Abstract P399: Fasting Insulin Levels and Incidence of Hypertension, Stroke and Coronary Heart Disease: A Meta-analysis of Prospective Cohort Studies
Background: Insulin resistance is a precursor of numerous chronic diseases including cardiovascular diseases (CVD). Fasting insulin level is a suggested surrogate of insulin resistance. However, a systematic and quantitative assessment of published studies linking fasting insulin levels to CVD is unavailable.
Objective: We aimed to quantitatively summarize the literature on the associations between fasting blood insulin levels and risk of hypertension, stroke and coronary heart disease (CHD) by conducting a meta-analysis of prospective cohort studies.
Design: Relevant studies were identified by searching PubMed and EMBASE through September 2012. Additional information was retrieved through Google or a hand review of the reference from relevant articles. Prospective cohort studies that reported relative risks (RRs) and corresponding 95% CIs for the associations of interest were identified. Data were extracted independently by two investigators and summary estimates for the associations were obtained by using random-effects models.
Results: Of 20 included studies, 9 reported results on hypertension (25, 494 individuals and 4, 349 cases), 6 reported on stroke (22, 773 individuals and 905 cases), and 9 reported on CHD (24, 986 individuals and 1, 962 cases). Compared with those in the lowest quantile, the pooled RRs for individuals in the highest quantile of fasting blood insulin levels were 1.56 (95 % CI: 1.26-1.92) for hypertension, 1.84 (95 % CI: 1.22-2.78) for stroke, and 1.32 (95 % CI: 1.02-1.71) for CHD. Per 50 pmol / L increment in fasting insulin was significantly positively associated with hypertension (RR: 1.23; 95% CI: 1.15-1.30), stroke (RR: 1.18; 95% CI: 1.03-1.36), and CHD (RR: 1.15; 95% CI: 1.07-1.22). In stratified analysis of 3 cohort studies with available data on stroke subtypes, the pooled RRs (highest vs. lowest quantile) were 1.58 (95% CI: 1.25-2.01) for ischemic stroke and 3.70 (0.86-15.89) for hemorrhagic stroke.
Conclusions: Higher fasting insulin level or hyperinsulinemia was associated with increased risk of hypertension, stroke (particularly ischemic stroke) and CHD. This meta-analysis suggests that fasting blood insulin ascertainment may help clinicians to identify those who are at high risk of CVD. Further studies are warranted to examine if to reduce fasting insulin will lower cardiovascular risk.
- © 2013 by American Heart Association, Inc.