For years, doctors have been aware that antidepressants can have side effects that impact cardiovascular and metabolic health. However, a groundbreaking analysis conducted by a team of researchers in the U.K. has, for the first time, compiled data from over 150 clinical trials to compare the physical side effects associated with various antidepressants. Published in this week's issue of The Lancet, the study provides a comprehensive overview of how each medication affects vital health metrics, including weight, blood pressure, heart rate, cholesterol, and more.
The study, led by Dr. Toby Pillinger, a psychiatrist at King's College London, resembles a sports league table, ranking 30 different antidepressants based on their side effect profiles. Dr. Pillinger emphasizes the unprecedented scale of this research, stating that it is the first time specific numerical values have been assigned to potential weight gain or cholesterol increases associated with these medications.
The findings are drawn from existing data, primarily from 8-week drug studies that collectively represent more than 58,000 patients. Notably, the most commonly prescribed antidepressants in the U.S., known as Selective Serotonin Reuptake Inhibitors (SSRIs) such as Zoloft and Prozac, generally exhibited fewer physical side effects compared to other medications. In contrast, older antidepressants displayed more significant impacts on health metrics.
For example, individuals taking nortriptyline, a tricyclic antidepressant, may experience an average heart rate increase of 20 beats per minute compared to those on the SSRI fluvoxamine. Furthermore, the expected weight change associated with various medications could range from an average gain or loss of four pounds. Dr. Pillinger clarifies that the aim of this study is not to label certain antidepressants as superior or inferior but to assist in tailoring treatment to individual patient needs.
To facilitate informed decision-making, Dr. Pillinger and his team have developed a free digital tool that is currently being utilized by clinicians worldwide. This resource helps create a personalized menu of medication options based on each patient's health profile and their desired side effects.
Dr. Nina Kraguljac, a professor at the Ohio State University who did not participate in the research, praised the study for its thoroughness and largely reassuring findings. She noted that the side effects were not as severe as she had anticipated, but she cautioned that side effects should not solely dictate clinical decisions, as the results represent averages and do not apply universally to all patients.
While the study presents valuable insights, it is essential to recognize its limitations. Most of the data was derived from 8-week randomized controlled trials, which are commonly conducted. Additionally, some significant side effects that often lead patients to discontinue antidepressant use were not evaluated. Dr. David Hellerstein, a psychiatry professor at Columbia University, highlighted the absence of common complaints such as sexual dysfunction, gastrointestinal issues, and emotional blunting, which were not included in the analysis.
Nonetheless, Dr. Hellerstein believes that the study will serve as a useful reference for both patients and prescribers. He points out that most antidepressants, especially newer options like SSRIs and SNRIs (Serotonin-Norepinephrine Reuptake Inhibitors), appear to be safe concerning various physical health parameters.
It is important to note that side effects are not always negative. Dr. Hellerstein shared an example of a patient who had lost significant weight due to depression; in this case, an antidepressant that resulted in weight gain could actually be beneficial. "I would say that is not a side effect. That is a benefit of treatment," he remarked.
This comprehensive study offers valuable insights into the physical side effects of antidepressants, paving the way for more personalized and informed treatment strategies for individuals battling depression.