Sleeping pills may raise risk of death: Study

By Dr. Ananya Mandal, MDFeb 29 2012

According to a U.S. study, people who take certain prescription sleeping pills even once in a while may be up to five times more susceptible to early death. In the U.S., an estimated six per cent to 10 per cent of adults used the drugs in 2010.

The findings, published in this week's issue of the journal BMJ Open, show the importance of not becoming dependent on sleeping pills to fight insomnia. To look for any associations between use of common hypnotics and increased mortality and cancer risks, the researchers compared death rates among 10,529 people who received prescriptions for sleeping pills and 23,600 others who did not but were similar in terms of age, physical health, income and other factors.

Results showed that people taking as few as 18 pills as year were 3.6 times more likely to die early than people who take no sleeping pills. Those taking 18 to 132 pills a year were up to five times more likely to die early. The study was done by Dr. Daniel Kripke of Scripps Clinic Viterbi Family Sleep Centre in La Jolla, Calif., and colleagues. Authors concluded that in 2010, hypnotics such as zolpidem, temazepam and eszopiclone may be associated with 320,000 to 507,000 excess deaths in the U.S. “These pills really seem too dangerous to use,” Kripke said in an interview.

“We were pretty startled by the findings,” says Robert Langer, one of the authors of the study. “Since we started trying to qualify the results of this analysis about a year ago, I'll tell you, my prescription bottle for Ambien has sat on the shelf unopened.”

“The meager benefits of hypnotics, as critically reviewed by groups without financial interest, would not justify substantial risks,” the study's authors said. “A consensus is developing that cognitive-behavioral therapy of chronic insomnia may be more successful than hypnotics.” Finding an association between sleeping pills and more deaths does not prove the pills are the cause, but the evidence points in that direction because the risk increased with higher doses, the researchers said.

The study did not say why the patients were prescribed the sleeping medications, whether the patients were evaluated by a sleep specialist, or whether they were also undergoing other types of treatment for any underlying health conditions -- all important factors when weighing an increased risk of death, said Dr. Steven Scharf, professor of medicine at the University of Maryland in Baltimore. “Most chronic conditions, including cancer, are associated with insomnia and mortality,” said Scharf. “Who knows what the cause here was?”

In the study, people on sleeping pills were more likely to have esophageal problems and peptic ulcers. The subjects were also more likely than cigarette smokers to be diagnosed with lymphomas, lung, colon and prostate cancers. It's also known that people who take sleeping pills may sometimes have residual dizziness the next day that may increase the risk of car collisions or falls. Sleeping pills also depress the respiratory system, which could reduce the drive to breathe if someone already has sleep apnea, authors say. It's also possible that an increase in depression among people who take sleeping pills could lead to harmful behavior and suicide.

Kripke said insomnia itself isn't dangerous in terms of mortality, but sleeping pills are. Sleeping pills are intended for people with acute insomnia, a sleep problem that lasts three weeks or less. But millions of people worldwide take the pills for months, said Dr. Jeffrey Lipsitz, medical director of the Sleep Disorders Centre in Toronto.

People taking sleeping pills should not stop them immediately without the supervision of the doctor who prescribed them because there may be untoward effects of stopping or changing abruptly Lipsitz warned.

“I think sleeping pills are helpful when there are short term stressors,” said Dr. Richard Colgan, associate professor in the department of family and community medicine at the University of Maryland School of Medicine. Sleeping pills can be helpful for those who work unusual shifts, and for those who travel across time zones, said Colgan.

Doctors say everyone could benefit from sleep hygiene - a set of behaviours such as going to bed at the same time all week, avoiding caffeine and stimulation from TV, electronics and strenuous activities before bedtime.

An estimated 50 to 70 million Americans suffer from insomnia and other sleep disorders, which can keep them from functioning normally during the day. Untreated sleep disorders can lead to conditions like obesity, diabetes, heart disease and stroke.

A 2010 analysis of a Statistics Canada database of 14,000 Canadians over 12 years old also concluded that sleeping pills were linked to a similar increase in risk of death, after the researchers controlled for other risk factors.