Symptom network connectivity in adolescents with comorbid major depressive disorder and social phobia

Major depressive disorder (MDD) and social phobia (SP) are both common and highly co-occurring psychiatric disorders. This study used symptom network analysis approach to examine comorbidity structure and the complex symptom dynamics which may play a role in the co-occurrence of MDD and SP.

Data comes from the National Comorbidity Survey - Adolescent Supplement, a nationally representative survey of adolescents ages 13 to 18 years. This study examined data of adolescents with a lifetime diagnosis of MDD (n = 597), SP (n = 708), and adolescents with comorbid MDD and SP (n = 189). Networks were estimated by means of 26 symptoms from both disorders.

All MDD and SP symptoms were involved in the network of both pure disorders (MDD; SP) and comorbid condition (MDD + SP). Network structure was different between the pure disorders (p = 0.014), but not when comparing each of these disorders that have comorbid condition. Depressive symptoms of poor self-esteem and suicidal symptoms were central (i.e., showed a higher influence) in the symptom network for the pure disorders and for the comorbid condition. Other key symptoms in the comorbid condition network were two depressive symptoms: feelings of worthlessness and anhedonia. SP and MDD networks showed two common key SP symptoms: feeling uncomfortable when meeting new people and feeling uncomfortable talking to people do not know well.

The study of symptom dynamics will provide useful targets for preventing the development of comorbid disorders as well as new lines of intervention to deal with key symptoms of psychiatric disorders.