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

Abstract

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.