Abstract
OBJECTIVES:
After hospitalization, many older adults need post-acute care, including rehabilitation or home care. However, post-acute care expenses can be as high as the costs for the initial hospitalization. Detailed information on monthly post-acute health care expenditures and the characteristics of patients that make up for a large share of these expenditures is scarce. We aimed to calculate costs in acutely hospitalized older patients and identify patient characteristics that are associated with high post-acute care costs.

DESIGN:
Prospective multicenter cohort study (between October 2015 and June 2017).

SETTING AND PARTICIPANTS:
401 acutely hospitalized older persons from internal medicine, cardiology, and geriatric wards.

MEASUREMENTS:
Our primary outcome was mean post-acute care costs within 90 days postdischarge. Post-acute care costs included costs for unplanned readmissions, home care, nursing home care, general practice, and rehabilitation care. Three costs categories were defined: low [0-50th percentile (p0-50)], moderate (p50-75), and high (p75-100). Multinomial logistic regression analyses were conducted to assess the associations between costs and frailty, functional impairment, health-related quality of life, cognitive impairment, and depressive symptoms.

RESULTS:
Costs were distributed unevenly in the population, with the top 10.0% (n = 40) accounting for 52.1% of total post-acute care costs. Mean post-acute care costs were €4035 [standard deviation (SD) 4346] or $4560 (SD 4911). Frailty [odds ratio (OR) 3.44, 95% confidence interval (CI) 1.78-6.63], functional impairment (OR 1.80, 95% CI 1.03-3.16), and poor health-related quality of life (OR 1.89, 95% CI 1.09-3.28) at admission were associated with classification in the high-cost group, compared with the low-cost group.

CONCLUSIONS/IMPLICATIONS:
Post-acute care costs are substantial in a small portion of hospitalized older adults. Frailty, functional impairment, and poor health-related quality of life are associated with higher post-acute care costs and may be used as an indicator of such costs in practice.