Association of below-knee atherosclerosis to medial arterial calcification in diabetes mellitus.

In diabetes mellitus, peripheral arterial occlusive disease (PAOD) more often affects the lower rather than the upper leg. It is hypothesized that peripheral medial arterial calcification (MAC) may be related to this phenomenon. In 42 diabetic patients subjected to arteriography for PAOD, forefoot roentgenogrammes were also obtained for assessment of MAC, e.g. of the metatarsal arteries. The distribution of PAOD (number of partial and total arterial stenoses per leg) was assessed according to the coexistence of MAC. A total of 242 partial and complete stenoses was found in 35 MAC-positive legs and 28 MAC-negative legs. MAC-positive legs displayed 4 (3-6) stenoses per leg (median with 95% confidence interval), vs. 3 (2-5) stenoses per MAC-negative leg. MAC-positive legs had more than twice as many stenoses located in the lower (2.6 (2.3-2.8) stenoses below knee) as compared to the upper leg (1.3 (1.0-1.7) stenoses above knee; P < 0.05), whereas stenoses were equally distributed above and below the knee in MAC-negative legs. The prevalence of stenoses in the truncus tibiofibularis and in the foot arteries (e.g. arteria dorsalis pedis) was unaffected by MAC-status. In conclusion, the predominance of PAOD in the lower leg of diabetic patients appears to be related to the presence of forefoot medial arterial calcification. The underlying pathogenesis remains to be elucidated.