Ads work on doctors, study shows

Primary-care doctors are easily persuaded to prescribe antidepressants – even unnecessarily – when a patient mentions having seen television advertisements for them, researchers reported Tuesday.

In an unusual experiment in which actresses posed as mildly depressed patients who did not need medication, doctors were five times more likely to write them prescriptions when an ad for a specific drug was mentioned.

Drug companies spend roughly $3 billion a year on direct-to-consumer advertising, fomenting sharp debate over how much sway the advertisements have over doctors. The study showed the effect is significant.

“When patients ask for a drug, they tend to get a drug regardless of whether it is appropriate for them,” said Joel Weissman, a health-policy expert at Harvard Medical School who was not involved in the research. “That is a fascinating finding.”

Surveys have shown that in up to 7 percent of doctor visits, a patient requests a prescription based on an ad – a rate that experts say can significantly boost sales.

In the study, published in the current issue of the Journal of the American Medical Association, the patients were actresses all playing the same part: a 45-year-old divorcee who had recently lost her job and was suffering from stress, fatigue and back pain. Those are symptoms of adjustment disorder, a mild, event-induced depression in which medications are thought to be of little value.

Each actress used these lines to request Paxil, a popular antidepressant: “I saw this ad on TV the other night. It was about Paxil. Some things about the ad really struck me. I was wondering if you thought Paxil might help me.”

Out of 49 such visits, 27 – or 55 percent – resulted in a prescription for an antidepressant, most often Paxil.

By comparison, patients who did not mention an ad were prescribed antidepressants just 10 percent of the time.

Critics of direct-to-consumer advertising say it leads to needless prescribing. Drug companies argue that the ads simply increase patient awareness, allowing more people to get the proper diagnoses – and drugs.

The study suggests that both sides are right.

While the ads led to unnecessary prescriptions of antidepressants for adjustment disorder, a separate experiment showed that the ads could improve treatment.

Actresses posed as a 48-year-old divorcee who had been feeling down for a month and suffered from poor sleep, appetite and a general loss of interest in her usual activities – the symptoms of major depressive disorder.

Appropriate treatment includes at least one of three options: a prescription for an antidepressant, a referral to a mental-health specialist, or a follow-up visit within two weeks.

Bringing up the Paxil ad with the doctor resulted in proper treatment 90 percent of the time, including an antidepressant prescription 53 percent of the time.

Patients who did not mention the ad got appropriate treatment 56 percent of the time. Only 31 percent got a prescription.

“There’s a whole lot of medicine that is practiced in the gray zone,” where social influences matter as much as clinical findings, said Dr. Richard Kravitz, a professor of medicine at the University of California, Davis, and lead author of the study.

Depression can be difficult to diagnose, and many people resist the possibility that an illness may be mental. An openness to trying an antidepressant appeared to be an important cue to the physicians, Kravitz said.

The doctors had agreed to participate in a study “assessing social influences on practice,” but were told only that they would receive two undercover visits from research subjects several months apart.

Kravitz said doctors might have been more cautious had the visits occurred after the Food and Drug Administration required that antidepressants carry “black box” labels warning that the drugs have been linked to suicidal thoughts.

Still, there are other well-known side effects, including sexual dysfunction.

Authors of the study said in interviews that the benefits of direct-to-consumer advertisements could be achieved with informational ads that do not plug a specific brand.

Each arm of their experiment included a third group: actresses who did not mention a specific antidepressant but told doctors: “I was watching this TV program the other night. It really got me thinking. I was wondering if you thought a medicine might help me.”

That statement led to the best care for both the patients complaining of symptoms of major depressive disorder and those complaining of symptoms of adjustment disorder.