23 December 2005

The metabolic syndrome is associated with the development of silent brain infarction (SBI) in otherwise healthy individuals, putting them at risk of overt stroke and dementia, South Korean scientists have found.

SBI - a cerebral infarction that is evident on brain imaging such as magnetic resonance imaging (MRI), but does not have an associated clinical syndrome - can predict clinically overt stroke or dementia, while metabolic syndrome is linked to an increased risk of cardiovascular disease or stroke.

To look at links between the two conditions, Byung-Woo Yoon, from Seoul National University Hospital , and colleagues performed brain MRI on 1588 neurologically healthy individuals aged from 20 to 86 years. The diagnosis of metabolic syndrome was based on the National Cholesterol Education Program Adult Treatment Panel III criteria, with both the overall syndrome and its components examined for associations.

In all, 5.5% of the participants were found to have at least one SBI on MRI. Age was significantly related to SBI prevalence, with an odds ratio of 1.06, while a history of coronary artery disease conferred an odds ratio of 2.83.

The metabolic syndrome was found to be significantly associated with SBI, with an odds ratio of 2.18. Elevated blood pressure conferred a 3.75-fold increased risk of SBI, and impaired fasting glucose a 1.74-fold raised risk.

The team concludes in the journal Stroke : "The present study demonstrates that metabolic syndrome is associated with SBI independently of traditional cardiovascular risk factors.

"These findings reaffirm the clinical importance of metabolic syndrome as a significant risk factor of SBI and the need to develop strategies for controlling this syndrome and its component conditions."