Malnutrition, functional ability and mortality among older people aged ⩾60 years: a 7-year longitudinal study

Abstract

BACKGROUND/OBJECTIVES: This study aimed to assess the association between risk of malnutrition and 7-year mortality, controlling for functional ability, socio-demographics, lifestyle behavior and diseases, and investigate the interaction between risk of malnutrition and functional ability on the risk of mortality. SUBJECTS/METHODS: A longitudinal study on home-living and special-housing residents aged [greater than or equal to] 60 years was conducted. Of 2312 randomly invited participants, 1402 responded and 1203 provided information on both nutritional status and functional ability. The risk of malnutrition was estimated by the occurrence of at least one anthropometric measure (BMI, MAC and CC) below cut-off in addition to the presence of at least one subjective measure (decreased food intake, weight loss and eating difficulty). RESULTS: At baseline, 8.6% of subjects were at risk of malnutrition and during the 7-year follow-up 34.6% subjects died. The risk of malnutrition was independently associated with 7-year mortality (hazard ratio (HR) 1.84, 95% confidence interval (CI) 1.28-2.65). Additional independent predictors were dementia (HR 2.76, 95% CI 1.85-4.10), activity of daily living (ADL) dependence (HR 2.08, 95% CI 1.62-2.67), heart disease (HR 1.44, 95% CI 1.16-1.78), diabetes (HR 1.41, 95% CI 1.03-1.93) and older age (HR 1.09, 95% CI 1.07-1.10). Moreover, the risk of malnutrition and ADL dependence in combination predicted the poorest survival rate (18.7%, P < 0.001). CONCLUSIONS: The risk of malnutrition significantly increases the risk of mortality in older people. Moreover, risk of malnutrition and ADL dependence together explain a significantly poorer survival rate; however, the importance of this interaction decreased in the multivariable model and risk of malnutrition and ADL dependence independently explained a significant risk of mortality.