Abstract 10: Determinants Of In-hospital Muscle Loss In Acute Ischemic Stroke - Results Of The Muscle Assessment In Stroke Study (MASS)

Abstract

Background: Recent literature, primarily based on chronic stroke patients, highlighted a change in the mass and composition of paretic and non-paretic skeletal muscles following stroke. The multi-center, prospective, and observational Muscle Assessment in Stroke Study (MASS; ClinicalTrials.gov ID: NCT03825419) was performed to evaluate the degree of muscle loss during the in-hospital acute stroke setting and determine factors contributing to this loss, especially from the perspective of protein/calorie intake. Methods: Acute dysphagic ischemic stroke patients admitted to neuro-intensive care units were evaluated by computed tomography on days 1 and 14 after admission to determine the cross-sectional muscle area (CSMA) at the level of the mid-humerus, mid-thigh, and third lumbar vertebra. The percentage change in CSMA and variables associated with this change were evaluated by univariate and multivariate analyses. Results: The study population was comprised of 107 patients [median (IQR) age:74 (63-82) years; 58 females]. There were significant reductions in CMSA in all the muscle groups analyzed; the most prominent change was observed in the arms (both: 14.2±10.7%; paretic: 17.7±11.6%; non-paretic: 10.1±12.5%), followed by the muscles in the legs (both: 12.4±8.7%; paretic: 12.9±9.9%; non-paretic: 12.0±9.3%) and L3-vertebra level (5.6±9.8%) (p<0.001 for all). The percent reduction in CSMA of the arms was associated with an unfavorable outcome (90-day mRS≥3) when adjusted for age and admission stroke severity [OR 1.13 (1.04-1.23) for each 1% reduction in CSMA; p=0.003]. The presence of a significant protein (≥0.4 g/kg/d) or calorie (≥5kcal/kg/d) gap between targeted or actual intake was related to a larger decrease in CSMA in all the anatomic regions evaluated (p≤0.05 for all). Other significant predictors of muscle loss included a history of diabetes mellitus, male sex, higher body mass index, in-hospital infections, and the necessity for invasive mechanical ventilation. Conclusions: There is a considerable degree of loss in the global muscle mass in acute ischemic stroke patients over a two-week period. Along several factors, falling significantly behind the daily protein or calorie targets was related to the decrease in muscle area.