PROVIDENCE, R.I. [Brown University] — Advertising prescription drugs to consumers is forbidden in most of the world, but since U.S. guidelines were relaxed in 1997, such ads have become nearly ubiquitous in American media. In a newly published review, Brown University researchers examined what has been learned since then about the effect of all that advertising on psychiatric conditions. They found that the data are very limited, but what does exist suggests that ads succeed in driving prescribing with potentially mixed effects on patient care.

“On a basic level, the goal of our review was to begin addressing an important and rarely examined public health question,” said lead author Sara Becker, a research assistant professor at the Brown University School of Public Health and the Warren Alpert Medical School. “Is this enormous multibillion dollar industry of direct-to-consumer advertising of psychiatric medication affecting public health in a positive or negative way? There are many possible ways to answer this question — we began by taking a close look at patient and physician behavior in response to these ads.”

It’s a germane question in psychiatry because in recent years, medicines for mood disorders and other conditions have become some of the most advertised and biggest selling drugs.

The new paper appears online in the Journal of Clinical Psychiatry.

Reviewing the scant evidence

While doctors and others have been debating the perceived merits or dangers of direct-to-consumer advertising (DTCA) for years, Becker and co-author Miriam Midoun found few studies that have analyzed how such ads affect encounters between doctors and patients and even fewer that have zeroed in on psychiatry. In fact, they could find only four studies that met their criteria for analysis — studies that include advertised psychiatric medicines, tracked prescribing behavior based on patient requests for those drugs, and documented specific doctor-patent interaction at the point of care (rather than in general, or retrospectively).

One was a randomized controlled trial, conducted in 2005, in which actors posing as patients presented to doctors with different degrees of depression. The “standardized patients” would then either ask for a specific brand of drug they saw on television, ask in general for an antidepressant because they viewed a commercial, or not ask specifically for a medicine. That study found significantly higher rates of prescribing when patients asked for the drugs than when they didn’t. The other three studies all corroborated that trend, including a 2003 article in which the researchers compared prescribing rates in Canada, where DTCA is forbidden, to rates in the U.S.

Though the studies all suggest that most patient requests for medications will be granted, the three studies involving observations of real patients found that requests for medications are hardly a fixture of doctor-patient discussions. Requests for advertised drugs occurred less than 10 percent of the time in the studies, the authors found. The U.S.-Canada study, however, showed that U.S. patients asked for medications at more than double the rate of Canadian patients.

With advertising seemingly influencing some patients to ask for drugs and doctors often being willing to prescribe drugs when asked, one of the biggest questions is whether the right treatment is occurring for the right patients. The authors found only the randomized controlled trial had the strong methodological quality to address the issue.

Based on the data from the 2005 study, it appeared that when standardized patients with severe symptoms of depression asked for medication, they were more likely to get it. That could be good, Becker said, because people who objectively needed such care were getting it. But the standardized patients with less severe or transient depression (an “adjustment disorder”) were also more likely to get prescriptions if they asked for them. That could create a problem, because in these cases medication wasn’t medically necessary.

With the other studies also documenting increased drug requests and prescriptions for psychiatric medicines, Becker said, the limited evidence appears to support the possibility that DTCA has mixed effects on treatment quality. Its possible that DTCA may result in increased prescribing for patients who actually need it, but also overprescribing for patients who don’t.

Ultimately, the field needs more data than these few studies have provided, Becker said.

“In 2007, the editor of Annals of Family Medicine referred to direct-to-consumer advertising of prescription drugs as ‘a huge, uncontrolled public health experiment on American people,’” Becker said. “Our review supported this statement. Very few rigorous studies have been conducted on DTCA over the past 20 years. But our review also didn’t support a clear decision for or against DTCA — the limited data aren’t all bad or all good. It’s possible that DTCA might help some people and might lead to over-prescribing in others.

“The most important conclusion of our study is that more research is needed.”

The National Institute on Drug Abuse funded the study (grant: K23DA031743).