Altered body composition in type 2 diabetes mellitus

Abstract

Objective: To identify differences in amount and distribution of fat and lean soft tissue in a cross-sectional study of subjects with and without type 2 diabetes and to determine whether any differences are affected by race/ethnicity or sex.

Design and methods: Overweight and obese (body mass index, BMI > or = 25 kg m(-2)) Black, White and Hispanic men (490) and women (825) with type 2 diabetes ((mean+/-s.d.) age 58.5+/-6.6; BMI 35.3+/-5.3) who had a baseline dual energy X-ray absorptiometry whole-body scan at the time of enrollment in the Look AHEAD clinical trial, and 242 healthy controls, 91 males and 151 females (age 55.3+/-8.6 years, BMI 30.7+/-4.2 kg m(-2)) who were participating in unrelated research and were scanned on the same densitometers.

Results: Adjusted for gender, age, race, clinical site and body size, total fat mass was smaller in persons with type 2 diabetes than in controls (-1.4+/-0.3 (s.e.); 34.5 vs 35.8 kg, P<0.001) while trunk fat was larger (1.3+/-0.2 (s.e.); 19.9 vs 18.6 kg, P<0.001) and leg fat was smaller (-1.5+/-0.2 (s.e.); 10.7 vs 12.3 kg, P<0.001). The arms of subjects with type 2 diabetes did not have significantly less fat compared to controls. Adjusted trunk lean mass was larger in type 2 diabetes by 0.6 kg (28.4 vs 27.8 kg, P<0.001) while leg lean was smaller by 0.5 kg (18.1 vs 18.6 kg, P<0.001).

Conclusions: Type 2 diabetes is associated with less total fat, leg fat and leg lean mass and more truncal fat and lean mass than controls. The physiological processes producing these deviations in tissue distribution and their metabolic significance warrant further investigation.

Figure 1

Relationship of whole body fat mass to body weight in type 2 diabetes (left panel) and control (right panel) groups.

Figure 2

Mean differences between fat and lean masses adjusted for covariates (gender, race, total fat or lean mass, height, age and 2 and 3-way interactions, if any) in leg, trunk and arm regions of type 2 diabetes and control subjects, with control values as the zero reference. ArmFat_W and ArmFat_M is arm fat for women and men, respectively.