The researchers also found that individual patients were prescribed medications in greater combination to treat their mental illnesses than in previous years. The study is published in the January 2010 edition of the journal Archives of General Psychiatry.
“Our analysis shows that there has been a recent and significant increase in the number of medications prescribed by psychiatrists in the U.S.,” said Ramin Mojtabai, MD, PhD, MPH, lead author of the study and associate professor in the Bloomberg School’s Department of Mental Health. “While some medication combinations are supported by clinical trials, many are of unproven efficacy. These trends put patients at increased risk for potentially harmful drug interactions while the gains from better outcomes are uncertain.”
For the study, the researchers reviewed data from the National Ambulatory Medical Care Surveys. The cross-sectional study was a nationally representative sample of over 13,000 office-based psychiatry visits from 1996 to 2006. In addition to finding a general increase in number of medications prescribed, the study determined that number of office visits with two or more medications prescribed increased from 42.6 percent from 1996 to 1997 to 59.8 percent for 2005 to 2006. Visits in which patients received three or more medication prescription increased from 16.9 percent to 33.2 percent over the same period. The median number of medications prescribed per patient also increased from one to two over the survey period.
“A wide and ever-growing gap exists between the simple medication regimens that dominate clinical research trials and the complex regimens that increasingly characterize community psychiatric practice,” said Mark Olfson, MD, MPH, co-author of the study and professor of clinical psychiatry at Columbia University Medical Center.
Public Affairs media contact: Tim Parsons at 410-955-7619