A Clinical Risk Prediction Tool for 6-Month Mortality After Dialysis Initiation Among Older Adults.

BACKGROUND

Information on an individual's risk for death following dialysis therapy initiation may inform the decision to initiate maintenance dialysis for older adults. We derived and validated a clinical risk prediction tool for all-cause mortality among older adults during the first 6 months of maintenance dialysis treatment.

STUDY DESIGN

Prediction model using retrospective administrative and clinical data.

SETTING & PARTICIPANTS: We linked administrative and clinical data to define a cohort of 2,199 older adults (age ≥ 65 years) in Alberta, Canada, who initiated maintenance dialysis therapy (excluding acute kidney injury) in May 2003 to March 2012.

CANDIDATE PREDICTORS

Demographics, laboratory data, comorbid conditions, and measures of health system use.

OUTCOMES

All-cause mortality within 6 months of dialysis therapy initiation.

ANALYTICAL APPROACH

Predicted mortality by logistic regression with 10-fold cross-validation.

RESULTS

375 (17.1%) older adults died within 6 months. We developed a 19-point risk score for 6-month mortality that included age 80 years or older (2 points), glomerular filtration rate of 10 to 14.9mL/min/1.73m (1 point) or ≥15mL/min/1.73m (3 points), atrial fibrillation (2 points), lymphoma (5 points), congestive heart failure (2 points), hospitalization in the prior 6 months (2 points), and metastatic cancer (3 points). Model discrimination (C statistic = 0.72) and calibration (Hosmer-Lemeshow χ=10.36; P=0.2) were reasonable. As examples, a score < 5 equated to <25% of individuals dying in 6 months, whereas a score > 12 predicted that more than half the individuals would die in the first 6 months.

LIMITATIONS

The tool has not been externally validated; thus, generalizability cannot be assessed.

CONCLUSIONS

We used readily available clinical information to derive and internally validate a 7-variable tool to predict early mortality among older adults after dialysis therapy initiation. Following successful external validation, the tool may be useful as a clinical decision tool to aid decision making for older adults with kidney failure.