Restricted mean survival time over 15 years for patients starting renal replacement therapy: Clinical Epidemiology in Nephrology

Background. The restricted mean survival time (RMST) estimates life expectancy up to a given time horizon and can thus express the impact of a disease. The aim of this study was to estimate the 15‐year RMST of a hypothetical cohort of incident patients starting renal replacement therapy (RRT), according to their age, gender and diabetes status, and to compare it with the expected RMST of the general population. Methods. Using data from 67 258 adult patients in the French Renal Epidemiology and Information Network (REIN) registry, we estimated the RMST of a hypothetical patient cohort (and its subgroups) for the first 15 years after starting RRT (cRMST) and used the general population mortality tables to estimate the expected RMST (pRMST). Results were expressed in three different ways: the cRMST, which calculates the years of life gained under the hypothesis of 100% death without RRT treatment, the difference between the pRMST and the cRMST (the years lost), and a ratio expressing the percentage reduction of the expected RMST: (pRMST − cRMST)/pRMST. Results. Over their first 15 years of RRT, the RMST of end‐stage renal disease (ESRD) patients decreased with age, ranging from 14.3 years in patients without diabetes aged 18 years at ESRD to 1.8 years for those aged 90 years, and from 12.7 to 1.6 years, respectively, for those with diabetes; expected RMST varied from 15.0 to 4.1 years between 18 and 90 years. The number of years lost in all subgroups followed a bell curve that was highest for patients aged 70 years. After the age of 55 years in patients with and 70 years in patients without diabetes, the reduction of the expected RMST was >50%. Conclusion. While neither a clinician nor a survival curve can predict with absolute certainty how long a patient will live, providing estimates on years gained or lost, or percentage reduction of expected RMST, may improve the accuracy of the prognostic estimates that influence clinical decisions and information given to patients.

[1]  Lihui Zhao,et al.  On the restricted mean survival time curve in survival analysis , 2016, Biometrics.

[2]  E. Dantony,et al.  Estimating the parameters of multi-state models with time-dependent covariates through likelihood decomposition , 2016, Comput. Biol. Medicine.

[3]  C. Couchoud,et al.  Development of a risk stratification algorithm to improve patient-centered care and decision making for incident elderly patients with end-stage renal disease. , 2015, Kidney international.

[4]  D. Schaubel,et al.  A Reassessment of the Survival Advantage of Simultaneous Kidney-Pancreas Versus Kidney-Alone Transplantation , 2015, Transplantation.

[5]  C. Couchoud,et al.  A simple clinical tool to inform the decision-making process to refer elderly incident dialysis patients for kidney transplant evaluation. , 2015, Kidney international.

[6]  O. Iyasere,et al.  Mortality in the Elderly on Dialysis: Is This the Right Debate? , 2015, Clinical journal of the American Society of Nephrology : CJASN.

[7]  Yoshiaki Uyama,et al.  Moving beyond the hazard ratio in quantifying the between-group difference in survival analysis. , 2014, Journal of clinical oncology : official journal of the American Society of Clinical Oncology.

[8]  Patrick Royston,et al.  Restricted mean survival time: an alternative to the hazard ratio for the design and analysis of randomized trials with a time-to-event outcome , 2013, BMC Medical Research Methodology.

[9]  L. Remontet,et al.  Probabilities of dying from cancer and other causes in French cancer patients based on an unbiased estimator of net survival: a study of five common cancers. , 2013, Cancer epidemiology.

[10]  M. Elsensohn,et al.  Modelling treatment trajectories to optimize the organization of renal replacement therapy and public health decision-making. , 2013, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association.

[11]  P. Lambert,et al.  Choosing the relative survival method for cancer survival estimation. , 2011, European journal of cancer.

[12]  P. Royston,et al.  The use of restricted mean survival time to estimate the treatment effect in randomized clinical trials when the proportional hazards assumption is in doubt , 2011, Statistics in medicine.

[13]  T. Blakely,et al.  Measuring cancer survival in populations: relative survival vs cancer-specific survival. , 2010, International journal of epidemiology.

[14]  P C Lambert,et al.  Estimating the crude probability of death due to cancer and other causes using relative survival models , 2010, Statistics in medicine.

[15]  R. Écochard,et al.  The Impact of Type 2 Diabetes on Mortality in End-Stage Renal Disease Patients Differs between Genders , 2009, Nephron Clinical Practice.

[16]  E. Villar,et al.  Relative mortality risk in chronic kidney disease and end-stage renal disease: the effect of age, sex and diabetes. , 2008, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association.

[17]  N. Sheerin,et al.  Dialysis or not? A comparative survival study of patients over 75 years with chronic kidney disease stage 5. , 2007, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association.

[18]  R. Écochard,et al.  Effect of age, gender, and diabetes on excess death in end-stage renal failure. , 2007, Journal of the American Society of Nephrology : JASN.

[19]  J. Estève,et al.  An overall strategy based on regression models to estimate relative survival and model the effects of prognostic factors in cancer survival studies , 2007, Statistics in medicine.

[20]  Paul Landais,et al.  The renal epidemiology and information network (REIN): a new registry for end-stage renal disease in France. , 2006, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association.

[21]  J. Schold,et al.  Long‐Term Renal Allograft Survival: Have we Made Significant Progress or is it Time to Rethink our Analytic and Therapeutic Strategies? , 2004, American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons.

[22]  G. Hédelin,et al.  Cancer incidence and mortality in France over the period 1978-2000. , 2003, Revue d'epidemiologie et de sante publique.

[23]  A A Tsiatis,et al.  Causal Inference on the Difference of the Restricted Mean Lifetime Between Two Groups , 2001, Biometrics.