Women who take oestrogen supplements from before or at the start of menopause and continue with them for a few years have better preserved brain structure, which may reduce the risk of dementia.
Globally, one new person is affected by dementia every four seconds. In 2010, 36 million people were estimated to have dementia.
Now, findings in a doctoral thesis from the Norwegian University of Science and Technology (NTNU) show that oestrogen supplements can reduce the risk of dementia in women.
“Oestrogen supplements can have a positive effect against dementia if women start early enough with treatment,” says Carl Pintzka, a medical doctor and PhD candidate at NTNU.
The finding has been published in the journal Neurobiology of Aging.
A sample of 80 women who had used oestrogen supplements through menopause was compared with 80 women who had never used oestrogen supplements. All had participated in the Nord-Trøndelag Health Study (HUNT), a general population-based study in mid-Norway.
The brain shrinks with less oestrogen
Following menopause, womens’ oestrogen levels drop significantly compared to levels before menopause.
MRIs of the brains of the women in the study showed that those who had taken oestrogen supplements throughout menopause had a larger hippocampus. The hippocampus is one of the most important structures for memory and sense of place, and is one of the structures that is affected early in the progression of Alzheimer’s disease.
“We also examined the shape of the hippocampus and found that areas where hormone therapy had the greatest effect are the same areas that are affected by Alzheimer’s disease in its early stages,” says Pintzka.
Other studies have shown that women who start oestrogen supplements several years after menopause do not benefit from the same positive effect on the hippocampus.
Must start oestrogen from the late 40s
Pintzka’s findings show that boosting oestrogen levels increases the volume of the hippocampus. As of yet there are no drugs that stop or prevent the course of Alzheimer’s disease, and the focus has shifted towards strategies to prevent or delay the onset of dementia.
Successful strategies are thought to be those that increase brain volume, and that in particular preserve the hippocampus. The risk of dementia may therefore be reduced for women taking estrogen supplements around the time of menopause, according to Asta Håberg, a Professor of Neuroscience at NTNU and Pintzka’s supervisor.
Until 2002, many women in Norway and internationally took oestrogen supplements during and after menopause. The reasons for boosting oestrogen levels are to reduce hot flashes and osteoporosis and to prevent cardiovascular disease. Then the number of women taking supplements fell dramatically.