Dementia and End-of-Life Shared Decision-Making Among Older US Adults

To examine whether dementia is associated with differences in advance directive completion, decision-making needs near death, surrogate involvement, and concordance between expressed preferences for care and care received among older US adults.

Retrospective, nationally representative observational study using Health and Retirement Study Exit Interview data from 2010 to 2022.

The study included 5,389 decedents aged 50 years or older with complete information on dementia status, end-of-life decision-making outcomes, and selected covariates, representing approximately 22.2 million US decedents. Of these, 1,010 (weighted 17.7%) had dementia prior to death.

Dementia status was identified from proxy reports of Alzheimer's disease or another form of dementia before death. Primary outcomes were advance directive completion and the occurrence of important medical decisions during the final days of life. Secondary outcomes included the decedent's ability to participate in decision-making, the primary decision-maker, and concordance between preferences for comfort-focused care and care received. Analyses incorporated Health and Retirement Study sampling weights, strata, and primary sampling units. Survey-weighted descriptive analyses and modified Poisson regression with robust variance estimation were used to compare decedents with and without dementia and estimate adjusted risk ratios (aRRs) and 95% CIs.

Decedents with dementia were more likely than those without dementia to have completed an advance directive (81.3% vs 69.1%; P < .001; aRR, 1.11; 95% CI, 1.07-1.15) and to have important medical decisions requiring resolution during the final days of life (54.3% vs 47.2%; P < .001; aRR, 1.09; 95% CI, 1.01-1.19). They were also substantially more likely to be unable to participate in end-of-life medical decision-making (78.9% vs 48.0%; P < .001), with children or grandchildren more frequently serving as the primary decision-makers (63.9% vs 45.6%; P < .001). Among decedents with documented advance directives, preferences for and receipt of comfort-focused care were high in both groups, with no significant differences by dementia status.

Decedents with dementia experienced a distinct end-of-life shared decision-making pattern characterized not only by greater advance care planning but also greater decisional needs and reliance on surrogate decision-makers. These findings suggest that advance directives should be viewed as one component of an ongoing shared decision-making process rather than a substitute for it. Health care systems should complement advance care planning with early and ongoing caregiver engagement, structured decision support, and integration of palliative care across the dementia trajectory to help patients and families navigate evolving end-of-life decisions.