Atherosclerosis study

Some prospective and case-control studies also investigated the relationship of carotenoids and the evolution of CCA-IMT. Although the EVA study showed no association between total carotenoids and IMT, others like the ARIC study, the Los Angeles Atherosclerosis Study, " and the Kuopio Ischaemic Heart Disease Risk Factor Study demonstrated the protective role of isolated carotenoids such as lycopene, lutein, zeaxanthin, and P-cryptoxanthin on IMT. Thus, findings from prospective and case-control studies have suggested that some carotenoids such as lycopene and P-carotene may present protective effects against CVD and particularly myocardial infarcts and intima media thickness, a marker of atherosclerosis. 

Dwyer, J.H. et al., Oxygenated carotenoid lutein and progression of early atherosclerosis the Los Angeles atherosclerosis study, Circulation, 103, 292, 2001. 

Bjarnason NH, Haarbo J, Byrjalsen I, Kauffman RF, Knadler MP, Christiansen C (2000) Raloxifene reduces atherosclerosis studies of optimized raloxifene doses in ovariectomized, cholesterol-fed rabbits. Clin Endocrinol 52 225-233... 

Festa A, D Agostino R, Jr, Howard G, Mykkanen L, Tracy RP, Haffner SM. Chronic subclinical inflammation as part of the insulin resistance syndrome The Insulin Resistance Atherosclerosis Study (IRAS). Circulation 2000 102 42-47. 

Endarterectomy for asymptomatic carotid artery stenosis. Executive Committee for the Asymptomatic Carotid Atherosclerosis Study. JAMA 1995 273 1421-1428. 

Baker WH, Howard VJ, Howard G, Toole JF Effect of contralateral occlusion on long-term efficacy of endarterectomy in the asymptomatic carotid atherosclerosis study (ACAS), ACAS Investigators. Stroke 2000 3 1 2330—2334. 

Blaton V, Peeters H (1976) The nonhuman primates as models for studying atherosclerosis Studies on the chimpanzee, the baboon and the rhesus macacus. In Day CE (ed) Atherosclerosis Drug Discovery. Plenum Press, New York, London, pp 33-64... 

How centers and clinicians were selected to participate in trials is seldom reported, but it can also have important implications for external validity. For example, the Asymptomatic Carotid Atherosclerosis Study (ACAS) trial of endarterectomy for asymptomatic carotid stenosis only accepted surgeons with an excellent safety record, rejecting 40% of applicants initially, and subsequently barring from further participation those who had adverse operative outcomes in the trial. The benefit from surgery in the trial was a result in major... 

Asymptomatic Carotid Atherosclerosis Study Group (1995). Carotid endarterectomy for patients with asymptomatic internal carotid artery stenosis. Journal of the American Medical Association 273 1421-1428 Barnett HJ, Taylor DW, Ehasziw M etal. (1998). The final results of the NASCET trial. New England Journal of Medicine 339 1415-1425 Cardiac Arrhythmia Suppression Trial (CAST) Investigators (1989). Preliminary report effect of encainide and flecainide on mortality in a randomised trial of arrhythmia suppression after myocardial infarction. New England Journal of Medicine 321 406-412 Charleson ME, Horwitz RI (1984). Applying results of randomised trials to clinical practice impact of losses before randomisation. British Medical Journal 289 1281-1284... 

Fig. 28.2. The overall results of a meta-analysis of the operative risk of death (a) and stroke and death (b) from all studies published between 1990 and 2000 inclusive that reported risks from carotid endarterectomy for asymptomatic stenosis (Bond et ai. 2003a) compared with the same risks in the ACAS Trial (Executive Committee for the Asymptomatic Carotid Atherosclerosis Study 1995). Studies in the analysis of risk of stroke and death are...

Fig, 28.3. The effect of endarterectomy for asymptomatic carotid stenosis on the risk of any stroke and operative death by sex (Rothwell 2004) in the /ksymptomatic Carotid Surgery Trial (ACST Halliday ef al. 2004) and the AC/ S Trial (Executive Committee for the Asymptomatic Carotid Atherosclerosis Study 1995). Cl, confidence interval. 

The ACAS reported a statistically borderline sex-treatment effect interaction, with no benefit from endarterectomy in women (Executive Committee for the Asymptomatic Carotid Atherosclerosis Study 1995). The same trend was seen in ACST (Halliday et al. 2004). A meta-analysis of the effect of endarterectomy on the five-year risk of any stroke and perioperative death in ACAS and ACST (Rothwell 2004) (Fig. 28.3) showed that benefit from surgery was greater in men than in women (pooled interaction, p = 0.01), and that it remained uncertain whether there is any worthwhile benefit in women at five years of follow-up, although some benefit may accrue with longer follow-up in ACST. 

