Letter by Baker et al Regarding Article, “Benefits and Risks of Corticosteroid Prophylaxis in Adult Cardiac Surgery: A Dose-Response Meta-Analysis”

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HomeCirculationVol. 120, No. 20Letter by Baker et al Regarding Article, “Benefits and Risks of Corticosteroid Prophylaxis in Adult Cardiac Surgery: A Dose-Response Meta-Analysis” Free AccessLetterPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessLetterPDF/EPUBLetter by Baker et al Regarding Article, “Benefits and Risks of Corticosteroid Prophylaxis in Adult Cardiac Surgery: A Dose-Response Meta-Analysis” William L. Baker, C. Michael White and Craig I. Coleman William L. BakerWilliam L. Baker University of Connecticut, Schools of Pharmacy/Hartford Hospital Evidence-Based Practice Center, Hartford, Conn Search for more papers by this author , C. Michael WhiteC. Michael White University of Connecticut, Schools of Pharmacy/Hartford Hospital Evidence-Based Practice Center, Hartford, Conn Search for more papers by this author and Craig I. ColemanCraig I. Coleman University of Connecticut, Schools of Pharmacy/Hartford Hospital Evidence-Based Practice Center, Hartford, Conn Search for more papers by this author Originally published17 Nov 2009https://doi.org/10.1161/CIRCULATIONAHA.109.872242Circulation. 2009;120:e163To the Editor:We read with great interest the meta-analysis by Ho and Tan1 on the impact of prophylactic corticosteroid use on atrial fibrillation in adult patients undergoing cardiac surgery. In their meta-analysis, Ho and Tan demonstrate that perioperative corticosteroid use significantly reduces the relative risk (RRR) of postoperative atrial fibrillation by 25%. They conducted subgroup analysis, stratifying studies to low-dose (<1000 mg hydrocortisone equivalents), medium-dose (1000 to 10 000 mg), and high-dose (>10 000 mg) groups, and then used meta-regression to assess whether the antifibrillatory (among other) benefits varied by corticosteroid dosing intensity. They conclude that the ability of corticosteroids to prevent atrial fibrillation “ … was not significantly different between different doses” and that low-dose corticosteroids should be used.We are concerned that Ho and Tan may be oversimplifying the dose-response relationship seen between corticosteroids and the reduction in atrial fibrillation risk. Although their subgroup analysis revealed that the RRRs achieved with different doses (RRRLow= 23%, RRRMedium=35%, RRRHigh=10%) were not statistically different, a failure to prove statistical significance does not rule out the possibility that a true difference exists. In fact, we believe that a thoughtful qualitative review of the above-mentioned results suggests that a U-shaped relationship exists, with medium doses showing the most benefit and low and high doses showing blunted antifibrillatory effects. Consequently, the use of meta-regression analysis to support the conclusions of subgroup analysis is inappropriate because this methodology assumes a linear relationship between corticosteroid dose and clinical outcome.2Furthermore, it is likely that the cut points used by Ho and Tan1 to define the different dosing categories may have contributed to their lack of significant findings. In a previous meta-analysis conducted by our research group evaluating the impact of corticosteroids on postoperative atrial fibrillation in cardiothoracic surgery patients,3 we also divided patients into 3 dosing strata but used different cut points. In our analysis, we found a similar U-shaped relationship (reduction in oddsLow=20%, reduction in oddsMedium=64%, reduction in oddsHigh=14%), with the studies in the medium-dose group showing the most benefit (P≤0.03 for interaction for low and high versus medium dose). In our article, we hypothesized that lower corticosteroid doses did not provide enough antiinflammatory potency to be beneficial, whereas the higher doses possibly worsened outcomes by promoting sodium and water reabsorption in addition to increased risk of infection and glucose abnormalities.3Given the present data, it should not be summarily assumed that no dose-response relationship exists. Additional research is needed to determine whether a U-shaped relationship exists and, if so, to elucidate the pharmacological rationale for the effect.DisclosuresNone. References 1 Ho KM, Tan JA. Benefits and risks of corticosteroid prophylaxis in adult cardiac surgery: a dose-response meta-analysis. Circulation. 2009; 119: 1853–1866.LinkGoogle Scholar2 Thompson SG, Higgins JPT. How should meta-regression analyses be undertaken and interpreted? Stats Med. 2002; 21: 1559–1573.CrossrefMedlineGoogle Scholar3 Baker WL, White CM, Kluger J, Denowitz A, Konecny CP, Coleman CI. Effect of perioperative corticosteroid use on the incidence of postcardiothoracic surgery atrial fibrillation and length of stay. Heart Rhythm. 2007; 4: 461–468.CrossrefMedlineGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetailsCited By Mahrose R, Elsayed A and Elshorbagy M Bisoprolol Versus Corticosteroid and Bisoprolol Combination for Prevention of Atrial Fibrillation After On-Pump Coronary Artery Bypass Graft Surgery, The Open Anesthesia Journal, 10.2174/2589645801913010018, 13:1, (18-24) November 17, 2009Vol 120, Issue 20 Advertisement Article InformationMetrics https://doi.org/10.1161/CIRCULATIONAHA.109.872242PMID: 19917892 Originally publishedNovember 17, 2009 PDF download Advertisement SubjectsCardiovascular Surgery