Difference in the mortality of the CABRI diabetic and nondiabetic populations and its relation to coronary artery disease and the revascularization mode

In diabetics with coronary artery disease (CAD), there remains uncertainty as to whether revascularization by percutaneous transluminal coronary angio plasty (PTCA) or coronary artery bypass surgery (CABG) is preferable. To ad dress this, 4-year mortality and level of pre- and postrevascularization an giographic CAD (measured by a series of coronary scores) were compared betw een both diabetics and nondiabetics and between revascularization modes in the Coronary Angioplasty versus Bypass Revascularization Investigation popu lation as a whole, and then substratified by diabetic status and then by pr ocedure to which they were randomized. The 1,054 randomized subjects contai ned 125 diabetics (11.9%) who had significantly greater mortality than nond iabetics (RR 2.19, p = 0.001), Among diabetics or nondiabetics, there was n o significant mortality difference between those randomized to PTCA versus those to CABG, Diabetics randomized to PTCA and those to CABG had higher mo rtalities than respective nondiabetics; the association reached significanc e only in the former (RR 2.41, p = 0.002), All subgroups had similar prerev ascularization CAD. Postrevascularization residual CAD was consistently sig nificantly greater in PTCA than in respective CABG subgroups, Most measurem ents of CAD were greater in diabetic than in nondiabetic subgroups, but non e was significant, In the Coronary Angioplasty versus Bypass Revascularizat ion Investigation, diabetics had double the mortality of nondiabetics; this difference was statistically significant both for the entire population an d for those randomized to WCA, but not for those randomized to CABG. Among diabetics or nondiabetics, there was no significant mortality difference be tween PTCA and CABG, The higher diabetic mortality was more likely related to more rapid disease progression than to greater postrevascularization dis ease. (C) 2001 by Excerpta Medico, Inc.