Association between hospitalization-related outcomes, dynapenia and body mass index: The Glisten Study

Objective: To compare the prognostic value of dynapenia, as evaluated by handgrip, and body mass index (BMI) on length of stay (LOS), days of bed rest, and other hospitalization-related outcomes in a population of older adults admitted to 12 italian acute care divisions. Methods: Data on age, weight, BMI, comorbidities, ADL, physical activity level, muscle strength, were recorded at hospital admission. LOS, days of bed rest, intrahospital falls, and discharge destination were also recorded during the hospitalization. Subjects with BMI <18.5 kg/m² were classified as underweight, subjects with BMI 18.5–24.9 as normal weight, subjects with BMI ≥25 as overweight-obese. Results: A total of 634 patients, mean age 80.8 ± 6.7 years and 49.4% women, were included in the analysis. Overall dynapenic subjects (D) showed a longer period of LOS and bed rest compared with non-dynapenic (ND). When the study population was divided according to BMI categories, underweight (UW), normal weight (NW), and overweight-obese (OW-OB), no significant differences were observed in hospital LOS and days of bed rest. When analysis of covariance was used to determine the difference of LOS across handgrip/BMI groups, D/OW-OB and D/UW subjects showed significantly longer LOS (11.32 and 10.96 days, both p 0.05) compared to ND/NW subjects (7.69 days), even when controlling for age, gender, baseline ADL, cause of hospitalization and comorbidity. After controlling for the same confounding factors, D/OW-OB, D/NW and D/UW subjects showed significantly longer bed rest (4.7, 4.56, and 4.05 days, respectively, all p 0.05, but D/OW-OB p 0.01) compared to ND/NW subjects (1.59 days). Conclusion: In our study population, LOS is longer in D/UW and D/OW-OB compared to ND/NW subjects and days of bed rest are mainly influenced by dynapenia, and not by BMI class.