SAGITTAL ABDOMINAL DIAMETER AS A PREDICTOR OF OBESITY

Obesity can cause major health implications, however, abdominal adiposity increases the risk of comorbidities, such as cardiovascular disease. Common methods for predicting weight and health risk in a clinical setting include body mass index (BMI) and waist circumference (WC). The purpose of this study was to investigate if sagittal abdominal diameter (SAD) was an appropriate measure of adiposity when compared to other measures of body composition in adults 50 years and older. Methods: Participants were 100 men (n = 38) and women (n = 62) aged 59 ± 7.6 years, who reported to the laboratory after refraining from food, water, and exercise for at least two hours. SAD was measured using an abdominal caliper (M:22.7 ± 3.1; F:21.9 ± 7.6 cm). Height and weight were assessed via stadiometer and calibrated electronic scale; BMI was calculated as kg/m2 (M: 27.4 ± 4.7; F:26.4 ± 5.9 kg/m2). WC was measured using a self-locking tape measure at two anatomical points; narrowest waist (WCN) (M: 93.2 ± 9.4; F: 83.4 ± 12.4 cm) and level with the umbilicus (WCU) (M: 97.1 ± 11.2; F: 90.6 ± 13.1 cm). Each participant completed body composition analysis via bioelectrical impedance analysis (BIA) (M: 23.3 ± 6.9; F: 33.4 ± 9.0 %) and air-displacement plethysmography (ADP) (M: 25.9 ± 7.0; F: 35.8 ± 8.9 %). Percent fat estimated by ADP was used as the criterion measure of body composition in this investigation. Results: When using a cut-point of <25 cm for SAD, 28% of participants were correctly classified as lean according to percent fat via ADP. Of the variables measured, BMI and WCU proved to be the best indicators of overweight/obesity, with BMI having a sensitivity value of 84% for all individuals, and WCU with a 70% sensitivity value. In addition to the published SAD cut-point, a lower cut-point was investigated. With a lower cut-point of ≤22 cm, sensitivity values increased to 78%. Conclusion: Based on the results in the current investigation, the SAD cut-point of <25 cm was not an accurate measure for obesity-related risk in men and women 50 years and older. Therefore, it is recommended that BMI and WCU provide stronger estimates than SAD with a cut-point of 25 cm of obesity-related health risk in adults 50 years and older.