UC Davis

Background

A shared decision-making tool could help elderly patients with advanced chronic kidney disease decide about initiating dialysis therapy. Because mortality may be high in the first few months after initiating dialysis therapy, incorporating early mortality predictors in such a tool would be important for an informed decision. Our objective is to derive and validate a predictive risk score for early mortality after initiating dialysis therapy.

Study design

Retrospective observational cohort, with development and validation cohorts.

Setting & participants

US Renal Data System and claims data from the Centers for Medicare & Medicaid Services for 69,441 (aged ≥67 years) patients with end-stage renal disease with a previous 2-year Medicare history who initiated dialysis therapy from January 1, 2009, to December 31, 2010.

Candidate predictors

Demographics, predialysis care, laboratory data, functional limitations, and medical history.

Outcomes

All-cause mortality in the first 3 and 6 months.

Analytical approach

Predicted mortality by logistic regression.

Results

The simple risk score (total score, 0-9) included age (0-3 points), low albumin level, assistance with daily living, nursing home residence, cancer, heart failure, and hospitalization (1 point each), and showed area under the receiver operating characteristic curve (AUROC)=0.69 in the validation sample. A comprehensive risk score with additional predictors was also developed (with AUROC=0.72, high concordance between predicted vs observed risk). Mortality probabilities were estimated from these models, with the median score of 3 indicating 12% risk in 3 months and 20% in 6 months, and the highest scores (≥8) indicating 39% risk in 3 months and 55% in 6 months.

Limitations

Patients who did not choose dialysis therapy and did not have a 2-year Medicare history were excluded.

Conclusions

Routinely available information can be used by patients with chronic kidney disease, families, and their nephrologists to estimate the risk of early mortality after dialysis therapy initiation, which may facilitate informed decision making regarding treatment options.