The number of Americans seeking treatment of depression more than tripled - from 1.7 million to 6.3 million - between 1987 and 1997, researchers said Tuesday.
During the same period, the use of drugs to treat depression skyrocketed while the number of patients seeking psychotherapy declined.
The researchers attributed the sharp increases to the emergence of aggressively marketed new drugs like Prozac, the rise in managed care and an easing of the stigma attached to the disease.
The study found that the share of patients who used antidepressant medication climbed from 37 percent to nearly 75 percent. At the same time, the proportion who received psychotherapy declined from 71 percent to 60 percent.
While an increase in treatment for depression was not surprising, "the size of the increase was larger than I think most people in the field expected," said Dr. Mark Olfson, a psychiatrist at Columbia University and the New York State Psychiatric Institute who led the study. Studies since 1997 suggest the trend continues, he said.
The study was an analysis of two national surveys. The findings appear in Wednesday's Journal of the American Medical Association.
The publicizing of newer antidepressants that have fewer side effects - such as Prozac, which was introduced in late 1987 - has helped make patients more willing to seek treatment, the researchers said. This publicity has included pharmaceutical industry efforts to market the drugs directly to consumers and public-awareness campaigns about depression.
The rise in managed care also has contributed to the increase in use of medication, which may be less costly and time-consuming than psychotherapy, the researchers said.
Managed care also has placed more emphasis on primary-care physicians, who may be more likely to prescribe medication than to refer patients to specialists for psychotherapy, said Ronald Kessler, a professor of health care policy at Harvard University who was not involved in the study.
Kessler said evidence shows that combining medication with psychotherapy is the most effective treatment for depression. While many of the patients studied received both, some clearly did not, and Kessler said the findings do not indicate whether patients received adequate treatment.
The analysis is based on data from 34,459 people who participated in a 1987 medical expenditures survey by the U.S. Department of Health and Human Services. The researchers compared those findings with data from 32,636 participants in a similar 1997 survey by the Agency for Healthcare Research and Quality.
While the study shows "that the acceptance of a medical intervention for depression is clearly increasing, it still is significantly below what the potential need for care is," said Dr. Darrel Regier, research director for the American Psychiatric Association.
Other surveys have suggested that about 5 percent of the U.S. population - roughly 14 million people - could benefit from treatent for depression, but the study suggests that only about half that number are actually receiving care, Regier said.
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