They help many people sleep, or feel calmer or less anxious. But in older individuals, they also double the risk of car crashes, falls and broken hips.

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That's why the potent class of medications known as benzodiazepines now appear on international guidelines as drugs that few people over the age of 65 should take.

Yet a sizable percentage of adults in that age group still have an active prescription for one, according to new research from three countries that have made a special effort to reduce their use in recent years.

Currently, about 7 percent of older veterans in the United States have a benzodiazepine prescription, and the numbers are even higher in Canada and Australia, according to the study published in the Journal of the American Geriatrics Society.

There's been a steady decline in all such prescriptions since new guidelines came out earlier this decade, the research shows. And the number of older adults starting on the drugs for the first time has dropped even faster.

Despite these reductions, researchers note that continued use of the drugs indicates much more needs to be done to alert providers — as well as patients and families — to the hazards of benzodiazepines for older adults and the need for alternative treatments.

"This downward trend is definitely encouraging, in particular the trend in the new starts for these medications, because the easiest solution is to not start people on them at all," says Donovan Maust, M.D., M.S., an assistant professor of geriatric psychiatry at the University of Michigan Medical School.

Maust, who worked on the new study and for years has studied the risks of psychoactive drugs on older adults, notes that newer antidepressant medications and nondrug psychotherapy approaches have been shown to help ease many of the symptoms that often prompt doctors to prescribe benzodiazepines in the first place — but without the associated risks.

And, he adds, research has shown that patients who take a benzodiazepine to calm the effects of acute stress are actually more likely to develop post-traumatic stress disorder.

More about the study

An international group of authors including Maust and his colleagues looked at data from older adults treated in three different health care systems between 2010 and 2016: the U.S. Veterans Affairs health care system; the single-payer systems in Canada's most populous province, Ontario; and Australia.

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In all, the percentage of U.S. veterans ages 65 and older that were prescribed a benzodiazepine dropped from 9.2 percent in 2010 to 7.3 percent in 2016 — and the percentage newly started on the drugs for the first time dropped from 2.6 percent to 1.7 percent over the same period.

While this is encouraging, Maust notes that the veteran population likely has lower benzodiazepine use than the general U.S. population due to VA efforts to discourage their use.

Ontario, on the other hand, started with much higher prevalence: 18.2 percent of all older adults had a current prescription in 2010, declining to 13.4 percent by 2016. The province also made strides in reducing the percentage who started a prescription each year, from 6 percent to 4.4 percent.

Australia started off with the largest proportion of its over-65 population on a benzodiazepine prescription, at 20.2 percent in 2010. By 2016, that had declined to 16.8 percent. But the number of first-time prescriptions didn't go down much – from 7 percent to 6.7 percent.

Choosing wisely together

All three countries participate in Choosing Wisely International, an effort supported by the Commonwealth Fund to help countries emulate the Choosing Wisely initiative launched by the American Board of Internal Medicine Foundation that offers American doctors and patients dozens of evidence-based recommendations. Australia and Canada each have their own national initiatives.

In fact, benzodiazepine use by people over age 65 landed among the top 10 issues on which the Choosing Wisely International group chose to focus attention.

Jonathan Brett, MBBS, from the University of New South Wales in Sydney, and the study's lead author, notes "this analysis is the first publication of an international collaborative explicitly focused on the measurement of harmful or wasteful care."

Studying the use of the drugs in different countries was tricky because of the nature of data available from each national system, notes Maust, who is a member of the U-M Institute for Healthcare Policy and Innovation.

In the U.S. VA system, which shares one medical record system, educating providers about the risks of benzodiazepines in older patients, and to scrutinize prescriptions for them, is a more streamlined effort. 

In Ontario and Australia, the oldest patients had the highest rates of existing or new prescriptions, which other studies have suggested is also true for nonveteran older adults in the U.S. But in the VA system, the youngest group of older patients — those ages 65 to 74 — had higher benzodiazepine prescription numbers than the oldest veterans.

Since 2012, all benzodiazepines have been listed on the American Geriatrics Society's Beers Criteria, a list of medications that carry outsize risks for older adults. The U.S. Choosing Wisely recommendations against benzodiazepines were introduced in 2013.

Still, concerns about their use among older adults have been raised for over 20 years.

"When you consider that, it's disappointing that new use isn't dropping more," says Maust. "We need to bend the curve further, with special focus on those who have never been prescribed these medications before because the greatest risk of fall is in the first few weeks after starting on one of these drugs.

"And if you don't become a new user, you can't become a chronic user."

The research team included U-M and VA researcher Eve Kerr, M.D., MPH, who has worked with the broader Choosing Wisely initiative, as well as colleagues from the Centre for Big Data Research in Health at the University of New South Wales and the Menzies Centre for Health Policy at the University of Sydney and the Institute for Health System Solutions and Virtual Care at Women's College Hospital in Toronto, Ontario.