Increased stroke risk and hormone replacement therapy link evident

Hormone replacement therapy (HRT) is associated with an increased risk of stroke, especially ischaemic stroke, found a review of trials recently published by the British Medical Journal (BMJ).

These results support previous trials that have suggested a link between HRT and stroke.

Researchers Philip Bath, professor of stroke medicine, and Laura Gray, medical statistician at the Division of Stroke Medicine, Institute of Neuroscience, Queen's Medical Centre, University of Nottingham (UK) reviewed the evidence from 28 completed trials involving 39,769 individuals. They assessed the risk of stroke by type, severity, and outcome.

Hormone replacement therapy was associated with an overall 29% increase in the risk of stroke, especially ischaemic stroke (caused by an insufficient blood supply to the brain). The severity of stroke was also increased with hormone replacement therapy.

It remains unclear why HRT should increase ischaemic stroke and its severity when some previous studies have suggested it might have a protective effect, the authors stated. Yet, given these findings, HRT cannot be recommended for the primary or secondary prevention of stroke.

SOURCE: “Association between hormone replacement and subsequent stroke: a meta-analysis,” Philip M W Bath, Laura J Gray, BMJ, doi:10.1136/bmj.38331.655347.8F (7 January 2005).