Sarcopenia and mortality risk in frail older persons aged 80 years and older: results from ilSIRENTE study

Background and aims: sarcopenia has been indicated as a reliable marker of frailty and poor prognosis among the oldest individuals. We evaluated the impact of sarcopenia on the risk of all-cause death in a population of frail older persons living in community. Methods: we analysed data from the Aging and Longevity Study, a prospective cohort study that collected data on all subjects aged 80 years and older residing in the Sirente geographic area (n=364). The present analysis was conducted among those subjects who were between 80 and 85 years of age at the time of the baseline assessment (n=197). The main outcome measure was all-cause mortality over 7-year follow-up. According to the European Working Group on Sarcopenia in Older People (EWGSOP) criteria, the diagnosis of sarcopenia required the documentation of low muscle mass and the documentation of either low muscle strength or low physical performance. Cox proportional regression models were used to estimate crude and adjusted hazard ratios and 95\% confidence intervals of death by the presence of sarcopenia. Results: using the EWGSOP-suggested criteria, 43 subjects with sarcopenia (21.8\%) were identified. During the 7-year follow-up, 29 (67.4\%) participants died among subjects with sarcopenia compared with 63 subjects (41.2\%) without sarcopenia (P<0.001). After adjusting for potential confounders including age, gender, education, activities of daily living (ADL) impairment, body mass index, hypertension, congestive heart failure, chronic obstructive pulmonary disease, number of diseases, TNF-alpha, participants with sarcopenia had a higher risk of death for all causes compared with non-sarcopenic subjects (HR: 2.32, 95\% CI: 1.01-5.43). Conclusions: our results obtained from a representative sample of very old and frail subjects show that sarcopenia is associated with mortality independently of age and other clinical and functional variables.