Relationship between mortality and vitality in patients with mild cognitive impairment/dementia: An 8-year retrospective study.

Abstract

The study aimed to investigate the association of vitality, as measured using the vitality index (Vix), with the survival outcomes of older adults with mild cognitive impairment (MCI) or dementia. We analyzed data from 3731 patients in the National Center for Geriatrics and Gerontology - Life Stories of Individuals with Dementia cohort from July 2010 to September 2018. The main focus was to correlate Vix scores with the time from the initial visit to death. Vix was categorized into "moderately to severely impaired" (0-7 points), "mildly impaired" (8-9 points), and "normal" (10 points) groups. Survival outcomes were assessed using a Cox proportional hazards model, adjusted for various factors. We conducted a mediation analysis to evaluate the effect of body mass index (BMI), instrumental activities of daily living (IADL), and basic activities of daily living (BADL) on the association between vitality and mortality. Stratified analysis was also conducted for the Mini-Mental State Examination groups. We included 2740 patients with an average follow-up of 1315 days. The mortality rate was 15.7%. The Vix distribution was 16% at 0-7 points; 40%, 8-9 points; and 44%, 10 points. Patients in the "moderately to severely impaired" category, characterized by lower Vix scores, exhibited notably higher mortality rates. Mediation effects emphasized the significant roles of BMI, IADL, and BADL in influencing survival outcomes. Vitality significantly influences patient survival rates. The association between vitality and mortality seems to be mediated by IADL and BADL, which has significant clinical implications. Geriatr Gerontol Int 2024; 24: 221-228.