Researchers in Finland have found no strong evidence of an association between hormone therapy and the risk of Alzheimer’s disease. The study, published today in the journal Neurology, adds to existing research into the effects of the treatment, which has previously been linked to changes in Alzheimer’s risk.
Hormone therapy is commonly offered to help relieve symptoms of the menopause. The treatment increases the levels of hormones like oestrogen, and the course of treatment can vary considerably from person to person. Previous research into a possible link with Alzheimer’s risk has shown mixed results with some observational studies linking the treatment to a reduced risk of Alzheimer’s, but clinical trials indicating that it could increase the risk of the disease. Other studies have suggested that risk varies depending on the type and dose of hormones used, as well as when people receive the therapy.
The researchers studied the medication records of 8,195 women who had provided detailed information about their health and lifestyle every five years from 1989 to 2009. They looked to see if there was an association between people who had received hormone therapy and those who went on to be prescribed medications for Alzheimer’s. Records of which people received hormone therapy were only available from 1995, so researchers also used questionnaires to get information about prior use of the treatment.
Analysing the information available in the records, the researchers did not find a link between the use of hormone therapy and Alzheimer’s disease, regardless of how long the participants had used hormone therapy. When they looked at the self-reported information about hormone therapy, they found an association between those who reported taking the treatment for more than 10 years and a reduced risk of Alzheimer’s.
Dr Rosa Sancho, Head of Research at Alzheimer’s Research UK, said:
“Studies like this one, that take advantage of information held in the medical records of large groups of people, can be useful in highlighting potentially important trends and risk factors for different diseases. In this case, these records showed no apparent link between hormone therapy and Alzheimer’s risk. While there was some indication of a reduction in risk for people who received this treatment for more than 10 years, this finding was based on people’s own recollection of their medical history which can be incomplete or inaccurate.”
“There is ongoing research into the role that hormones might play in diseases like Alzheimer’s, and previous studies of the effects of hormone therapy have been mixed. The findings from this study need to be considered in the context of existing research and other data as it emerges. Anyone who is concerned about the effects of hormone therapy should speak to their doctor.”