Elevated glycated hemoglobin levels impair blood pressure in children and adolescents with type 1 diabetes mellitus

Blood pressure in adolescents and young adults with type 1 diabetes: data from the Australasian Diabetes Data Network registry

AIM

Hypertension increases complication risk in type 1 diabetes (T1D). We examined blood pressure (BP) in adolescents and young adults with T1D from the Australasian Diabetes Data Network, a prospective clinical diabetes registry in Australia and New Zealand.

METHODS

This was a longitudinal study of prospectively collected registry data.

INCLUSION CRITERIA

T1D (duration ≥ 1 year) and age 16-25 years at last visit (2011-2020). Hypertension was defined as (on ≥ 3 occasions) systolic BP and/or diastolic BP > 95^th percentile for age < 18 years, and systolic BP > 130 and/or diastolic BP > 80 mmHg for age ≥ 18 years. Multivariable Generalised Estimating Equations were used to examine demographic and clinical factors associated with BP in the hypertensive range across all visits.

RESULTS

Data from 6338 young people (male 52.6%) attending 24 participating centres across 36,655 T1D healthcare visits were included; 2812 (44.4%) had BP recorded at last visit. Across all visits, 19.4% of youth aged < 18 years and 21.7% of those aged ≥ 18 years met criteria for hypertension. In both age groups, BP in the hypertensive range was associated with male sex, injection (vs. pump) therapy, higher HbA1c, and higher body mass index.

CONCLUSIONS

There is a high proportion of adolescents and young adults reported with BP persistently in hypertensive ranges. Findings flag the additive contribution of hypertension to the well-established body of evidence indicating a need to review healthcare models for adolescents and young adults with T1D.

Comparison of Glycosylated Haemoglobin, Blood Pressure, and Anthropometric Measurements Depending on Gender and Bodyweight State in Adolescents

Background/Objective: The greatest anthropometric and physiological changes occur during adolescence. Assessment of growth patterns is necessary to prevent future health risks. Aims: To describe the values of glycosylated haemoglobin (HbA1c), systolic (SBP) and diastolic (DBP) blood pressure, triceps skinfold, and abdominal circumference according to gender and age (between 12 and 17 years), as well as explore the differences between body weight conditions. Methods: A descriptive cross-sectional study was carried out, including 4130 adolescents between 12 and 17 years old. SBP and DBP, HbA1c, triceps skinfold, and abdominal circumference were evaluated. Results: Significant differences were observed between males and females for HbA1c (p < 0.001), SBP (p < 0.001), triceps curl (p < 0.001), and abdominal circumference (p < 0.001), independently of the age group. Regardless of gender and age groups, significant differences were observed between overweight/obese and normal-weight adolescents in SBP (p < 0.001), DBP (p < 0.001 to 0.009), triceps skinfold (p < 0.001), and abdominal perimeter (p < 0.001). Conclusions: Our findings revealed higher SBP, DBP, triceps skinfold, and abdominal circumference in overweight/obese adolescents compared to normal-weight adolescents in both genders.

Chronic diabetes and hypertension impair the in vivo functional response to phenylephrine independent of α1-adrenoceptor expression

Diabetes and hypertension can coexist and exacerbate each other. In the early stages of diabetes, there is a decreased vascular response of the sympathetic nervous system (SNS), probably due to lower expression of α₁-adrenoceptors; however, it is unclear how diabetes in advanced stages changes the functionality of the SNS, especially the expression of α₁-adrenoceptors. Thus, the aim of this work was to analyse the functional response to phenylephrine, a selective α₁-adrenoceptor agonist, and the expression of α₁-adrenoceptors in chronic diabetes and hypertension. Male SHR and WKY rats aged 10-12 weeks were administered either streptozotocin (60 mg/kg i.p.) or a vehicle (control group). Eight weeks after administration, dose-response curves to phenylephrine were generated and the gene and protein expression of α₁-adrenoceptor subtypes (α_1A-, α_1B- and α_1D-adrenoceptors) in the heart and aorta were measured. The response to phenylephrine was diminished in hypertensive rats and in normotensive diabetic rats. The coexistence of both diabetes and hypertension produced an even smaller response to phenylephrine than that observed for each condition separately. In the heart and aorta of diabetic rats, no changes in α_1A-, α_1B- or α_1D-adrenoceptor mRNA expression were observed; however, protein expression was increased, mainly for the α_1D-adrenoceptor. Hypertension increased mRNA and protein expression of α₁-adrenoceptors in a tissue-dependent manner. The coexistence of both diabetes and hypertension produced differences in the regulation of mRNA and protein expression (increase or decrease) in both the heart and aorta. In conclusion, diabetes, hypertension and the coexistence of both pathologies impairs the in vivo response to phenylephrine. However, the differences in α_1A-, α_1B- and α_1D-adrenoceptor expression cannot explain the reduced response to the agonist. This should be further explored in future experiments.