A new study found that drugs commonly used to treat anxiety and insomnia are not associated with an increased risk of cognitive decline in older adults. The findings, published in The BMJ, directly contradict past research that has linked benzodiazepines to Alzheimer's disease and other forms of cognitive decline.

Benzodiazepines are a class of drugs often prescribed to reduce anxiety, panic disorders, insomnia, and prevent seizures. They are some of the most commonly prescribed medications in the United States — familiar names include Valium and Xanax — with about 9 to 12 percent of older adults in the U.S. reporting use. This class of drug received FDA approval in the 1960s and was believed to be a safer alternative to barbiturates. Since then, this class of drugs has been linked to cardiac arrhythmia, hypotension, and respiratory depression.

There is a lot of conflicting research out there regarding the health risks associated with these drugs. Some studies linked benodiazephine use with heightened risk of Alzheimer's disease by about 50 percent, while others suggested long-term use does not increase the risk of cognitive decline. Given the conflicting research results, many are unsure of the health effects associated with the drugs, which is why health professionals are advised to avoid prescribing benzodiazepine as primary treatment for anxiety and sleep problems.

“Given the enormous public health implications, a better understanding of the potential cognitive risks of cumulative benzodiazepine use is needed,” researchers said.

Researchers recruited 3,434 adults aged 65 and older who did not have dementia at the start of the study. These participants were followed for an average of seven years. Cognitive screening was carried out when participants entered the study and again every two years. Benzodiazepine use was assessed using computerized pharmacy data over a 10-year period.

During the study, only 797 participants — 23 percent — developed dementia, of whom 80 percent developed Alzheimer's disease. Researchers found no association between the highest level of benzodiazepine use and dementia or cognitive decline. However, they did find a small increased risk for dementia in people with low or moderate use of the drugs.

“Overall, out pattern of findings does not support the theory that cumulative benzodiazepine use at the levels observed in our population is causally related to an increased risk for dementia or cognitive decline,” researchers wrote.

Given the mixed results regarding the health risk associated with these tranquilizer drugs, healthcare providers are still advised to avoid benzodiazepines in older adults to prevent important adverse health outcomes, withdrawal and dependence.

Source: Gray S, Dublin S, Yu O, et al. Benzodiazepine Use and Risk of Incident Dementia or Cognitive Decline: Prospective Population Based Study. The BMJ. 2016.