Psychiatric comorbidities in patients with major depressive disorder

Psychiatric comorbidities are common in major depressive disorder (MDD). They may worsen outcome and cause economic burden. The primary objective was to examine the prevalence of psychiatric comorbidities in MDD. The secondary objectives were to compare the presence of comorbidities between currently active and past MDD, and between patients with and without suicidal risk.

This was a cross-sectional study. A total of 250 patients with lifetime MDD and age ≥18 years were enrolled. The Mini International Neuropsychiatric Interview (MINI), Thai version, was used to confirm MDD diagnosis and classify comorbidities. MDD diagnosis was confirmed in 190, and 60 patients were excluded due to diagnosis of bipolar disorder.

Of the 190 MDD patients, 25.8% had current MDD and 74.2% had past MDD. Eighty percent were women. The mean age at enrollment was 50 years, and at MDD onset was 41 years. Most patients were married (53.2%), employed (54.8%), and had ≥12 years of education (66.9%). There were 67 patients (35.3%) with one or more psychiatric comorbidities. Comorbidities included dysthymia (19.5%), any anxiety disorders (21.1%) (panic disorder [6.8%], agoraphobia [5.8%], social phobia [3.7%], obsessive-compulsive disorder [OCD] [4.7%], generalized anxiety disorder [5.3%], and post-traumatic stress disorder [4.2%]), alcohol dependence (0.5%), psychotic disorder (1.6%), antisocial personality (1.1%), and eating disorders (0%). Compared with past MDD, the current MDD group had significantly higher OCD (P<0.001), psychotic disorder (P=0.048), past panic disorder (P=0.017), and suicidal risk (P<0.001). Suicidal risk was found in 32.1% of patients. Patients with suicidal risk had more comorbid anxiety disorder of any type (P=0.019) and psychotic disorder (P=0.032).

Several comorbidities were associated with MDD. Patients with active MDD had higher comorbid OCD, psychotic disorder, past panic disorder, and suicidal risk. Patients with suicide risk had higher comorbid anxiety and psychotic disorders.