If apoB is so good, why isn't everybody measuring it? One reason why we need The Netherlands Journal of Medicine!

I recently had the privilege of giving a state-of-the-art lecture on the clinical value of apoB to the residents and staff of the Department of Internal Medicine of the Radboud University Nijmegen Medical Centre after which residents reviewed two recent key papers: the Northwick Park Heart Study 1 and the INTERHEART study. 2 One resident concluded his analysis with the question: if apoB is so good, why isn't everybody doing it? All at once, I felt everyone's eyes on me: such a simple question, such a difficult answer. My answer was inadequate then and will almost certainly be inadequate now. But I know it is tied in some way to another question: Why do we need a journal such as the Netherlands Journal of Medicine? I am going to try to answer both: the first by listing the relevant facts, the second by suggesting that we in modern academic medicine are less secure and less confident intellectually than we used to be. The remedy, I believe, is to rediscover our own strengths and by doing so to recover our independence. One way to do so is to encourage independent analyses of major issues in journals such as this. What is plasma apoB? Each atherogenic particle – that is to say, each VLDL, IDL, LDL and Lp(a) particle – contains one molecule of apoB100 3 Each chylomicron and chylomicron remnant particle contains one molecule of apoB48. All the stand-ardised, automated assays that measure total plasma apoB recognise both apoB100 and apoB48. However, except in type III hyperlipoproteinaemia, there are so few apoB48 particles present in plasma, even during the peak postprandial period, that total apoB is not affected. This means that for clinical practice apoB does not have to be measured fasting, but can be determined at the patient's convenience. LDL, the most important of the atherogenic particles, account for more than 90% of total plasma apoB particles and so LDL particle number is the principal determinant of the atherogenic particle number. What is the evidence that apoB is better than any of the other cholesterol indices for estimating the risk of vascular disease? The evidence is overwhelming. To be sure, the initial generation of cross-sectional and nested case-control studies yielded mixed results, in part because the assays were not standardised, in part because the wrong question was asked (Did the indices being compared predict haemodynamically significant coronary disease – which …