Cardiovascular disease mortality based on verbal autopsy in low- and middle-income countries: a systematic review

Objective: To conduct a systematic review of verbal autopsy studies in low- and middle-income countries to estimate the fraction of deaths due to cardiovascular disease. Method: We searched MEDLINE®, Embase® and Scopus databases for verbal autopsy studies in low- and middle-income countries that reported deaths from cardiovascular disease. Two reviewers screened the studies, extracted data and assessed study quality. We calculated cause-specific mortality fractions for cardiovascular disease for each study, both overall and according to age, sex, geographical location and type of cardiovascular disease. Findings: We identified 42 studies for inclusion in the review. Overall, the cardiovascular disease cause-specific mortality fractions for people aged 15 years and above was 22.9%. This fraction was generally higher for males (24.7%) than females (20.9%), but the pattern varied across World Health Organization regions. The highest cardiovascular disease mortality fraction was reported in the Western Pacific Region (26.3%), followed by the South-East Asia Region (24.1%) and the African Region (12.7%). The cardiovascular disease mortality fraction was higher in urban than rural populations in all regions, except the South-East Asia Region. The mortality fraction for ischaemic heart disease (12.3%) was higher than that for stroke (8.7%). Overall, 69.4% of cardiovascular disease deaths were reported in people aged 65 years and above. Conclusion: The burden of cardiovascular disease deaths outside health-care settings in low- and middle-income countries is substantial. Increasing coverage of verbal autopsies in these countries could help fill gaps in cardiovascular disease mortality data and improve monitoring of national, regional and global health goals.