End-of-life health care use among socially isolated and cognitively impaired older adults.

Background: Social isolation is common in the last years of life, especially among individuals with cognitive impairment (CI), but it is unknown if social isolation is related to end-of-life health care use.

Methods: We used nationally-representative 2006-2018 Health and Retirement Study (HRS) data linked to Medicare claims, including adults age ≥65 interviewed in the last 4 years of life (N = 2380). We used a validated social isolation scale and three social isolation subscales: (1) household contacts (marital status, household size, nearby children), (2) social network interaction (with children, family, and friends), and (3) community engagement. End-of-life health outcomes included 2+ emergency department (ED) visits in the last month of life, hospitalizations or ICU stays in the last 6 months of life, and any hospice use. CI was defined using the validated Langa-Weir methodology. We used logistic regression to test the association of each social isolation measure with each end-of-life outcome, adjusted for sociodemographic covariates, and tested for interaction terms with CI (p < 0.2).

Results: The mean age of our sample of decedents was 81.2 (SD = 9.9), 53% were female, 8% Black, and 4% Hispanic. Overall, social isolation and the community engagement subscale were not associated with end-of-life health care use. Fewer household contacts were associated with lower hospice use (aOR = 0.74, p = 0.005). There were significant interaction terms between the social network interaction subscale and CI for ED use (p = 0.009) and hospitalizations (p = 0.04), and a trend for ICU stays (p = 0.15); individuals with both low social network interaction and CI had lower health care use across all three outcomes compared to other groups.

Conclusions: Individuals with fewer household contacts had lower hospice use, and cognitively impaired individuals with low social network interaction had fewer end-of-life ED visits, hospitalizations, and ICU stays. Clinicians should consider mobilizing external support services to ensure access to goal-concordant care for older adults with limited end-of-life social contact when needed.