866. Estimated ADHD prevalence in a vulnerable at-risk population and effects of CS-treatment on mortality rates in ADHD + severe SUD

Abstract

Abstract Background ADHD is associated with a range of negative psychosocial consequences, including substance use disorder (SUD) and preterm death. Effective pharmacological treatment for ADHD is available, which reduces both ADHD symptomatology and substance use in individuals with concurrent ADHD and SUD. Thus, it appears important 1) to detect individuals with this co-morbidity in vulnerable populations and offer treatment, and 2) to explore whether central stimulant (CS) treatment also influences mortality rates in ADHD patients with SUD. Aims & Objectives This study aimed at 1) to estimate the prevalence of ADHD in an urban homeless Swedish cohort and explore its association with other psychiatric disorders including SUD, and 2) to use registers to explore the association between CS ADHD medication and mortality in individuals with ADHD and severe SUD. Method One hundred homeless individuals were asked to participate and screening instruments were administered (ASRS, WURS, MINI, AUDIT, DUDIT). Medical records were examined for previous ADHD assessments. Scoring positive both on ASRS and WURS was considered indicative of ADHD. The register study included individuals aged 18 and older discharged from addiction compulsory care between July 1st, 2005– December 31st, 2020 (The Swedish National Register of Care for Substance Abuse) and diagnosed with ADHD (ICD-10; the Swedish National Patient Register) at any time up until end of follow up. Prescription of CS ADHD medication was retrieved (the Swedish Prescribed Drugs Register) and patients were linked to the Swedish Cause of Death Register. Mortality rates, stratified by treatment groups (fully treated, intermediate treated or untreated) and sex and adjusted for confounders, were studied. The Cox proportional hazards regression model was used to estimate mortality rate. Results Sixty-five of the homeless individuals consented. Thirty-four % had already received an ADHD diagnosis in high-quality assessments. Of these 16% (three individuals) had ongoing CS treatment. Forty-six % scored positive on ASRS+WURS. 85% had drug problems and 41% were considered drug dependent. There were significant positive associations between ADHD and SUD and between ADHD and anxiety disorders. The registry cohort comprised 1897 individuals. Treated individuals had a 76,5% (95% CI 63,8-84,8; HR=0,24, p <0.0001) lower one-year mortality rate compared to untreated individuals. Multivariate cox proportional hazard regression one-year survival analysis showed that mortality was significantly lower (95% CI 0.148-0.354; HR 0.229; p<0.0001) for treated compared to untreated individuals. Being male increased the 1-year risk of dying with 2,14 (95% CI, 1,28-3,58; HR 2.140; p=0.0038) times compared to being female. Discussion & Conclusions ADHD is likely very prevalent in the homeless Swedish urban population (32-46%) and is associated with SUD and anxiety disorders. Prescription of CS for ADHD is associated with lower mortality rates in adults with ADHD and severe SUD.