Early Menarche and Ischemic Stroke Risk Among Postmenopausal Women

SummaryBackgroundResults from previous studies regarding relationships between age at menarche and cardiovascular disease remain controversial. This study investigated the association between endogenous estrogen exposure and ischemic stroke risk.MethodsA total of 189 ischemic stroke patients and 192 age-matched healthy postmenopausal women were recruited. Age at menarche and menopause and risk factors of ischemic stroke were recorded through structured questionnaires by well-trained research assistants. Lifetime estrogen exposure was calculated as the number of years between age of menarche and menopause.ResultsStudy subjects with a history of hypertension and diabetes mellitus have a 2.8- and 6.2-fold increased risk for ischemic stroke, respectively. In addition, study subjects with waist circumferences ≥ 80cm also have a 2.6-fold increased risk of ischemic stroke. Conversely, subjects who experienced menarche at an early age may have a significantly decreased risk of 0.3-fold for ischemic stroke. Moreover, there was a significant and joint protective effect for study subjects without any risk factors of ischemic stroke, including a history of hypertension and diabetes mellitus, late age at menarche, and shorter lifetime estrogen exposure; these subjects were found to have the lowest risk (0.03-fold) for the development of ischemic stroke.ConclusionOur study provides strong evidence that a significant joint protective effect was observed for patients who undergo early menarche, have longer estrogen exposure and no history of hypertension or diabetes mellitus on the risk of ischemic stroke.