Nutritional and swallowing statuses but not intramuscular adipose tissue and muscle mass are related to activities of daily living in older inpatients who are judged as severely low body mass index in the Global Leadership Initiative on Malnutrition criteria

Which factors are related to activities of daily living (ADL) in older inpatients who are judged as the severely low body mass index (BMI) in the Global Leadership Initiative on Malnutrition (GLIM) criteria is unclear. This study aimed to examine the related factors to ADL in older inpatients who are judged as severely low BMI in the GLIM criteria. This cross-sectional study included 377 inpatients aged ≥70 years. We divided the participants into the following three groups: the severely low BMI group (<17.8 kg/m²) (n = 106), moderately low BMI group (≥17.8 to < 20.0 kg/m²) (n = 87), and normal BMI group (≥20.0 kg/m²) (n = 184). ADL were assessed using the motor-Functional Independence Measure (FIM). Multiple regression analyses were used to identify the factors independently associated with the motor-FIM score in each group. The Food Intake Level Scale (FILS) and Geriatric Nutritional Risk Index (GNRI) were significantly related to the motor-FIM score of the severely low BMI group. The FILS, GNRI, updated Charlson comorbidity index (UCCI), and quadriceps echo intensity were significantly related to the motor-FIM score of the moderately low BMI group. The FILS, GNRI, UCCI, quadriceps thickness, and subcutaneous fat thickness of the thigh were significantly related to the motor-FIM score of the normal BMI group. Our findings indicate that nutritional and swallowing statuses but not intramuscular adipose tissue and muscle mass are related to ADL in older inpatients who are judged as severely low BMI in the GLIM criteria. Intervention for nutritional and swallowing statuses may be prioritized over an exercise intervention to improve ADL of older inpatients who are judged as severely low BMI.