Dialysis Timing May Be Deferred Toward Very Late Initiation: An Observational Study

The optimal timing to initiate dialysis among patients with an estimated glomerular filtration rate (eGFR) of < 5 mL/min/1.73 m2 is unknown. We hypothesized that dialysis initiation time can be deferred in this population even with high uremic burden. A case-crossover study with case (0-30 days before dialysis initiation [DI]) and control (90-120 days before DI) periods was conducted in 1,079 hemodialysis patients aged 18-90 years at China Medical University Hospital between 2006 and 2015. The uremic burden was quantified based on 7 uremic indicators that reached the predefined threshold in case period, namely hemoglobin, serum albumin, blood urea nitrogen, serum creatinine, potassium, phosphorus, and bicarbonate. Dialysis timing was classified as standard (met 0-2 uremic indicators), late (3-5 indicators), and very late (6-7 indicators). Median eGFR-DI of the 1,079 patients was 3.4 mL/min/1.73 m(2) and was 2.7 mL/min/1.73 m(2) in patients with very late initiation. The median follow-up duration was 2.42 years. Antibiotics, diuretics, antihypertensive medications, and non-steroidal anti-inflammatory drugs (NSAIDs) were more prevalently used during the case period. The fully adjusted hazards ratios of all-cause mortality for the late and very late groups were 0.97 (95% confidence interval 0.76-1.24) and 0.83 (0.61-1.15) compared with the standard group. It is safe to defer dialysis initiation among patients with chronic kidney disease (CKD) having an eGFR of < 5 mL/min/1.73 m(2) even when patients having multiple biochemical uremic burdens. Coordinated efforts in acute infection prevention, optimal fluid management, and prevention of accidental exposure to NSAIDs are crucial to prolong the dialysis-free survival.