Benzodiazepine use is a growing problem. The number of Americans using benzodiazepines increased from 8.1 million in 1996 to 13.5 million in 2013, and the total quantity of benzodiazepine prescriptions filled during that time more than tripled. Although the American Geriatrics Society has listed them for years as "Potentially Inappropriate Medications" because of the health risks they pose to those over the age of 65, benzodiazepines are still prescribed to almost 9 percent of elderly people. Even for younger people, benzodiazepines cause acute cognitive impairment, among other risks.
Increased risk of dementia is another major concern with long-term use of benzodiazepines. In a meta-analysis, heavy cumulative doses of benzodiazepines were associated with a risk of dementia and Alzheimer’s disease. Two other recent studies also suggested an association between benzodiazepine use and dementia, finding that heavy use increased risk of Alzheimer’s disease while occasional low-dose use did not.
But a recent study from Dr. Shelly Gray and colleagues at the University of Washington and the Group Health Research Institute reported different results. Dr. Gray and colleagues examined the pharmacy records of Seattle residents over the age of 65 to see how many benzodiazepine prescriptions were made over the previous 10 years. Participants were grouped by exposure: never users, light users (<30 total days of benzodiazepine prescriptions), medium users (31-120 days), and heavy users (>120 days). Gray and colleagues found that even heavy users were at no greater risk for dementia or Alzheimer’s disease than never users.
Why this study and another from last year run counter to prevailing evidence is unclear. Is there a difference in the study population—participants in the United States, Canada, the UK, or Taiwan? Is it an association with a particular benzodiazepine—Xanax versus Valium or Klonopin? While most studies agree that occasional low-dose use of benzodiazepines in younger people is not associated with dementia in later life, research on the risk of heavy use is somewhat mixed. Still, the evidence overall suggests an increasing risk with cumulative exposure.
Despite the risks, about a third of people over age 65 prescribed benzodiazepines are given long-term prescriptions. If you're among them, you may want to discuss other options with your doctor. You can learn more from the American Geriatric Society’s Choosing Wisely list.
We are also working on a report of the potential risks of benzodiazepines, which will thoroughly examine all the evidence. Our internal report written for scientific staff is available as a download.
Nick McKeehan is Assistant Director, Aging and Alzheimer's Prevention at the Alzheimer’s Drug Discovery Foundation. He served as Chief Intern at Mid Atlantic Bio Angels (MABA) and was a research technician at Albert Einstein College of Medicine investigating repair capabilities of the brain. He received a bachelor of science degree in biology from Purdue University, where he was awarded a Howard Hughes Scholarship. Mr. McKeehan also writes about the biotechnology industry for 1st Pitch Life Science.
Get the latest brain health news:
Can Some Sleep Medications Raise the Risk of Alzheimer’s Disease?