By Pat Anson, Editor

Anti-anxiety drugs often prescribed to chronic pain patients increase the risk of dementia and Alzheimer's disease when used long term, according to clinicians with the American College of Osteopathic Neurologists and Psychiatrists.

Benzodiazepines --  also known as benzos -- include brand name prescription drugs such as Valium, Ativan, Klonopin and Xanax. They were approved by the U.S. Food and Drug Administration to treat psychiatric conditions, but are also prescribed "off label" to treat bipolar disorder, insomnia, post traumatic stress disorder, and chronic pain.

A Canadian study of 9,000 patients found those who had taken a benzodiazepine for three months or less had about the same dementia risk as those who had never taken one.

But taking benzos for three to six months raised the risk of developing Alzheimer's by 32 percent, and taking them for more than six months boosted the risk by 84 percent.

Similar results were found by French researchers studying more than 1,000 elderly patients.

"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," saidHelene Alphonso, DO, Director of Osteopathic Medical Education at North Texas University Health Science Center in Fort Worth.

The case for limiting the use of benzodiazepines is particularly strong for patients 65 and older, who are more susceptible to falls, injuries, accidental overdose and death when taking the drugs. The American Geriatric Society in 2012 labeled the drugs "inappropriate" for treating insomnia, agitation or delirium because of those risks.

"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. While correlation certainly isn't causation, there's ample reason to avoid this class of drugs as a first-line therapy," said Alphonso.

In its draft guidelines for the prescribing of opioid pain medication, the Centers for Disease Control and Prevention (CDC) recommends that opioids and benzodiazepines not be prescribed concurrently whenever possible. A CDC study found that about 80% of unintentional overdose deaths associated with opioids also involved benzodiazepines. Nearly 6,500 people died from overdoses involving benzodiazepines in 2010.

Opioids, benzodiazepines and muscle relaxants are all central nervous system depressants. Mixing the drugs is potentially dangerous because their interaction can slow breathing and raise the risk of an overdose death.

In a study of over 35,000 patient visits for acute and chronic pain, recently published in the journal Pharmacoepidemiology and Drug Safety,  researchers found that the prescribing of benzodiazepines was three to four times more likely when opioids were also prescribed.

Over a third of the patients prescribed opioids for chronic musculoskeletal pain were given a sedative. And patients with a history of psychiatric and substance abuse disorders were even more likely to be co-prescribed opioids and sedatives.

"Multi drug use is the trailing edge of the opioid epidemic," said Mark Sullivan, MD, a professor of psychiatry and behavioral sciences at the University of Washington School of Medicine. "We are making progress on decreasing opioid prescribing, but co-prescribing of opioids and sedatives has not decreased.

"Patients who are on long-term combined opioid and benzodiazepine therapy are often on a treadmill. They feel relief when they take their medications and withdrawal when they stop, so they continue this combined therapy, even though many function poorly and some will die as a result."

Over 50,000 visits to emergency rooms in 2011 involved a combination of benzodiazepines and opioids, according to the Substance Abuse and Mental Health Services Administration (SAMHSA)