The Impact of Frailty, Activity of Daily Living, and Malnutrition on Mortality in Older Adults with Cognitive Impairment and Dementia.

BACKGROUND

Malnutrition contributes to frailty dementia, intensifying adverse health outcomes including mortality risk.

OBJECTIVES

We aim to investigate the impact of malnutrition risk in those with frailty and functional decline on short-term mortality among older adults with dementia and/or cognitive impairment.

METHODS

We conducted a retrospective cohort study involving 2677 hospitalized patients aged ≥65 years with a diagnosis of dementia or cognitive impairment discharged between March 2022 and December 2023. Information was obtained from electronic medical records. Frailty was assessed using the Clinical Frailty Scale (CFS) and Hospital Frailty Risk Score (HFRS), functional status using premorbid activity of daily living (ADL) scores, and malnutritional risk using the 3-Minute Nutrition Screening (3-Min NS) tool. Associations with 30- and 90-day mortality were examined using Kaplan-Meier analysis and multivariate logistic regression models.

RESULTS

A total of 29.2% were at risk of malnutrition, highest in the old-old (37.1%). Thirty-day mortality was significantly associated with CFS (aOR = 1.498, 95% CI: 1.349-1.664, < 0.001), HFRS (aOR = 1.020, 95% CI: 1.001-1.040, = 0.038), and ADL (aOR = 0.819, 95% CI: 0.753-0.890, < 0.001). Malnutrition risk demonstrated the strongest association across all models (ADL: aOR = 2.573, 95% CI: 1.922-3.443, < 0.001; CFS: aOR = 2.348, 95% CI: 1.738-3.156, < 0.001; HFRS: aOR = 2.944, 95% CI: 2.210-3.922, < 0.001). Associations between 90-day mortality and malnutrition risk remained significant across all models, including those adjusted for CFS and ADL. Notably, interactions between malnutrition and CFS further amplified mortality risk among the old-old (30-day: aOR = 1.435, 95% CI: 1.082-1.902, = 0.012; 90-day: aOR = 1.263, 95% CI: 1.005-1.588, = 0.045).

CONCLUSIONS

Risk of malnutrition independently predicted short-term mortality in older adults with dementia or cognitive impairment, particularly among those with frailty, functional decline, and of advanced age.