Metabolic syndrome, which is a cluster of medical issues that includes high blood pressure, a large waist and low HDL (good) cholesterol levels, may bring on mental decline in the elderly, according to a new study.

People with metabolic syndrome at the start of the study were 20 percent more likely to experience a decline in their working ("short-term") memory, and 13 percent more likely to experience a decline in their visual working memory than those without the syndrome, the results showed.

The researchers followed more than 7,000 men and women over age 65 in France for four years, and measured the participants' memory abilities with a battery of tests that included tests of verbal fluency, and overall cognitive function.

"This is a well-done, prospective study," said Dr. Kristine Yaffe, chief of geriatric psychiatry at the San Francisco VA Medical Center, who has done a number of studies on the topic but was not involved in this one. "While not entirely novel, it enforces an association with metabolic syndrome and cognitive decline over four years."

A number of studies over the past decade have revealed an association between metabolic syndrome and cognitive decline, but by following people over time, this study, the largest but not the first to do so, suggests a cause-and-effect relationship.

"Patients with [metabolic syndrome] may be well served to be screened periodically for cognitive impairment ," Yaffe said.

While the research may appear discouraging for older people already having a number of health problems , the researchers said the results may actually be encouraging for those who worry about and want to prevent a mental drop-off.

"As metabolic syndrome and its components are potentially modifiable, it would be possible to have...treatment for acting on cognitive decline and so preventing dementia," study researcher Dr. Christelle Raffaitin of the French National Institute of Health Research, told MyHealthNewsDaily.

While the researchers did not show that treating metabolic syndrome could prevent the mental decline seen in the study, others in the field are optimistic that would be the case.

"All of these are conditions that, through medication or through lifestyle changes, can be reversed or treated," said Molly Wagster, of the National Institute on Aging Division of Neuroscience. "There may be ways to prevent cognitive decline and progression to dementia , if components of metabolic syndrome are addressed."

It remains unclear what the connection might be between metabolic syndrome and the declines in cognitive abilities, the researchers said. One hypothesis is that the link may stem from the various components of metabolic syndrome that cause inflammation. This could affect the brain, in addition to other parts of the body. Raffaitin said it could be that only certain components of metabolic syndrome are causing the various types of cognitive decline.

But the role that each of the health issues that make up metabolic syndrome may be playing remains unclear.

"Different types of cognitive function may be affected, depending on what components of metabolic syndrome the individual has," said Wagster, pointing to the fact that visual working memory did not appear to be as impacted by metabolic syndrome as other working memory abilities.

"From these authors' findings, not every cognitive function is equally vulnerable," she said.

Pass it on: The bad news: high blood pressure and low levels of good cholesterol may contribute to memory loss in old age. The good news: these possible causes are treatable.

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