Metabolic Syndrome Puts Adolescents on the Road to Heart Disease By Paula Rasich Reviewed By Elizabeth Klodas, MD, FACC (CardioSmart) Metabolic syndrome---the collection of risk factors that includes abnormal blood cholesterol levels, high blood pressure, central obesity (weight gain around the middle) and elevated blood sugar levels---can be hazardous to your cardiovascular health. But a new study suggests that the combination of these disorders increases heart risk even in young individuals.

Marcello Chinali, MD, a visiting fellow at Weill Cornell Medical College in New York City, and colleagues examined data from the Strong Heart Study, an ongoing investigation of cardiovascular risk factors and disease in more than 4,000 American Indians that began in 1988. In the fourth phase of this study, researchers evaluated whether metabolic syndrome was associated with very early signs of heart disease in 446 adolescents, ages 14 to 19. Using a set of criteria developed for adolescents, 111 participants were diagnosed with metabolic syndrome.

Left ventricular hypertrophy (a thickening of the wall of the heart’s main pumping chamber) and left atrial dilation (a stretching out of the heart’s upper left chamber) have previously been shown to raise risk of stroke, heart attack and death in adults. In this study, adolescents with metabolic syndrome had a higher prevalence of both left ventricular hypertrophy and left atrial dilation compared with adolescents who did not have metabolic syndrome: 43.2% versus 11.7%, and 63.1% versus 21.9%, respectively.  Additionally, adolescents with metabolic syndrome displayed evidence of increased heart muscle stiffness, a potential precursor to developing heart failure over time.

Furthermore, a statistical analysis revealed that adolescents with all five components of the metabolic syndrome (increased waist circumference, low “good” HDL cholesterol, high blood pressure, high triglycerides, and elevated blood sugar) had a 2.6-fold greater risk of left ventricular hypertrophy and a 2.3-fold greater risk of left atrial dilation than those who only had individual components of the syndrome such as high blood pressure or obesity.  (You’re at risk for metabolic syndrome with three or more of the components mentioned above.)

“When you look at metabolic risk factors individually, they all have some negative influence on the heart, but when you consider the metabolic syndrome as a whole, it has an additional and independent impact on the heart, “says Dr. Chinali. “The high prevalence of [detrimental heart changes] really suggest that even if the patient is young, the presence of the metabolic syndrome should definitely suggest aggressive lifestyle modifications.” 

The study findings are published in the September 9, 2008 issue of the Journal of the American College of Cardiology.

Sources:

Chinali M. et al. Cardiac Markers of Pre-Clinical Disease in Adolescents With the Metabolic Syndrome. The Strong Heart Study.  Journal of the American College of Cardiology, 2008. 

Marcello Chinali, MD, Visiting Fellow, Weill Cornell Medical College, New York, New York.