Diet Drug Rimonabant Tied to Depression, Anxiety

Diet Drug Rimonabant Tied to Depression, Anxiety
THURSDAY, Nov. 15 (HealthDay News) -- People who take the weight-lossdrug rimonabant may face heightened risks for severe depression andanxiety, Danish researchers report.
The finding follows a recommendation by a U.S. Food and DrugAdministration panel in June that the agency not approve the diet drugbecause of continuing concerns about increased risks for suicidal thoughtsamong some users. Previously, the FDA rejected the drug as an aid to helppeople quit smoking.
"Up to this point in time, there has been controversy over the ratesand severity of psychiatric adverse effects with rimonabant," noted Dr.Philip Mitchell, head of the School of Psychiatry at the University of NewSouth Wales in Sydney, Australia, and co-author of an editorial thataccompanies the study.
This is the first review to examine rates of severe psychiatricsymptoms with rimonabant (Acomplia), symptoms severe enough that patientsdiscontinue treatment, Mitchell said.
The report is published in the Nov. 17 edition of TheLancet.
In the meta-analysis, Dr. Arne Astrup, from the department of humannutrition at the University of Copenhagen, collected data on more than4,100 patients enrolled in four clinical trials. Those trials comparedtaking rimonabant (20 milligrams a day) against a placebo.
The researchers found that people taking rimonabant did lose weight --about 15 pounds in a year -- compared to those receiving a placebo.
However, those taking rimonabant were also 40 percent more likely tohave an adverse reaction than people not taking it. In fact, those takingrimonabant were 2.5 times more likely to stop taking the drug because ofdepression and three times more likely to stop the drug because ofanxiety, compared to people on placebo.
"Our findings suggest that 20 milligrams per day of rimonabantincreases the risk of psychiatric events -- i.e., depressed mood disordersand anxiety -- despite depressed mood being an exclusion criterion inthese trials," Astrup's team said. "Taken together with the recent U.S.Food and Drug Administration finding of increased risk of suicide duringtreatment with rimonabant, we recommend increased alertness by physiciansto these potentially severe psychiatric adverse reactions."
Mitchell noted that depression is common in overweight and obesepeople, and is something that doctors need to take into account whenprescribing weight-loss drugs.
"This increased risk of depression and anxiety is a major safety issuein the treatment of obesity, as obese patients already have an increasedrisk of depression even prior to treatment," Mitchell said.
As far as rimonabant is concerned, Mitchell believes doctors shouldconsider alternate weight-loss drugs for people who are depressed. "If oneis using rimonabant, patients should be monitored carefully for theemergence of depressive symptoms and/or suicidal thoughts," he added.
In June, rimonabant's maker, French pharmaceutical giantSanofi-Aventis, said in a statement that despite the FDA's decision, thecompany "is confident in the positive benefit-risk ratio of rimonabant 20milligrams when used in the appropriate population."
Another expert said more data on the safety of rimonabant isneeded.
"Rimonabant is potentially beneficial in some patients, but we reallyneed long-term data demonstrating reductions in major obesity-relatedcomorbidities such as heart attack, stroke and sleep apnea and/ormortality, to be completely certain," said Dr. Raj Padwal, an assistantprofessor of general internal medicine at the University of Alberta inEdmonton, Canada.
The drug needs to be avoided in anyone who has a mood disorder, Padwaladded. "Since many patients with weight issues have depression, this meansthat the drug cannot be used in a large number of people. In the remainingindividuals in whom the drug is used, the patient and physician must becognizant of the risk of a mood disorder and monitor accordingly," hesaid.
In a related study in the Nov. 16 issue of the British MedicalJournal, Padwal's team found that long-term users of weight-loss drugssuch as orlistat (Xenical), sibutramine (Meridia) and rimonabantexperienced only modest weight loss -- less than 11 pounds, which was lessthan 5 percent of their total body weight.
Padwal's team also noted that the U.S. National Institute for ClinicalExcellence recommends stopping the use of weight-loss drugs if 5 percentof total body weight is not lost after three months.
Commenting on Padwal's study, Dr. Gareth Williams, dean of the Facultyof Medicine & Dentistry at the University of Bristol in the U.K.,wrote in an accompanying editorial: "Selling anti-obesity drugs over thecounter will perpetuate the myth that obesity can be fixed simply bypopping a pill and could further undermine the efforts to promote healthyliving, which is the only long-term escape from obesity."