• Defining a minimal clinically meaningful difference in 12-month estimated glomerular filtration rate for clinical trials in deceased donor kidney transplantation

      Mayne, Tracy J; Nordyke, Robert J; Schold, Jesse D; Weir, Matthew R; Mohan, Sumit (Blackwell Publishing, 2021-04-25)
      Background: A Minimal Clinically Meaningful Difference (MCMD) has not been defined for Estimated glomerular filtration rate (eGFR). Our goal was to define the MCMD for eGFR anchored to kidney graft failure. Methods: A systematic review of studies with 12‐month eGFR and subsequent renal graft failure was conducted. For observational studies, we calculated hazard ratio (HR) differences between adjacent eGFR intervals weighted by population distribution. Interventional trials yielded therapeutically induced changes in eGFR and failure risk. OPTN data analysis divided 12‐month eGFR into bands for Cox regressions comparing adjacent eGFR bands with a death‐censored graft survival outcome. Results: Observational studies indicated that lower eGFR was associated with increased death‐censored graft failure risk; each 5 ml/min/1.73 m2 12‐month eGFR band associated with a weighted incremental HR = 1.12 to 1.23. Clinical trial data found a 5 ml/min/1.73 m2 difference was associated with incremental HR = 1.16 to 1.35. OPTN analyses showed weighted mean HRs across 10, 7, and 5 ml/min/1.73 m2 bands of 1.47, 1.30, and 1.19. Conclusions: A 5 ml/min/1.73 m2 difference in 12‐month eGFR was consistently associated with ~20% increase in death‐censored graft failure risk. The magnitude of effect has been interpreted as clinically meaningful in other disease states and should be considered the MCMD in renal transplantation clinical trials.
    • Predictors of the start of declining eGFR in patients with systemic lupus erythematosus.

      Yip, Terry Cheuk-Fung; Saria, Suchi; Petri, Michelle; Magder, Laurence S (SAGE Publications Inc., 2020-10-28)
      The longitudinal eGFR levels of patients in the Hopkins Lupus Cohort were modelled by piecewise linear regression to evaluate the slope of different line segments. The slopes were classified into declining (≤-4 mL/min/1.73 m2 per year), stable (-4 to 4 mL/min/1.73 m2 per year), and increasing (≥4 mL/min/1.73 m2 per year) states. The transition rate between states and the impact of clinical parameters were estimated by a Markov model.