Sarcopenia and sarcopenic obesity in comparison: prevalence, metabolic profile, and key differences. A cross-sectional study in Italian hospitalized elderly.

BACKGROUND: The aim of this study is to identify the prevalence, assess the metabolic profile, and key differences (versus healthy) in a cohort of subjects with sarcopenia (S) and in sarcopenic obesity (SO) hospitalized elderly.

METHODS: A standardized comprehensive geriatric assessment was performed. We enrolled 639 elderly subjects (196 men, 443 women) with a mean age of 80.90 ± 7.77 years. Analysis of variance and a multinomial logistic regression analysis adjusting for covariates were used to assess the differences between groups.

RESULTS: The prevalence of (S) was 12.42% in women and 23.47% in men. (SO) was 8.13% in women and 22.45% in men. Data showed that either groups had a functional impairment (Barthel index < 50 points). (S) had the mean value of erythrocyte sedimentation rate (ESR) (>15 mm/h), CPR (>0.50 mg/dl) homocysteine (>12 micromol/l), and hemoglobin (<12 g/dl). Ferritin level over the range (>145 mcg/dl) was detected in either cohort (due to inflammation). (SO) had glycemia (>110 mg/dl). Key differences in (S) cohort (versus healthy) were a reduction in functional impairment (p < 0.001), an increase in white blood cell (p < 0.01), a decrease in iron level (p < 0.05), in electrolytes balance (Na: p < 0.01 and Cl: p < 0.01), and tyroid function (TSH: p < 0.001). In addition, (S) had higher state of inflammation (erythrocyte sedimentation rate: p < 0.05 and C-reactive protein: p < 0.01), and an increase of risk of fractures (FRAX: OR 1.07; p < 0.001), risk of malnutrition (mini nutritional assessment: p < 0.001), and risk of edema (extra cellular water: p < 0.001). In (SO) cohort, an increase in white blood cell (p < 0.001) and erythrocyte sedimentation rate (p < 0.05) was observed.

CONCLUSIONS: (S) subjects appears more vulnerable than (SO). Sarcopenia is closely linked to an increase in the risk of hip-femur fractures, inflammation, edema, and malnutrition. The (SO) subjects seem to benefit from the "obesity paradox."