Women who start hormone therapy within five years of menopause may reduce their risk of developing Alzheimer’s disease, according to a new study published today in Neurology, the medical journal of the American Academy of Neurology.
Data from the study suggests women starting hormone treatment within 5 years of menopause may decrease their chances of getting the neurological disease by up to 30%.
Researchers in the study followed 1,768 women, ages 65 and older, for 11 years. The women provided a history of their hormone therapy use and the date when they experienced the beginning of menopause.
The number of women who used hormone therapy consisting of estrogen alone or in combination with a progestin was 1,105. During the study, 176 women developed Alzheimer’s disease dementia, including 87 of the 1,105 women who had taken hormone therapy compared to 89 of the 663 others.
The risk was unchanged among other hormone users who had begun treatment more than five years after menopause, but a higher risk of dementia was observed among women who had started a combined therapy of estrogen and progestin when they were at least 65 years old.
The findings add to a growing amount of evidence that suggests hormone treatments taken around the time of menopause may not only help minimize night sweats and hot flashes, but also help prevent Alzheimer’s disease.
“Our results suggest that there may be a critical window near menopause where hormone therapy may possibly be beneficial,” said Peter Zandi of Johns Hopkins in a statement.
Zandi, one of the study’s leaders, and his colleagues decided to investigate whether the timing of starting hormone replacement therapy had any effect.
Their findings come from the Cache County Study on Memory, Health, and Aging, a study backed by the National Institute on Aging that has been following nearly all of the residents of Cache County, Utah, over age 65 since the study began in 1995.
There was no change in the risk among other hormone users who had begun treatment more than five years after menopause, but they did find a higher risk of dementia among women who started combined estrogen and progestin at age 65 or older.
Zandi said the study findings support that earlier treatment with hormones may be beneficial while later treatment may be harmful.
“It doesn’t prove the hypothesis,” said Zandi, “But it does suggest there might be something to that merits further investigation.”