(121) Predictors of Retention During and After Residential Treatment for Substance Use Disorders

Background & Introduction: Substance use disorders (SUD) are chronic, relapsing conditions best treated through a chronic disease model of care, emphasizing sustained remission through longitudinal treatment over acute management. Residential treatment for SUD (ASAM Level 3) is a short-term but necessary level of care for patients who do not respond to lower levels of care. There are clear positive outcomes associated with successful residential treatment (de Andrade, Elphinston, Quinn, Allan, & Hides, 2019; Decker, Peglow, Samples, & Cunningham, 2017); however, long-term retention in outpatient treatment offers a greater chance of successful abstinence over shorter term modalities such as residential treatment (Beaulieu, Tremblay, Baudry, Pearson, & Bertrand, 2021). Few studies have examined associations between residential treatment and subsequent retention in outpatient treatment (Harris, McKellar, Moos, Schaefer, & Cronkite, 2006; Rubinsky et al., 2018). This study examined a cohort of patients within a large, multispecialty integrated health care delivery system who were referred to residential treatment to determine what demographic, clinical, and utilization variables were associated with treatment retention. Outcomes included early residential treatment dropout, retention in post-discharge outpatient addiction medicine treatment and a re-referral to residential treatment within 12 months of discharge.

Methods: This was a retrospective, cohort study of adult members of Kaiser Permanente Northern California who were referred for residential SUD treatment over 6.5 years -- (6/1/2016 to 12/31/2022). Electronic health record and claims data were the primary data sources. Exposure measures included demographic and clinical variables: age, sex, race/ethnicity, Neighborhood Depravation Index, primary SUD diagnosis, Charlson Comorbidity Index, and psychiatric comorbidities (anxiety, depression, PTSD, psychotic disorder and personality disorder). Service utilization variables included: referring department (e.g. addiction medicine, emergency department), pre-referral addiction medicine engagement (number of weeks out of 24), and number of emergency department (ED) or hospital admissions in the 12 months preceding the referral date.
Patients who had a residential length of stay (LOS) of less than 5 days were labeled as early treatment dropouts (ETD). Post-discharge outpatient treatment retention (number of weeks out of 24) and occurrence of re-referral were reported by each demographic, clinical, and utilization variable. Chi-squared tests were used to examine associations between all variables and outcomes. Factors that had significant bivariate associations with each outcome of a p-value < 0.10 were included in multivariable models. Odds ratios, 95% confidence intervals, and p-values were reported for each factor.

Results: A total of 4,575 adult patients received referrals to residential treatment during the study period and met inclusion criteria. The final cohort was predominantly male (60%) and White (70%). Most patients had a primary alcohol use disorder (63%), followed by opioid use disorder (14%) and stimulant use disorder (11%). Fourteen percent (N=645) of patients had ETD. Significant risk factors for ETD were: a diagnosis of opioid use disorder vs. alcohol use disorder (OR 1.40, 95% CI=1.10, 1.79), referral from the ED vs. specialty addiction medicine services (OR 2.06, 95% CI=1.44, 2.95), and low engagement prior to referral (0-2 weeks) vs. high engagement (10 or more weeks) (OR 1.61, 95% CI 1.20, 2.13).
Patients who had a LOS >= 5 days were included in post-discharge outcome analyses (N=3930). Post-discharge outpatient treatment retention was categorized into 0-2 weeks (“Minimal”), 3-9 weeks (“Moderate”), and 10+ weeks (“High”). Several demographic factors were associated with lower odds of high treatment retention (compared to minimal retention): age category 18-24 vs. 25-44 years old (OR = 0.35, 95% CI 0.27, 0.46); male (OR=0.71, 95% CI 0.60, 0.84); and Black/African-American vs. White race (OR=0.70, 95% CI 0.49-0.99). A high level of pre-referral engagement (10+ weeks vs. 0-2 weeks) was strongly associated with high retention (OR = 5.71, 95% CI 4.34, 7.52), as was longer LOS in residential treatment. Patients with a residential LOS of 51-80 days had increased odds of high outpatient treatment retention compared to the LOS of 5-25 days group (OR 2.33, 95% CI 1.76, 3.07).
The overall rate of re-referral to residential treatment was 23%. Factors associated with higher odds of re-referral include: age 18-24 vs. 25-44 years old (OR 1.49, 95% CI 1.20, 1.85), diagnoses of anxiety (OR=1.20, 95% CI 1.00, 1.44), or PTSD (OR=1.26, 95%. CI 1.03, 1.55) and those with ≥2 ED or hospital admissions in the prior year (OR = 2.17, 95% CI 1.76, 2.66).

Conclusion & Discussion: This study identified key factors associated with treatment retention during residential treatment and post-discharge outpatient treatment. The strongest associations with treatment retention were seen in patients who had high levels of engagement in outpatient addiction medicine treatment prior to residential, with a lower risk for early dropout and higher likelihood of continuing care. This implies that patients who qualify for outpatient treatment by ASAM criteria should be encouraged to start there rather than being referred directly to residential level of care which many patients perceive as necessary. Higher rates of ETD were observed in referrals made by the ED compared to referrals from addiction medicine specialists; thus, early consultation with addiction medicine is highly recommended for patients in the ED who are seeking treatment, as this may improve resource utilization for scarce residential beds. This study confirmed certain known risks for poor retention including younger age, male gender, and African-American race (Harris et al., 2006). Rates of re-referral to residential, generally considered a negative outcome, were highest in younger patients who were frequent utilizers of hospital services, a finding which should encourage additional efforts at engaging this population in outpatient treatment.

References: Beaulieu, M., Tremblay, J., Baudry, C., Pearson, J., & Bertrand, K. (2021). A systematic review and meta-analysis of the efficacy of the long-term treatment and support of substance use disorders. Soc Sci Med, 285, 114289. doi:10.1016/j.socscimed.2021.114289

de Andrade, D., Elphinston, R. A., Quinn, C., Allan, J., & Hides, L. (2019). The effectiveness of residential treatment services for individuals with substance use disorders: A systematic review. Drug Alcohol Depend, 201, 227-235. doi:10.1016/j.drugalcdep.2019.03.031

Decker, K. P., Peglow, S. L., Samples, C. R., & Cunningham, T. D. (2017). Long-Term Outcomes After Residential Substance Use Treatment: Relapse, Morbidity, and Mortality. Mil Med, 182(1), e1589-e1595. doi:10.7205/MILMED-D-15-00560

Harris, A. H., McKellar, J. D., Moos, R. H., Schaefer, J. A., & Cronkite, R. C. (2006). Predictors of engagement in continuing care following residential substance use disorder treatment. Drug Alcohol Depend, 84(1), 93-101. doi:10.1016/j.drugalcdep.2005.12.010

Rubinsky, A. D., Ellerbe, L. S., Gupta, S., Phelps, T. E., Bowe, T., Burden, J. L., & Harris, A. H. S. (2018). Outpatient continuing care after residential substance use disorder treatment in the US Veterans Health Administration: Facilitators and challenges. Subst Abus, 39(3), 322-330. doi:10.1080/08897077.2017.1391923