Impact and Clinical Implications of the Cognitive Function and Nutritional Assessment at Admission on Hospital Outcomes and Mortality in Acutely Ill Geriatric Patients

Author(s): Hiroshi Yamamoto, Kenichi Ogawa, Kazuo Matsuo, Yasushi Hisamatsu, Tatsuya Ishitake.

Background: The nutritional and mental status of older patients are closely related and may serve as an indicator of hospital outcomes and early nutrition interventions.

Objective: We aim to appraise the impact on mortality and hospital outcomes by the revised simplified short-term memory recall test (STMT-R) and the short-form mini-nutritional assessment (MNA-SF) simultaneously at admission.

Methods: The subjects were 727 acute inpatients with ≥50 years of age from December 2014 to September 2015. Following the collection of clinical data (base illness, length of stay, etc.), survival was subsequently measured for 4-5 years until September 2019. An STMT-R score of ≤4 and MNA-SF score ≤7 were considered to indicate cognitive dysfunction and malnourishment respectively. Cox’s proportional hazards regression models were used to evaluate the hazard of death according to the severity of dementia and the nutrition status, with adjustment for potential covariates. Survival was estimated using the Kaplan-Meier method.

Results: The mean age of the study population was 78.9(±10.2) and 52.7% of the patients were female. 118 patients could not complete the cognitive test (Incomplete Testing Group [ITG]). 385 and 224 patients were classified into the cognitive dysfunction (CDG) and non-cognitive dysfunction groups (NCDG), respectively. 370, 299 and 58 patients were classified into the “malnourished” (MNG), “at risk of malnutrition” (ARNG) and “well-nourished” (WNG) groups, respectively. A poor cognitive function and poor nutritional status at admission were associated with worse clinical indicators. 276 patients (38.0%) died during the 4 to 5 years of follow-up. The risks of mortality in the ITG, CDG and MNG was 3.88 (hazard ratio; 95% confidence interval: 2.57-5.98), 1.84 (1.28-2.72) and 4.22 (1.76-13.9), respectively. In addition, the cumulative survival rate was 23.6% for the combination of advanced dementia and malnutrition, but 51.0% for moderate dementia and malnutrition. Even undernourishment may improve the prognosis of patients with mild to moderate cognitive impairment.

Conclusion: The early simultaneous measurements of the cognitive function and nutritional status is expected to be useful for predicting the the hospital prognosis, mortality and the effects of early comprehensive nutritional intervention in acute elderly patients with cognitive decline.