Intima media thickness

Inverse association. + = Positive association. 0 = No association. CHD = coronary heart disease. CVD = cardiovascular disease. Ml = myocardial infarction. IMT = intima media thickness. CCA-IMT = common carotid artery intima media thickness. LDL = low-density lipoprotein. 

Carotenoids and cardiovascular diseases — Numerous epidemiological studies aimed to study the relationship of carotenoids and cardiovascular diseases (CVDs) including coronary accident risk and stroke. It appeared then that observational studies, namely prospective and case-control studies, pointed to a protective effect of carotenoids on myocardial infarct and stroke, but also on some atherosclerosis markers such as intima media thickness (IMT) of the common carotid artery (CCA) and atheromatous plaque formation. 

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. 

Only fragmentary information exists in the human. In a study on 27 postmenopausal women with breast cancer, tamoxifen slightly slowed the progression of atherosclerosis as assessed by changes in carotid intima-media thickness (Stamatelopoulos et al. 2004). 

Stamatelopoulos KS, Lekakis JP, Poulakaki NA, Papamichael CM, Venetsanou K, Az-naouridis K, Protogerou AD, Papaioannou TG, Kumar S, Stamatelopoulos SF (2004) Tamoxifen improves endothelial function and reduces carotid intima-media thickness in postmenopausal women. Am Heart J 147 1093-1099... 

Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Research Group Intensive diabetes therapy and carotid intima-media thickness in type 1 diabetes mellitus. N Engl 3 Med 2003 348 2294. 

Heterozygous carriers of functionally relevant mutations usually present with HDL cholesterol levels that are frequently below the fifth percentile. As would be expected, apoA-I levels are also frequently below the fifth percentile (i.e., < 1.05 g/1 and < 1.1 g/1 in Caucasian men and women, respectively). In most cases, heterozygous carriers of apoA-I variants do not present with specific clinical symptoms. An important exception are some structural apoA-I variants with amino acid substitutions in the amino terminus, which have been detected in patients with familial amyloidosis of the liver, the intestine, the kidney, the heart, peripheral nerves, and in the skin. In addition, some apoA-I variants like apoA-I L178P or L159P have been associated with increased risk of premature coronary heart disease or enhanced progression of carotid intima media thickness, whereas others did not show this association, or were even claimed to have reduced cardiovascular risk and advocated as possible agents for the treatment or prevention of atherosclerosis (notably apoA-I R173CMiiano) [22,43,53]. 

Calao A, Di Somma C, Rota F, Di Maio S, Salerno M, Klain A, Spiezia S, Lombardi G. Common carotid intima-media thickness in growth hormone (GH) deficient adolescents a prospective study after GH withdrawal and restarting GH replacement. J Clin Endocrinol Metab 2005 90 2659-65. 

The Effect of Pomegranate Juice on Carotid Intima Media Thickness (1MT) and on End Diastolic Velocity (EDV) in Carotid Artery Stenosis (CAS) Patients... 

Aviram, M. et al., Pomegranate juice consumption for 3 years by patients with carotid artery stenosis reduces common carotid intima-media thickness, blood pressure and LDL oxidation, Clin. Nutr., 23,423, 2004. 

Balk EM, Lichtenstein AH, Chung M, Kupelnick B, Chew R Lau J. Effects of omega-3 fatty acids on coronary restenosis, intima-media thickness, and exercise tolerance a systematic review. Atherosclerosis 2006 184 237-246. 

Intensive diabetes therapy and carotid intima-media thickness in type I diabetes mellitus. 

Rubba P, Mercuri M, Faccenda F et al. (1994). Premature carotid atherosclerosis does it occur in both familial hypercholesterolemia and homocystinuria Ultrasound assessment of arterial intima-media thickness and blood flow velocity. Stroke 25 943-950 Rubinstein SM, Peerdeman SM, van Tulder MW et al. (2005). A systematic review of the risk factors for cervical artery dissection. Stroke 36 1575-1580... 

Cao, H. et al. Lack of association between carotid intima-media thickness and paraoxonase gene polymorphism in non-insulin dependent diabetes mellitus. Atherosclerosis 138... 

