title: Premature loss of muscle mass and function in type 2 diabetes.
abstract: BACKGROUND
  Muscle mass and function are among the most relevant factors that contribute to an optimal quality of life, and are strong predictors of mortality in the elderly. Loss of lean tissues and deterioration of muscle function have been described as one of the many complications of type 2 diabetes mellitus (DM2), but most studies do not isolate age as an intervening factor.
  
  
  OBJECTIVE
  To study whether adult DM2 patients up to 60years of age have decreased muscle mass and function compared with healthy non-diabetic (ND) subjects of similar age.
  
  
  METHODS
  Appendicular fat-free mass (ApFFM) by dual X-ray absorptiometry (DEXA), handgrip strength (HS), quadriceps strength (QS), 12 min walking capacity (12MW) and the Timed Up and Go test (TUG) were measured in 100 DM2 patients and 39 ND controls. Muscle quality, or the ratio between lean mass and muscle strength of upper and lower limbs, and the functional limitations associated with pain and stiffness assessed according to the Western Ontario and McMaster Universities Arthrosis Index (WOMAC) were also recorded. Specific tests were performed to rule out microvascular diabetic complications (retinal and peripheral nerves), metabolic control, kidney function and vitamin D status and examine their association with ApFFM and function.
  
  
  RESULTS
  ApFFM was significantly higher among DM2 female patients and lower among diabetic men. However opposite results were obtained when individual values were corrected for body mass index (BMI), specifically among women, who were more likely to be obese. As for muscle strength and global functionality tests, significantly better performances in TUG, 12MW, QS and HS were observed among ND subjects of both sexes. These differences prevailed even after excluding diabetic patients with microvascular complications as well as those with more than 10years of diabetes. Muscle quality was also significantly better among ND women. Higher scores of pain and stiffness in the WOMAC scale correlated with 12MW and TUG in both groups but did not correlate with ApFFM.
  
  
  CONCLUSIONS
  We found a clear deterioration of lean mass and muscle functions among adult DM2 patients of up to 60years old, independent of length of disease, metabolic control, vitamin D status and presence of microvascular complications and pain.
authors.affiliation: Institute of Nutrition and Food Technology Dr. Fernando Monckeberg Barros (INTA), University of Chile, Chile.
authors.forename: N
authors.initials: N
authors.lastname: Guerrero
authors.affiliation: Institute of Nutrition and Food Technology Dr. Fernando Monckeberg Barros (INTA), University of Chile, Chile.
authors.forename: D
authors.initials: D
authors.lastname: Bunout
authors.affiliation: Institute of Nutrition and Food Technology Dr. Fernando Monckeberg Barros (INTA), University of Chile, Chile.
authors.forename: S
authors.initials: S
authors.lastname: Hirsch
authors.affiliation: Institute of Nutrition and Food Technology Dr. Fernando Monckeberg Barros (INTA), University of Chile, Chile.
authors.forename: G
authors.initials: G
authors.lastname: Barrera
authors.affiliation: Institute of Nutrition and Food Technology Dr. Fernando Monckeberg Barros (INTA), University of Chile, Chile.
authors.forename: L
authors.initials: L
authors.lastname: Leiva
authors.affiliation: Institute of Nutrition and Food Technology Dr. Fernando Monckeberg Barros (INTA), University of Chile, Chile.
authors.forename: S
authors.initials: S
authors.lastname: Henríquez
authors.affiliation: Institute of Nutrition and Food Technology Dr. Fernando Monckeberg Barros (INTA), University of Chile, Chile. Electronic address: mpmaza@inta.uchile.cl.
authors.forename: M P
authors.initials: MP
authors.lastname: De la Maza
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D016022:Case-Control Studies; D048909:Diabetes Complications / Q000175:diagnosis / Q000209:etiology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D009864:Ontario; D011788:Quality of Life; D055948:Sarcopenia / Q000175:diagnosis / Q000209:etiology*; D016138:Walking
keywords: Appendicular fat-free mass; Diabetes; Dual X-ray absorptiometry; Handgrip strength; Muscle quality; Sarcopenia