Bone mineral density in familial partial lipodystrophy

Abstract

Objective: Type 1 and type 2 familial partial lipodystrophies (FPLD) are characterized by the loss or increase in subcutaneous fat in certain body regions, as well as metabolic disorders. Higher muscle volume and mass have also been described. However, so far, possible bone involvement has not been studied. The aim of this study was to evaluate bone mineral density (BMD) in patients with type 1 and type 2 FPLD.

Methods: A total of 143 women were selected and distributed into three groups (17 women with FPLD2, 82 women with FPLD1 and 44 nonlipodystrophic obese female controls). A thorough history and physical examination were carried out on all subjects, as well as the measurement of anthropometric features. BMD along with fat and fat-free mass (FFM) were determined by DXA (dual-energy X-ray absorptiometry). Statistical analyses, primarily using the χ² , ANOVA and ANCOVA tests, were performed, using age, height, fat and FFM as covariables.

Results: After eliminating the possible influences of age, height, fat and FFM, we observed that there were no significant differences in total BMD between patients with FPLD and the control group, showing total BMD values of 1.092 ± 0.037 g/cm² in the FPLD2 group, 1.158 ± 0.013 g/cm² in the FPLD1 group and 1.173 ± 0.018 g/cm² in the control group (P = .194). Similarly, no significant differences were found in segmental BMD.

Conclusions: Unlike in other types of laminopathy in which bone is affected, in the case of FPLD, there are no differences in BMD compared to nonlipodystrophic subjects.

Keywords: LMNA; body composition; bone density; dual-energy X-ray absorptiometry; familial partial lipodystrophy; laminopathies.