The aims of this study are to describe the mean values of carotid intima-media thickness and how it increases with age, and to compare carotid injury in diabetics and hypertensive patients with that of controls. We included 562 subjects (121 diabetics, 352 hypertensive patients, 89 controls). The mean intima-media thickness was 0.781 mm in diabetics, 0.738 mm in hypertensive patients and 0.686 mm in controls. The difference in intima-media thickness between diabetics and controls and between hypertensive patients and controls, adjusted for age, was 0.040 and 0.026 mm, respectively. We observed an increase in intima-media thickness of 0.005 mm in diabetics and of 0.005 mm in controls with every additional year of age. We found carotid damage in 23% of the diabetics, 12% of the hypertensive patients and 3.4% of the controls. In conclusion, the intima-media thickness is greater in diabetics, but the annual increase in the thickness is greater in hypertensive patients. Full English text available from:www.revespcardiol.org.