Serum homocysteine levels were examined in a 24-hour study of 7 healthy and
5 diabetic men, revealing a statistically significant circadian rhythm (p
= 0.030), normal concentrations of 11.83 1.2 vs 12.99 +/- 1.2 mu mol/L, wit
h peak values occurring during the evening (10:37 P.M.) and lowest levels o
ccurring during the morning. These findings imply that increased atheroscle
rotic risk in insulin-resistant diabetics during morning hours does not app
ear to be explained by differences in homocysteine levels in the normal pop
ulation.