Where should we measure waist circumference in clinically overweight and obese youth?

Aims: Waist circumference (WC) measurement is a useful tool in the assessment of overweight/obese individuals, but standard measures may miss an apron of 'overhanging' fat (termed 'panniculus'). The objective of this study was to assess whether, in clinically overweight/obese youth, 'pannicular' WC better correlates with fat mass than a standard WC measurement. Methods: Standard and pannicular WC, alongside body composition (BC) measures, were collected from 181 consultations on 127 overweight and obese children/adolescents (52% male; mean (standard deviation) age 12.5 (3.4) years). Correlation coefficients describe associations between WC and measures of BC, and between Delta WC and Delta BC, while linear regression models assessed which of the WC measures explained more of the variability in BC and Delta BC over time. Results: Standard and pannicular WC were highly correlated (r = 0.95). Correlation coefficients with measures of BC were generally greater for pannicular than standard WC, with greatest correlations seen for whole body (r = 0.94 vs. 0.85, respectively) and truncal (r = 0.86 vs. 0.77) fat mass. Furthermore, pannicular and Delta pannicular WC explained more variability in truncal fat and Delta truncal fat than the standard measure of WC. Conclusions: These data show that pannicular, rather than standard, WC measurements better correlate with absolute measures of fat mass, and their change over time, in clinically overweight/obese youth.