Several common drugs used to treat psychiatric disorders have been found to greatly increase a person’s risk of developing dementia. In their new study, clinicians from the American College of Osteopathic Neurologists and Psychiatrists found a substantial body of evidence linking benzodiazepines to Alzheimer's disease and other forms of cognitive decline.

Benzodiazepines are a class of drugs that affect the central nervous system and are often used to reduce anxiety, panic disorders, insomnia, and prevent seizures. The most common forms on the market now are Valium, Ativan, Klonopin, and Xanax, which were first approved in the 1960s as a safer alternative to barbiturates. Since then, benzodiazepines have been linked to a multitude of adverse effects, including respiratory depression, slowed heart rate, cardiac arrhythmias, and hypotension.

New psychiatric protocols dictate that physicians should not prescribe benzodiazepines as a primary treatment for insomnia, anxiety, post-traumatic stress disorder, and obsessive-compulsive disorder. However, some physicians continue to prescribe these drugs for prolonged periods, despite evidence suggesting that the longer a patient is on this medication, the greater their chance of developing dementia or Alzheimer's.

“Current research is extremely clear and physicians need to partner with their patients to move them into therapies, like anti-depressants, that are proven to be safer and more effective,” said Dr. Helene Alphonso, director of Osteopathic Medical Education at North Texas University, in a recent press release.

For their study, the researchers looked at existing evidence about benzodiazepines' link to dementia. One of the studies they looked at comprised 9,000 elderly Canadian patients prescribed the class of drugs for certain periods of time. The researchers ultimately found that those who took benzodiazepines for three months or less had the same risk of developing dementia as those who never took the drug before. However, when three months extended to six, the risk of developing Alzheimer's increased by 32 percent. And any time over six months increased risk to 84 percent. Alphonso's team also observed similar results in a French study looking specifically at more than 1,000 elderly patients.

In light of the team's findings, Alphonso cautions that benzodiazepine use in adults 65 and older must be limited because this group is especially prone to falls, injuries, and accidental overdose when prescribed the medication. The study also notes that the American Geriatric Society labeled the drug an “inappropriate” treatment for insomnia, agitation, and delirium.

“It's imperative to transition older patients because we're seeing a very strong correlation between use of benzodiazepines and development of Alzheimer's disease and other dementias,” Alphonso said. “While correlation certainly isn't causation, there’s ample reason to avoid this class of drug as a first-line therapy.”

Source: Alphosno H, et al. American Osteopathic Association OMED 2015 meeting.