Psychic anxiety and sleep components in major depression: a symptom network analysis of comorbid symptoms

Sleep disturbance and anxiety are common in major depressive disorder (MDD), but their symptom-level associations remain incompletely characterized. We used symptom network analysis to examine how depressive symptoms, anxiety symptoms, and sleep components cluster and connect in an outpatient MDD sample. We analyzed cross-sectional data from 450 outpatients with MDD recruited at ShuiKuang Hospital, Liupanshui, China, between January 2020 and December 2023. Depressive symptoms were assessed with the Hamilton Depression Rating Scale (HAM-D), anxiety symptoms with the Self-Rating Anxiety Scale (SAS), and sleep with the Pittsburgh Sleep Quality Index (PSQI). The primary network was estimated by averaging Spearman correlation matrices across 20 multiple-imputation datasets and applying EBICglasso (gamma = 0.5). We computed node strength and bridge strength and treated both as descriptive network properties rather than causal or interventional indices. Sensitivity analyses included complete-case estimation, a HAM-D > = 14 subgroup, an overlap-pruned network, a PSQI-global-score network, a redundancy check, and an ordinal sensitivity analysis based on cor_auto. The primary network was highly sparse, with 41 nodes but only 20 non-zero edges (density 2.44%); 26 nodes were completely isolated. Psychic anxiety (HAM-D item 10) showed the highest strength and bridge strength. Four PSQI components occupied the remaining top-5 strength positions: subjective sleep quality, sleep disturbances, daytime dysfunction, and sleep latency. Rank ordering was stable across imputations (median Spearman rho for strength = 0.931; bridge = 0.956), complete-case analysis, the HAM-D > = 14 subgroup, and the overlap-pruned network. Goldbricker identified no suggested node reductions. However, when the seven PSQI components were collapsed into a single global PSQI node, sleep prominence attenuated markedly, indicating that component-level granularity contributed to the apparent centrality of sleep. In this sparse cross-sectional MDD network, psychic anxiety and several PSQI components were statistically prominent nodes, but the large number of isolated symptoms and the sensitivity of sleep findings to PSQI granularity require cautious interpretation. These results support careful assessment of anxiety and sleep in MDD, but they do not establish causal drivers or treatment targets. Not applicable.