Understanding the Side Effects of Antidepressants: Weight Change Among Common Treatments

Antidepressants are widely prescribed medications used to treat a variety of conditions including depression, anxiety, and chronic pain. With their prevalent use, concerns about side effects such as weight gain are common among patients and healthcare providers alike. A recent study, conducted by Joshua Petimar, ScD, and colleagues, sought to shed light on how different first-line antidepressant treatments impact weight change over time.

In a study published in the Annals of Internal Medicine, researchers used electronic health record (EHR) data spanning 2010 to 2019 from eight U.S. health systems, involving 183,118 patients. The observational cohort study, spanning 24 months, estimated the population-level effects of various antidepressants relative to sertraline (a commonly prescribed antidepressant) on mean weight change after six months of treatment initiation.

The antidepressants analyzed included sertraline, citalopram, escitalopram, fluoxetine, paroxetine, bupropion, duloxetine, and venlafaxine. The study's secondary focus was on the probability of patients gaining at least 5% of their baseline weight after six months.

The results revealed small yet significant differences in mean weight change across the eight antidepressant medications. Six months after starting the treatment, weight gain was higher for those on escitalopram, paroxetine, duloxetine, and venlafaxine compared to sertraline. On the flip side, bupropion consistently showed the least weight gain. Interestingly, escitalopram, paroxetine, and duloxetine were linked to a 10% to 15% increased risk of gaining significant weight, whereas bupropion was associated with a 15% reduced risk.

These findings were consistent even when accounting for differences in medication adherence. However, the study noted a low adherence to medications, ranging from 28% for duloxetine to 41% for bupropion at the six-month mark.

The study has important implications for both patients and clinicians. It suggests that when initiating antidepressant treatment, the potential for weight gain should be considered, especially for patients where weight or metabolic health are of concern. Bupropion, in particular, showed the least potential for weight gain and might be a suitable option for those at risk of obesity-related complications.

It's worth noting the limitations of the study, including a lack of concrete data on whether medications were dispensed or taken as prescribed, and the low overall medication adherence over the follow-up period.

This research was primarily funded by the National Institutes of Health. For those seeking further information, the full article can be accessed at Annals.org, with the study published on July 2, 2024, documented as doi:10.7326/M23-2742.

For additional informative articles and health tools, visit Buoy Health.

Download the full study from the Annals of Internal Medicine.