Growing use of antidepressants raises questions
The more popular antidepressants become, the more questions they raise. The drugs are one of the most widely prescribed types of medications in the United States, with more than 1 of every 8 Americans older than 18 having recently taken them, according to a survey from the Centers for Disease Control and Prevention. Yet, we know very little about how well antidepressants work over the long term, and especially how they affect overall quality of life, experts say.
Most clinical drug trials have followed people taking antidepressants for only eight to 12 weeks, so it’s unclear what happens when patients take them for longer than that, said Gemma Lewis, a research psychologist at University College London who studies the causes, treatment and prevention of depression and anxiety.
“We definitely need longer follow-ups of people who are using or are not using antidepressants, to see what the long-term outcomes are,” Lewis said.
A recent study published in the journal PLoS One aimed to close this knowledge gap by comparing, over the course of two years, the changes in quality of life reported by Americans with depression who took antidepressants with the changes reported by those with the same diagnosis who did not take the medications.
The study included people who took all types of antidepressants, including selective serotonin reuptake inhibitors such as Prozac, serotonin-norepinephrine reuptake inhibitors such as Effexor and older antidepressants such as clomipramine and phenelzine. Researchers assessed both mental and physical quality of life with a survey that asked questions about subjects’ physical health, energy levels, mood, pain and ability to perform daily activities, among other things.
The paper found no significant differences in the changes in quality of life reported by the two groups, which suggests that antidepressant drugs may not improve long-term quality of life.
Both groups reported slight increases in the mental aspects of quality of life over time and slight drops in their physical quality of life. But the study is imperfect, researchers say, and it certainly doesn’t settle the debate over the effectiveness of these drugs.
One problem is that the study, which was based on data from more than 17 million Americans who took part in the United States’ Medical Expenditures Panel Survey, compared people who may have been experiencing different levels of depression.
It’s likely that individuals who are prescribed antidepressants are more depressed than those who aren’t prescribed drugs, said Dr. F. Perry Wilson, a clinical public health researcher at the Yale School of Medicine, who was not involved in the study. So, it’s hard to make conclusions based on the findings, because “people with more severe depression might be less likely to improve their mental qualityof-life scores over time,” he said, for reasons that have nothing to do with the antidepressants they take.
Another issue is that the people who were taking antidepressants may have been taking them for a while — so, some qualityof-life improvements may have occurred before the study began following them, Lewis said. This kind of study “works best when you can measure quality of life before they go on the antidepressant,” she said, and when researchers can watch how the subjects’ lives change both immediately after starting the drug and later on.
Pills are often easier
Omar Almohammed, a pharmacologist at King Saud University in Saudi Arabia and co-author of the study, countered that it was still reasonable, however, to expect continued increases in quality of life even long after an antidepressant was started.
“If we don’t expect improvement from the continuous use of these medications, then the correct decision might be to stop the continuous use of these medications,” he said, or to add another kind of treatment, such as cognitive behavioral therapy, which aims to change people’s thought patterns.
Yet, pills are often easier and cheaper: It can be hard for people to access therapy because there aren’t enough providers, and mental health treatments often aren’t fully covered by insurance.
Clinical trials suggest that although antidepressants offer benefits over the first few months, the benefits are modest and are much less pronounced among people with mild depression compared with those with severe depression. Experts are divided over whether these small benefits make a noticeable difference to people’s moods or overall functioning.
Some doctors, for instance, have argued that the improvements people experience while taking antidepressants are not much larger than what they might experience taking sugar pills.
“They have marginal effects in the short term compared to placebo,” said Mark Horowitz, a research psychiatrist at University College London. That’s not to say that many people don’t feel better taking the drugs — it’s just that much of their improvement could stem from the placebo effect, rather than the medication itself.
Other researchers, including Lewis, argue that the benefits from antidepressants are significant enough to make a positive difference in people’s lives, at least for a few months. “There’s strong evidence that antidepressants can be effective for people experiencing a wide range of depressive symptoms,” she said. But, she added, the drugs “do not work for everybody.”
Longtime use
According to a New York Times analysis, 15.5 million Americans have been taking antidepressants for at least five years. Horowitz argued that the drugs would probably have increasingly smaller benefits the longer people took them, in part because patients could build up a tolerance to the medications.
Research suggests that people can also experience unpleasant withdrawal symptoms when they stop taking antidepressants, sometimes for weeks or months, and that the drugs can pose other risks, perhaps increasing the likelihood of strokes, heart attacks, falls and even death.
And like any medication, antidepressants can cause side effects.
If you are on antidepressants, Horowitz suggested checking with your doctor to see if you should continue taking them and, if so, to ensure you are still taking an appropriate dosage. The American Psychiatric Association recommends that patients who have experienced just one episode of depression take antidepressants for four to nine months. But people “should do so slowly,” Horowitz said, and ideally under the supervision of a doctor.
Many people can get life-changing benefits from these drugs and may benefit from taking them over the long term. But we all deserve to know more about how well they work and the risks they may pose when taken for years and even decades.
It’s clear that we need more careful research on how best to help the more than 16 million Americans who currently suffer from depression — and whose symptoms may have worsened during the pandemic.