Are newer antidepressants riskier for older people?

By Sophie Ramsey

BMJ Group News

What do we know already?

Depression is common among older people and many are treated with antidepressants. The most widely used are selective serotonin reuptake inhibitors (SSRIs), which include fluoxetine (brand name Prozac) and citalopram (Cipramil).

SSRIs are a newer class of antidepressant. Doctors often prescribe them because they are less likely to cause side effects, such as a dry mouth, than older drugs called tricyclic antidepressants (TCAs). TCAs include amitriptyline (Elavil) and dosulepin (Prothiaden).

There has been a lot of focus on the risks of SSRIs for young people under the age of 24. But researchers have done less work on their risks for older people, who may have other health conditions or be using other medicines.

In the new study, UK researchers compared the risk of potentially life-threatening problems in more than 60,000 people aged 65 and older who’d been diagnosed with depression. Using health records, they followed the patients for an average of five years. During this time, nearly 9 in 10 took one or more antidepressants from the following groups: SSRIs, TCAs, and other antidepressants, such as mirtazapine (Zispin) and venlafaxine.

What does the new study say?

People who took SSRIs or other antidepressants were more likely to have died during the study or had serious problems, such as strokes, compared with those who took TCAs.

Over the course of one year, 7 percent of people not taking any antidepressants died, compared with 8.1 percent of those taking TCAs, 10.6 percent of those taking SSRIs, and 11.4 percent of those taking other antidepressants. The risk of having a stroke for these groups was 2.2 percent, 2.3 percent, 2.6 percent, and 3.0 percent, respectively.

People taking SSRIs also had a higher risk of falls, broken bones, seizures, and raised salt levels (hyponatraemia), compared with those taking TCAs. People taking other antidepressants also had a higher risk of broken bones and seizures, as well as a raised risk of attempted suicide and self-harm.

For all the antidepressants, the risk of serious problems was highest within 28 days of starting or stopping treatment.

How reliable is the research?

This was a large study that drew information from a reliable database. The researchers also took into account many factors that could have influenced people’s risk of having serious health problems or dying during the study, such as their age, the severity of their depression, whether they had heart disease or other conditions, and whether they took other medicines.

However, it’s impossible to rule out all the factors that might have affected people’s chances of these problems. So, we can’t be certain that antidepressants are what raised their risk.

The researchers also point out that people taking TCAs were more likely to be prescribed low doses than those taking SSRIs. This might partially explain the raised risk of serious harms with SSRIs.

What does this mean for me?

If you are older and being prescribed an antidepressant, this study suggests that a TCA might be a safer choice than other antidepressants, including SSRIs. However, other research has shown that people are more likely to stop taking TCAs because of side effects, such as a dry mouth, constipation, and dizziness. These are all factors to consider with your doctor when weighing up the best treatment for you.

These findings also suggest that you and your doctor should be particularly alert to possible problems within a month of starting or discontinuing any antidepressant.