Complete Digital Disconnection as a Prognostic Marker of Mortality or Residential-Care Transition in Older Adults With Cardiovascular Risk: A Nationally Representative Cohort Study.

Background: Routine health care increasingly requires digital access for appointment scheduling, medication refills, test-result review, clinician messaging, remote monitoring, and telehealth. For older adults with cardiovascular-risk conditions, complete internet disconnection may indicate accumulated geriatric vulnerability and barriers to continuous care. We examined whether complete digital disconnection was associated with mortality or residential-care transition and whether the risk gradient was driven by connectivity rather than telehealth use. Methods: We constructed staggered-entry prospective cohorts using rounds 11-14 of the National Health and Aging Trends Study (2021-2025). Community-dwelling Medicare beneficiaries aged ≥65 years with hypertension, heart disease, or diabetes entered the cohort in round 11, 12, or 13 and were followed through round 14. Digital integration was categorized as telehealth use, connected non-use, or complete disconnection. Outcomes were all-cause mortality and a composite of death or transition to nursing-home or residential care. The primary analysis used survey-weighted discrete-time survival models with entry-cohort fixed effects and participant-level cluster-robust variance estimation. Models were sequentially adjusted for demographic, socioeconomic, health, frailty-related, and geriatric-vulnerability factors. Robustness was assessed using multiple imputation, competing-risks models, E-values, and sensitivity analyses addressing reverse causation. Results: Among 12,139 person-baseline observations from 6,530 adults, the survey-weighted prevalence of complete disconnection was 29.7%. Compared with non-disconnected participants, completely disconnected adults had a higher unadjusted risk of the composite outcome; after adjustment for health and frailty-related factors, the association attenuated but persisted (composite hazard ratio [HR], 1.39; 95% CI, 1.12-1.73; mortality HR, 1.50; 95% CI, 1.16-1.94). The survey-weighted 3-year absolute risk difference was 12.1 percentage points. Telehealth users and connected non-users had similar adjusted risks (composite HR, 0.99; 95% CI, 0.79-1.24). Associations weakened after adjustment for functional status and exclusion of first-interval events. Conclusions: Complete digital disconnection was a reproducible and readily measured prognostic marker of mortality or residential-care transition among older adults with cardiovascular-risk conditions. These findings support a prognostic rather than causal interpretation. Age-friendly digital care should preserve offline-accessible pathways for older adults who remain completely disconnected.