Age At Menarche, Age At Menopause, Reproductive Years and Risk of Fatal Stroke Occurrence Among Chinese Women: The Guangzhou Biobank Cohort Study

Abstract

Background The relationship between women’s reproductive characteristics and stroke events is unclear. We aimed to investigate age at menarche, age at menopause and number of reproductive years in relation to fatal stroke occurrence in the Guangzhou Biobank Cohort Study. Methods In total, 16504 postmenopausal women without stroke, heart disease or a cancer history at baseline were included and followed up for a median of 12.0 years. After review of available records, 222 stroke deaths were recorded. Cox proportional hazards regression was used to assess the associations between the risk of fatal stroke occurrence and age at menarche, age at menopause and number of reproductive years. Results In the whole cohort, compared with those aged 15 years at menarche, women aged 17 years at menarche had an increased risk for fatal stroke (adjusted hazard ratio [aHR] = 1.83, 95% confidence interval (CI) 1.10–3.05) and fatal haemorrhagic stroke (HR = 2.65, 95% CI 1.14–6.18), and women aged ≥ 18 years at menarche had an increased risk for fatal stroke (HR = 1.66, 95% CI 1.03–2.70) and fatal ischaemic stroke (HR = 2.01, 95% CI 1.01–3.99). Among postmenopausal women born before 1940, women aged < 43 years at menopause had an increased risk for fatal stroke (HR = 1.97, 95% CI 1.05–3.69) compared with those aged 51–52 years at menopause. Additionally, in the whole cohort, women with ≤ 28 reproductive years had an increased risk for fatal stroke (HR = 1.91, 95% CI 1.28–2.86) and fatal ischaemic stroke (HR = 2.26, 95% CI 1.26–4.05) compared with those with 32–34 reproductive years; postmenopausal women born before 1940 had a similar risk for fatal stroke and fatal ischaemic stroke. Conclusions Older age at menarche, younger age at menopause and fewer reproductive ages were related to an increased risk of fatal stroke in postmenopausal women.

Age at menopause and risk of ischemic stroke: a systematic review and meta-analysis

“…Table 2 shows the summary estimates from the meta-analysis of the association between age at menopause and ischemic stroke. Of these 10 studies, 5 studies defined menopausal age before 45 years old as early menopause [16][17][18][19][20] , The other 5 studies defined menopausal age before 49, 47, 43, 42, and 40 years old as early menopause, respectively [21][22][23][24][25] (Table1). For the age at menopause and the incidence of ischemic stroke, Table2B,2C,2D demonstrate the risk of menopause and ischemic stroke for women whose age at menopause was before 45, 49 and 43 years, respectively.…”

“…There are two articles, one defines menopause age before 43 years old as early menopause [23] , and the other defines menopause age before 49 years old as early menopause [26] . Considering that there are cases of premature menopause due to iatrogenic factors or delayed menopause due to the use of hormone replacement therapy in the age at menopause group between 43 and 49 years old, there may be both early menopause and delayed menopause relative to the body's physiological menopause age.…”