Plasma homocysteine and S-adenosylmethionine in erythrocytes as determinants of carotid intima-media thickness: different effects in diabetic and non-diabetic individuals : The Hoorn Study

• Published in: Atherosclerosis Vol. 169; no. 2; pp. 323 - 330
• Main Authors: Becker, A, Henry, R.M.A, Kostense, P.J, Jakobs, C, Teerlink, T, Zweegman, S, Dekker, J.M, Nijpels, G, Heine, R.J, Bouter, L.M, Smulders, Y.M, Stehouwer, C.D.A
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ireland Ltd 01.08.2003; Elsevier
• Subjects: Aged; Arteriosclerosis - pathology; Atherosclerosis; Atherosclerosis (general aspects, experimental research); Biological and medical sciences; Blood and lymphatic vessels; Cardiology. Vascular system; Carotid Arteries - pathology; Cross-Sectional Studies; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - pathology; Erythrocytes - chemistry; Female; Homocysteine; Homocysteine - blood; Humans; Intima-media thickness; Male; Medical sciences; Middle Aged; S-adenosylmethionine; S-Adenosylmethionine - blood; Tunica Intima - pathology; Tunica Media - pathology; Type 2 diabetes; Vitamin B 12 - blood; Vitamin B 6 - blood; Type 2 diabetes; Intima-media thickness; Homocysteine; S-adenosylmethionine; Atherosclerosis; Endocrinopathy; Human; Thiol; Adenosylmethionine; Diabetes mellitus; Media; Red blood cell; Clinical form; Cardiovascular disease; Blood plasma; Vascular disease; Sulfur containing aminoacid; Homocystein; Carotid; Risk factor; Intima
• ISSN: 0021-9150; 1879-1484
• DOI: 10.1016/S0021-9150(03)00199-0

Objective: Hyperhomocysteinemia is a risk factor for atherothrombosis. Through unknown mechanisms, individuals with type 2 diabetes appear particularly susceptible. We determined whether components of homocysteine metabolism are associated with intima-media thickness in individuals with and without type 2 diabetes. Methods and results: In a cross-sectional design, we studied 231 Caucasian individuals, 60.6% having type 2 diabetes. We measured fasting homocysteine, vitamin B 6 and vitamin B 12 in plasma, and folate, S-adenosylmethionine and S-adenosylhomocysteine in plasma and erythrocytes. A homocysteine concentration >12 μmol/l was associated with a greater intima-media thickness of +0.07 mm (95% CI, +0.01 to +0.13; P=0.03) among diabetic individuals and of −0.004 mm (95%CI, −0.08 to +0.07; P=0.92) among non-diabetic individuals. An erythrocyte S-adenosylmethionine concentration above >4000 nmol/l was associated with a smaller intima-media thickness of −0.04 mm (95%CI, −0.10 to +0.02; P=0.17) for diabetic individuals versus −0.12 mm (95%CI, −0.20 to −0.36; P=0.005) for non-diabetic individuals. Conclusions: With regard to carotid intima-media thickness, individuals with diabetes appear more susceptible to the detrimental effects of homocysteine than non-diabetic individuals. In addition, diabetic individuals may lack the protective effect on the vascular wall conferred by high concentrations of S-adenosylmethionine. These findings may help explain why hyperhomocysteinemia is an especially strong risk factor for atherothrombosis among individuals with type 2 diabetes.