Strokes are presently a leading cause of death and disability across the world. Related to brain injury following impaired blood flow, they can be caused by arterial occlusions, termed ischaemic strokes, or by bleeding following damage to the cerebral arteries, also known as haemorrhagic strokes.
Patient sex has been shown to be a significant risk factor, affecting the prevalence and personal impact of strokes. Men experience a higher age-related rate of strokes, yet women experience more strokes in total and suffer from a greater loss to their quality of life after an event. However, the mechanisms responsible for mediating this relationship are poorly understood.
Sex hormones such as testosterone and oestrogen are responsible for determining most sexual differences during development and continue to be important risk factors in adulthood. For instance, high oestrogen levels are known to be cardioprotective in females. The drop in oestrogen during menopause partially accounts for the increased cardiovascular risk post-menopausal women experience. This has led to the development of hormone replacement therapy, a preventative treatment which protects from cardiovascular disease by administering exogenous oestrogen.
Pre-clinical research has suggested a similar relationship may exist between sex hormones and stroke. Testosterone is suspected to increase ischaemic stroke risk, while oestrogen appears to have a neuroprotective effect. Sex hormone binding globulin, a protein which attaches to sex hormones, is also believed to lower ischaemic stroke risk, possibly by binding to testosterone and preventing its neurotoxic effects.
Our study seeks to contribute the data gained from the UK Biobank to clarify our understanding of the association between each of these organic compounds and stroke. If successful, this study will likely lead to further research investigating the biochemistry responsible for this relationship, build a better understanding of the causes of stroke and potentially pave the way to new therapies for managing vulnerable patients.
We believe this project will require 18 months from initial analysis to completion.