In contrast to the most recent report from the Women's Health Initiative (JAMA May 28 2003) a prior report on research conducted in Utah, USA and published in the JAMA in November 2002, provided evidence favouring a protective effect of long-term postmenopausal hormone therapy (HT) on the risk of developing Alzheimer's Dementia.

The difference between the two studies was that in the Women's Health Initiative study women over 65 years were newly commenced on estrogen plus progestin. In contrast women in the study from UTAH were reporting past HT use probably commenced at the time of their menopause and continued for many years. The discrepancies in these results add weight to the hypothesis that the timing in the initiation of HT may be an important determinant of the effects, and demonstrate that we still have much to learn in this area.

The UTAH study was a prospective analysis of dementia occurring in 1889 women, (and 1357 men) of mean age 74.5 years, living in a single county in Utah, USA. They were initially assessed in 1995-1997 and followed up in 1998-2000. Women were found to be at higher risk than men. In women, the risk in non-HT users was 7.2% (58 cases among 800 women), whilst in HT use it was 2.4% (26 cases amongst 1066 women), an absolute reduction in risk of 4.8%.

With more than 10 years use of HT, a woman's sex-specific increase in risk disappeared entirely, ie; her risk became equal to the risk observed in men.

A number of previous population studies have shown similar risk reduction. The limitation of this study is that it relies upon women recalling whether they have used hormone therapy in the past rather than upon documentation of use.

The strongest evidence for protection by HT against Alzheimer's would require a randomised-controlled trial.

The range of therapies available to treat the symptoms of menopause - diet, exercise, drug and alternative therapies all have their place. Hormone therapy is only one of many therapies available for women who are suffering symptoms of menopause - factors such as lifestyle, diet and exercise are also important, not only in terms of symptoms but also in terms of long-term health risk.

No two women are the same - and the treatment of the symptoms of menopause is very individual. Women should ensure that they talk through all the issues with their health practitioner to get the information they need to make the right personal decision for them.

JAMA Study

Hormone Replacement Therapy and Incidence of Alzheimer Disease in Older Women The Cache County Study  Peter P. Zandi; Michelle C. Carlson; Brenda L. Plassman; Kathleen A. Welsh-Bohmer; Lawrence S. Mayer; David C. Steffens; John C. S. Breitner; for the Cache County Memory Study Investigators 
(JAMA. 2002;288:2123-2129)

Hormone Therapy and Risk of Alzheimer Disease - A Critical Time
Susan M. Resnick; Victor W. Henderson
(Editorial from JAMA)
(JAMA. 2002;288:2170-2172)

 Content updated September  4, 2003