Factors Associated With Isolated Right Heart Failure in Women

Abstract

Background: Small observational studies have found that isolated right heart failure (IRHF) is prevalent among women of sub-Saharan Africa. Further, several risk factors for the development of IRHF have been identified. However, no similar studies have been conducted in Kenya. Objective: We hypothesized that specific environmental exposures and comorbidities were associated with IRHF in women of western Kenya. Methods: We conducted a case-control study at a referral hospital in western Kenya. Cases were defined as women at least 35 years old with IRHF. Control subjects were similarly aged volunteers without IRHF. Exclusion criteria in both groups included history of tobacco use, tuberculosis, or thromboembolic disease. Participants underwent echocardiography, spirometry, 6-min walk test, rest/exercise oximetry, respiratory health interviews, and human immunodeficiency virus (HIV) testing. Home visits were performed to evaluate kitchen ventilation, fuel use, and cook smoke exposure time, all surrogate measures of indoor air pollution (IAP). A total of 31 cases and 65 control subjects were enrolled. Surrogate measures of indoor air pollution were not associated with IRHF. However, lower forced expiratory volume at 1 s percent predicted (adjusted odds ratio [AOR]: 2.02, 95% confidence interval [CI]: 1.27 to 3.20; p¼0.004), HIV positivity (AOR: 40.4, 95% CI: 3.7 to 441; p<0.01), and self-report of exposure to occupational dust (AOR: 3.9, 95% CI: 1.14 to 14.2; p ¼ 0.04) were associated with IRHF. In an analysis of subgroups of participants with and without these factors, lower kitchen ventilation was significantly associated with IRHF among participants without airflow limitation (AOR: 2.63 per 0.10 unit lower ventilation, 95% CI: 1.06 to 6.49; p ¼ 0.04), without HIV (AOR: 2.55, 95% CI: 1.21 to 5.37; p ¼ 0.02), and without occupational dust exposure (AOR: 2.37, 95% CI: 1.01 to 5.56; p ¼ 0.05). Conclusions: In this pilot study among women of western Kenya, lower kitchen ventilation, airflow limitation, HIV, and occupational dust exposure were associated with IRHF, overall or in participant subgroups. Direct or indirect causality requires further study.