Acute coronary syndrome and use of biomass fuel among women in rural Pakistan: a case-control study.

Three billion people use biomass fuel for cooking and heating globally. We assessed the association between acute coronary syndromes (ACS) and use of biomass fuel for cooking. We conducted a case-control study among women living in defined areas that were served by two tertiary care hospitals. A total of 364 women admitted to cardiac care units with ACS were compared with 727 controls, individually matched for age, who were inpatients at the same hospitals with a miscellany of diagnoses. Exposure to biomass fuel and other risk factors was ascertained through a questionnaire and assessed by conditional logistic regression. After adjustment, risk of ACS was elevated in women who had ever used biomass for cooking. In comparison with never users, the odds ratio for those who currently cooked with biomass was 4.8 (95% confidence interval 1.7, 13.8). However, among those who had ever used biomass, there was no decline in risk with time since last exposure. The study found increased risk of ACS from use of biomass for cooking. However, full benefits from interventions may not accrue in short term.