Trajectories of kidney function decline in the 2 years before initiation of long-term dialysis

BACKGROUND: Little is known about patterns of kidney function decline leading up to initiation of chronic dialysis. STUDY DESIGN: Retrospective cohort study. SETTING AND PARTICIPANTS: 5,606 VA patients who initiated chronic dialysis in 2001–2003. Predictor: Trajectory of estimated glomerular filtration rate (eGFR) during the two year period before dialysis initiation. OUTCOMES AND MEASUREMENTS: Patient characteristics and care practices before and at the time of dialysis initiation and survival after initiation. RESULTS: We identified four distinct trajectories of eGFR during the two year period before dialysis initiation: 62.8% of patients had persistently low levels of eGFR below 30 ml/min/1.73 m(2) (mean eGFR slope 7.7 ±4.7 (SD) ml/min/1.73 m(2) per year); 24.6% had progressive loss of eGFR from levels around 30–59 ml/min/1.73 m(2) (mean eGFR slope 16.3 ±7.6 ml/min/1.73 m(2) per year); 9.5% had accelerated loss of eGFR from levels above 60 ml/min/1.73 m(2) (mean eGFR slope 32.3 ±13.4 ml/min/1.73 m(2) per year); and 3.1% experienced catastrophic loss of eGFR within six months or less from levels above 60 ml/min/1.73 m(2). Patients with steeper eGFR trajectories were more likely to have been hospitalized and to have an inpatient diagnosis of acute kidney injury. They were less likely to have received recommended pre-dialysis care and had a higher risk of death in the first year after dialysis initiation. CONCLUSIONS: There is substantial heterogeneity in patterns of kidney function loss leading up to initiation of chronic dialysis, perhaps calling for a more flexible approach toward preparing for end-stage renal disease