Malnutrition is associated with increased mortality in older adults regardless of the cause of death

Abstract

Malnutrition predicts preterm death, but whether this is valid irrespective of the cause of death is unknown. The aim of the present study was to determine whether malnutrition is associated with cause-specific mortality in older adults. This cohort study was conducted in Sweden and included 1767 individuals aged ≥65 years admitted to hospital in 2008-2009. On the basis of the Mini Nutritional Assessment instrument, nutritional risk was assessed as well nourished (score 24-30), at risk of malnutrition (score 17-23·5) or malnourished (score <17). Cause of death was classified according to the International Statistical Classification of Diseases and Related Health Problems, 10th Revision, into twenty different causes of death. Data were analysed using Cox proportional hazards regression models. At baseline, 55·1 % were at risk of malnutrition, and 9·4 % of the participants were malnourished. During a median follow-up of 5·1 years, 839 participants (47·5 %) died. The multiple Cox regression model identified significant associations (hazard ratio (HR)) between malnutrition and risk of malnutrition, respectively, and death due to neoplasms (HR 2·43 and 1·32); mental or behavioural disorders (HR 5·73 and 5·44); diseases of the nervous (HR 4·39 and 2·08), circulatory (HR 1·95 and 1·57) or respiratory system (HR 2·19 and 1·49); and symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (HR 2·23 and 1·43). Malnutrition and risk of malnutrition are associated with increased mortality regardless of the cause of death, which emphasises the need for nutritional screening to identify older adults who may require nutritional support in order to avoid preterm death.

Keywords: 10th Revision; HR hazard ratio; ICD-10 International Statistical Classification of Diseases and Related Health Problems; MNA Mini Nutritional Assessment; Cause-specific mortality; Cohort studies; Malnutrition; Older adults; Survival analyses.