Inverse correlation between serum free IGF-I and IGFBP-3 levels and blood pressure in patients affected with type 1 diabetes

BACKGROUND: Even though the gene encoding for IGF-I is considered of most importance amongst blood pressure-regulating genes in mouse models, little and discordant data are available in literature for what concerns a possible relationship between blood pressure and serum free IGF-I values in humans. In addition, no information is available on type 1 diabetes patients. AIM: Our aim is to analyze the relationship between systolic and diastolic blood pressure and serum free IGF-I and IGFBP-3 levels in subjects suffering from type 1 diabetes. RESULTS: A highly significant inverse correlation was observed between serum free IGF-I levels and both systolic and diastolic blood pressure in subjects affected with type 1 diabetes. Similar but less significant relationships were observed for IGFBP-3, whose levels were also significantly and directly correlated with those of free IGF-I. The correlation between systolic and diastolic blood pressures with free IGF-I and between systolic blood pressure and IGFBP-3 levels were confirmed after adjusting for age, gender, age at diagnosis, disease duration, familial history, HBA1c, and amount of insulin administered by multivariate logistic regression analysis. A decrease in free IGF-I and IGFBP-3 levels, along with increases in blood pressure, significantly influenced the presence of diabetic complications, confirming how these molecules may be considered as severity markers for patients with type 1 diabetes as well as risk factors for altered pressure control linked diseases.