Abstract
BACKGROUND: This study is original in that it identified the care trajectories of patients with substance-related disorders (SRDs) over a 9-year period, and associated these trajectories with the patients' sociodemographic and clinical characteristics, quality of care received, and subsequent adverse outcomes (high emergency department use, repeated hospitalizations, suicidal behaviors, death). METHODS: Health administrative databases from Quebec, Canada (1996-2022) were used to investigate a cohort of 4075 patients with SRDs. Group-based multi-trajectory modeling was produced to identify profiles of care trajectories from April 1st 2012 to March 31st 2021. Multinomial regressions and survival analysis were conducted to associate profiles to patient characteristics, and adverse outcomes over the following year. RESULTS: Five profiles of care trajectories were identified: "Low overall but increasing care use" (Profile 1, 30% of sample); "High, increasing outpatient physical health care use" (Profile 2, 26%); "High, increasing outpatient SRD care use" (Profile 3, 15%); "High overall care use" (Profile 4, 14%); and "Increasing but moderate outpatient care use" (Profile 5, 15%). Profiles 3 and 4 used substantially more SRD outpatient care. Patients in Profiles 4 and 5 had more complex health conditions and engaged in more varied, sustained care over time, but subsequently experienced the worst adverse outcomes. In contrast, Profile 1 patients had better overall health conditions, followed by Profile 2 (older at SRD onset, less materially deprived) and 3 (more SRD issues), which both exhibited higher continuity of care than Profile 1. Profile 3 had the lowest rate of treatment dropouts. CONCLUSION: Use of care and adverse outcomes were strongly linked to the patients' clinical conditions. Tailored interventions may be recommended for each profile: outreach and motivational interventions for Profile 1; applying the chronic care model for Profile 2; high continuity of physician and SRD care for Profile 3; assertive community treatment for Profile 4; and intensive case management for Profile 5. To better address the unmet needs of patients with SRDs, overall outpatient services may be substantially consolidated and improved. Acute care providers and general practitioners may also play a key role in identifying patients with SRDs and referring them to appropriate outpatient services.