Advertisement

Authors' Reply

      We acknowledge that it is possible that the proportion of very late stent thrombosis using 1 minus the Kaplan-Meier curve might have biased our estimate of the number of stent thromboses, because of the competing risk for death. We have performed a new analysis using the methods suggested by Dr. Schutt (Figure 1) .
      • Gooley T.A.
      • Leisenring W.
      • Crowley J.
      • Storer B.E.
      Estimation of failure probabilities in the presence of competing risks: new representations of old estimators.
      • Coviello C.
      • Boggess M.
      Cumulative incidence estimation in the presence of competing risks.
      We have validated this using the manual approach. When the competing risk for death is considered, it does not appear to drastically modify our results. The very small difference between these curves could be explained by the low rate of events. Previous studies in this field have not taken competing risks into consideration (see references 7 and 10 in our original report).
      • Barone-Rochette G.
      • Foote A.
      • Motreff P.
      • Vanzetto G.
      • Quesada J.L.
      • Danchin N.
      • Machecourt J.
      EVASTENT Investigators
      Stent-related cardiac events beyond three years after implantation of the sirolimus-eluting stent (from the EVASTENT patients).
      To allow readers to compare our results with those of other research groups, we used the same methods as they did. Potentially, a small difference could be explained by the fact that for many patients (with stent thrombosis), stent thrombosis was the cause of death.
      Figure thumbnail gr1
      Figure 1Kaplan-Meier curve and new analysis using the methods suggested by Dr. Schutt. CI = cumulative incidence; CR = competing risk; 1-KM = complement of Kaplan-Meier estimate; ST = stent thrombosis.
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to American Journal of Cardiology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      Reference

        • Gooley T.A.
        • Leisenring W.
        • Crowley J.
        • Storer B.E.
        Estimation of failure probabilities in the presence of competing risks: new representations of old estimators.
        Stat Med. 1999; 18: 695-706
        • Coviello C.
        • Boggess M.
        Cumulative incidence estimation in the presence of competing risks.
        Stata J. 2004; 4: 103-112
        • Barone-Rochette G.
        • Foote A.
        • Motreff P.
        • Vanzetto G.
        • Quesada J.L.
        • Danchin N.
        • Machecourt J.
        • EVASTENT Investigators
        Stent-related cardiac events beyond three years after implantation of the sirolimus-eluting stent (from the EVASTENT patients).
        Am J Cardiol. 2011; 108: 1401-1407

      Linked Article

      • Analysis of Very Late In-Stent Thrombosis in the EVASTENT Patients
        American Journal of CardiologyVol. 109Issue 7
        • Preview
          I read with interest the recent report by Barone-Rochette et al1 describing the 6-year follow-up of the EVASTENT (Cost-Effectiveness of Sirolimus-Eluting Stents in Patients With and Without Diabetes) matched-cohort registry. In my opinion, the investigators may have inappropriately used 1 minus the Kaplan-Meier curve in Figures 1 and 2 to estimate the probability of failure (very late stent thrombosis) in the setting of a competing risk (namely, death). The misuse of the 1 minus the Kaplan-Meier curve in the setting of competing risks is well described2 and is known to cause biased results.
        • Full-Text
        • PDF