Neck and waist circumference biomarkers of cardiovascular risk in a cohort of predominantly African-American college students: a preliminary study.

Receiver operating characteristic curves were constructed to assess the value of measuring neck and waist circumference and waist-to-hip ratio (WHR) as biomarkers of metabolic syndrome in college students (18 to 25 years of age). Participants (n=109) were 92% black, 62.4% female, 45.9% overweight or obese, and 20.2% prehypertensive or hypertensive. Overall, 41 (37.6%) students had one or more risk factors for metabolic syndrome. Percent body fat, assessed using whole-body air-displacement plethysmography, was positively correlated (P<0.0001) with neck and waist circumference (as measured at the midpoint between the right lower rib and suprailiac crest; hereafter "midpoint"). Neck circumference correlated with low-density lipoprotein cholesterol (P ≤ 0.02) and both neck circumference and waist circumference-midpoint correlated with insulin (P ≤ 0.001) and triglycerides (P ≤ 0.002). The best-fit cutoffs were ≥ 83 cm waist circumference-midpoint and ≥ 88 cm waist circumference measured at the suprailiac crest for percent body fat in men and ≥ 75 cm waist circumference-midpoint for metabolic syndrome in women. The proportion of overweight and prehypertensive individuals among self-described healthy students underscores the need for screening tools that identify those who might benefit most from health interventions. Waist circumference-midpoint provides a simple yet sensitive method for the estimation of percent body fat and metabolic syndrome risk in primarily African-American college students. The novel use of neck circumference should be further investigated.