent with several intervention studies in Latin America that found a decrease in SBP (∼3-6 mmHg) in older women who switched from a traditional open fire cookstove to a less-polluting chimney stove (40,41). Although blood pressure is an important risk factor for cardiovascular diseases and overall global burden of disease (1), further research should assess the associations of BC with other health outcomes, including those in vulnerable populations like children.…”

Quantification of Indoor Air Pollution from Using Cookstoves and Estimation of Its Health Effects on Adult Women in Northwest Bangladesh

“…This theory calls for further evidential support by epidemiological study on cardiovascular risks of indoor air pollution. However, there exists support for influences of PM 2.5 on blood pressure (McCracken et al, 2007). If Smith and Peel's theory is accepted, then the RR of CVD for cooks using the BCSIR stove is approximately 1.5.…”

Evaluation of the effects of chronic biomass fuel smoke exposure on peripheral endothelial functions: an observational study

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“…Indoor effects of these products have been investigated and an increase in the incidence of chronic obstructive pulmonary disease, asthma, low birth weight, interstitial lung disease, lower respiratory tract infections and cataract was declared (2)(3)(4)(5)(6)(7)(8). Although there is a paucity of data on the association between cardiovascular disease and BMF, it has been shown that particulate air pollution leads to rapid and significant increases in fibrinogen, plasma viscosity, platelet activation and release of endothelins, which may indicate BMF as a considerable risk for cardiovascular health (9)(10)(11).…”