Stroke risk rises with HRT oestrogen level
4 October 2002
Women who start taking hormone replacement therapy (HRT) should be prescribed the lowest possible oestrogen dose to minimise their risk of experiencing ischaemic stroke, US researchers recommended.
The researchers conducted a case-control study of almost 3500 women aged 30-79 years, and found the risk of ischaemic stroke increased with oestrogen dose (Archives of Internal Medicine 2002; 162: 1954-60).
After adjusting for risk factors, women using 0.625 mg of oestrogen had a 1.4-fold increased risk of ischaemic stroke compared with women using a 0.3 mg dose.
Oestrogen doses greater than 0.625 mg were associated with a 2.4-fold increased risk.
'If this is true, it suggests we should start patients on the lowest dose of HRT that is effective and only increasing if symptoms persist,' Australasian Menopause Society president Dr Rod Baber said.
'We don't know why these things happen, but it's possible the dose correlation might suggest some prothrombotic effect of a high HRT dose early in therapy,' he said.
'The other possible culprit is elevated C-reactive protein.'
The researchers also found a 2-fold increased ischaemic and haemorrhagic stroke risk during the first 6 months of HRT use, compared with HRT use of longer duration.
Last Reviewed: 03 October 2002
- 1. Medical Observer Weekly 4/10/02
