Time- And Hemoglobin-Dependent Clinical Variability In Patients On Dialysis

RATIONALE: This was a single-center, observational, retrospective chart review analysis of patients on dialysis for the treatment of chronic kidney disease. OBJECTIVE: This study examined relationships of erythropoietin (EPO) dose and weight gain (WG) with inter- and intradialytic blood pressure (BP), as well as explored clinical markers to predict patients' status over time. METHODS: Patients were grouped according to hemoglobin (Hb) levels (low, target, high, and fluctuation). Baseline and wave 1 (W1) distance varied among subjects. W1, W2, and W3 occurred consecutively. W3 occurred two months prior to current observation. RESULTS: Albumin, BP, glycemia, urea, and WG varied across Hb levels and time. Inter- and intra-dialytic BP were similar in patients receiving or not receiving anti-hypertensive therapy (anti-HTNt) from high and target groups. Few exceptions were observed in fluctuation (W1, intradialytic diastolic [DBP], P = 0.013; W1, intradialytic systolic [SBP], P = 0.016; current, interdialytic SBP: P = 0.011) and low groups (current, interdialytic DBP, P = 0.025). Regressions of inter- and intradialytic DBP and SBP as a function of EPO dose and WG intersessions adjusted for age across hemoglobin levels and time resulted in the highest relationships in patients not receiving anti-HTNt. Short-term relationships ranged from adjusted R2 = 0.70 (interdialytic DBP, high group) to 0.92 (intradialytic SBP, fluctuation group), while for the entire sample ranged from adjusted R2 = 0.53 (interdialytic DBP, fluctuation group) to 0.79 (intradialytic SBP, target group). Long-term relationships were observed only in patients who were not receiving anti-HTNt (adjusted R2 = 0.75, intradialytic DBP and SBP; adjusted R2 = 0.85, interdialytic SBP) and mostly in the entire sample from the fluctuation group (adjusted R2 = 0.39, intradialytic SBP; adjusted R2 = 0.49, interdialytic DBP). CONCLUSION: Short-term relationships and patients who were not receiving anti-HTNt had the strongest association levels. Assumptions of higher stability in the shortest distance and in patients receiving anti-HTNt, and lower stability in the fluctuation group were not confirmed. Patients’ Hb level and wave affected albumin, blood pressure, glycemia, urea, and WG.