Fatigue Is Associated with Increased Risk of Mortality in Patients on Chronic Hemodialysis.

BACKGROUND: Little is known about the correlation between fatigue and survival in patients on chronic hemodialysis and whether fatigue is an independent predictor of outcome above and beyond the effects of depression. The aim of the present study was to determine if fatigue is a predictor of mortality in patients on chronic hemodialysis (CHP) and if this occurs independently of the symptoms of depression.

METHODS: CHP referring to the Hemodialysis Service of the Università Cattolica of Rome, Italy between November 2007 and January 2015 were studied. Demographic, clinical, and laboratory data were recorded for each patient at the moment of the inclusion in the study. Fatigue levels were assessed in patients using the Vitality Scale of SF-36 (SF-36 VS), functional ability by the activities of daily living (ADL) and instrumental activities of daily living (IADL), depressive symptoms through the Geriatric Depression Scale (GDS), cognitive function using the Mini Mental State Examination (MMSE), and comorbidity through the Charlson Comorbidity Index (CCI). Patients were grouped into four groups (quartiles): Quartile 1 (Q1), >65; Q2, ≥50 to <65; Q3, ≥35 to <50; Q4, <35.

RESULTS: We studied 126 patients: 11 were transplanted and 53 died. Patients who later died were older and had a worse cognitive performance, higher CCI and GDS scores, lower ADL, IADL and SF-36 VS scores, lower serum creatinine and albumin levels. Kaplan-Meier survival was significantly lower in Q4 than in Q1 (p = 0.0001). According to Cox regression analysis, higher fatigue (Q4) was associated with a higher risk of mortality (HR, 95% CI: 5.29, 2.2-12.73).

CONCLUSION: Fatigue is associated with an increased risk of mortality in CHP, with the relationship independent of symptoms of depression. Fatigue should be assessed routinely and may be a potential target of interventions that aim to reduce mortality in CHP.