# our shrinking brains?



## trbell (Nov 1, 2000)

Continuing Medication Could Prevent 'Shrinkage' of Key Brain Regionin Depressed PatientsBy <http://my.webmd.com/content/Biography/7/65292.htm>Sid Kirchheimer WebMD Medical News on Friday, August 01, 2003Aug 1, 2003 -- Optimism, motivation, and hope aren't the only thingsstunted by depression. So is the size of a specific region of thebrain.Researchers have long known that the hippocampus, a part of the braininvolved in learning and memory, is usually smaller in people with ahistory of depression than in those without the disease. But newresearch suggests that depressed patients who continue to takeantidepressant medication -- even when they're feeling better -- maybe more likely to minimize or possibly prevent this shrinkage.Using MRIs, scientists at Washington University School of Medicinemeasured the size of the hippocampus in 76 women -- half had repeatedbouts of major depression while the others had no history ofdepression. Not only did the researchers find that the depressedwomen had a smaller hippocampus, but its size was largely determinedby how long they continued their medication. The less time spent onmedication, the greater the shrinkage.The Longer the Medication, the More Protection"The take-home message is that not only do antidepressants helpprevent relapse of depression in patients with a history of recurrentdepression, but they also appear to protect against brain volume lossassociated with depression," researcher Yvette I. Sheline, MD, tellsWebMD."Our results suggest that if a woman takes antidepressants whenevershe is depressed, depression would have less effect on the volume ofher hippocampus. It is the untreated days that seem to affecthippocampal volumes."Only women were studied because statistically, they are twice asvulnerable to depression as men, and Sheline focused only on theirmedication usage -- and not other important treatments such aspsychotherapy.Her study -- published in the August issue of the American Journal ofPsychiatry -- is especially important because patients with majordepression are prone to relapses even after long-term antidepressanttreatment and others discontinue their medications once symptomssubside.Most experts recommend treatment with antidepressants for at leastsix months -- and usually longer -- to prevent relapse. But a studylast February in the American Journal of Managed Care indicates thatmany patients stop taking their medication within three months, andit's these patients who face a great likelihood of a relapse.Learning and Memory Brain RegionWhy this hippocampus shrinkage occurs in people with depression isnot clearly established, but there are two prevailing theories:Either stress hormones such as cortisol released during a depressiveepisode damage brain cells or the disease destroys connectionsbetween nerve cells.Although this part of the brain is not directly involved in mood,Sheline says it is closely tied to another part of the brain that is.The hippocampus is more closely associated with learning and memoryskills, and previous research suggests that depressed people tend toscore lower on certain memory tests, especially those tied to verbalabilities.Bruce S. McEwen, PhD, the researcher credited as being the first todiscover that the hippocampus has receptors for stress hormones thatcan damage it, says that Sheline's study is significant. He directs aneuroendocrinology laboratory at The Rockefeller University in NewYork, a leading biomedical research facility."She's certainly the leader in showing that the hippocampus shrinkswith prolonged depressive illness and now, this study suggests thatmaybe you can do something about it," he tells WebMD."In the first episode of depression, there doesn't seem to be asmaller hippocampus, so this shrinkage has to develop over time. Inour animal studies, we found that you can reverse these changes ifyou stop the stress up to a certain point."Antidepressant medications can do that by controlling the release ofstress hormones such as cortisol. "But there's also evidence thatthese medications increase cell proliferation in certain brainregions, and one of the attractive mechanisms is an enhancement of anew generation of new nerve cells, which are being replaced all thetime in this part of the hippocampus," McEwen says.Sheline is now trying to determine whether continued treatment withantidepressants can actually restore the hippocampus to "normal"size. In her current study, she did not investigate whether anyspecific medications were more effective than others; all seem toprotect the brain better than no treatment, she says.Bada


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