A new study finds that Prozac can significantly improve recovery from stroke— the number one cause of adult disability and the third leading cause of death in the U.S. The randomized controlled trial found that while patients given placebo for three months starting 5-10 days after a stroke improved 24 points on a 100 point scale that measures functioning, those given the antidepressant improved by 34 points.
All patients were given standard physical therapy to aid recovery from weakness and paralysis caused by the stroke.
The study included 118 patients— all of whom started out below 55 on that scale after surviving a stroke linked to a blood clot in the brain. That form of stroke—known technically as an ischemic stroke— is the most common type in the U.S. The improvement is large enough that for some patients, it could make a difference in their ability to live independently. The research was published in the journal Lancet Neurology.
The co-author of an editorial that accompanied the study told WebMD:
“We’re not talking about a couple of points on the scale as happens in Alzheimer’s disease where the improvement in barely noticeable,” says Robinson, who co-authored an editorial on the study. “We’re talking about patients who are a whole category improved. We’re talking about clinically and significantly bigger improvement for the patient and their family.”
The study was funded by the French government and adds to a growing body of research linking SSRI antidepressants like Prozac to improvements following stroke. The benefits, say experts, go beyond the drugs’ effects on depression, which is also common after stroke.
The findings add to research suggesting that these antidepressants may affect the brain not simply by raising serotonin levels—the popular explanation for their action— but by allowing the brain to repair damaged connections and add new ones.
Almost all antidepressants, regardless of which neurotransmitters they initially affect, increase levels of substances that repair and stimulate the growth of brain cells a few weeks after they are started. Electroconvulsive therapy (ECT) also causes these kinds of changes. Probably not coincidentally, it typically takes a few weeks for such treatments to fully lift depression.
The results also support research that links depression, cardiovascular disease and inflammation: another effect of SSRI’s on the brain is to reduce inflammation. Increased inflammation has been connected to both depression and cardiovascular disease in prior research.
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