(PS2-D96) Polypharmacy Risk Profile for Psychiatric Inpatients with Major Depressive Disorder and Co-occurring Substance Use Disorders

Background: Among psychiatric inpatient populations, rates of Major Depressive Disorder (MDD) are high, with estimates showing that MDD accounts for 28% of admissions to psychiatric hospital settings. Inpatients frequently present with comorbid conditions, including substance use disorders (SUDs; up to 50%). Polypharmacy (i.e., being prescribed 3 or more medications) may be relatively common in dual diagnosis patients. While co-prescription of drugs with differing mechanisms of action may be beneficial in psychiatric treatment in some circumstances, polypharmacy also lends itself to increased toxicity, decreased treatment adherence and compliance, and may directly and indirectly contribute to suicide rates in the form of intentional and unintentional drug overdose This study sought to examine prevalence and risk factors associated with psychotropic polypharmacy in hospitalized patients with MDD and co-occurring SUDs.

Methods: An electronic chart review was conducted with N = 1,315 individuals admitted to a psychiatric hospital; n = 505 (38.4%) were identified as having co-occurring MDD+SUD. We examined psychotropic polypharmacy and clinical severity to explore the risk for concerning drug interactions.

Results: Overall, 12.1% (n = 61) of patients were prescribed 1 psychotropic medication, 53% (n = 268) were prescribed 2 or more total psychotropic medications, and 32% (n = 162) reported 3 or more psychotropic medications. Potentially dangerous polypharmacy patterns were identified among those with MDD+SUD and were related to negative clinical outcomes, particularly in terms of risk of oversedation for individuals with an Opioid Use Disorder (OUD). Patients receiving a co-prescription of 3 or more psychotropic medications demonstrated higher depressive severity, increased likelihood of reporting a previous psychiatric hospitalization, higher rates of subsequent re-hospitalization, and lower overall functioning when compared to patients with single or dual prescriptions. Groups at the highest risk for polypharmacy included patients who were female, older in age, lower functioning, and presenting with a co-occurring OUD. Having an OUD was associated with particularly high risk of polypharmacy, while having a Cannabis Use Disorder was associated with the lowest polypharmacy.

Conclusions: Results highlight a high prevalence of polypharmacy among patients with comorbid SUDs and an elevated risk for negative outcomes, as well as the potential dangers of drug-drug interactions due to the effect of one substance on the body’s ability to metabolize the other. While medications in isolation may be viewed as safe, in combination, they may negatively impact functioning and result in poor treatment outcomes. There is a continued need to improve identification of complex patient presentations and adjust medications in a hospital setting to improve treatment outcomes and reduce mortality.