Calf Circumference: A Marker of Muscle Mass as a Predictor of Hospital Readmission

Hospital readmissions (HRs) are common, potentially preventable, and a marker of poor quality in health services. This study aimed to identify risk factors for HR in clinical patients, with an emphasis on nutrition aspects, especially calf circumference (CC), as a marker of muscle mass. A prospective cohort study of patients admitted to the internal medicine ward was conducted. The short form of the Patient-Generated Subjective Global Assessment was performed in the first 24 hours of hospitalization. In addition, single-frequency bioelectrical impedance analysis was used to estimate the phase angle, CC as a surrogate of muscle mass, and handgrip strength as a marker of strength. The Charlson Comorbidity Index (CCI) was used to assess the severity of the comorbidities. Reassessments were performed every 7 days during hospitalization. HR was evaluated 30 days after discharge by phone contact. A sample of 161 patients was assessed; 54.6% were male, with a mean age of 59.2 ± 17.8 years. The median CCI was 2.76 (interquartile range: 1-4), and nutrition risk and low CC were present in 77.6% and 46% of the patients, respectively. The readmission rate was 16.8% after 30 days. After controlling for sex and age, a CCI > 2 (odds ratio [OR]: 3.29; 95% confidence interval [CI]: 1.21-8.97), the presence of cancer (OR: 4.52; 95% CI: 1.11-18.42), nutrition risk (OR: 9.53; 95% CI: 1.16-77.9), and a low CC (OR: 3.89; 95% CI: 1.34-11.31) were significantly associated with 30 day HR. In conclusion, muscle mass loss, identified by CC, can be a good predictor of 30-day HR, even after controlling for other well-known risk factors.