Long-term use of benzodiazepine medications, widely used to ease anxiety and promote sleep, is tied to an increased risk of developing Alzheimer’s, a study of elderly men and women living in Canada found. But whether or not these drugs are directly linked to Alzheimer’s and hasten its onset remains unknown.
Doctors commonly prescribe benzodiazepines, sold under brand names like Valium, Xanax and Ativan, for relief of anxiety, agitation and insomnia. They are “indisputably valuable tools for managing anxiety disorders and transient insomnia” the authors of the study write. But, they advise, treatments “should be of short duration and not exceed three months,” particularly in older men and women.
For the study, the researchers, from France and Canada, analyzed prescription drug data from the Quebec health insurance program database. Over a period of at least six years, they tracked the onset of Alzheimer’s among nearly 9,000 Canadians older than 66 who were taking benzodiazepines.
During that time, 1,796 of the men and women being followed developed Alzheimer’s disease. They compared them with 7,184 seniors in the database who did not develop dementia. The researchers sought to adjust for symptoms like anxiety, depression and insomnia, which may be early signs of impending Alzheimer’s, by ruling out anyone who was diagnosed with Alzheimer’s within five years of the study’s start.
They found that those who had taken benzodiazepines for at least three months were at increased risk of developing Alzheimer’s disease. The longer someone took the drugs, and the higher the dose they took, the greater the likelihood of developing Alzheimer’s.
The findings, published in the British medical journal BMJ, suggest a correlation between benzodiazepine use and Alzheimer’s. But they cannot prove a cause-and-effect relationship. Chronic anxiety is known to increase the risk of developing dementia, and in some cases might actually be part of a pre-dementia phase of Alzheimer’s. Also, many people in the study who took anxiety-relieving drugs did not develop Alzheimer’s. And some people who were not taking these medications did develop Alzheimer’s.
Still, the authors urge caution for anyone taking these drugs for three months or longer. Benefits and potential risks must be carefully weighed, they say, particularly in older people.
Benzodiazepines are known to contribute to confusion and a greater risk of falls in the elderly. That’s one reason the American Geriatrics Society updated its list of inappropriate drugs for older adults in 2012 to include benzodiazepines.
Yet almost half of older adults continue to use these drugs. As a result, many may experience problems with memory and thinking related to the drugs.
The authors of the current study say their study cannot prove that benzodiazepines cause Alzheimer’s disease. It may be that symptoms like anxiety and insomnia appear many years before Alzheimer’s is formally diagnosed, leading doctors to prescribe these drugs at increased rates in those destined to get the disease. But, the researchers suggest, long-term use of the drugs may also alter receptors in the brain, making it more vulnerable to the ravages of Alzheimer’s. Older people who suffer from anxiety might try an antidepressant drug of the SSRI type (selective serotonin reuptake inhibitor). SSRIs can relieve anxiety and generally do not lead to confusion.
“Our study reinforces the suspicion of an increased risk of Alzheimer type dementia among benzodiazepine users, particularly long term users,” the authors write. “As stated in international guidelines, treatments should be of short duration and not exceed three months.”
Source: Sophie Billioti de Gage, Yola Moride, Thierry Ducruet, et al: “Benzodiazepine Use and Risk of Alzheimer’s Disease Case-Control Study.” BMJ, Sept. 9, 2014