The association of anxiety and depressive disorders with substance use disorders: frequency and relationship with substance use severity

Background Substance use disorders (SUDs) are a common and potentially serious form of mental illness. Common associated mental illnesses include depressive and anxiety disorders. Objectives To examine the frequency of comorbidity and the degree of severity of depressive and anxiety disorders with SUDs in a sample of upper Egyptian patients. Patients and methods A total of 103 patients with SUDs were recruited. There were 95 males and eight females, with an age of 27.5±6.2, and two-thirds (67%) of them came from urban areas. They were subjected to complete substance use history, urine analysis screen for substances of abuse, Hamilton rating scales for anxiety and depression, and the Addiction Severity Index (ASI). Results Overall, 41 (39.8%) patients began using substances before the age of 18 years, and 79 (76.7%) patients used more than one substance. Moreover, 74 (71.9%) patients had moderate or severe anxiety, whereas 78 (75.7%) patients had moderate or severe depression. Anxiety scores were positively and significantly correlated with three of the seven domains of ASI in addition to the duration of substance use, whereas depression scores were positively and significantly correlated with six of the ASI domains. Patients using polysubstances scored significantly higher than those using a single substance on anxiety and depressive scores. Conclusions Anxiety and depressive disorders are frequently diagnosed in patients with SUDs. Increased severity of both types of disorders is associated with increased parameters of substance use severity. Using more than one substance increases the likelihood of having more severe anxiety and depressive illness.