Family history, waist circumference and risk of ischemic stroke: A prospective cohort study among Chinese adults

BACKGROUND AND AIMS: The associations between genetic factors and waist circumference (WC) with stroke risk have been evaluated in Western studies. However, evidence of this association has rarely been reported in the Chinese population. This study aimed to evaluate the association between WC and family history of stroke (FHS) with ischemic stroke (IS) risk among Chinese adults and to further explore the potential interaction of these associations. METHODS AND RESULTS: The China Kadoorie Biobank (CKB) study recruited 35,508 participants aged 30–79 years from the Qingdao urban area during 2004–2008. A total of 33,355 participants were included in study. Cox regression analysis was used to estimate the multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) for the independent and interactional associations between FHS and WC and IS risk. Participants with FHS had a 29% (HR = 1.29, 95% CI: 1.12–1.50) higher IS risk than those without FHS. Participants with excessive WC (85 cm for males and 80 cm for females) had a 78% (HR = 1.78, 95% CI: 1.51–2.10) higher IS risk than those with normal WC. The combined effect of FHS and excessive WC on IS was statistically significant (HR= 2.29, 95% CI: 1.84–2.86). The present study further found statistically significant multiplicative interactions of FHS and WC with IS risk (P (interaction) < 0.001). CONCLUSION: The present study indicated that FHS and WC were significantly associated with an increased risk of IS. The association between FHS and IS was associated with excessive WC.