Homocysteine, hypertension, and risks of cardiovascular events and all-cause death in the Chinese elderly population: a prospective study

BACKGROUND Increased homocysteine levels are associated with the risk of cardiovascular disease (CVD) and death. However, their prevention has not been effective in decreasing CVD risk. This study investigated the individual and combined associations of hyperhomocysteinemia and hypertension with incident CVD events and all-cause death in the Chinese elderly population without a history of CVD. METHODS This prospective study was conducted among 1,257 elderly participants (mean age: 69 years). A questionnaire survey, physical examinations, and laboratory tests were conducted to collect baseline data. Hyperhomocysteinemia was defined as homocysteine level >= 15 mu mol/L. H-type hypertension was defined as concomitant hypertension and hyperhomocysteinemia. Multivariate Cox regression analysis was used to evaluate individual and combined associations of hyperhomocysteinemia and hypertension with the risks of incident CVD events and all-cause death. RESULTS Over a median of 4.84-year follow-up, hyperhomocysteinemia was independently associated with incident CVD events and all-cause death. The hazard ratios (HRs) were 1.45 (95% CI: 1.01-2.08) for incident CVD events and 1.55 (95% CI: 1.04-2.30) for all-cause death. After adjustment for confounding factors, H-type hypertension had the highest HRs for incident CVD events and all-cause death. The fully adjusted HRs were 2.44 for incident CVD events (95% CI: 1.28-4.65), 2.07 for stroke events (95% CI: 1.01-4.29), 8.33 for coronary events (95% CI: 1.10-63.11), and 2.31 for all-cause death (95% CI: 1.15-4.62). CONCLUSIONS Hyperhomocysteinemia was an independent risk factor, and when accompanied by hypertension, it contributed to incident CVD events and all-cause death in the Chinese elderly population without a history of CVD.