Sarcopenia and hospital-related outcomes in the old people: a systematic review and meta-analysis

Aim This systematic review was conducted to explore the associations between sarcopenia, hospitalization and length of stay in the old people. Methods Pubmed, Embase, Medline and Cochrane Central Register of Controlled Trails from January 2009 to October 2017 were searched in this review. We included prospective studies, which had the clear definition of sarcopenia and reported the hospitalization or length of stay as one of outcomes. Adjusted Odd ratios (aORs), hazard ratios (aHRs) or relative risks (aRRs) extracted from the studies were combined to synthesize pooled effect measures. Heterogeneity, and methodological quality were assessed using I ² statistic and Newcastle–Ottawa scale, respectively. Results Nine studies were included in this review. Of these, 8 studies with 4174 individuals reported results for hospitalization, 3 studies involving 6276 old people in the community reported results for length of stay. Sarcopenia was significantly associated with future hospitalization (RR 1.40, 95% CI 1.04–1.89, p = 0.029; data from 8 studies). A subgroup analysis showed the associations between sarcopenia and readmission in hospitalized old patients that were statistically significant (RR 1.75, 95% CI 1.01–3.03, p = 0.044; data from 8 studies). However, this association were not found in the community-dwelling older subjects (RR 1.08, 95% CI 0.74–1.57, p = 0.688; data from 8 studies), uncertain in nursing home residents. The association of sarcopenia and length of stay was not statistically significant (OR 1.21, 95% CI 0.90–1.63, p = 0.20; data from 8 studies) in community-dwelling residents. Conclusions This systematic review demonstrates that sarcopenia is a significant predictor of readmission in old inpatients, but not associated with hospitalization or length of stay in community-dwelling old adults.