Relation between Homocysteine, hs-CRP, Osteoprotegerin, Fetuin-A and thickness of carotis intima media in type 2 diabetic patients with or without nephropathy

Cardiovascular disease risk at a diabetic patient increases significantly when nephropathy complication is developed in addition to endothelial dysfunction. In recent years, vascular calcification is defined as an active process with its activators and inhibitors, on lieu of a passive definition. The most recent studies focus on the effects of osteoprotegerin (OPG) and fetuin-A levels on vascular calsification, atherosclerosis and coronary artery disease. At this study; data of OPG and fetuin-A levels of patients that are grouped according to nephropathy variable at diabetic individuals are obtained. In addition to the obtained data hs-CRP (high sensitivity- CRP) level which have a controversial role at atherosclerosis and homocysteine level that is accepted as a proinflamatory marker are studied. The correlations in between the 4 variables and the correlation of these 4 variables with average carotis intima media thickness (CIMT) are identified. 4 groups, each including 40 individuals, are defined for the study. The 4 groups? individuals show the following attributes respectively: Normoalbuminuric diabetic patients, microalbuminuric diabetic patients, macroalbuminuric diabetic patients, and healty individuals as the control group. All of the groups are evaluated according to the OPG, fetuin-A, homosistein, hs-CRP and CIMT variables. The correlations of these five variables are investigated in terms of each individual group and in the groups of diabetic patients with (group 2 + group 3) and without nephropathy (group 1). As a result the positive correlation between fetuin-A and OPG (p=0.012, r=0.393) in group 1, the positive correlation between fetuin-A and hs-CRP (p=0.020, r=0.367) in group 2, the negative correlation between hs-CRP and OPG (p=0.036, r=-0.333) in group 3, the positive correlation between fetuin-A and homocysteine (p=0.048, r= 0.315) in group 4 and the negative correlation between homocysteine and OPG (p=0.048, r=-0.222) in nephropatic group are found. Further investigation about the relationship between these five variables is needed.In the study; although increased serum levels of homocysteine, hs-CRP and measurements of CIMT are found in nephropathic diabetic patients (group 2+3) compared with normoalbuminuric diabetic (group 1) patients; statistically meaningful difference of serum levels of fetuin-A and OPG in these two groups could not be found. Statistically meaningful correlation is also not found between albuminuria and OPG, hs-CRP, fetuin-A for type-2 diabetic patients. At the microalbuminic group (group 2), statistically meaningful correlation (p=0.011, r=0.397) between albuminuria and homocysteine level is concluded. At group 3 (macroalbuminuric diabetic group) statistically meaningful correlation (p=0.000, r=0.577) between albuminuria and CIMT is also reached. This result clearly exhibits the atherosclerosis-albuminuria correlation. The reason behind the results found between OPG and albuminuria or fetuin-A and albuminuria, may be the the different doses and variety of medication the patients are using in addition to genetic and race factors. So far, in our country; polymorfism related with OPG and fetuin-A has not been defined. Further detailed studies about this issue is needed.Key Words: OPG, fetuin-A, hs-CRP, homocysteine, CIMT.