Bupropion May Be Best for Overweight Patients With Depression
Abstract
While the mechanism of the weight-reducing effect of bupropion has yet to be determined, researchers suspect that the dopaminergic and noradrenergic effects of the medication may play important roles in the regulation of appetite, satiety, craving, and feeding behavior.
Obesity and its relationship to antipsychotic medication is a concern now well known to physicians treating patients with schizophrenia. But what about the relationship that exists between depression, antidepressant treatment, and weight gain?
The association between antidepressant therapy and long-term weight gain may not be as pronounced as in the case of antipsychotics, but any weight gain attributed to antidepressants should be of concern—particularly when prescribing to patients who are overweight, David Arterburn, M.D., an internist and an expert in obesity with the Group Health Research Institute (GHRI) in Seattle told Psychiatric News.
“As many as two-thirds of Americans are overweight, and a significant number of those are individuals with depression,” Arterburn said during an interview. “We don’t need to add even a few more additional pounds that will increase their risk for obesity-related diseases if we can help it. So if we are able to treat depression and at the same time promote even modest weight loss, it would be a win-win.”
Arterburn was the lead author of a study published online April 13 in the Journal of Clinical Medicine that suggests bupropion may be the best first-line antidepressant for patients with weight issues.
Together with GHRI psychiatrist Gregory Simon, M.D., and colleagues, Arterburn examined the relationship between antidepressant medication and weight change over a two-year period among adult patients with a new antidepressant treatment episode between January 2006 and October 2009 in the Group Health Cooperative—a large health system in Washington state.
Psychiatrist Gregory Simon, M.D., said assessing the effect of antidepressants on weight gain can be difficult in a clinical setting since weight gain is gradual and most people gain some weight as they age.
Medication use, diagnoses, height, and weight were collected from electronic databases. Antidepressants included in the analysis were fluoxetine, citalopram, bupropion, paroxetine, sertraline, trazodone, mirtazapine, venlafaxine, and duloxetine. (During the study years the second-generation antidepressant medications escitalopram, fluvoxamine, and nefazodone were not on the Group Health formulary and so were not included.)
The reference medication against which other antidepressants were measured for effect on weight was fluoxetine, the most commonly prescribed antidepressant at Group Health.
Aterburn, Simon, and colleagues found that nonsmokers who initiated bupropion treatment on average lost 7.1 pounds compared with nonsmokers taking fluoxetine. Changes in weight associated with all other antidepressant medications were not significantly different than that of fluoxetine, except for in sertraline users, who gained an average of 5.9 pounds.
(The only antidepressant for which the weight gain was found to be as pronounced as that of antipsychotics was mirtazapine; those using the drug gained on average 11.6 pounds compared to fluoxetine users, but because of the small number of patients receiving that medication, the finding was not statistically significant.)
“[I]t is suspected that the dopaminergic and noradrenergic effects of bupropion play important roles in the regulation of appetite, satiety, craving, and feeding behavior,” the authors wrote.
The weight loss effect for bupropion was not seen in smokers, many of whom were likely being prescribed the drug specifically for smoking cessation. “People who are trying to quit smoking are commonly known to gain weight on average,” Arterburn explained. “So, the effect of quitting smoking on weight gain was big enough to reverse the protective effect of bupropion on weight.”
Simon told Psychiatric News that the relationship between depression and weight gain—and the possible compounding influence of antidepressants—is complex.
“We know from lots of previous research that people who are depressed are more likely to be obese,” he said. “Is that because depression increases the risk for weight gain, or because overweight people are more likely to be depressed? On top of that, if people are taking an antidepressant, how do you know if this is related to the medicine?
“In clinical practice it’s a challenge, because weight gain is a gradual thing, unlike other side effects. If you want to know if a particular medication causes nausea—that’s not hard to tell. But all people on average gain weight as they age, so if someone is taking medication and gradually gaining weight, it’s difficult to know the cause.”
Simon said the new study suggests that all antidepressants have some effect on weight and that only bupropion actually lowered weight at two years.
“Previous research has confirmed that treatment effects on depressive symptoms are roughly equal across all antidepressants, so clinicians largely make prescribing decisions on the basis of side effects and cost,” Simon added. “For patients for whom obesity is a serious problem, the findings from the study are an important piece of information to consider.”
Arterburn and Simon said future research at the GHRI will focus on genetic factors that may indicate which patients being prescribed antipsychotics or antidepressants are most likely to experience weight gain.
The study was funded by a grant from the National Institute of Mental Health. ■
