Utility of Sonographic Parameters in Prediction of Obesity and their Correlation with Body Mass Index

Abstract

Introduction: Obesity has become widely prevalent in the world with a desperate need to search the population at risk for complications of obesity for timely intervention. Ultrasonography (USG) has been previously used to measure the Subcutaneous Abdominal Fat Thickness (SAFT); however, its role has not been adequately defined. Aim: To establish the role of USG as a quantitative measure of obesity by measurement of SAFT and Skin Thickness (ST). Materials and Methods: The study was done on a total of 406 patients. Body Mass Index (BMI) was calculated for all the patients who were categorised into four pre defined BMI based subgroups. The patients then underwent USG measurement of SAFT and ST. Statistical analysis with intergroup comparison was done using one-way ANOVA test. Results: Of the total, 146 patients had BMI≥25 kg/m2 and belonged to the obese category. Mean values of SAFT and ST showed statistically significant results. Box and whiskers plots for all the variables showed least overlapping of the Interquartile Range (IQR) for SAFT. SAFT showed significantly higher median value for the overweight and obese categories. SAFT showed highest area under the curve with 79% sensitivity and 72% specificity for prediction of obesity (BMI≥30 kg/m2 ) at a value of 18.65 mm. SAFT showed the strongest correlation with increasing BMI. Conclusion: The findings of the present study showed that USG is an excellent modality for the measurement of SAFT and ST which may be useful in future epidemiological studies. Addition of these sonographic parameters may significantly enhance the prediction and categorisation of adiposity over other anthropometric variables like BMI.

Keywords

• body mass index
• skin thickness
• subcutaneous abdominal fat thickness
• ultrasonography