[Clinical relevance of homocysteine monitoring in the diabetic patient]. / Faut-il doser l'homocystéine chez le patient diabétique?

Accelerated atherosclerosis is common in diabetes mellitus, although its extent is not always related to its strong association with classical cardiovascular risk factors. Diabetic patients, especially with type 2 diabetes, are prone to cardiovascular disease which is the leading cause of death in this population. Recent clinical studies among general population have shown that an even mild increase of homocysteinemia play an important role in the progression of atherosclerosis, either in coronary or peripheral arteries. An increasing amount of in vitro data is providing evidence that excess of homocysteine has a toxic effect on the arterial wall. This aminoacid thus appears to be not only a risk marker but also an emerging cardiovascular risk factor. The measurement of plasma homocysteine contributes to the identification, among the diabetic population, of patients at high cardio-vascular risk, with the aim of improving their global management. Moreover the addition of group B vitamins provides an easy and low-cost treatment to lower hyperhomocysteinemia.

Assessment of cardiac arrhythmic risk in diabetic patients using QT dispersion abnormalities.

The purpose of this study was to assess the abnormalities and prevalence of QT dispersion in 154 diabetic patients (DP) who underwent a standard 12-lead ECG. QT interval was measured from the beginning of the QRS complex until the T wave returned to baseline. Atrial fibrillation, pacemakers and the impossibility of measuring 6 QT intervals per ECG were reasons for exclusion from the study. Diabetic patients were compared with 104 sex- and age-matched controls (C): mean age 50.7 +/- 2.3 years (DP) vs 48.4 +/- 10.1 (C) (ns); diabetes duration: 11.6 +/- 7.9 years. Seventy-eight percent of DP were non-insulin-dependent. Mean QT duration was 0.383 +/- 0.031 s (DP) vs 0.381 +/- 0.026 (C) (ns); QT dispersion (difference between the longest and shortest QT interval measurement) 0.033 +/- 0.015 s (DP) vs 0.024 +/- 0.011 (C) (p < 0.001); and QT variability 3.003 +/- 1.23% (DP) vs 2.295 +/- 0.936 (C) (p < 0.001); with a standard deviation of 0.012 +/- 0.005 s (DP) vs 0.009 +/- 0.004 (C) (ns). QT dispersion indices (dispersion, variability) were significantly increased in DP, even for short diabetes duration. Future studies should focus on QT dispersion to assess the usefulness of such indices in detecting DP at high risk of sudden death and ventricular arrhythmias.