Latent Growth Mediation Model In Activities Of Daily Living In Patients With Parkinson’s Disease

Objective:This aim of the study was to explore the change trajectories of excessive daytime sleepiness,depression,autonomic dysfunction,and activities of daily living in patients with Parkinson’s disease,and to analyze the longitudinal mediating effects of depression and autonomic dysfunction between excessive daytime sleepiness and activities of daily living.Methods:The subjects of this study were 410 patients with Parkinson’s disease in the Parkinson’s Progression Markers Initiative（PPMI）database with a follow-up period of 6 year.Patients’excessive daytime sleepiness were evaluated using Epworth sleepiness scale（ESS）.The 15-item geriatric depression scale（GDS-15）was used to evaluate depression of patients.The scales for outcomes in Parkinson’s disease-autonomic（SCOPA-AUT）was used to evaluate autonomic dysfunction of patients.The activities of daily living were evaluated using unified Parkinson’s disease rating scale（UPDRSⅡ）.Using the activities of daily living as the independent variable,excessive daytime sleepiness as the dependent variable,the autonomic dysfunction and depression as the mediating variable,the latent growth mediation model was constructed.The full information maximum likelihood was used to evaluate parameters of the model,and the mediated effects were tested by biased Bootstrap method.Results:Pearson correlation analysis showed that excessive daytime sleepiness,depression and activities of daily living were positively correlated with each other（P<0.05）,and excessive daytime sleepiness,autonomic dysfunction and activities of daily living were positively correlated with each other（P<0.05）.The results of univariate latent growth model showed that the degree of daytime excessive sleepiness,depression and autonomic dysfunction increased while the degree of activities of daily living gradually decreased.The intercept and slope of all the main variables in the study have significant distribution（P<0.001）,which confirmed the individual differences of time change.The results of multivariate latent growth mediation model showed that the indirect effect of intercept of excessive daytime sleepiness through the intercept of depression on the intercept of activities of daily living was statistically significant（?₁?₅=0.061,95%CI:0.017～0.132）,and direct effect of intercept of excessive daytime sleepiness on the intercept of activities of daily living was statistically significant（?₃=0.355,95%CI:0.243～0.469）;therefore,the intercept of depression had a partial mediating effect.The indirect effect of slope of excessive daytime sleepiness through the slope of depression on the slope of activities of daily living was statistically significant（ab=0.154,95%CI:0.054～0.309）,and direct effect of slope of excessive daytime sleepiness on the slope of activities of daily living was statistically significant（c’=0.357,95%CI:0.111～0.587）;therefore,the slope of depression had a partial mediating effect.In summary,depression acted a mediator between the intercept and the slope,thereby confirming the existence of a longitudinal mediation effect.At the same time,the indirect effect of intercept of excessive daytime sleepiness through the intercept of autonomic dysfunction on the intercept of activities of daily living was statistically significant（?₁?₅=0.215,95%CI:0.142～0.309）,and direct effect of intercept of excessive daytime sleepiness on the intercept of activities of daily living was statistically significant（?₃=0.207,95%CI:0.082～0.329）;therefore,the intercept of autonomic dysfunction had a partial mediating effect.The indirect effect of slope of excessive daytime sleepiness through the slope of autonomic dysfunction on the slope of activities of daily living was statistically significant（ab=0.190,95%CI:0.085～0.326）,and direct effect of slope of excessive daytime sleepiness on the slope of activities of daily living was statistically significant（c’=0.327,95%CI:0.102～0.567）;therefore,the slope of autonomic dysfunction had a partial mediating effect.In summary,the mediating effects between the intercept and between the slope were all statistically significant for autonomic dysfunction,and thus a longitudinal mediation effect existed for this variable.Conclusions:With the progression of the disease,excessive daytime sleepiness,depression,autonomic dysfunction in patients with Parkinson’s disease are gradually aggravating,and activities of daily living are gradually declining.Depression and autonomic dysfunction act the longitudinal mediator variables that the excessive daytime sleepiness affecting the activities of daily living.With the aggravation of excessive daytime sleepiness in patients with Parkinson’s disease,the level of depression and autonomic dysfunction will also increase,which will reduce the activities of daily living in patients.Therefore,in the clinical work and preventive health care of Parkinson’s disease,effective prevention and intervention measures can be taken according to the depression and autonomic nervous function of patients to improve the activities of daily living of patients with Parkinson’s disease.