Kidney Week

Abstract: TH-PO556

Does Longer Duration of Predialysis Care Improve Survival in People Treated with Dialysis?

Session Information

• CKD: Health Services, Disparities, Prevention
  November 02, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Chronic Kidney Disease (Non-Dialysis)

• 307 CKD: Health Services, Disparities, Prevention

Authors

• Liu, Ping, University of Calgary, Calgary, Alberta, Canada

Ping Liu,

• Quinn, Robert R., University of Calgary, Calgary, Alberta, Canada

Robert R. Quinn,

• Oliver, Matthew J., Sunnybrook Health Sciences Center, Toronto, Ontario, Canada

Matthew J. Oliver,

• Ronksley, Paul E., University of Calgary, Calgary, Alberta, Canada

Paul E. Ronksley,

• Hemmelgarn, Brenda, University of Calgary, Calgary, Alberta, Canada

Brenda Hemmelgarn,

• Quan, Hude, University of Calgary, Calgary, Alberta, Canada

Hude Quan,

• Hiremath, Swapnil, University of Ottawa, Ottawa, Ontario, Canada

Swapnil Hiremath,

• Bello, Aminu K., UNIVERSITY OF ALBERTA, Edmonton, Alberta, Canada

Aminu K. Bello,

• Blake, Peter G., London Health Sciences Centre, London, Ontario, Canada

Peter G. Blake,

• Garg, Amit X., London Health Sciences Centre, London, Ontario, Canada

Amit X. Garg,

• Johnson, John F., London Health Sciences Centre, London, Ontario, Canada

John F. Johnson,

• Verrelli, Mauro, University of Manitoba, Winnipeg, Manitoba, Canada

Mauro Verrelli,

• Zacharias, James M., University of Manitoba, Winnipeg, Manitoba, Canada

James M. Zacharias,

• Abd elhafeez, Samar, High Institute of Public Health, Alexandria, Egypt

Samar Abd elhafeez,

• Tonelli, Marcello, University of Calgary, Calgary, Alberta, Canada

Marcello Tonelli,

• Ravani, Pietro, University of Calgary, Calgary, Alberta, Canada

Pietro Ravani,

Background

Guidelines recommend early referral to nephrology care for people with chronic kidney disease, based on observational studies showing that longer nephrology care before dialysis start (predialysis care, PDC) is associated with lower mortality after dialysis start. This association may be observed because PDC truly improves patient outcomes, or because healthier people with an uncomplicated course of disease will have both longer PDC and better outcomes. We designed this study to assess whether the survival benefit of longer PDC exists after accounting for the potential confounding effect of acute events (markers of disease course) that may also be affected by prior PDC.

Methods

We did a retrospective cohort study in adults with kidney failure who initiated dialysis not following a failed kidney transplant between 2004 and 2014 in five Canadian programs. Data were collected from medical records and double-reviewed by two investigators.

Results

Of the 3152 participants: 23% had no PDC; 8%, 10%, and 59% received 1-119, 120-364, and ≥365 days of PDC, respectively. When we ignored markers of acute events (including unplanned dialysis start and higher residual kidney function around dialysis start) as in prior studies, longer PDC was associated with lower mortality (Hazard Ratio_{120-364 vs. 0-119 d} 0.60, 95% CI 0.46-0.78; HR_{≥365 vs. 0-119 d} 0.60 (0.51-0.71), standard Cox model adjusted for demographics, laboratory and clinical characteristics). When we accounted for markers of acute events, this association was weaker and no longer significant (HR_{120-364 vs. 0-119 d} 0.84 (0.60-1.18); HR_{≥365 vs. 0-119 d} 0.88 (0.69-1.13), marginal structural Cox model).

Conclusion

Current guidelines on early nephrology referral are based on studies that may have overestimated the survival benefit of longer PDC, because they may have inadequately addressed confounding by occurrence of acute events.