According to a February 27, 2012, article in MedPage Today by Charles Bankhead, a study performed by research scientists of the Scripps Clinic in LaJolla, California, estimates, “Hypnotics [sleeping aids] may have been associated with 320,000 to 507,000 excess deaths in the U.S. alone.”
Compared with non-users, the risk of death associated with people who used sleeping aids—even if a prescription were for a small number of pills–was three to five times higher than those who did not use sleeping pills. While the study’s lead scientist, Daniel F. Kripke, MD, and co-authors wrote they couldn’t be certain what portion of the mortality associated with hypnotics might have been attributable to sleep aids, the consistency of their estimates against prevailing disease and health conditions points to the fact that the mortality due to hypnotics was “substantial.” One particular conclusion derived from the study stands out: “Patients who used hypnotics most often also had an increased risk of cancer, with an overall cancer increase of 35% among those prescribed high doses.”
Over the past thirty years, there have been at least 24 studies which in some way examined a link between mortality and sleep aids. One 30-year old study performed by the American Cancer Society examined smoking and sleep aids, and its results were discounted because the study was “not primarily designed to examine these drugs,” but was focused more on the effects of smoking.
The authors of the Scripps study also noted that “"A consensus is developing that cognitive behavioral therapy [for] chronic insomnia may be more successful than hypnotics,” and from the results of this study, perhaps less risky as well.
 “Sleeping Pill Death Toll May Top 500,000”, Bankhead, Charles, MedPage Today, 2/27/2012, http://www.medpagetoday.com/PrimaryCare/SleepDisorders/31391?utm_content=&utm_medium=email&utm_campaign=DailyHeadlines&utm_source=WCemail@example.com&mu_id=