Abstract
Body composition measurements are used to evaluate surgical treatment, such as bariatric surgery in overweight patients. Nowadays, there are many different methods to measure body composition available. However, none of them has been validated for use in patients after operation. The aim of the present study was to compare the amount of surgically removed fat with two different methods, bioelectrical impedance analysis (BIA) and total body potassium (TBK). Amount of removed fat during liposuction was measured 1, 2, 3, 4, 14 days, and 1 year postoperatively in 27 obese patients after liposuction. The results were compared with actual removed fat during the operation. The median fat mass removed was 4020 grams (range 1954–9655). Postoperatively there was a varying reduction in fat mass, as measured with BIA and with TBK. There was a clear difference between the range of amounts removed measured with BIA and the range of amount removed measured with TBK. This study indicates that BIA, but not TBK, is an appropriate method to measure fat mass in obese subjects in a surgical setting. BIA seems to underestimate the amount of fat removed, whereas TBK seems to overestimate it.
Acknowledgements
The work was supported by grants from The Swedish Rheumatism Association, the insurance company Förenade Liv, Clinical Research and Development at Malmö University Hospital, Helge Wulff's Trust, and the Faculty of Medicine at the Lund University. We thank Associate Professor Bo Lilja and Dr Ola Thorsson and the Department of Clinical Physiology, Skåne University Hospital, Malmö for help with total body potassium (TBK) measurements.
Declaration of interest
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.