Older adults taking psychiatric medications, such as Valium or Xanax, may be at increased risk of dementia, a new French study suggests.
In the reports, adults older than 65 who took drugs known as benzodiazepines were 50 percent more likely to develop dementia over a 15-year period, compared with those who did not take the drugs.
Benzodiazepines are widely prescribed medications, used to treat symptoms of anxiety and sleep disorders.
The study findings held true even when taking into account other factors that may affect people's dementia risk, such as age, gender, diabetes and early signs of dementia. The researchers also accounted for some factors that lead people to start taking benzodiazepines in the first place.
Researchers caution that the study only found an association between the drugs and dementia, and not a direct cause-and-effect link.
However, the findings agree with those of several earlier studies looking at the link between benzodiazepines and dementia. Use of the medications has also been tied to other serious events in older adults, such as falls.
"Considering the extent to which benzodiazepines are prescribed and the number of potential adverse effects of this drug class in the general population, [their] indiscriminate, widespread use should be cautioned against," the researchers said.
Whenever possible, use of the drugs should be limited to just a few weeks, the researchers said. Currently, despite evidence that the drugs work only over short periods, many people take them for years.
The study followed about 1,000 older adults living in France who, at the study's start, did not have dementia and were not taking benzodiazepines. Over the first five years of the analysis, 95 participants started taking benzodiazepines.
Fifteen years later, 253 cases of dementia were confirmed — 30 in benzodiazepine users and 223 in non-users. That puts the yearly rate of dementia among those taking benzodiazepines at 4.8 cases per 100 people, compared with 3.2 cases per 100 people in those who did not take the drugs.
The researchers noted that, in determining dementia risk, they were able to account for the possible effects of depression, which is associated with the development of dementia. However they were not able to determine whether anxiety and or sleep disorders, which may be early signs of dementia, played a role a in the results.
Future research should examine whether use of the drugs is linked to dementia in younger people, and whether the drug dosage affects the risk, the researchers said.
The study is published today (Sept. 28) in the British Medical Journal.
Pass it on: Use of drugs called benzodiazepines is linked with an increased risk of dementia in older people.
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