Unclogging and propping open the large artery that supplies blood to the head can ease symptoms of depression in elderly people. That finding adds fuel to the debate over the hypothesis that impaired blood flow to the brain can cause depression.
Wolfgang Mlekusch of Vienna General Hospital in Austria and his colleagues identified 143 patients, average age 70, who were scheduled to undergo a procedure to open a blocked portion of the carotid artery. All patients had at least an 80 percent blockage in one of the branches of this artery, which carries freshly oxygenated blood from the heart.
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In the medical procedure, performed under local anesthesia, a doctor inserted a balloon-tipped catheter into an artery near the patient’s groin or in an arm and threaded it up to the neck. Then, the doctor inflated the balloon to push aside the blockage and installed a mesh cylinder called a stent, which propped open the carotid artery.
Before the operation, the patients filled out a standard questionnaire that measures signs of depression. The researchers calculated a score that gauged each patient’s depressive signs. At that time, the scores of 34 percent of the patients indicated significant depressive symptoms. The patients filled out the same questionnaire 4 weeks after the operation. Only 10 percent showed significant depressive symptoms then.
When the team compared pre- and postoperative scores, the average score fell by more than half. The researchers retested one-fourth of the patients 3 months later and found that the scores remained low, the team reports in the August Radiology.
For comparison, doctors gave the depression questionnaire to 102 people, average age 66, who were scheduled to have vascular surgery on their legs. The scores of 17 percent of these patients indicated depressive symptoms shortly before their operations. That percentage remained about the same 4 weeks after surgery.
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The findings lend support to the vascular-depression hypothesis, says psychiatrist David C. Steffens of Duke University Medical Center in Durham, N.C. If poor blood flow indeed does disrupt brain circuits that maintain normal moods, restoring the flow in those areas may rekindle “the normal drive and motivation to do things,” he says.
Stanton P. Newman, a psychologist at University College London, suggests that the before-and-after depression scores could have another explanation. Rather than prove that a carotid stent alleviates depression, he says, the study “more likely reflects the patients’ anxiety and depression as measured just before a high-risk operation”—and their sense of relief afterward. The patients who underwent leg surgery wouldn’t have felt as much anxiety, he contends.