Author's reply

Abstract

We appreciate Dr Zhang's interest in our study [[1]Nakamura M. Yamashita T. Yajima J. Oikawa Y. Ogasawara K. Sagara K. Koike A. Kirigaya H. Nagashima K. Otsuka T. Uejima T. Funada R. Matsuno S. Suzuki S. Sawada H. et al.Impact of early statin initiation on secondary prevention in Japanese patients with coronary artery disease.J Cardiol. 2011; 57: 172-180Abstract Full Text Full Text PDF PubMed Scopus (15) Google Scholar] and the opportunity to discuss some issues. We also congratulate Dr Zhang and coworkers for their studies of the US National Heart, Lung, and Blood Institute (NHLBI) Dynamic Registry, which showed the effect of statins on reduction in mortality after percutaneous coronary intervention (PCI), consistent with our results, and the meta-analysis, which showed that statins were significantly associated with reduced repeat revascularization, but are unfortunately not associated with reduced mortality rate in patients undergoing PCI. As stated in our article, the relatively small size of the study population is one of the limitations. Propensity score analysis may be helpful for adjusting confounding factors efficiently. Moreover, the small number of events could lead to overestimation of the drug effects. We agree on these points with his comment. Therefore, a study with a larger population is now in progress and should allay his concerns. However, several previous studies using propensity score analysis have shown that the effect of early-initiated statins against death provided a similar level of risk reduction to our results in coronary artery disease (CAD) patients with or without PCI [2Lenderink T. Boersma E. Gitt A.K. Zeymer U. Wallentin L. Van de Werf F. Hasdai D. Behar S. Simoons M.L. Patients using statin treatment within 24 h after admission for ST-elevation acute coronary syndromes had lower mortality than non-users: a report from the first Euro Heart Survey on acute coronary syndromes.Eur Heart J. 2006; 27: 1799-1804Crossref PubMed Scopus (61) Google Scholar, 3Garot P. Bendaoud N. Lefèvre T. Morice M.C. Favourable effect of statin therapy on early survival benefit at the time of percutaneous coronary intervention for ST-elevation myocardial infarction and shock.EuroIntervention. 2010; 6: 350-355Crossref PubMed Scopus (13) Google Scholar]. We think the main topic in Dr Zhang's letter is, at least from the clinical perspective, whether statins, especially early-initiated statins, can reduce the repeat revascularization rate. Our study cannot reveal the effect of early statin initiation on reduction in target lesion revascularization (TLR). Here, we need to underscore the necessity to distinguish precisely between TLR and target vessel revascularization or non-target vessel revascularization (and combined repeat revascularization) when discussing the endpoint about repeat revascularization. It has not been clearly established whether statins can provide a benefit in reducing the incidence of restenosis after stent implantation. In fact, both the NHLBI Dynamic Registry and the meta-analysis performed by Dr Zhang et al. showed no effect against TLR, consistent with our result. In addition, when we consider these revascularization rates, especially TLR, the procedures during stent deployment, such as with or without intravascular ultrasound guidance, have been reported to be an indispensable factor [4Mintz G.S. Weissman N.J. Intravascular ultrasound in the drug-eluting stent era.J Am Coll Cardiol. 2006; 48: 421-429Abstract Full Text Full Text PDF PubMed Scopus (137) Google Scholar, 5Romagnoli E. Sangiorgi G.M. Cosgrave J. Guillet E. Colombo A. Drug-eluting stenting: the case for post-dilation.JACC Cardiovasc Interv. 2008; 1: 22-31Abstract Full Text Full Text PDF PubMed Scopus (62) Google Scholar]. Revascularization rate could be also influenced by the follow-up method because routine angiographic follow-up increases the detection rate in restenosis and de novo stenosis. For these reasons, the conclusions drawn from Dr Zhang and coworkers’ reports of their studies may not apply to our study populations with CAD who underwent PCI because of the differences in endpoint, patient backgrounds, and follow-up method. As mentioned in our article, there are some possible explanations for the discrepancy between the effects of early initiation of statins on mortality and TLR. Although we do not have the clear answer for this discrepancy, we believe from our results and previously published reports that early-initiated statins can produce a beneficial risk reduction in mortality for Japanese CAD patients in real-world clinical practice.