White blood cell count predicts reduction in coronary heart disease mortality with pravastatin.

Abstract

BACKGROUND:

Elevated serum inflammatory marker levels are associated with a greater long-term risk of cardiovascular events. Because 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitors (statins) may have an antiinflammatory action, it has been suggested that patients with elevated inflammatory marker levels may have a greater reduction in cardiovascular risk with statin treatment.

METHODS AND RESULTS:

We evaluated the association between the white blood cell count (WBC) and coronary heart disease mortality during a mean follow-up of 6.0 years in the Long-Term Intervention With Pravastatin in Ischemic Disease (LIPID) Study, a clinical trial comparing pravastatin (40 mg/d) with a placebo in 9014 stable patients with previous myocardial infarction or unstable angina. An increase in baseline WBC was associated with greater coronary heart disease mortality in patients randomized to placebo (hazard ratio for 1x10(9)/L increase in WBC, 1.18; 95% CI, 1.12 to 1.25; P<0.001) but not pravastatin (hazard ratio, 1.02; 95% CI, 0.96 to 1.09; P=0.56; P for interaction=0.004). The numbers of coronary heart disease deaths prevented per 1000 patients treated with pravastatin were 0, 9, 30, and 38 for baseline WBC quartiles of <5.9, 6.0 to 6.9, 7.0 to 8.1, and >8.2x10(9)/L, respectively. WBC was a stronger predictor of this treatment benefit than the ratio of total to high-density lipoprotein cholesterol and a global measure of cardiac risk. There was also a greater reduction (P=0.052) in the combined incidence of cardiovascular mortality, nonfatal myocardial infarction, and stroke with pravastatin as baseline WBC increased (by quartile: 3, 41, 61, and 60 events prevented per 1000 patients treated, respectively).

CONCLUSIONS:

These data support the hypothesis that individuals with evidence of inflammation may obtain a greater benefit from statin therapy.

• Authors: Ralph A H Stewart, Harvey D White, Adrienne C Kirby, Stephane R Heritier, R John Simes, Paul J Nestel, Malcolm J West, David M Colquhoun, Andrew M Tonkin, Long-Term Intervention With Pravastatin in Ischemic Disease (LIPID) Study Investigators
• Journal: Circulation (Circulation) Vol. 111 Issue 14 Pg. 1756-62 (Apr 12 2005) ISSN: 1524-4539 [Electronic] United States
• PMID: 15809366 (Publication Type: Clinical Trial, Journal Article, Multicenter Study, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers
• Pravastatin

Topics

• Aged
• Biomarkers (blood)
• Coronary Disease (drug therapy, mortality)
• Female
• Humans
• Inflammation (diagnosis, drug therapy)
• Leukocyte Count
• Male
• Middle Aged
• Myocardial Infarction (prevention & control)
• Pravastatin (administration & dosage)
• Predictive Value of Tests
• Prognosis
• Stroke (prevention & control)
• Survival Rate