Hemoglobin A1c and retinal arteriolar narrowing in children with type 1 diabetes: the diagnostics of early atherosclerosis risk in kids study.

BACKGROUND/OBJECTIVE: Microvascular alterations play a key role in the development of diabetes complications. Retinal vessel analysis is a unique method to examine microvascular changes in brain-derived vessels. METHODS: Sixty-seven pediatric and adolescent type 1 diabetes patients and 58 healthy control persons (mean age 12.4 ± 2.9 years) underwent non-mydriatic retinal photography of both eyes. Central retinal arteriolar and central retinal venular (CRVE) diameter equivalents as well as the arteriolar-to-venular ratio were calculated using a semiautomated software. All anthropometric and laboratory parameters were measured according to standardized procedures for children. RESULTS: Retinal vessel diameter did not differ between type 1 diabetic children and healthy controls. However, there was an independent association of higher hemoglobin A1c (HbA1c) levels with arteriolar narrowing. Arteriolar narrowing of 5.4 µm was observed with each percent increase in HbA1c. Longer duration of diabetes was associated with wider retinal arterioles. CRVE was not associated with diabetes duration or HbA1c. CONCLUSIONS: Microvascular arteriolar alterations are already present in childhood and may indicate subclinical atherosclerosis and increased risk of diabetes complications later in life. Future research will have to investigate the potential use of retinal vessel diameters for treatment monitoring and guidance of therapy in children.

Marked smoking-associated increase of cardiovascular risk in childhood type 1 diabetes.

Type 1 diabetes is a generally accepted atherogenic risk factor, and diabetic patients who smoke markedly accelerate the atherosclerotic process. The main intentions of our investigation were to ascertain differences between juvenile active/passive smokers and non-smokers with type 1 diabetes regarding the number and spectrum of cardiovascular risk factors and their associations with smoking. Ninety-two patients were enrolled comprising 19 active/passive smokers (median age 15.9 years) and 73 non-smokers (median age 12.3 years). To determine age-dependent influences we compared age- and gender-matched groups of 12 smokers with 12 non-smokers. Smokers had significantly higher HbA1c, fructosamine, total cholesterol, LDL cholesterol, apolipoprotein B, serum P-selectin, and lower serum L-selectin than non-smokers. However, L-selectin levels were not different between the age-matched smoker and non-smoker groups. A significant positive relation (Spearman rank correlation) was found between smoking and age, HbAlc, fructosamine, total cholesterol, apolipoprotein B, and P-selectin; a negative relationship between smoking and L-selectin. We conclude that smoking in children and adolescents with type 1 diabetes increases the cardiovascular risk through the deterioration of glucose metabolism, lipid profile, and endothelial function. Therefore, smoking diabetic juveniles may increase their number of cardiovascular risk factors from 1, diabetes, by another four factors, i.e. smoking, hyperglycemia, dyslipidemia, and endothelial perturbation.

Early atherosclerosis in childhood type 1 diabetes: role of raised systolic blood pressure in the absence of dyslipidaemia.

The intentions of our investigation were (1) to search for atherogenic risk factors and signs of incipient atherosclerosis in children and adolescents with type 1 diabetes (T1DM) in comparison to well-matched control subjects, (2) to evaluate risk factor associations with carotid intima media thickness (cIMT) in diabetic patients and control subjects, and (3) to acquire a better knowledge of early atherogenesis in children and adolescents with and without T1DM. 94 diabetic children (age median 12.3 years, HbA1c median 7.7%) and 40 non-diabetic controls (age median 12.3 years) were investigated. Mean cIMT was determined using high-resolution B-mode ultrasound with an automated contour identification procedure. Compared to controls, subjects with diabetes had significantly elevated cIMT (p = 0.041) and systolic BP (p = 0.007) but showed a less atherogenic lipid profile. Most markers of inflammation, endothelial function and fibrinolytic activity were higher in diabetic subjects than in controls. Multiple linear regression analysis revealed a significant relationship (r = 0.53, p = 0.036) between bilateral mean cIMT and diverse risk factors in patients with T1DM. Spearman rank correlation showed that diabetes duration (rho = 0.32, p = 0.029), systolic BP (rho = 0.32, p = 0.004), weight (rho = 0.257, p = 0.022), and height (rho = 0.265, p = 0.018) significantly correlated with bilateral mean cIMT in the 94 diabetic patients. In conclusion, in well-controlled type 1 diabetic children systolic BP may be of greater importance than dyslipidaemia in early atherogenesis. BMI, markers of sustained inflammation, endothelial dysfunction and fibrinolytic activity are increased in diabetic versus non-diabetic children but none of them correlates significantly with cIMT. Their prognostic value remains to be determined.