Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
 
Articles by Matthew J. McQueen
Total Records ( 2 ) for Matthew J. McQueen
  Allan D. Sniderman , Ken Williams , Matthew J. McQueen and Curt D. Furberg
  The meta-analysis of the Emerging Risk Factor Collaboration demonstrated that the hazard ratios (HR) of the major cholesterol markers and the major apolipoproteins for vascular disease did not differ significantly in the studies they examined. Their conclusion was that they were functionally interchangeable. We believe there are important limitations in the execution of this study. Nevertheless, even if their findings are correct for groups, their conclusions do not follow for individuals. Conventionally, the HR expresses the increase in risk per standard deviation change for that parameter in a group. However, the predicted risk of vascular disease from an atherogenic parameter depends on its concentration within the individual. Depending on the composition of the apoB lipoproteins, individuals may have either concordant or discordant levels of cholesterol and apoB. For those who are concordant, the two markers predict equal risk. For those who are discordant, the predicted risks for the individual are different. We demonstrate that substantial discordance in the individual HR of non-high-density lipoprotein cholesterol and apoB is common. The result is that even with identical overall HR, apoB points to higher risk in a substantial number of individuals whereas the converse is the case for non- high-density lipoprotein cholesterol. Because we are concerned with risks in individuals, not groups, this discordance is important to appreciate and analyze. Our objective should be to learn how to combine the information from parameters rather than eliminate them and we need to focus on evaluation of risk in individuals and not just groups.
  Allan D. Sniderman , Shofiqui Islam , Salim Yusuf and Matthew J. McQueen
 

Background

Patients with increased numbers of cholesterol-depleted apolipoprotein B (apoB) particles frequently have multiple other abnormalities, which might confound the comparison of apoB and non-high-density-lipoprotein-cholesterol (non-HDL-C) as markers of cardiovascular risk.

Objective

We wanted to determine whether the superiority of apoB over non-HDL-C as a marker of cardiovascular risk in the INTERHEART study is due to such variables that act as confounders of the primary comparison.

Methods

To test for confounding, cases and controls were first separated into 3 groups on the basis of the percentile levels within the study of non-HDL-C and apoB with discordance defined as a difference of 5 percentile points. Logistic regression was used to compute odds ratio of myocardial infarction (as an outcome) for different categories, assuming concordance as reference adjusted for other confounders.

Results

Plasma triglyceride and non-HDL-C levels were highest in the discordant group with lowest risk and lowest in the discordant group with highest risk, whereas apoB was highest in the discordant group with the highest risk and lowest in the discordant group with the lowest group. Moreover, no significant change was found in the odds ratio for either discordant group when adjusted for the effect of any of the variables examined, evidence that none confounded the primary comparison.

Conclusion

Factors such as hypertriglyceridemia do not confound the comparison of apoB and non-HDL-C, further evidence that apoB is superior to non-HDL-C as a marker of the importance of the apoB atherogenic lipoproteins in cardiovascular risk.

 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility