Homocysteine and the Risk of Cardiovascular Events and All-Cause Death in Elderly Population: A Community-Based Prospective Cohort Study

BACKGROUND: The association between homocysteine and cardiovascular diseases (CVD) and all-cause death was inconclusive. A community-based prospective cohort study was carried out in Beijing to evaluate this association in elderly population for more effective clinical prediction and primary prevention of CVD. PATIENTS AND METHODS: Participants were randomly selected from Beijing, China. Questionnaire survey, physical examinations, and laboratory tests were carried out to collect baseline information and investigate clinical characteristics. Each participant was predetermined to be followed by 5 years. CVD events and death were collected as primary variables. A Cox regression analysis was performed to assess the risk of CVD events, CVD death, and all-cause death contributed by homocysteine as well as some other risk factors. RESULTS: A total of 1257 participants with an average age of 69.16 years were enrolled in this study. After adjusting for confounders, the hazard ratios (HRs) and 95% confidence intervals of CVD event, CVD death, and all-cause death caused by intermediate-to-severe hyperhomocysteinemia as compared with normal homocysteine levels were 1.68 (95% CI 1.06–2.67), 1.97 (95% CI 0.95–4.29) and 2.02 (95% CI 1.26–3.24), respectively. Intermediate-to-severe hyperhomocysteinemia increased the risks of CVD event (HR 2.07, 95% CI 1.01–4.26) and all-cause death (HR 3.08, 95% CI 1.56–6.07) among male participants. However, the positive association was not statistically significant among female participants (HR 1.59, 95% CI 0.83–3.04 for CVD event and HR 0.90, 95% CI 0.52–6.07 for all-cause death). Every 5μmol/L increment in homocysteine concentration was shown to be associated with a 4% (HR 1.04, 95% CI 1.01–1.07) and 5% (HR 1.05, 95% CI 1.01–1.07) higher risk of CVD events and all-cause death in all participants. There was no significant association between moderate hyperhomocysteinemia and the risk of the CVD events and all-cause death. CONCLUSION: Intermediate-to-severe hyperhomocysteinemia was significantly associated with CVD events and all-cause death in elderly population without a history of ischemia or congestive heart failure (CHF). The positive association was pronounced among males.