SAN DIEGO – Adolescents and young adults with type 1 diabetes have thicker and stiffer carotid arteries, compared with their healthy peers, results from a multicenter study showed.
"Type 1 diabetes has an adverse effect on carotid thickness and stiffness, and we can measure this by the time patients reach young adulthood," Dr. Elaine M. Urbina said at the annual scientific sessions of the American Diabetes Association. "It’s independent of demographics, lipids, and blood pressure, but may be influenced by adiposity. We need to control risk factors, especially obesity, in these adolescents and young adults to improve cardiovascular outcomes in type 1 diabetes."
Dr. Elaine M. Urbina
As part of the SEARCH CVD study, a collaborative effort between investigators at the University of Colorado at Denver, the Colorado School of Public Health in Aurora, and Cincinnati Children’s Hospital Medical Center, Dr. Urbina and her associates set out to examine whether type 1 diabetes has a measurable effect on carotid arteries in adolescents and young adults. They studied 162 people aged 13-26 years, collecting data on demographics, anthropometrics, blood pressure, fasting lipid and hemoglobin A1c levels, and carotid ultrasound to measure the common, bulb, and internal carotid intima-media thickness (cIMT), with M-mode for calculation of carotid stiffness by Peterson’s elastic modulus (PEM), Young’s elastic modulus (YEM), and the incremental elastic modulus (Einc).
Of the 162 study participants, 127 (78%) had type 1 diabetes and 35 were healthy controls who attended clinics at the two locations, said Dr. Urbina, director of preventive cardiology at Cincinnati Children’s Hospital Medical Center. Their mean age was 20 years, 51% were male, 81% were white, and their mean duration of diabetes was 10 years.
Dr. Urbina reported that there were significantly higher proportions of males and whites among cases, compared with controls (55% vs. 34% and 90% vs. 50%, respectively), but there were no significant differences between the two groups in anthropometric or lipid values.
After adjustment for age, sex, race, mean arterial pressure by mercury sphygmomanometry, and lipids, patients with type 1 diabetes had a significantly thicker internal cIMT, compared with controls (mean, 0.56 mm vs. 0.50 mm, respectively), with a trend for a thicker common cIMT (mean, 0.63 mm vs. 0.60 mm). Bulb cIMT was the same in both groups (mean, 0.61 mm).
Patients with type 1 diabetes also had significantly stiffer carotids, compared with controls (mean PEM, 193 mm Hg vs. 169 mm Hg, respectively; mean YEM, 204 mm Hg/mm vs. 182 mm Hg/mm; mean Einc, 963 mm Hg vs. 862 mm Hg).
After adjustment for body mass index, there was a trend only for significantly thicker internal cIMT, although PEM remained stiffer for the patients with type 1 diabetes who were at least 20 years old.
SEARCH CVD is funded by the National Institutes of Health and is an ancillary study of the SEARCH for Diabetes in Youth study, a multicenter study funded by the Centers for Disease Control and Prevention and the National Institute of Diabetes and Digestive and Kidney Diseases.
Dr. Urbina said that she had no relevant financial disclosures to make.