Factor analysis of clustered cardiovascular risks in adolescence: obesity is the predominant correlate of risk among youth.
BACKGROUND
Clustering of cardiovascular (CV) risks begins in childhood, yet studies of the factor structure underlying this clustering have focused on adults. The increasing rates of obesity and type 2 diabetes and the growing importance of metabolic syndrome among adolescents make assessment of CV risk clustering even more urgent in this age group.


RESULTS
Exploratory factor analysis (principal components analysis) was performed with data from 1578 healthy seventh to 12th graders from the Princeton School District Study, a school-based study in Cincinnati, Ohio. Measured CV risks included cholesterol, triglycerides, fasting insulin and glucose, body mass index (BMI), waist circumference, fibrinogen, and blood pressure. Factor analysis yielded 4 uncorrelated factors (adiposity [BMI, waist, fibrinogen, insulin], cholesterol [LDL and total cholesterol], carbohydrate-metabolic [glucose, insulin, HDL cholesterol, triglycerides], and blood pressure [systolic and diastolic blood pressure]). These factors explained approximately 67% of the total variance. A summary cumulative risk scale was derived from factor scores, and high risk was defined as scoring in the top 5%. Although insulin loaded onto both the adiposity and carbohydrate-metabolic factors, obesity was a much stronger correlate of high cumulative risk (odds ratio=19.2; 95% CI, 7.6 to 48.5) than hyperinsulinemia (odds ratio=3.5; 95% CI, 1.8 to 6.8). A sizable proportion (18.5%; n=12) of those who were at high cumulative risk were not at high risk for any of the individual factors.


CONCLUSIONS
The patterning of CV risk clustering seen among adults is present in healthy adolescents. Among youth, obesity is the predominant correlate of cumulative risk.
Goodman
Elizabeth
E
Heller School for Social Policy and Management, Brandeis University, MS 35, 415 South St, Waltham, MA 02453-9110, USA. goodman@brandeis.edu
Dolan
Lawrence M
LM
Morrison
John A
JA
Daniels
Stephen R
SR
D000293:Adolescent; D001837:Body Weights and Measures; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000209:etiology; D016000:Cluster Analysis; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D024821:Metabolic Syndrome; D009765:Obesity / Q000150:complications / Q000453:epidemiology*; D012307:Risk Factors
D008055:Lipids