Changes in skeletal muscle and organ size after a weight-loss intervention in overweight and obese type 2 diabetic patients

Abstract

Background: The effect of a weight-loss intervention on the masses of lean tissues and organs in humans is not well known. Objective: We studied the effects of a diet and exercise weight-loss intervention on skeletal muscle (SM) mass and selected organs over 2 y using MRI in overweight adults with type 2 diabetes. Design: Participants were 53 women and 39 men [mean 6 SD: age 58 6 7 y; body mass index (BMI; in kg/m 2 ) 32 6 3] enrolled in the Look AHEAD (Action for Health in Diabetes) trial and randomly assigned to an intensive lifestyle intervention (ILI) or diabetes support and education (DSE) on whom 2 y of data were collected. MRI-derived measurements of SM, heart, liver, kidney, spleen, and pancreas were acquired. Results: Adjusted for baseline weight, height, age, sex, and ethnicity, the ILI group weighed (mean 6 SE) 6.6 6 0.7 kg less after 1 y and 5.2 6 0.7 kg less after 2 y, whereas the DSE group did not change significantly (20.4 6 0.6 and 21.0 6 0.7 kg after 1 and 2 y, respectively; P-interaction , 0.001). Total SM decreased in both groups during year 1 (21.4 6 0.2 kg; P , 0.001) with appendicular SM regained during year 2. Liver and spleen masses decreased in the ILI group (20.12 6 0.02 and 20.006 6 0.003 kg, respectively) but were unchanged in the DSE group (0.00 6 0.02 and 0.004 6 0.003 kg, respectively). Kidney mass decreased by 0.013 6 0.003 kg (P , 0.001) over 2 y in both groups. Conclusions: Decreases in liver (in Caucasians but not African Americans) and spleen were detected after a 6.2-kg weight reduction compared with a control group. SM and kidney mass decreased in both groups. Appendicular SM was regained during the second year whereas trunk SM was not. No evidence of a disproportionate loss of high-metabolic rate organs (heart, liver, kidney, spleen) compared with SM was found.Am J Clin Nutr 2017;105:78-84.

Larger organ size caused by obesity is a mechanism for higher cancer risk

“…In a study by Gallagher et al 41 , overweight and obese adults with type 2 diabetes were enrolled in a weight-loss intervention program. At the study baseline, the women weighed on average 82 ± 14 kg, and had an average liver weight of 1.76 ± 0.50 kg; the men weighed on average 93 ± 8 kg, and had an average liver weight of 1.90 ± 0.40 kg.…”

“…In a study by Gallagher et al, overweight and obese adults with type 2 diabetes were enrolled in a weight-loss intervention program. At the study baseline, the women weighed on average 82 ± 14 kg, and had an average kidney weight of 0.38 ± 0.11 kg; the men weighed on average 93 ± 8 kg, and had an average kidney weight of 0.46 ± 0.08 kg 41 . After two years of weight-loss intervention, the subjects weighed on average 5.21 ± 0.74 kg less while MRI-derived measurements showed that their kidney weighed 0.02 kg less.…”

Current body composition measurement techniques

“…Adults with type 2 diabetes whose body weight did not change over a 2-year period (−0.44±0.60 kg) experienced a significant loss in skeletal muscle (by MRI) (1.2±0.2 kg) [31 ■■ ]. Andersen et al reported that, for patients with facioscapulohumeral muscular dystrophy type 1 (FSHD), a condition that is characterized by asymmetrical and progressive wasting of leg muscles, leg MRI was able to detect disease progression before the clinical test of functional outcomes (such as FSHD score, muscle strength by hand-held dynamometry, walking, or step-stair tests) [32].…”

Multiorgan, Multimodality Imaging in Cardiometabolic Disease

“…Scheuermann-Freestone and colleagues demonstrated one of the earliest multi-organ approaches to detect subclinical metabolic abnormalities in diabetic individuals without evident cardiovascular disease, incorporating exercise 31 PMRS in skeletal muscle with multimodality cardiac imaging and spectroscopy 66 . Gallagher et al showed reduced mass of the liver and spleen in obese T2DM subjects using whole body T1-weighted MRI in a prospective lifestyle intervention trial, though tissue characterization was not performed to know if mass reduction was effected via reduced fat in these organs 67 . Combining phosphorus and hydrogen cardiac MRS with PET and dobutamine stress echocardiography in a randomized clinical trial of pioglitazone vs. metformin, van der Meer et al demonstrated the potential of a multimodality, multiorgan approach to refine therapeutic strategies for CMD 68 .…”