BACKGROUND: Polypharmacy is associated with adverse outcomes, particularly in older multimorbid adults. However, little is known about the negative outcomes associated with multiple central nervous system (CNS)-active medications that are commonly prescribed to these patients.

OBJECTIVE: To assess the association between the number of CNS-active medications at discharge and the risk of 1-year all-cause hospital readmission, drug-related hospital readmission (DRA), death, quality of life (QoL) and functional status in older multimorbid adults.

METHODS: Among 2008 older multimorbid inpatients with polypharmacy, we assessed the association between the number of CNS-active medications and 1-year all-cause hospital readmission, DRA, and death by Cox proportional hazard models. We further assessed the association of the number of CNS-active medications with QoL (measured with EQ-5D-VAS) and functional status (measured with Barthel Index) using binary and quantile regression models. Analyses were adjusted for age, sex, discharge location, Charlson Comorbidity Index, depression/anxiety, and randomization arm. Additional sensitivity analyses were adjusted for the number of non-CNS active medications, neurological and psychiatric comorbidities, alcohol or tobacco use, education level, and living arrangements.

RESULTS: The risk of all-cause hospital readmission and DRA increased by 7% with each additional CNS-active medication (multivariable-adjusted hazard ratio (HR) 1.07 (95% confidence interval 1.03 to 1.12) for all-cause hospital readmission and 1.07 (1.01 to 1.14) for DRA). HR for death was 1.14 (1.07 to 1.23) for each additional CNS-active medication. The mean differences in EQ-5D-VAS and Barthel Index after 1 year were -2.13 (-2.82 to -1.44) and -1.6 (-2.16 to -1.04) respectively, per additional CNS-active medication.

CONCLUSION: The presence of CNS-active medications at discharge is associated with a higher risk for 1-year all-cause hospital readmission and DRA in older multimorbid adults with polypharmacy. Additionally, CNS-active medications were associated with lower QoL and functional status.

TRAIL REGISTRATION

ClinicalTrials.gov NCT02986425.