Borhani NO, Mercuri M, Borhani PA, Buckalew VM, Canossa-Terris M, Carr AA, Kappagoda T, Rocco MV, Schnaper HW, Sowers JR, Bond MG. Final outcome results of the Multicenter Isradipine Diuretic Atherosclerosis Study (MIDAS). A randomized controlled trial. JAMA 1996 276(10) 785-91. 

Qarke SC, Kelleher J, Lloyd-Jones H, et al. A study of hormone replacement therapy in postmenopausal women with ischaemic heart disease The Papworth HRT Atherosclerosis Study. Br J Obstet Gynaecol 2002 109 1056-1062. 

The incidence of cardiovascular disease is low in premenopausal women, rising rapidly after menopause, and epidemiological studies consistently showed an association between estrogen use and reduced cardiovascular disease in postmenopausal women. Furthermore, estrogens produce a favorable lipoprotein profile, promote vasodilation, inhibit the response to vascular injury, and reduce atherosclerosis. Studies such as these led to the widespread use of estrogen for prevention of cardiovascular disease in postmenopausal women. 

MRA of neck vessels is important in stroke management because extracranial atherosclerosis causes an estimated 20-30% of strokes. The NASCET trial demonstrated that carotid endarterectomy improves survival in symptomatic patients with carotid stenosis of 70-99% [35]. The Asymptomatic Carotid Atherosclerosis Study also suggested that asymptomatic patients with a stenosis of 60% could benefit from endarterectomy [36]. Since then, multiple studies have evaluated the ability of contrast-enhanced and noncontrast MRA to distinguish between nonsurgical (<70%) and surgical stenoses (70-99%). 

Chen, S., N. Tsybouleva, C.M. Ballantyne, A.M. Gotto, Jr., and A.J. Marian. EflFects of PPARa, y and 5 Haplotypes on Plasma Levels of Lipids, Severity and Progression of Coronary Atherosclerosis and Response to Statin Therapy in the Lipoprotein Coronary Atherosclerosis Study, 14 61-71 (2004). 

Carlson and Rosenhamer 1988) Cholesterol Lowering Atherosclerosis Study (CLAS) (Blankenhom et al. 1987) Familial Atherosclerosis Treatment Study (FATS) (Brown et al. 1990)... 

In order to Illustrate the different effects of carbohydrates in different species in atherosclerosis studies, one investigation with... 

These studies suggest the importance of TG-rich lipoprotein reduction and HDL raising for the retardation of atherosclerosis in mild to moderate lesions, and a role for fibric acid derivatives in secondary prevention. Analysis of data from Cholesterol Lowering Atherosclerosis Study (CLAS), the Program on the Surgical Control of Hyperlipidemias (POSCH), and MARS studies also provide evidence for the importance of TG rich lipoprotein in progression of CAD. 

LDL-C is known to cause numerous cellular changes that contribute to the atherosclerotic process through the subendothelial retention of Apo B 100 containing lipoproteins, followed by biologic responses to the retained material (reviewed in ref. 347). One of the first alterations in EC function induced by LDL-C is an attenuation of endothelial-dependent vasodilation. This reduced responsiveness to vasodilation occurs before any clinical evidence of atherosclerosis. Studies in isolated vessels from normal animals demonstrate a reduction in endothelial-dependent vasodilation within minutes of exposure to oxLDL (348,349). 

Dwyer KM, Nordstrom CK, Bairey Merz CN, Dwyer JH. Carotid wall thickness and years since bilateral oophorectomy the Los Angeles Atherosclerosis Study. Am J Epidemiol 2002 156 438-444. 

HPJ Buschman, TJ Romer, ML Wach, ET Marple, A van der Laarse, AVG Bruschke, GJ Puppels. Human coronary atherosclerosis studied in vitro by catheter-based transluminal Raman spectroscopy. Proc. SPIE 3608 12-17, 1999. 

Iodine. The sole function of iodine in the human body is as a component of the hormones secreted by the thyroid gland. A dietary deficiency of iodine may lead to low levels of these hormones (hypothyroidism), a condition which is often accompanied by high blood cholesterol, and in some cases, atherosclerosis. Studies in Finland have shown that, although the dietary levels of fat are similar throughout the country, there seem to be more cases of cardiovascular diseases in the areas where the rates of goiter (an enlargement of the thyroid due to iodine deficiency) are also high. ... 

Inter-Society Commission for Heart Disease Resources. Atherosclerosis Study Group and Epidemiology Study Group. Primary Prevention of the Atherosclerotic Diseases. Circulation, A55, 1970. 

The classification into different types of human hyperlipopro-teinaemias was the main argument of a Course which was held, last year, in this same Institute and before that in Milan (47). It is performed in our country by the Italian Society of Atherosclerosis Studies, and its President, Prof. Paoletti. The typing permits the differential diagnosis of the various forms on a genetic basis, it gives the possibility of identifying other alterations which may induce atherosclerosis and to identify action mechanisms, and allows adequate and specific treatments. We cannot, today, be satisfied with overall solutions. 

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