Introduction: A bidirectional relation between substance use and insomnia has been described, although there are few studies examining insomnia in the population of people with addiction. The aim of this study was to describe the prevalence of insomnia during active substance use in patients with addiction and its associated clinical features.
Patients and methods: Descriptive study in patients diagnosed with substance dependence disorder admitted to a Hospital Detoxification Unit. The existence of insomnia prior to admission was assessed using the Oviedo Sleep Questionnaire (OSQ). Demographic variables, consumptionrelated clinical variables, and diagnostic variables were collected and the SCID-I and -II (Structured Clinical Interview for DSM-IV) and CAADID (Conners’ Adult ADHD Diagnostic Interview for DSM-IV) were administered to evaluate the psychiatric diagnoses. Bivariate and multivariate analyses were made of the data.
Results: 481 patients (72.6% men, age 40.6±10.1 years) were enrolled. 64.3% of the patients reported insomnia during active substance use. The most common type of insomnia was fragmented nocturnal sleep (49.9%). The factors significantly associated with insomnia were polysubstance drug use, medical comorbidities (most notably, infectious diseases), anxiety disorder, personality disorder (particularly cluster C), a greater number of previous admissions for detoxication, and early age at onset of substance use.
Conclusions: Insomnia is highly prevalent in patients with addiction during active use of the substance. Fragmented nocturnal sleep was the most common type of insomnia. Patients with addiction and comorbid anxiety disorder, medical comorbidity, and early onset of dependence were more likely to experience insomnia.