Levels of mental distress over 18 years after entering treatment for substance use disorders: A longitudinal cohort study

Abstract

Aims: The aims were to investigate whether baseline characteristics and problematic substance use were related to change in mental distress over time in patients with substance use disorders during an 18-year period. Method: This was a prospective, longitudinal study of patients followed for 18 years after entering specialised treatment for substance use disorders. A sample of 291 patients was recruited in 1997 and 1998. Mental distress was measured using the Hopkins Symptom Checklist 25 at baseline, and at six and 18 years. Lifetime psychiatric disorders and substance use disorders at baseline were measured using the Composite International Diagnostic Interview, while personality disorders were measured using the Millon Clinical Multiaxial Inventory II. At the six- and 18-year follow-ups, substance use was measured using the Alcohol Use Disorders Identification Test and the Drug Use Disorders Identification Test. Linear mixed model was estimated to assess the overall level of mental distress over 18 years for participants with complete data at baseline ( n = 232). Results: In an adjusted model, problematic substance use assessed simultaneously with mental distress, having lifetime affective, anxiety and personality disorder at baseline were associated with greater levels of mental distress over the 18-year period. The change in mental distress from baseline to the six-year, but not to the 18-year, follow-up was significantly larger among females than among males. Conclusion: The results suggests a reciprocal relationship over time between substance use and mental health problems. Also, there seems to be an additive effect between ongoing problematic substance use and lifetime mental disorders on greater levels of mental distress. This addresses the importance of integrated treatment for both substance use disorders and mental disorders to improve the long-term course for patients with these comorbid disorders.

Inpatients in substance use treatment with co-occurring psychiatric disorders: a prospective cohort study of characteristics and relapse predictors

“…In line with prior research including SUD inpatient treatment samples [12,13,17] patients with COD had indications of persistently poorer psychological functioning in terms of higher levels of mental distress, as compared to patients without COD. This finding underscores the need for SUD treatment providers to attend to mental health problems among patients with COD, and also alludes to the importance of available and accessible community mental health services upon discharge from the inpatient stay.…”

“…Studies investigating psychological characteristics among patients with and without COD consistently showed that those with COD reported higher levels of general mental distress, [12][13][14]17]. Anxiety and depression are the two most frequently co-occurring psychiatric disorders among SUD patients [16].…”

“…The combination of substance use and psychiatric disorders may complicate shift in substance use behavior [10] and worsen treatment prognosis [11]. This combination is also associated with more severe features, such as more severe psychiatric symptoms, substance use, and relapse [12][13][14][15]. Despite this, little is known regarding the demographic, psychological and clinical characteristics (e.g.…”

Cognitive impairment as a predictor of long-term psychological distress in patients with polysubstance use disorders: a prospective longitudinal cohort study

“…The study’s results align with prior clinical and population-based research on the prevalence and developmental trajectories of mental illness, affirming that mental health problems among patients with SUD are substantial and that mental health problems act as a risk factor for later life mental health problems [ 15 , 17 , 123 – 125 ]. It is also noted that in accordance with the recommended cut-off scores from SCL-90-R [ 76 ], a substantial proportion (76%) of the participants reported a level of psychological distress at treatment initiation that warrants further assessment.…”

“…This suggest that a two-step screening-diagnostic assessment procedure may be redundant for patients with pSUD and that a comprehensive diagnostic assessment of mental illness could represent a more cost-efficient approach in treatment planning for all patients with pSUD. Unsurprisingly, the study reinforces the well-documented association between substance intake and greater levels of psychological distress [ 15 , 17 , 130 ].…”