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Published on: January 8, 2020
Late nephrology referral and mortality among patients with end-stage renal disease: a propensity score analysis
Waqar H Kazmi1, Gregorio T Obrador, Samina S Khan
1Department of Nephrology, Tufts-New England Medical Center, Boston, MA 02111, USA.
Background:
Late nephrology referral has been associated with adverse outcomes among patients with end-stage renal disease; however, its relationship to mortality is unclear. We examined the impact of timing of nephrology care relative to initiation of dialysis on mortality after initiation of dialysis.
Methods:
Data from the Dialysis Morbidity and Mortality Study - Wave II, a prospective study of incident dialysis patients, were used. Late referral (LR) was defined as first nephrology visit <4 months and early referral (ER) as first nephrology visit >or=4 months prior to initiation of dialysis. Propensity scores (PS) were estimated using logistic regression to predict the probability that a given patient was LR. A Cox proportional hazards model was built to examine the association between timing of nephrology referral and mortality.
Results:
The cohort was comprised of 2195 patients: 54% were males, 66% were Caucasians, 26% were African-Americans and 33% were referred late. A Cox proportional hazards analysis demonstrated that compared with ER patients, LR patients had a 44% higher risk of death at 1 year after initiation of dialysis [hazards ratio (HR) = 1.44; 95% confidence interval (CI): 1.15-1.80], which remained significant after adjusting for quintiles of PS (HR = 1.42; 95% CI: 1.12-1.80).
Conclusions:
Among patients with chronic kidney disease (CKD) who initiated dialysis, LR was associated with higher risk of death at 1 year after initiation of dialysis compared with ER.
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