Posted: Dec 20, 2012 10:01 PM
Dec. 20, 2012 -- The most widely prescribed sleeping pills do help people get to sleep, but maybe not only because of the medicine, a new study suggests.
But at least one sleep expert disagrees with that conclusion.
The researchers conclude that these drugs improved people's ability to fall asleep compared to a placebo; however, the size of the effect was small.
Side effects of sleeping pills can include memory loss, daytime sleepiness, and increased risk of falls, and researchers say the drugs may be especially risky for older patients.
But a sleep specialist says the study does little to convince him that the drugs -- used by millions of people worldwide -- are less effective than studies suggest.
"The fact is that it is difficult to measure the effectiveness of sleep medications in studies. Patients take them and they either work or they don't."
"I don't see how these researchers can come to the conclusion that 50% of the effect of these sleeping pills are due to the placebo effect," says David Volpi, MD, of the sleep disorders division of Lenox Hill Hospital in New York.
The new analysis, published in BMJ, was a collaborative effort by scientists from the University of Lincoln in the U.K., Harvard University, and the University of Connecticut.
It included data from 13 trials submitted by pharmaceutical companies to the FDA for approval of eszopiclone (Lunesta), zaleplon (Sonata), and zolpidem (Ambien).
The studies focused on the time it took to fall asleep after taking the drug.
The new analysis shows that sleeping pill users fell asleep about 22 minutes faster than non-users. Those on placebo fell asleep after 42 minutes.
According to researcher A. Niroshan Siriwardena, MD, PhD, one of the major limitations of studies submitted to the FDA is that they failed to measure some of the most troubling issues associated with sleep disturbances including total sleep time, waking after falling asleep, and daytime sleepiness.
"Because the studies didn't measure these things, we cannot say whether these drugs are useful for improving these outcomes," he says.
Volpi says prescription sleeping pills are often used by patients for much longer than they were originally intended.
These drugs are overprescribed and patients stay on them too long, he says. "It's not unusual to see patients who have been on them for years."
Siriwardena and Volpi also agree that other types of sleep treatments, such as talk therapy, are underutilized and could be used to help many more patients with sleep issues.
"There are so many things you can try for sleep problems, and cognitive behavioral therapy is one of the best things patients can do to get off of these medication," Volpi says says.
The manufacturer of Ambien was contacted but declined to comment. The makers of Lunesta and Sonata were contacted but did not respond before publication.