This news release describes results of a retrospective study by Group Health on the link between antidepressant drugs and weight change over a two-year period in adults with already-diagnosed depression. The results of the study suggest that compared to a “reference” drug, fluoxetine (best known as Prozac), an SSRI or selective serotonin reuptake inhibitor, only bupropion (marketed as Wellbutrin), an NDRI (norepinephrine-dopamine reuptake inhibitor) was associated with modest long-term weight loss and only in non-smokers. The news release doesn’t give us any details on costs or side effects associated with the drugs nor does it tell us how the data was measured or analyzed. It also doesn’t include several limitations of the research included in the published study.
[Editor’s note: Dr. Arterburn, the lead study investigator quoted in the news release, is a former reviewer and contributor to HealthNewsReview.org.]
Depression takes a significant toll on human health, well-being and productivity. It’s a challenging condition to treat, costs billions every year worldwide, and suicide is a too-frequent outcome.
Antidepressants are among the mostly commonly prescribed (and heavily marketed) drugs available, and a vast literature about their use suggests there is no particularly significant difference in their effectiveness. All carry some side effects as well. Because many SSRIs have long been linked to weight gain, for obese depressed patients, trying buproprion first might make good sense. Average monthly costs vary widely depending on the availability of generics and doses, and in most cases costs are comparable and covered by insurance, so “differentiators” such as weight issues are not insignificant.
A quote from one of the study’s co-authors mentions “costs” and “patient preferences” as sensible considerations in first choice of antidepressant therapy, but the release offers no information about the comparative costs of the drugs that were studied or even the estimated average annual cost of such therapy. The release would have been strengthened by such data.
The release states that “After two years, nonsmokers lost an average of 2.4 pounds on bupropion–compared with gaining an average of 4.6 pounds on fluoxetine (Prozac). So those who took bupropion ended up weighing 7 pounds less than did those on fluoxetine.”
With the exception of a mention that some people can’t take buproprion (seizure disorder patients, for example), and the weight gain issue, the release makes no mention of the considerable side effects that accompany antidepressant use, or the often frustrating search patients and physicians must undertake to find an antidepressant that is both effective and tolerable for individual patients. Fatigue, insomnia, increased anxiety, headache and nausea are all fairly common when starting an antidepressant.
The release does not make it clear that this is a retrospective study and not one set up to study the effect of antidepressants on weight gain or loss. The published study’s summary offered detailed information about the makeup of the study population and the strengths and weaknesses of the study’s data and analytic approach. Not much of that information was used in the release.
To be helpful to readers, the release should have noted at least some of these limitations that were pointed out in the study:
The release doesn’t engage in disease mongering. Nor does it give us any context about the prevalence of depression which might have been warranted here.
That’s pretty well covered, with lots of information about Group Health and the grantors.
In essence, the purpose of this study was to compare alternatives and report their effect on weight gain or loss. The news release notes that fluoxetine was chosen as the “reference” drug to compare with buproprion. The study suggests that in addition to fluoxetine, the researchers looked at data from patients assigned to a number of other drugs, too, but their data sets were incomplete.
The release makes clear that all of the antidepressants are available and approved.
The release claims that the study was the first to examine weight gain in people using antidepressants for more than a year, in this case up to two years.
The release doesn’t rely on unjustifiable language. We would underscore the study author’s comment that “bupropion is the best initial choice of antidepressant for the vast majority of Americans who have depression and are overweight or obese” by adding that each individual needs to be evaluated for their symptoms with a medical professional making a recommendation on the appropriate drug therapy.