Asymmetric dimethylarginine levels in Buerger's disease.

Background: Endothelial dysfunction may play a major role in both peripheral arterial disease (PAD) and Buerger's disease (BD). Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide synthase and increased ADMA levels impair vascular homeostasis. We aimed to determine the plasma levels of ADMA and evaluate the relationship of ADMA levels with smoking and clinical severity of the disease in patients with BD and to compare these results with those of patients with PAD and healthy individuals.

Methods: In our center, 45 patients undergoing peripheral arterial surgery, 28 patients being followed up for BD, and 24 healthy individuals without vascular or cardiac disease, were enrolled in the study. Intra- and intergroup analysis was performed to evaluate the relationship of ADMA levels with smoking behaviors and clinical disease severity according to Fontaine classification.

Results: ADMA levels were 1.26 ± 0.76 mmol/L, 0.87 ± 0.27 mmol/L, and 1.07 ± 0.88 mmol/L in patients with PAD, in patients with BD, and in the control group, respectively. ADMA levels were significantly higher in patients with PAD than those in control patients (p = 0.003) and the levels observed in patients with BD were significantly lower than those in control patients (p = 0.001). Smokers with PAD had higher ADMA levels than smokers with BD (p = 0.03). ADMA levels were higher in patients with Fontaine stage III and IV disease than those with Fontaine stage II diseases, for patients with PAD as well as those with BD.

Conclusion: The lower ADMA levels observed in patients with BD might be related to the degradation of ADMA by dimethylarginine dimethylaminohydrolase in response to ischemia and could act as a defensive mechanism during the acute or quiescent phases. In patients with BD experiencing severe clinical conditions or with a longer time course for the disease, higher ADMA levels may suggest a poor prognosis.