Endocrine Abstracts

Introduction: Eligibility for bariatric surgery in the Unighted Kingdom is based on specific body mass index (BMI) thresholds and the presence of obesity-associated complications. Patients with partial lipodystrophy (LD) often have an abundance of metabolic and cardiovascular complications, but their abdominal adiposity does not always substantially increase BMI. The consequence is that patients with LD may be inappropriately excluded from obesity treatments when judged by BMI alone. We have therefore performed a detailed analysis of body composition in a large cohort of obese individuals and patients with LD to develop an algorithm to reflect the relative adiposity of the two groups.

Methods: A cohort of women with a BMI>40 kg/m² from the Oxford Biobank who had undergone dual X-ray absorptiometry (n = 55) to obtain absolute measurements of regional fat masses were analysed, along with 7 female patients with Familial Partial Lipodystrophy (types 2 and 3) and patients with partial lipodystrophy without an identified genetic mutation.

Results: For a given degree of android fat mass, all LD patients had a corresponding BMI that was below the 5^th percentile of regularly obese patients. Two LD patients underwent bariatric surgery and, during the weight loss phase, their repeated dual X-ray absorptiometry measurements continued to track below the 5^th percentile.

Conclusion: The use of BMI cut offs for prioritisation for bariatric surgery (or other weight loss treatments) in LD patients vastly underestimates the degree of android adiposity. The data we provide enables the estimation of the “true” BMI of LD patients if their adipose tissue fat mass were to be evenly distributed. The data also argue against using strict BMI cut offs for prioritization for weight loss interventions such as bariatric surgery.