Relationships of cardiovascular phenotypes with healthy weight, at risk of overweight, and overweight in US youths.

OBJECTIVE

This study aimed to evaluate comprehensively the cardiovascular phenotypes of cardiovascular disease-free youths at risk of overweight, in comparison with healthy weight and overweight.

METHODS

Casual and ambulatory blood pressure measurements, noninvasive hemodynamic profiles, pulse wave velocity, left ventricular structure and function, and overnight sodium excretion were examined in a cohort of US black and white youths (n = 972; mean age: 17.6 +/- 3.3 years).

RESULTS

The occurrence of at risk of overweight was approximately 17% in either black youths or white youths. In white youths, there was a approximately 2-mmHg increase in casual systolic blood pressure for each increasing step in the 3 BMI categories (healthy weight, 109.5 +/- 0.5 mmHg; at risk of overweight, 111.5 +/- 0.6 mmHg; overweight, 113.5 +/- 1.1 mmHg). Ambulatory systolic blood pressure showed a similar increase with the increase in BMI. A blunted nocturnal decline in ambulatory diastolic blood pressure with the categorical BMI increase was observed in black youths. In both racial groups, cardiac output and stroke volume were significantly enhanced sequentially from healthy weight to at risk of overweight to overweight. In black youths, both casual and ambulatory heart rate increased significantly with the increase in BMI. Moreover, there was a linear increase of left ventricular mass index from the healthy-weight group to the at risk of overweight group, with the overweight group having the highest value. In white youths, carotid-dorsalis pedis pulse wave velocity increased significantly as the BMI increased. Regardless of race, overnight sodium excretion showed a significant increase from healthy-weight subjects to overweight subjects, with at risk of overweight subjects having intermediate values.

CONCLUSIONS

Youths at risk of overweight, compared with healthy-weight youths, seem to have increased cardiovascular risks. Our data suggest that the status of at risk of overweight already has clinical implications in youths.