Substance Use Disorders in Patients With Parkinson's Disease and Adverse Hospitalization Outcomes: A National Inpatient Study.

Objectives To understand the demographic pattern of substance use disorders (SUD) in Parkinson's disease (PD) inpatients and to evaluate the impact of SUD on hospitalization outcomes including the severity of illness, length of stay (LOS), total charges, and disposition to nursing facilities. Methods We used the nationwide inpatient sample and identified adult patients (age, ≥40 years) with PD as a primary diagnosis and comorbid SUD (N = 959) and grouped by co-diagnosis of alcohol (N = 789), cannabis (N = 46), opioid (N = 30), stimulants (N = 54) and barbiturate (N = 40) use disorders. We used a binomial logistic regression model to evaluate the odds ratio (OR) for major loss of functioning and disposition to nursing facilities in PD inpatients. All regression models were adjusted for demographics, including age, sex, race, and median household income. Results Alcohol, opioid, and stimulant use disorders were prevalent in old-age adults (60-79 years), males, and whites, but cannabis use was prevalent in middle-aged adults (40-59 years), and barbiturate use among older-age (>80 years). The severity of illness is statistically higher in PD inpatients with comorbid opioid and barbiturate use disorders with major loss of body functioning, closely seconded by alcohol and stimulant use disorder cohorts (27.6% and 25.9%, respectively). Disease severity and loss of body functioning increase with advancing age (>80 years adults, OR 5.8, 95%CI 5.32-6.37), and in blacks (OR 1.7, 95%CI 1.56-1.81), and those with opioid use disorder (OR 3.8, 95%CI 1.96-7.35). PD inpatients with barbiturate use disorder had a higher LOS and charges by 17.4 days and $68,922, and six-fold increased likelihood (95%CI 2.33-15.67) for disposition to nursing facilities. Conclusions SUD is prevalent among PD patients and is associated with more severe illnesses with body loss functioning and prolonged care. A multidisciplinary care model including collaborative neuropsychiatric and addiction management is required to manage SUD among PD patients to lessen disease severity, slow down the disease progression and potentially save medical costs.