Benzodiazepines are drugs that are commonly prescribed to combat anxiety, or as sedatives and muscle relaxants. They include Xanax, Librium, Valium, and Halcion, and several others. We ve known the up-and-downsides of such drugs for many years, as well as their addictive tendencies. But a new study provides concern that we might need to add another risk to that list.
The investigators, led by Dr. Bernard Begaud of the University of Bordeaux, France, performed a case-control study seeking evidence of a possible association between Alzheimer s Disease (AD) and use of benzodiazepines. Performing what is known as a case-control study, they examined the past use of these drugs (by analyzing medical records) of nearly 1800 AD patients, and compared that use to that of 7000 similar people who had not been diagnosed with AD. The investigators considered both short-acting and long-acting benzodiazepines.
According to a report in the Los Angeles Times, there was no increased risk of AD in participants over the age of 66 who took low-dose versions of the drugs, or used them briefly or infrequently. But individuals who took daily doses for 3-6 months over a five-year period were about 30 percent more likely to develop AD. And use of a daily dose for over six months had an 84 percent increased risk.
ACSH s Dr. Gil Ross had this comment: The fact that there seemed to be a dose-response effect of benzodiazepine use on AD may lend the appearance of credibility to the study. But it s not really time to start worrying. This type of study is prone to confounding it is virtually impossible to choose people who are really the same for each group. That s why case-control studies typically have many more participants in the control group than in the affected group. Such studies cannot prove a causal link between the variables being investigated here AD and a particular class of drugs. It is much more likely, given the lack of any biological thesis for such a cause-and-effect link, that people in the early-middle stages of AD-dementia became more upset, anxious, and developed sleep disorders requiring medication, than to posit that benzodiazepines contribute to causing AD.