The combined effect of pravastatin and aspirin on clinical cardiovascular events

The 3-hydroxy-3methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, or statins, can achieve significant reductions in plasma low-density lipoprotein (LDL)-cholesterol levels. Experimental and clinical evidence now shows that some statins interfere with formation of atherosclerotic lesions independent of their hypolipidemic properties. Vulnerable plaque rupture can result in thrombus formation and artery occlusion; this plaque deterioration is responsible for most acute coronary syndromes, including myocardial infarction (MI), unstable angina, and coronary death, as well as coronary heart diseaseequivalent non-hemorrhagic stroke. Inhibition of HMG-CoA reductase has potential pleiotropic effects other than lipid-lowering, as statins block mevalonic acid production, a precursor to cholesterol and numerous other metabolites. Statins' beneficial effects on clinical events may also thus involve nonlipid-related mechanisms that modify endothelial function, inflammatory responses, plaque stability, and thrombus formation. Aspirin, routinely prescribed to post-MI patients as adjunct therapy, may potentiate statins beneficial effects, as aspirin does not compete metabolically with statins but acts similarly on atherosclerotic lesions. Common functions of both medications include inhibition of platelet activity and aggregation, reduction in atherosclerotic plaque macrophage cell count, and prevention of atherosclerotic vessel endothelial dysfunction. The Cholesterol and Recurrent Events (CARE) trial provides an ideal population in which to examine the combined effects of pravastatin and aspirin. Lipid levels, intermediate outcomes, are examined by pravastatin and aspirin status, and differences between the two pravastatin groups are found. A modified Cox proportional-hazards model with aspirin as a time-dependent covariate was used to determine the effect of aspirin and pravastatin on the clinical cardiovascular composite endpoint of coronary heart disease death, recurrent MI or stroke. Among those assigned to pravastatin, use of aspirin reduced the composite primary endpoint by 35%; this result was similar by gender, race, and diabetic status. Older patients demonstrated a nonsignificant 21% reduction in the primary outcome, whereas the younger had a significant reduction of 43% in the composite primary outcome. Secondary outcomes examined include coronary artery bypass graft (38% reduction), nonsurgical bypass, peripheral vascular disease, and unstable angina. Pravastatin and aspirin in a post-MI population was found to be a beneficial combination that seems to work through lipid and nonlipid, anti-inflammatory mechanisms. ^

Influenza vaccination as a primary or secondary prevention for cardiovascular diseases: A systematic review of the literature

Background: Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality worldwide. CVD mainly comprise of coronary heart disease and stroke and were ranked first and fourth respectively amongst leading causes of death in the United States. Influenza (flu) causes annual outbreaks and pandemics and is increasingly recognized as an important trigger for acute coronary syndromes and stroke. Influenza vaccination is an inexpensive and effective strategy for prevention of influenza related complications in high risk individuals. Though it is recommended for all CVD patients, Influenza vaccine is still used at suboptimal levels in these patients owing to prevailing controversy related to its effectiveness in preventing CVD. This review was undertaken to critically assess the effectiveness of influenza vaccination as a primary or secondary prevention method for CVD. ^ Methods: A systematic review was conducted using electronic databases OVID MEDLINE, PUBMED (National Library of Medicine), EMBASE, GOOGLE SCHOLAR and TRIP (Turning Research into Practice). The study search was limited to peer-reviewed articles published in English language from January 1970 through May 2012. The case control studies, cohort studies and randomized controlled trials related to influenza vaccination and CVD, with data on at least one of the outcomes were identified. In the review, only population-based epidemiologic studies in all ethnic groups and of either sex and with age limitation of 30 yrs or above, with clinical CVD outcomes of interest were included. ^ Results: Of the 16 studies (8 case control studies, 6 cohort studies and 2 randomized controlled trials) that met the inclusion criteria, 14 studies reported that there was a significant benefit in u influenza vaccination as primary or secondary prevention method for preventing new cardiovascular events. In contrary to the above findings, two studies mentioned that there was no significant benefit of vaccination in CVD prevention. ^ Conclusion: The available body of evidence in the review elucidates that vaccination against influenza is associated with reduction in the risk of new CVD events, hospitalization for coronary heart disease and stroke and as well as the risk of death. The study findings disclose that the influenza vaccination is very effective in CVD prevention and should be encouraged for the high risk population. However, larger and more future studies like randomized control trials are needed to further evaluate and confirm these findings. ^