title: Skeletal muscle mass indices in healthy young Mexican adults aged 20-40 years: implications for diagnoses of sarcopenia in the elderly population.
abstract: OBJECTIVE
  Skeletal muscle and skeletal muscle indices in young adults from developing countries are sparse. Indices and the corresponding cut-off points can be a reference for diagnoses of sarcopenia. This study assessed skeletal muscle using dual-energy X-ray absorptiometry (DXA) in healthy male and female subjects aged 20-40 years and compared their appendicular skeletal muscle mass (ASM) and total-body skeletal muscle (TBSM) indices using certain cut-off points published in the literature.
  
  
  METHODS
  A sample of 216 healthy adults men and women from northwest Mexico was included. Body composition was assessed by DXA and several published DXA-derived skeletal muscle indices were compared.
  
  
  RESULTS
  Both, ASM and TBSM were higher in men compared to the women group (23.0 ± 3.4 versus 15.9 ± 1.6 kg; P < 0.05 and 26.5 ± 4.1 versus 16.9 ± 1.9 kg; P < 0.05, resp.). These differences were also valid for both indices. When derived cut-off points were compared with the most reported indices, significant differences were found.
  
  
  CONCLUSIONS
  Published cut-off points from Caucasians are higher than cut-off point derived in this sample of Mexican subjects. The new DXA-derived cut-off points for ASM proposed herein may improve diagnoses of sarcopenia in the geriatric Mexican population.
authors.affiliation: Coordinación de Nutrición, Centro de Investigación en Alimentación y Desarrollo (CIAD), A.C. Carretera a La Victoria Km. 0.6, 83304 Hermosillo, Sonora, Mexico.
authors.forename: H
authors.initials: H
authors.lastname: Alemán-Mateo
authors.affiliation: Coordinación de Nutrición, Centro de Investigación en Alimentación y Desarrollo (CIAD), A.C. Carretera a La Victoria Km. 0.6, 83304 Hermosillo, Sonora, Mexico.
authors.forename: Roxana E
authors.initials: RE
authors.lastname: Ruiz Valenzuela
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging*; D011859:Radiography; D055948:Sarcopenia / Q000000981:diagnostic imaging* / Q000453:epidemiology; D012737:Sex Factors