Sex hormone does not influence ischaemic stroke risk in postmenopausal women
There appears to be no role for sex hormones in mediating the risk of ischaemic stroke in postmenopausal women, a study reports.
The study estimated associations between plasma sex hormone levels and ischaemic stroke risk, by exogenous hormone therapy (HT) status, in a nested case-control study of postmenopausal women from the NHS (Nurses’ Health Study). The analysis included 419 ischaemic stroke patients and 419 matched controls.
Researchers measured plasma oestradiol and testosterone levels using liquid chromatography tandem mass spectrometry. They assayed SHBG (sex hormone-binding globulin) by electrochemiluminescence immunoassay.
Compared with never/past users, current HT users had different hormone profiles. There were no clear linear trends observed between the risk of ischaemic stroke and either oestradiol (total or free) levels or the oestradiol/testosterone ratio among current users (ptrend>0.1) and never/past users (ptrend>0.6).
Among both current and never/past users, the associations between ischaemic stroke and some of the sex hormones differed by body mass index (BMI) categories (pinteraction≤0.04). In the group of women with a BMI <25 kg/m2 for instance, the risk of ischaemic stroke was elevated among current HT users with a higher oestradiol/testosterone ratio (ptrend=0.01) and among never/past users with higher levels of total and free oestradiol (ptrend≤0.04).
Testosterone and SHBG showed no association with ischaemic stroke among current or never/past users. The findings should be replicated in additional larger studies, the researchers said.