Study Objectives To develop and initially validate the Circadian Disruption Index (CDI), a self-report measure of circadian disruption, and obtain preliminary evidence of its responsiveness to circadian health education. Methods In Study 1, 244 participants completed a 22-item CDI version and external measures. The sample was randomly divided for exploratory and confirmatory factor analyses. Internal consistency, external associations, and discrimination of poor sleep quality were examined. In Study 2, 72 postgraduate students completed the CDI before and 1 week after a 16-hour circadian health education program in an uncontrolled pre-post design. Results Analyses yielded a 15-item, three-factor structure comprising rhythm stability and light exposure, behavioral habits and diet, and sleep quality and subjective complaints. Total-score internal consistency was acceptable (Cronbach's = 0.871). Confirmatory factor analysis showed a comparative fit index of 0.902 and a root mean square error of approximation of 0.072, although the Tucker-Lewis index was 0.882. CDI scores correlated with sleep quality, chronotype, corrected midsleep on free days, depression, and anxiety, but not social jetlag. The area under the curve for poor sleep quality was 0.807 (95% confidence interval, 0.753-0.862), with an exploratory cutoff of [≤] 23. In Study 2, CDI scores decreased from 22.26 to 19.88 (p = 0.002; Cohen's dz = 0.36). Conclusions The CDI demonstrated satisfactory internal consistency, a meaningful multidimensional structure, and responsiveness to short-term changes following circadian health education, supporting its potential utility for assessing circadian disruption and monitoring circadian-related behavioral changes.
Y. Fan, M. Tian, J. Xu et al.· medRxiv· 0 citations
Parkinson's disease (PD) is a progressive neurodegenerative disorder commonly accompanied by cognitive decline, yet the mechanisms linking disrupted brain homeostasis to progressive cognitive impairment remain unclear. Emerging evidence suggests that the choroid plexus (ChP) and the locus coeruleus (LC) are involved in cerebrospinal fluid dynamics and norepinephrine regulation, respectively, but their longitudinal alterations and interrelationships in PD have not been systematically examined. We conducted a two-year longitudinal study including 90 PD patients and 51 healthy controls (HCs) undergoing multimodal MRI. ChP volume (ChP-V) was derived from T1-weighted structural imaging, ChP blood flow (ChP-BF) was assessed using pseudo-continuous arterial spin labeling, and LC integrity was ascertained with the contrast-to-noise ratio of the LC (LC-CNR) in neuromelanin-sensitive MRI. Group differences, longitudinal alterations, and associations with neuropsychological performance were examined. Over two years, PD patients showed progressive increases in ChP-V (F = 12.45, p < 0.001), reductions in ChP-BF (F = 18.98, p < 0.001), and declines in LC-CNR (F = 16.80, p < 0.001). Baseline LC-CNR was already reduced in PD compared with HCs (t = 3.023, p = 0.003). The longitudinal changes were more pronounced in male patients. ChP-BF was positively correlated with LC-CNR at baseline (r = 0.293, p = 0.006). Moreover, reductions in ChP-BF and LC-CNR were associated with worsening cognitive performance. While LC dysfunction was evident early in the disease course, progressive ChP alterations, particularly in ChP perfusion, provided additional information on longitudinal disease progression, supporting their combined value and highlighting the importance of gender-specific longitudinal monitoring.
H. Li, J. Jia, J. Wang et al.· medRxiv· 0 citations