Type 2 diabetes mellitus (non insulin-dependent diabetes mellitus: NIDDM) is known to be associated with degenerative complications. Although, the pathophysiology of such complications is well known, the role of homocysteine (Hcy) is still discussed. The aim of the present study was to evaluate the relationship between the homocysteine levels and the NIDDM related complications in a group of NIDDM patients. Our study population consisted of 41 NIDDM patients including 13 subjects (G1) without complications (group controls), 17 patients (G2) with microangiopathy and 11 patients (G3) with coronary deficiency. Plasmatic homocysteine, glycemia, glycated haemoglobin (HbA1C) and lipidic parameters were essessed in all patients. Our results showed that mean levels of plasmatic homocysteine were within the normal range (10.4 +/- 3.3 micromol/l, 9.9 +/- 5.5 micromol/l and 14.8 +/- 10.4 micromol/l in G1, G2 and G3 respectively). Nevertheless, moderate hyperhomocysteinaemia was found in 36% in the coronary group (G3), 17.3% in patients with microangiopathy (G2) and 7.7% in controls. These preliminary results showed that cardiovascular complications in NIDDM patients may be related to high levels of homocysteine.