Association of Psychiatric Diagnoses and Medicaid Coverage with Length of Stay Among Inpatients Discharged to Skilled Nursing Facilities

Abstract

Background: Inpatients with psychiatric diagnoses often require higher levels of care in skilled nursing facilities (SNFs) and are more likely to be covered by Medicaid, which reimburses SNFs at significantly lower rates than Medicare and commercial payors.

Objective: To characterize factors affecting length of stay in inpatients discharged to SNFs.

Design: A retrospective cross-sectional study design using 2016-2018 data from National Inpatient Sample.

Participants: Inpatients aged ≥ 40 who were discharged to SNFs.

Exposures: Primary discharge diagnosis (medical, psychiatric, or substance use) and primary payor.

Main outcomes and measures: Length of stay, categorized non-exclusively as >3 days, >7 days, or > 14 days.

Results: Among 9,821,155 inpatient discharges to SNFs between 2016 and 2018, 95.7% had medical primary discharge diagnoses, 3.3% psychiatric diagnoses, and 1.0% substance use diagnoses; Medicare was the most common primary payor (83.3%), followed by private insurance (7.9%), Medicaid (6.6%), and others (2.2%). Median length of stay for all patients was 5.0 days (interquartile range [IQR], 3.0-8.0), 5.0 (IQR, 3.0-8.0) for those with medical diagnoses, 8.0 (IQR, 4.0-15.0) for psychiatric diagnoses, and 5.0 (IQR, 3.0-8.0) for substance use diagnoses. After multivariable adjustment, compared to patients with medical diagnoses, patients with psychiatric diagnoses were more likely to have hospital stays > 3, > 7, and > 14 days, respectively (p < 0.001). Compared to Medicare patients, Medicaid patients were more likely to have hospital stays > 3, > 7, and > 14 days, respectively (p < 0.001). Compared to patients with medical diagnoses, those with psychiatric diagnoses were also more likely to have lengths of stay 1 times, 1.5 times, and 2 times greater than the national geometric mean length of stay for that diagnosis-related group (p < 0.001).

Conclusions: Patients discharged to SNFs after inpatient hospitalization for psychiatric diagnoses and with Medicaid coverage were more likely to have longer lengths of stay than patients with medical diagnoses and those with Medicare coverage, respectively.