Original Research Article
Year: 2017 | Month: Aug | Volume: 7 | Issue: 8 | Pages: 34-43
Skeletal Muscle and Metabolic Risk in Overweight Adolescents. An Indicator of Premature Sarcopenic Obesity
António Videira-Silva1,2, Helena Fonseca2,3
1Lisbon Academic Medical Centre (CAML), Lisbon, Portugal;
2Pediatric Obesity Clinic, Department of Pediatrics, Hospital de Santa Maria, Lisbon, Portugal;
3Rheumatology Research Unit, Molecular Medicine Institute, Faculty of Medicine, University of Lisbon, Lisbon, Portugal.
Corresponding Author: António Videira-Silva
ABSTRACT
Purpose: This study aimed to investigate the association between relative SMM (%SMM) and metabolic outcomes in overweight adolescents, and analyze the prevalence of overweight adolescents with decreased levels %SMM, based on reference charts for youth.
Methods:Clinical records from 240 overweight adolescents (BMI ≥ p85), aged 10-17, were collected retrospectively. From those, a sub-sample of 45 was used to analyze overtime changes in %SMM, anthropometric, metabolic and PA outcomes.
Results: %SMM was negatively associated with all the anthropometric variables, relative BFM (%BFM) (p<.001) and with Triglycerides (p<.01), and positively associated with PA levels (p<.001). Overtime decrease in %SMM percentile, was associated with increased %BFM (F=18.3, p<.001) and CRP (F=5.54, p<.05), and decreased HDL-C (F=4.37, p<.05) and PA levels (F=6.54, p<.01).
56 patients (26.9%) were classified ≤p25 for %SMM, showing higher BMI z-score, waist circumference, %BFM (p<.001), insulin, HOMA-IR (p<.01), Total cholesterol (p<.05), LDL-C (p<.01), Triglycerides (p<.001) and CRP (p<.05); and lower HDL-C (p<.05) and PA (p<.001) levels.
Conclusions: Body composition assessment together with the use of a p25 cut-off for %SMM, may act as a prior assessment of metabolic risk in overweight adolescents. Overweight adolescents at p25 or below for %SMM, may experience a deleterious effect of the combination of decreased %SMM levels and obesity-related metabolic outcomes, similarly to what happens with sarcopenic obesity, thus should be identified as a priority target for PA intervention.
Key words:Adolescent; Overweight; Body composition; Skeletal muscle mass; Metabolic risk; Sarcopenic obesity.