Emergent neuropsychiatric symptoms and sleep disorders among older adults in nursing homes who have depressive symptoms and are at risk of dementia: A network analysis

Background: Emergent neuropsychiatric symptoms and sleep disorders are common in older adults with depressive symptoms and may increase the risk of dementia. This study aimed to identify core and bridge symptoms linking emergent neuropsychiatric symptoms and sleep problems, and to compare symptom network structures between subthreshold depression and depression groups. Methods: A cross-sectional study was conducted with 853 older adults residing in nursing homes. Emergent neuropsychiatric symptoms were assessed using the Mild Behavioral Impairment Checklist (MBI-C), and sleep disturbances were measured by the Pittsburgh Sleep Quality Index (PSQI). Network analysis and the Network Comparison Test (NCT) were applied to identify central, bridge, and strongest edge symptoms, and to explore structural differences between groups. Results: In the global network and the depression group, MBI8 (lack of pleasure experience) was the core symptom, and PSQI7 (daytime dysfunction) served as the main bridge symptom. The strongest connection consistently appeared between MBI2 (loss of curiosity in usual interests) and MBI3 (decreased social initiative). In the subthreshold depression group, MBI2 (loss of curiosity in usual interests) became the most central symptom, and the bridge shifted to PSQI4 (habitual sleep efficiency). These results suggest distinct interaction patterns across depression severity levels. Limitations: The cross-sectional design limits causal interpretation. Self-reported measures may introduce bias, and generalizability may be limited to nursing home settings. Conclusions: Identifying central and bridge symptoms may facilitate early detection and targeted interventions for managing emergent neuropsychiatric symptoms and sleep disturbances in older adults with depressive symptoms, potentially lowering dementia risk.