Dimensions of Depressive Symptoms and Their Association With Mortality, Hospitalization, and Quality of Life in Dialysis Patients: A Cohort Study.

OBJECTIVE: Unraveling specific dimensions of depressive symptoms may help to improve screening and treatment in dialysis patients. We aimed to identify the best-fitting factorial structure for the Beck Depression Inventory-II (BDI) in dialysis patients and to assess the relation of these structure dimensions with quality of life (QoL), hospitalization, and mortality. METHODS: This prospective study included chronic dialysis patients from 10 dialysis centers in five hospitals between 2012 and 2017. Dimensions of depressive symptoms within the BDI were analyzed using confirmatory factor analysis. To investigate the clinical impact of these dimensions, the associations between symptom dimensions and QoL, hospitalization rate, and mortality were investigated using logistic, Poisson, and Cox proportional hazard regression models. Multivariable regression models included demographic, social, and clinical variables. RESULTS: In total, 687 dialysis patients were included. The factor model that included a general and a somatic factor provided the best-fitting structure of the BDI-II. Only the somatic dimension scores were associated with all-cause mortality (hazard ratio of 1.7 [1.2-2.5], p < .007) in the multivariable model. All dimensions were associated with increased hospitalization rate and reduced QoL. CONCLUSIONS: The somatic dimension of the BDI-II in dialysis patients was associated with all-cause mortality, increased hospitalization rate, and reduced QoL. Other dimensions were associated with hospitalization rate and decreased QoL. These findings show that symptom dimensions of depression have differential association with adverse clinical outcomes. Future studies should take symptom dimensions into account when investigating depression-related pathways, screening, and treatment effects in dialysis patients.

Symptom dimensions of anxiety and their association with mortality, hospitalization and quality of life in dialysis patients.

OBJECTIVE: Symptoms of anxiety are highly prevalent in dialysis patients and are associated with adverse clinical outcomes. Identifying symptom dimensions may help to understand the pathophysiology, improve screening and guide treatment. Currently, there are no data on symptom dimensions of anxiety in dialysis patients. This study aimed to identify the best fitting dimensional model for anxiety in dialysis patients and assess the association between symptom dimensions of anxiety and adverse clinical outcomes. METHODS: This study is a prospective observational cohort study including patients from 10 urban dialysis centers between 2012 and 2017. Anxiety symptoms were measured using the self-reported questionnaire Beck Anxiety Inventory. Confirmatory factor analysis was used to identify symptom dimensions. The association between dimensions and mortality, hospitalization and quality of life was investigated using stepwise cox, poisson and lineair regression models. Multivariable models included demographic, social, laboratory and clinical variables to adjust for possible confounding. RESULTS: In total 687 chronic dialysis patients were included. A Somatic and Subjective anxiety dimension were identified. Only Somatic anxiety symptoms showed an association with increased risk of hospitalization and mortality (Rate Ratio 1.73 (1.45-2.06) p = .007 and Hazard Ratio 1.65 (1.15-2.37) p = .007 respectively). These associations were independent from somatic comorbidity. All symptom dimensions of anxiety showed an association with Quality of Life. CONCLUSION: This study shows that anxiety is common in chronic dialysis patients and comprises of a somatic, subjective, and a total score. The discrimination between anxiety dimensions can be useful for clinical practice, as they are related to different clinical outcomes.