Survival and cognitive deterioration in elderly patients undergoing hemodialysis

Abstract

This study aimed to elucidate the 5-year changes in the cognitive function of elderly patients undergoing hemodialysis and its association with survival and related factors. Cognitive function in patients aged ≥65 years undergoing hemodialysis at the Nagasaki Renal Center was assessed using the Mini-Mental State Examination (MMSE) in 2016. Patients were subsequently classified into normal, mild cognitive impairment (MCI) and suspected dementia groups according to their scores; MMSE was conducted at 30 and 60months thereafter. The patients were followed until 2021. The association between survival and patient backgrounds was analyzed. Of the 181 patients, 168 completed follow-up and were classified into normal (n=71, 42.3%), MCI (n=44, 26.1%), and suspected dementia (n=53, 31.5%) groups. Multivariable logistic regression analysis showed that age, female sex, and geriatric nutritional risk index were associated with MMSE scores <24. The 5-year survival rates were 60.6%, 40.9%, and 22.6% in the normal, MCI and suspected dementia groups, respectively. With some exceptions, MMSE results tended to decline during the observation period. A multivariate Cox proportional hazards model showed that age (hazard ratio [HR], 1.04; P=0.007), dialysis vintage (HR, 0.96; P=0.04), male sex (HR, 1.77; P=0.02), geriatric nutritional risk index (HR, 0.94; P < 0.001) and MMSE score (HR, 0.96; P=0.01) were independent risk factors for patient survival. Cognitive impairment in patients undergoing hemodialysis was associated with age and nutritional status. Patients with cognitive impairment had a poor prognosis. Geriatr Gerontol Int 2023; 23: 111-116.