Predialysis psychoeducational intervention and coping styles influence time to dialysis in chronic kidney disease

Background: Consensus endorses predialysis intervention before the onset of end-stage renal disease. In a previous study, predialysis psychoeducational intervention (PPI) extended time to dialysis therapy by a median of 6 months. We undertook to replicate and extend this finding by examining hypothesized mechanisms. Methods: We used an inception-cohort, prospective, randomized, controlled trial with follow-up to evaluate an intervention that included an interactive 1-on-1 slide-supported educational session, a printed summary (booklet), and supportive telephone calls once every 3 weeks. Participants were sampled from 15 Canadian (tertiary care) nephrology units and included 297 patients with progressive chronic kidney disease (CKD) expected to require renal replacement therapy (RRT) within 6 to 18 months. The main outcome was time to dialysis therapy (censored at 18 months if still awaiting RRT). Results Time to dialysis therapy was significantly longer (median, 17.0 months) for the PPI group than the usual-care control group (median, 14.2 months; Cox's proportional hazards analysis, controlling for general nonrenal health, P < 0.001). Coping by avoidance of threat-related information (called blunting) was associated with shorter times to dialysis therapy (P < 0.032). A group x blunting interaction (P < 0.069) indicated: (1) time to dialysis therapy was shortened in the usual-care group, especially when patients coped by blunting; but (2) time to dialysis therapy was extended with PPI, even among patients who coped by blunting. Knowledge acquisition predicted time to dialysis therapy (r = 0.14; P < 0.013). Time to dialysis therapy was unrelated to depression or social support. Conclusion: PPI extends time to dialysis therapy in patients with progressive CKD. The mechanism may involve the acquisition and implementation of illness-related knowledge. Routine follow-up also may be especially important when patients cope by avoiding threat-related information.