Body mass index and stroke mortality by smoking and age at menopause among Korean postmenopausal women

Abstract

BACKGROUND AND PURPOSE: The association between body mass index and mortality caused by subtypes of stroke among postmenopausal women in terms of smoking status and age at menopause remains controversial.

METHODS: The data were derived from a cohort study of 3321 with 17.8 years of follow-up (1985 to 2002). Hazard ratios (HRs) and 95% CIs for strokes as related to body mass index were estimated by Cox proportional hazard models adjusted for age, hypertension, smoking, drinking, occupation, education, self-reported health, and age at menopause. A stratified analysis was conducted by age at menopause and smoking status.

RESULTS: The obese group (body mass index >or=27.5 kg/m(2)) had higher risks of total stroke mortality (HR, 1.59; 95% CI, 1.05 to 2.42) and hemorrhagic stroke mortality (HR, 2.91; 95% CI, 1.37 to 6.19) than the normal weight group (18.5<or= body mass index <23.0). Among ever smokers, the obese group showed significantly increased risks of total stroke mortality (HR, 2.33; 95% CI, 1.00 to 5.43) and ischemic stroke mortality (HR, 7.21; 95% CI, 1.18 to 44.3). Obesity had more effect on stroke mortality among women who experienced menopause at age <50 than women with age >or=50. For the obese group of the former, the HR of total stroke was 2.04 (95% CI, 1.25 to 3.34) and that of hemorrhagic stroke 6.46 (95% CI, 2.42 to 17.25).

CONCLUSIONS: In this prospective study, obesity raised the risks of total stroke mortality and hemorrhagic stroke mortality among Korean menopausal women. It was more evident with women who experienced menopause at age <50. The obese group of ever smokers was at an increased risk of ischemic stroke mortality.