“Healthy” with Heart Disease: Pre-Diabetes and Pre-HypertensionFriday, June 15, 2012 - 20:30
How can you tell if your heart is healthy? For years, physicians and patients have relied on tools like the Framingham risk score, which compile information like blood pressure readings, blood cholesterol levels, age, gender, family history, and weight to calculate a person’s statistical risk of heart attack or stroke. But three studies released this week suggest that “apparently healthy people” who score in the low-risk category may be at greater risk of cardiovascular disease, including heart attack and stroke, than those tools show. The studies involved relatively healthy people — that is, people who did not have any symptoms of disease and who did not meet the criteria for a diagnosis of high blood pressure or diabetes. However, people in the studies did meet the criteria for prehypertension (blood pressure above120/80 mm Hg) and/or prediabetes (blood sugar of more than 100 mg/dL). Collectively, the results suggest that the “pre” categories may be more important indicators of heart disease than previously thought.
For the first study, Apparently Healthy U.S. Adults with Coexisting Prehypertension and Prediabetes Prone for Early Cardiovascular Events, researchers examined data from the U.S. National Health and Nutrition Examination Survey (NHANES). The results were dramatic: One in three apparently healthy adults had prehypertension, one in four had prediabetes, and one in ten had both. These “apparently healthy adults,” the researcher found, were ticking time-bombs for heart attack and stroke:
Adults who had both prehypertension and prediabetes were also overweight, had a larger waist circumference (abdominal obesity), higher ‘whole body’ inflammation and insulin (a hormone that reduces blood glucose). These subjects also had higher pulse pressure (the difference between the systolic and diastolic blood pressure), higher total cholesterol, triglycerides, higher ‘bad cholesterol’ along with lower ‘good cholesterol.’ These total, bad and good cholesterol levels made their “risk ratios” above desirable levels. All of these measures individually, and collectively, indicate an early high risk for heart attack or stroke.
The second study, Prediabetes Associated with Functional and Structural Cardiovascular Abnormalities, focused on changes in the blood vessels and hearts of people with prediabetes who didn’t have any other signs of heart disease and didn’t score in the “danger” zone on a commonly used risk assessment tool for heart disease, the Framingham risk score. Researchers compared 369 people who had prediabetes but no symptoms of heart disease with 1,277 people who had normal blood glucose levels. These results? People with prediabetes had early signs of cardiovascular disease, even though they showed no symptoms and would have been classified as having low- or low-intermediate-risk of heart attack or stroke.
A third study with an even fancier name — Early inflammatory and metabolic changes in association with AGTR1 polymorphisms in prehypertensive subjects — evaluated people with otherwise-healthy people with prehypertension for increased markers of inflammation and glucose metabolism, which are known to be elevated in people with heart disease. Again, people who fell in the “pre” category had showed signs that they were well along the road to heart disease. “We found that prehypertensive subjects were older with greater BMI than those with normal blood pressure, and after adjusting for multiple confounders, continued to display greater plasma glucose, insulin, leptin and interleukin-6,” said lead researcher Maple M. Fung, M.D., assistant professor of medicine, University of California, San Diego. “We conclude that prehypertensive subjects already exhibit early pathophysiologic changes that place them at risk of future cardiovascular disease with metabolic and inflammatory consequences….”
These are important findings. Both health-care providers and patients need to sit up and take notice. Prehypertension and prediabetes are not benign, easily reversible conditions but indicators that interventions are urgently needed. Interventions including education, lifestyle changes, support groups, and other non-drug ; in some cases, more aggressive treatment may be indicates. These studies also raise fundamental questions about how we define health. Each group of researchers emphasized that participants in their studies, despite meeting criteria for pre-diabetes or pre-hypertension, were “otherwise healthy” and did not show signs of disease. But that ’s a negative way to define health, as only the absence of disease. Isn’t health more than that?