It’s not fortune telling, although the signs are clear: Early brain imaging helps identify, prevent and treat patents at increased risk for heart attack or stroke. In a meta-analysis study, early brain imaging scans revealed changes to brain structure and function, acting as warning signs of cardiovascular and cerebrovascular events to come.
The study was published in the October issue of the Journal of the American College of Cardiology: Cardiovascular Imaging.
Across 33 years of studies on brain imaging, Joseph I. Friedman, MD, from the Icahn School of Medicine at Mount Sinai in New York, and colleagues found 77 studies that followed asymptomatic patients with vascular disease risk factors. From the imaging modalities available through these studies, they found patients with high blood pressure, obesity, high cholesterol, diabetes, metabolic syndrome or smoking history and no history of heart attack, stroke, MI or transit ischemic attack had visible changes to the way their brains worked.
Hypertension caused whole brain volume reduction and brain cerebrospinal fluid space enlargement. These brain scans also revealed reduced blood flow, changes in normal patterns of synchronized brain activity and brain connectivity abnormalities.
MR imaging of patients with metabolic syndrome revealed increased burden of silent brain infarcts, presaging subclinical cerebrovascular disease. Moreover, patients with metabolic syndrome had reduced activation on regions associated with cognitive tasks. Connection abnormalities and changes to normal synchronized brain activity also correlated to reduced performance on cognitive tasks.
Obesity reduced total brain volume in patients and had effect on white matter coherence. Friedman et al also noted decreases to brain blood flow and negative effects to glucose metabolism in areas associated with cognitive performance.
High cholesterol reduced total brain volume, metabolism and decreased brain coherence. High triglyceride levels in particular decreased blood flow in the brain. Lipid-lowering medications, however, did not affect cerebrovascular, connectivity or density changes.
Changes were simple and increasingly effective if patients were caught early. For example, aerobic fitness led to greater brain coherence and improved function in obese patients. Timing hypertensive treatment properly -– treating blood pressure during midlife rather than waiting until late in life -– changed brain volume loss and blood flow outcomes. Waiting until late in life to treat or leaving a patient untreated instead presaged increased loss.
As these risk factors are modifiable, Friedman et al recommended early identification and intervention to prevent catastrophic events. Fellow author Valentin Fuster, MD, PhD, of the cardiology division at Mount Sinai, said in a press release that patient control of risk factors “needs to start today,” and that physicians and patients alike need to work together to modify these factors. “These high-risk patients, along with their doctors, hold the power to modify their daily vascular risk factors to help halt the future course of the manifestation of their potentially looming cardiovascular diseases.”