The relationship between insomnia and the intensity of drinking in treatment-seeking individuals with alcohol dependence

Background: Although insomnia is highly prevalent in alcohol use disorders(AUD), its associations with the severity of alcohol use, pre-existing psychiatric comorbidities and psychosocial problems are understudied. The present study evaluates the interplay between these factors using a structural equation model (SEM).

Methods: We assessed baseline cross-sectional data on patients with AUD (N = 123) recruited to a placebo-controlled medication trial. Severity of alcohol use was measured by the Brief Michigan Alcoholism Screening Test (B-MAST). Insomnia Severity Index was used to assess insomnia symptoms. The Hamilton scales for Depression and Anxiety, Short Index of Problems and Timeline Follow Back evaluated psychiatric symptoms, psychosocial consequences of drinking and level of alcohol consumption respectively. We used logistic regression to evaluate the association between insomnia and severity of alcohol use while controlling for covariates. We constructed a SEM with observed variables to delineate the effect of psychiatric symptoms, psychosocial factors and current alcohol use on the pathway between alcohol use severity and insomnia.

Results: The sample was predominately male(83.9 %), Black(54.6 %) and employed(60.0 %). About 45 % of the participants reported moderate-severe insomnia.The association between insomnia and B-MAST attenuated after adjustment for demographics, psychiatric symptoms and psychosocial problems(OR[95 % CI] = 1.17(0.99-1.47). SEM findings demonstrated that B-MAST and insomnia were linked to psychiatric symptoms (95 % Asymptotic-Confidence Interval (ACI): 0.015-0.159, p < 0.05) but not to psychosocial problems or current alcohol use.

Conclusion: Among treatment-seeking patients with AUD, psychiatric burden mediated the relationship between severity of alcohol use and insomnia. Clinicians should screen for underlying psychiatric disorders among treatment-seeking patients with AUD complaining of insomnia.