The Mediating Effect of Physiological Health Fear Between Depressive Mood and Sleep Quality in Elderly Parkinson's Disease Patients.

OBJECTIVE: To investigate the relationship between depressive mood and sleep quality in elderly patients with Parkinson's disease (PD), and to analyze the mediating role of fear of progression (FoP). METHODS: Between June 2024 and April 2025, 234 elderly patients with PD attending the Affiliated Hospital of Nantong University were enrolled. Participants completed the General Demographic Questionnaire, the 15-item Geriatric Depression Scale (GDS-15), the Fear of Progression Questionnaire Short Form (FoP-Q-SF), and the Parkinson's Disease Sleep Scale (PDSS). Spearman's rank correlation analysis was used to assess associations among variables. Mediation analyses were conducted using the PROCESS macro (version 4.0) in SPSS. RESULTS: Sleep quality [median (IQR): 104 (84-130)] was significantly negatively correlated with depressive mood [7 (3-11)], total FoP [35 (30-40)], and the physiological health fear subscale [19 (17-22)] (r = -0.434, -0.318, -0.419, respectively; all p < 0.01), as well as with the social-family fear subscale [16 (14-18)] (r = -0.168, p < 0.05). Depressive mood was positively correlated with total FoP, physiological health fear, and social-family fear (r = 0.632, 0.675, 0.481, respectively; all p < 0.01). Mediation analysis revealed that depressive mood had a significant direct effect on sleep quality (β = -1.772, 95% CI: -2.839 to -0.706). Furthermore, the physiological health fear dimension of FoP partially mediated the relationship between depressive mood and sleep quality (indirect effect β = -1.010, 95% CI: -1.723 to -0.314). CONCLUSION: In elderly patients with PD, depressive mood directly impairs sleep quality and also exerts an indirect negative effect via fear related to physiological health deterioration. Targeting both depression and FoP, particularly physiological health concerns may improve sleep outcomes in this population.