Unravelling symptom interplay of depression, anxiety, insomnia and suicidality in adolescents: A network analysis

Depression, anxiety, and insomnia have been identified as risk factors for suicidality. However, limited research has explored the interplay among these mental health problems at a symptom level and how they relate to suicidality, especially in adolescents - a group undergoing substantial developmental changes, such as intrinsic circadian delay. This study aimed to examine the symptom networks of depression, anxiety, and insomnia in relation to suicidality and chronotype, and to identify potential bridge symptoms linking these symptom clusters.

A total of 3037 adolescents (Mean age = 14.56 ± 1.77; 35.40 % male) were recruited. Symptoms of depression, anxiety, and insomnia were assessed using the Patient Health Questionnaire-9 (PHQ-9), General Anxiety Disorder-7 (GAD-7) and Insomnia Severity Index (ISI). Network estimation methods were employed to identify central and bridge symptoms and to compare the network models across gender and chronotype groups.

The prevalence of probable depression (PHQ-9 ≥ 10), anxiety (GAD-7 ≥ 10), and insomnia (ISI ≥ 9) was 32.6 %, 23.1 %, and 30.5 %, respectively. About 27.7 % of adolescents reported suicidality within the past two weeks. Within the network, difficulty maintaining sleep emerged as the most influential node, followed by uncontrollable worry, distress caused by sleep disturbances, trouble relaxing, and sad mood. Additionally, sad mood, sleep disturbances, fatigue, and guilt from the depression cluster, and uncontrollable worry from the anxiety cluster were identified as the strongest bridge symptoms in the network. The symptom networks did not differ in global edge strength and network structure across genders and chronotypes (ps > 0.10). Notably, all identified bridge symptoms, except fatigue, were directly linked to suicidality.

Our findings highlighted the potential transdiagnostic significance of sad mood, sleep disturbances, fatigue, guilt, and uncontrollable worry in the development and maintenance of the comorbidity of depression, anxiety, insomnia, and suicidality in adolescents. Targeting these symptoms may inform more effective intervention strategies to manage psychopathology and reduce suicidality in this population.