This prospective cohort study investigates how sleep disturbances affect cognitive recovery and quality of life during early recovery from substance use disorder (SUD). Chronic substance use frequently alters normal sleep architecture, which may impair attention, memory, and everyday functioning. The primary aim is to characterize baseline sleep patterns in adults with SUD compared to healthy control participants and determine whether baseline sleep disruptions predict cognitive and functional recovery over three months of monitored abstinence.
The study includes two groups of participants aged 18 to 45 years: adults diagnosed with a primary substance use disorder undergoing treatment and monitored abstinence, and a comparison group of healthy volunteers matched for age, sex, education, work schedule, and caffeine or nicotine use.
At the beginning of the study, all participants complete:
* Structured diagnostic interviews and clinical assessments for mood, anxiety, and attention.
* Questionnaires evaluating subjective sleep quality (Pittsburgh Sleep Quality Index) and quality of life (WHOQOL-BREF).
* A global cognitive screening test (Montreal Cognitive Assessment) and a computerized attention test (Continuous Performance Task).
* An overnight sleep study (polysomnography) conducted in a sleep laboratory following an initial adaptation night to objectively record brain waves, sleep stages, oxygen levels, and sleep continuity.
Participants in the substance use disorder group undergo supervised abstinence monitoring via periodic clinical check-ins and random urine drug screens. At 1 month and 3 months post-baseline, participants repeat the cognitive tests, quality-of-life questionnaires, and mood/sleep assessments to track recovery trajectories over time (no repeat overnight sleep studies are performed).