Anxiety and depressive symptoms among students in higher vocational colleges: application of latent profile analysis and network analysis

Abstract Background Depression and anxiety commonly co-occur among students in higher vocational colleges. However, most previous studies have treated this population as homogeneous, overlooking the heterogeneity of anxiety-depression comorbidity. Consequently, the symptom interaction patterns across distinct subgroups remain poorly understood. This study aims to identify potential subgroups of anxiety-depression comorbidity among vocational college students, explore the core and bridging symptoms within the symptom networks that sustain these conditions in each subgroup, and compare differences in network structures across the subgroups. Methods A cross-sectional survey was conducted among 7,932 students from higher vocational colleges in Wenjiang District, Chengdu, China, between January and February 2022 using stratified random sampling. Anxiety and depressive symptoms were assessed using the Generalized Anxiety Disorder-7 (GAD-7) and the Patient Health Questionnaire-9 (PHQ-9). Latent Profile Analysis (LPA) was performed to identify heterogeneous subgroups of anxiety–depression comorbidity. Symptom networks were constructed for each subgroup, and Expected Influence (EI) and Bridge Expected Influence (BEI) were estimated to identify core and bridge symptoms. Network Comparison Tests (NCTs) were conducted to compare network structure and global strength across subgroups. Results LPA classified the study participants into three subgroups: the low comorbidity group (68.3%), the moderate comorbidity group (24.7%), and the high comorbidity group (7.0%). The most central bridging symptom in the low comorbidity group was PHQ6 (low self-esteem), while in both the moderate comorbidity and high comorbidity groups, GAD5 (restlessness) was the most prominent bridging symptom. Global strength differed significantly across all pairwise profile comparisons in the unadjusted analyses; however, these differences were no longer statistically significant after covariate adjustment. No significant differences in overall network structure were detected. Conclusion Developing personalized intervention plans targeting subgroup-specific bridging symptoms may improve the prognosis of comorbid depression and anxiety among vocational college students.