Can Short-Term Antidepressant Use Lead to a Better Long-Term Outcome? It's Complicated ...

Patient Expert

Last year, I posted a piece, Antidepressants Over the Medium and Long Term: Little to No Evidence. I based my narrative on four leading psychiatric treatment guidelines.

The key to legitimacy with any type of medical treatment guideline is evidence-based medicine. Every claim, every recommendation, has to be backed up by scientific data, ideally strong and unambiguous, and lots of it.

The guidelines cite no end of clinical trials to validate doctors prescribing antidepressants to boot their patients out of a depression. But what next? How long should a patient remain on his or her antidepressant?

Unfortunately, there is precious little data. Enough to suggest the value of staying on your antidepressant for a little while after your depression has lifted, but nothing to justify a long-term commitment.

Accordingly, in the absence of long-term studies, the guidelines wisely couch their recommendations in terms of weeks or months, not years.

Okay, let's try a new question ...

Say you take antidepressants for a short time and get well. How will this affect your outcome eight years later? Are you likely to be better off than those who never took an antidepressant?

Funny you should ask. The other day, my fellow blogger Natasha Tracy reported on a 2011 University of Alberta study that tackled this question head-on.

These type of studies are virtually impossible to conduct, thanks to a phenomenon called confounding variables, which the study authors thusly acknowledge. For instance:

People who take antidepressants are more likely to be more severely depressed than ones who don't. They may be poor prognosis patients. Therefore, the study biases against the antidepressant.

It also works the other way: People who take antidepressants may actually take better care of themselves than those who never took antidepressants. They may, in fact, be good prognosis patients.

The trick is to design a study that controls for these and a zillion other variables. The authors state that they used "propensity score techniques to account for non-random allocation for treatment and subsequent confounding by indication."

Clear as a bell, right? Okay, let's cut to the chase ...

The study tracked 486 depressed individuals, nearly a third who were on antidepressants in 1998/1999. After eight years, "depressed individuals who received antidepressant use in 1998/99 were less likely to be depressed in 2006/07 compared to those who did not use anti-depressants."

Keep in mind, this was not a study about long-term antidepressant use. Instead, the study suggests that short-term depression use can lead to a favorable long-term outcome - but there are some major catches.

In particular, the authors stress the importance of aiming for complete remission before going off your antidepressant. When all is said and done, this is the real lesson of the study.

Remission, not response ...

Back at my first American Psychiatric Association annual meeting in 2002, I heard Michael Thase of the University of Pittsburgh explain that "remission" involved the virtual elimination of all symptoms. This is what doctors and patients need to be aiming for.

"Response," on the other hand, involves a 50 percent or more reduction in symptoms. Response is the threshold for a successful drug company trial. In other words, response is what makes industry executives happy, not you.

Dr Thase emphasized that patients who achieved a response or only partial remission were more likely to suffer a relapse or recurrence. He cited study evidence in support, as do the authors of the current study.

At numerous other sessions over the years, I have heard Dr Thase and other experts hammer home this message.

The catch, though, is antidepressants seldom get the job done on their own. Fortunately, at that 2002 APA meeting, Dr Thase also reported the results of a study he was involved in. This study tested for the combined effects of antidepressant treatment and cognitive-behavioral therapy. Those on the combined regimen had double the remission rates of those on one or the other.

Take-home message

There is a lot we do not know about antidepressants. But what we do know suggests this:

If you are one of those who is responding well to your antidepressant, it makes sense to go all the way and aim for remission. This may involve a lot of extra effort - such as staying on your med for a few months or more, engaging in cognitive therapy, and getting serious about good lifestyle routines, plus whatever else works for you.

This is easier said than done, but it appears that the pay-off is manifold: Reduced likelihood of relapse or recurrence, and greater chance of living well years from now. Funny thing, the people in the study who weren't on antidepressants at the beginning of the study were more likely to be on antidepressants at the end. You really don't want that, do you?