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passages: document
passages: Intervention to lower household wood smoke exposure in Guatemala reduces ST-segment depression on electrocardiograms . BACKGROUND A large body of evidence suggests that fine particulate matter ( PM ) air pollution is a cause of cardiovascular disease , but little is known in particular about the cardiovascular effects of indoor air pollution from household use of solid fuels in developing countries . RESPIRE ( Randomized Exposure Study of Pollution Indoors and Respiratory Effects ) was a randomized trial of a chimney woodstove that reduces wood smoke exposure . OBJECTIVES We tested the hypotheses that the stove intervention , compared with open fire use , would reduce ST-segment depression and increase heart rate variability ( HRV ) . METHODS We used two complementary study designs : a ) between-groups comparisons based on randomized stove assignment , and b ) before-and-after comparisons within control subjects who used open fires during the trial and received chimney stoves after the trial . Electrocardiogram sessions that lasted 20 hr were repeated up to three times among 49 intervention and 70 control women 38-84 years of age , and 55 control subjects were also assessed after receiving stoves . HRV and ST-segment values were assessed for each 30-min period . ST-segment depression was defined as an average value below -1.00 mm . Personal fine PM [ aerodynamic diameter ≤ 2.5 μm ( PM₂.₅ ] exposures were measured for 24 hr before each electrocardiogram . RESULTS PM₂.₅ exposure means were 266 and 102 μg/m³ during the trial period in the control and intervention groups , respectively . During the trial , the stove intervention was associated with an odds ratio of 0.26 ( 95 % confidence interval , 0.08-0.90 ) for ST-segment depression . We found similar associations with the before-and-after comparison . The intervention was not significantly associated with HRV . CONCLUSIONS The stove intervention was associated with reduced occurrence of nonspecific ST-segment depression , suggesting that household wood smoke exposures affect ventricular repolarization and potentially cardiovascular health .
entities: 2108
entities: Intervention_Other
entities: chimney woodstove
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entities: Intervention_Other
entities: stove intervention
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entities: Intervention_Other
entities: open fire
entities: 2111
entities: Intervention_Other
entities: stove
entities: 2112
entities: Intervention_Other
entities: open fires
entities: 2113
entities: Intervention_Other
entities: chimney stoves
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entities: Intervention_Other
entities: stoves .
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entities: Outcome_Physical
entities: ST-segment depression
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entities: Outcome_Physical
entities: ST-segment depression
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entities: Outcome_Physical
entities: heart rate variability ( HRV ) .
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entities: Outcome_Physical
entities: HRV and ST-segment values
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entities: Outcome_Physical
entities: ST-segment depression
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entities: Participant_Sample-size
entities: 49
entities: 2121
entities: Participant_Sample-size
entities: 70
entities: 2122
entities: Participant_Age
entities: 38-84 years of age
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entities: Participant_Sample-size
entities: 55