Blood pressure and body composition in children: importance of allowing for cuff size.

A cross-sectional study of blood pressure (BP) was conducted in a sample of 1312 Australian school children aged 11-12 yrs. In line with current recommendations for the measurement of BP, a cuff of appropriate size was chosen for each subject based on his or her arm circumference. Analyses revealed statistically significant independent relationships between measured BP and cuff size. Observed relationships in the sample between measured BP and body composition variables were substantially affected when BP measurements were adjusted to remove the effect of cuff size. Cuff-associated biases in estimates of relationships between BP and body composition variables may still exist even though cuffs are carefully chosen to suit arms of different circumferences. It would appear that this potential problem is largely unrecognised. Some previous studies of relationships between BP and body composition may have been affected.