Mild hyperhomocysteinemia is associated with impaired renal function but not with progression of small abdominal aortic aneurysms

To study the possible role of homocysteine in aneurysmatic progression, in 1994, 112 of 141 male patients with abdominal aortic aneurysm (AAA) diagnosed by population screening were interviewed and examined. Creatinine clearance estimated and total plasma homocysteine (P-tHcy) was measured by gas chromatography-mass spectrometry. Of the 112 cases, 99 were followed with annual ultrasonography and blood pressure measurements for 1–5 years (mean 2.5 years). The mean creatinine clearance was 70.8+/-23.1 ml/min, while the mean P-tHcy was 16.0+/-10.6 mmol/l, significantly increased compared with an age- and sex-matched reference population (P<0.01). However, no trend of correlation with AAA size or aneurysmal progression was found concerning creatinine clearance and homocysteine level. There were still no trend after adjustment for age, smoking, diastolic blood pressure, and initial ankle blood pressure index. However, the homocysteine level was positively correlated with decreasing creatinine clearance (r=0.36,P<0.01), and this correlation was still present after the same adjustments. A large proportion of men with AAA have mild hyperhomocysteinemia; this does not influence aneurysmal progression and may be due to coexisting impaired renal function. The finding might explain why prospective and intervention studies cannot prove for certain that hyperhomocysteinemia influences atherosclerotic progression, or that treatment is beneficial.