Fortunate, G. et al. A paraoxonase gene polymorphism, PON 1 (55), as an independent risk factor for increased carotid intima-media thickness in middle-aged women. Atherosclerosis 167 (2003) 141-8. 

Discuss the effect of statins (e.g., pravastatin, lovastatin) on carotid artery intima media thickness. 

This class of drugs has been shown to significantly reduce intima media thickness with long-term therapy. Incidence of stroke, cardiovascular events, and mortality are correspondingly decreased. 

Rissanen T, VoutUainen S, Nyyssonen K, Salonen R, Salonen JT. Low plasma lycopene concentration is associated with increased intima-media thickness of the carotid artery wall. Arterioscler Thromb Vase Biol 2000 20 2677-2681. 

Hanefeld M, Chiasson JL, Koehler C et al. Acarbose slows progression of intima-media thickness of the carotid arteries in subjects with impaired glucose tolerance. Stroke 2004 35(5) 1073-1078. 

Mazzone T, Meyer PM, Eeinstein SB, et al. Effect of pioglitazone compared with glimepiride on carotid intima-media thickness in type 2 diabetes. JAMA. 2006 296 2572-2581. 

Kiinzli et al. (2005) were the first to report an association of an indicator of atherosclerosis with PM2.5. They used data on 798 participants from two clinical trials to investigate the association between atherosclerosis and long-term exposure to ambient PM2.5. For a cross-sectional exposure contrast of 10 pg/m PM2.5, the atherosclerosis indicator used in the study (carotid intima-media thickness or CIMT) increased by 5.9% (95% Cl 1-11%). Several recent studies showed comparable results with other indicators of atherosclerosis (Diez Roux et al. 2008 Hoffmann et al. 2007). 

Vukusich A, Kunstmaim S, Varela C, Gainza D, Bravo S, Sepulveda D, Cavada G, Michea L, Marusic ET. A randomized, double-blind, placebo-controlled trial of spironolactone on carotid intima-media thickness in nondiabetic hemodialysis patients. Clin J Am Soc Nephrol 2010 5(8) 1380-7. 

Weissman NJ, Turco M. Extended-release niacin or ezetimibe and carotid intima-media thickness. N Engl J Med 2009 361 2113-22. 

Another important observation derived from RCTs was the unexpected association of B vitamins with increased cardiovascular risk. Evidence suggests an interaction between folic acid and baseline Hey, with potential harmful effects in patients with plasma Hey >12 rmol/F. Although there is no clear explanation of these findings, it can be hypothesized that B vitamins may in some way induce proatherogenic pathways by Hcy-independent mechanisms (Figure 3.1). Despite these experimental data, it remains questionable whether B vitamins administration can adversely affect plaque progression since clinical studies have reported beneficial or at least neutral effects of B vitamins on carotoid intima-media thickness (cIMT). However, other data (Fange et al. 2004),... 

Durga, J., Bots, M.L., Schouten, E.G., Grobbee, D.E., Kok, F.J., and Verhoef, P., 2011. Effect of 3 y of folic acid supplementation on the progression of carotid intima-media thickness and carotid arterial stiffness in older adultsl,3. American Journal of Clinical Nutrition. 93 941-949. 

Potter, K., Hankey, G.J., Green, D.J., Eikelboom, J., Jamrozik, K., and Arnolda, L.F., 2008. The effect of long-term homocysteine-lowering on carotid intima-media thickness and flow-mediated vasodilation in stroke patients a randomized controlled trial and meta-analysis. BMC Cardiovascular Disorders. 8 24. 

There is increasing evidence that niacin has potential benefit in decreasing inflammation, an important part of atherosclerosis. This may be mediated in part by ability of niacin to increase HDL or direct anti-inflammatory effect independent of the HDL (Vaccari et al. 2007a,b). For instance, administration of extended-release niacin (1000 mg/day) in 52 individuals with the metabolic syndrome was shown to be associated with a marked change of carotid intima-media thickness (IMT), improvement of endothelial function and decrease in high sensitivity C-reactive protein (Thoenes et al. 2007). 

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