Changes in muscle strength and physical function in older patients during and after hospitalisation: a prospective repeated-measures cohort study

Abstract Aim to investigate changes in knee-extension strength and physical function in older adults during and after acute hospital admission, and the contributions of illness severity, frailty and sedentary activity to changes in knee-extension strength. Methods prospective repeated-measures cohort study on a sample of participants aged ≥75 recruited within 24 hours of acute hospital admission. Knee-extension, grip strength and functional mobility (de Morton Mobility Index, DEMMI) were measured at recruitment, day 7 (or discharge if earlier), and at follow-up 4–6 weeks later. During the first 7 days, continuous measurement of physical activity and daily measurements of muscle strength were taken. Participants recalled the functional ability they had 2-weeks before admission and self-reported it at follow-up (Barthel Index, BI). Results sixty-five of 70 participants (median age 84 years) had at least one repeated measure of muscle strength in hospital. Knee-extension strength declined during hospitalisation by 11% (P