Department of Rheumatology, Dudley Group of Hospitals NHS Trust, The Guest Hospital, Tipton Road, Dudley, West Midlands DY1 4SE, UK
Correspondence to: G. D. Kitas. E-mail: g.d.kitas{at}bham.ac.uk
We thank Mpofu and colleagues for their interest in our article. We entirely agree that more research is needed to identify the mechanisms underlying the development of IHD in RA. We only use the parallelism with type 2 diabetes in the context of public health significance and as a pointer towards a possible approach for the prevention and management of IHD in RA. We do not propose that the pathogenesis of the vasculopathy associated with the two conditions is the same, apart from the fact that they both appear to associate with some clustering of classical cardiovascular risk factors.
We also agree that, from the practical perspective, it is very important to identify predictive markers of IHD in RA, and microalbuminuria is a very reasonable candidate for the reasons that Mpofu and colleagues clearly outline. However, we disagree with the conclusion that this simple test cannot be used as a surrogate marker for IHD or IHD risk in RA. The prevalence of microalbuminuria in this study is much lower than that detected by Pedersen et al. [1], although it compares well to that reported by other investigators [2, 3]. This may be due to significant differences in the populations studied (for example, Pedersen's study included several patients on gold and penicillamine). The low prevalence of microalbuminuria in a disease (RA) associated with a high prevalence of IHD is not in itself sufficient to justify their conclusion; it may well be that microalbuminuria has very poor sensitivity but very high specificity for IHD in RA. Moreover, the present study addressed the prevalence of microalbuminuria in an RA patient cohort of unknown sex composition, selected for the absence of at least some cardiac risk factors (e.g. hypertension and diabetes) and for taking in its majority (65%) a disease-modifying drug (methotrexate) which may relate to better cardiovascular outcome [4], and of unknown cardiovascular status, at least as to the presence or absence of IHD.
Prospective studies, designed specifically for the purpose, in representative RA populations, with clear definitions of IHD would be the ideal way to address the very important practical issue of predictors of IHD in RA.
The authors have declared no conflicts of interest.
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