Treatment practices of patients with advanced kidney disease in the US Department of Veterans Affairs, 2000-2011

It is not known what proportion of US patients with advanced chronic kidney disease (CKD) receive renal replacement therapy (RRT) with maintenance dialysis or kidney transplant. In other developed countries, receipt of RRT is highly age-dependent and is the exception rather than the rule at older ages. We conducted a retrospective study of a national cohort of 28,568 adults who were receiving care within the Department of Veterans Affairs (VA) and had very advanced CKD (i.e., a sustained estimated glomerular filtration rate <15 ml/min/1.73m2) between January 1, 2000 to December 31, 2009 to determine how often patients with advanced CKD do not receive RRT, the characteristics of these patients and the clinical context in which these decisions occur. We used linked administrative data from the US Renal Data System (US national registry of RRT or USRDS), VA and Medicare to identify cohort members who received RRT during follow-up through October 1, 2011 (n=19,165). Of the 9,403 patients who did not receive RRT, we performed an in-depth review of VA-wide electronic medical records for a 25% randomly selected sample (n=2,252) to determine the treatment status of their CKD. We used inductive and deductive approaches for content analysis to complete medical record review. Initially, two nephrologists (S.P.Y.W. and A.M.O.) reviewed the progress notes of 200 randomly selected patients in the sample to identify clinically distinct groups with respect to the decision for dialysis to treat their advanced CKD (ie., received dialysis, discussing and/or preparing for dialysis, and decision against dialysis). The remaining 2,052 patients in the sample were assigned to a pre-specified treatment group. The results of chart review were used to estimate the proportion and 95% confidence interval (CI) of the overall cohort expected to belong to each treatment group and the estimated distribution of treatment groups within each age group. We then identified patients with an administrative record of having received RRT during follow-up based on USRDS enrollment or dialysis procedure codes and assigned them as the referent group in between-group comparisons of socio-demographic and clinical characteristics. We assessed the characteristics associated with membership in each treatment group using a multinomial logistic regression model adjusted for all baseline patient characteristics and calendar year of cohort entry. Sensitivity analyses were conducted in which models were developed after stratification by tertile of Gagne comorbidity score to evaluate for differences in treatment practices based on burden of comorbidity. Overall, two-thirds (67.1%) of cohort members received RRT based on linked administrative data. Results of the chart review determined that an additional 7.5% (95% CI 7.2-7.8) of cohort members had in fact received dialysis that was not captured in USRDS or administrative data, 10.9% (95% CI 10.6-11.3) were preparing for and/or discussing dialysis but had not started dialysis at most recent follow-up, and in 14.5% (95% CI 14.1-14.9), a decision had been made by the patients themselves, their family members and/or healthcare provider not to pursue dialysis. Compared with the referent group, patients in whom a decision against dialysis had been made were older, more often white, had a higher burden of comorbidity and had less nephrology care in the year prior to cohort entry. The percentage of cohort members who received or were preparing to receive RRT ranged from 96.2% (95% CI 94.4-97.4) for those <45 years to 53.3% (95% CI 50.7-55.9) for those aged ≥85 years. Results were similar after stratification by comorbidity score. In conclusion, in this large US cohort of patients with advanced CKD, the majority received or were preparing to receive RRT. This was true even among the oldest patients with the highest burden of comorbidity.