Body fatness: longitudinal relationship of body mass index and the sum of skinfolds with other risk factors for coronary heart disease.

OBJECTIVE

To analyse the longitudinal relationships between body mass index (BMI)/sum of skinfolds (SSF) and biological and lifestyle risk factors for coronary heart disease (CHD).

DESIGN

An observational longitudinal study; that is, the Amsterdam Growth and Health Study.

SUBJECTS

181 males and females, initially aged 13 y. Over a period of 15 y, six repeated measurements were carried out.

MEASUREMENTS

BMI and SSF, biological CHD risk factors; that is, total cholesterol (TC), high density lipoprotein (HDL), TC:HDL ratio, systolic/diastolic blood pressure (SBP/DBP) and cardiopulmonary fitness (VO2-max) and lifestyle CHD risk factors (that is, daily physical activity, dietary parameters, smoking, and alcohol consumption). The longitudinal relationships were analysed by an autoregressive model, in which the value of the outcome variable at time-point t is not only related to the value of the predictor variable at t, but also to the value of the outcome variable at t-1.

RESULTS

Both BMI and SSF were positively related to TC and the TC:HDL ratio. Only BMI was positively related to SBP and only SSF was negatively related to VO2-max. Physical activity was negatively related to SSF. None of the other lifestyle parameters were related to SSF and/or BMI.

CONCLUSIONS

Both BMI and SSF were related to a high risk profile regarding CHD. Different relationships for SSF and BMI are found, because BMI not only reflects body fatness, but also lean body mass. Analyses with BMI as an indicator for body fatness should therefore be interpreted cautiously.