Effect of anaemia on hand grip strength, walking speed, functionality and 1 year mortality in older hospitalized patients

Etienne Joosten, Elke Detroyer, Koen Milisen

Anaemia is a common problem in hospitalized older patients and is recognized as a risk factor for a significant number of adverse outcomes. Data of the effect of anaemia on functional status during hospitalization and mortality after discharge are limited. Aim of the study is to examine whether there is an association between anaemia, hand grip strength, gait speed and basic activities of daily living (ADL) during hospitalization and mortality 1 year after discharge in geriatric patients. In a prospective study, data on age, sex, body mass index, Mini-Mental State Examination (MMSE), main clinical diagnosis, number of comorbidities, hand grip strength, gait speed, ADL, haemoglobin, C-reactive protein and estimated Glomerular filtration ratio (eGFR) were recorded in 220 older patients, admitted to the acute geriatric ward of a university hospital. Anaemia was defined as a haemoglobin level <13 g/dL for men and <12 g/dL for women and was further specified into severe (haemoglobin level <10 g/dL for both men and women) and moderate anaemia (haemoglobin between 10 and 12 g/dL for women and 10 and 13 g/dL for men). Gait speed (in meters per second) was calculated after a 4.5 m walk and hand grip strength (in kilogram) was assessed with a hydraulic hand dynamometer. Functionality was assessed in the six basic activities of daily living. Information about the vital status was obtained 1 year after discharge with a telephone call. Analysis of covariance (ANCOVA) was used to examine the effect of the anaemia status on the walking speed, hand grip strength and premorbid ADL index and logistic regression analysis was used to examine whether anaemia could be identified as risk factors for mortality 12 months after discharge. Overall, 106 (48 %) patients had anaemia. Hand-grip strength, gait speed and ADL score were not significantly different between anaemic and non-anaemic hospitalized geriatric patients. After adjustment for age, sex, body mass index, eGFR, MMSE, number of comorbidities and main clinical diagnosis, the means for hand-grip strength were 17.3, 19.9 and 19.1 kg (p = 0.38); for gait speed 0.57, 0.52 and 0.47 m/s (p = 0.28); and for the ADL score 3.50, 3.05 and 3.30 (p = 0.75) in patients with severe, moderate and without anaemia, respectively. In the unadjusted model, the odds ratio for mortality 1 year after discharge was 2.72 (95 % CI 1.20-6.14) and 4.70 (95 % CI 1.91-11.77) for moderate and severe anaemia, respectively, with no anaemia as the reference group. After adjustment for several confounders, a haemoglobin level less than 10 g/dl (OR 3.87; 95 % CI 1.25-11.99) remained significantly associated with an increased mortality over that 1 year period. Our results do not support that anaemia on admission is associated with a decline in physical performance (hand grip strength and gait speed) and functionality (ADL) during hospitalization in older patients. However, severe anaemia is a significant risk factor for an increased mortality over a 1 year period after discharge.