Objective: This study aimed to evaluate the combined effects of family history of cardiovascular diseases (FHCVD) and heart rate on ischemic stroke incidence among Inner Mongolians in China.
Methods: A prospective cohort study was conducted among 2589 participants aged 20 years and older from Inner Mongolia, China. The participants were divided into four groups according to status of FHCVD and heart rate and followed up from June 2002 to July 2012. Cox proportional hazards models were used to evaluate the combined effects of FHCVD and heart rate on the incidence of ischemic stroke.
Results: A total of 76 ischemic stroke occurred during the follow-up period. The observed ischemic stroke cases tended to be older and male, and had higher prevalence of smoking, drinking, hypertension and FHCVD as well as higher systolic and diastolic blood pressures at baseline compared with those who did not experience ischemic stroke. Age- and gender-adjusted hazard ratio (95% confidence interval) of ischemic stroke in the participants with both FHCVD and heart rate ≥ 80 were 2.89 (1.51-5.53), compared with those without FHCVD and heart rate < 80. After multiple adjustment, the association between ischemic stroke risk and both FHCVD and heart rate ≥ 80 remained statistically significant (hazard ratio, 2.47; 95% confidence interval: 1.22-5.01).
Discussion: Our main finding that participants with both FHCVD and faster heart rate have the highest risk of ischemic stroke suggests that faster heart rate may increase the risk of ischemic stroke among people with FHCVD.
Keywords: Family history of CVD; Heart rate; Ischemic stroke.