Sex differences and sex steroids influence on the presentation and severity of cardiovascular autonomic neuropathy of patients with type 1 diabetes.

BACKGROUND: Sex differences characterize cardiovascular outcomes in patients with type 1 diabetes. Cardioautonomic neuropathy is a common complication of type 1 diabetes that associates increased morbi-mortality. Data regarding the interplay between sex and cardiovascular autonomic neuropathy are scarce and controversial in these patients. We aimed to address sex-related differences in the prevalence of seemingly asymptomatic cardioautonomic neuropathy in type 1 diabetes, and their associations with sex steroids. METHODS: We conducted a cross-sectional study including 322 consecutively recruited patients with type 1 diabetes. Cardioautonomic neuropathy was diagnosed using Ewing's score and power spectral heart rate data. We assessed sex hormones by liquid chromatography/tandem mass spectrometry. RESULTS: When considering all subjects as a whole, asymptomatic cardioautonomic neuropathy prevalence was not significantly different between women and men. When age was taken into account, the prevalence of cardioautonomic neuropathy was similar among young men and those > 50 years. However, in women > 50 years, the prevalence of cardioautonomic neuropathy doubled that of young women [45.8% (32.6; 59.7) vs. 20.4% (13.7; 29.2), respectively]. The OR of having cardioautonomic neuropathy was 3.3 higher in women > 50 years than in their younger counterparts. Furthermore, women presented more severe cardioautonomic neuropathy than men. These differences were even more marked when women were classified according their menopausal status instead of age. Peri- and menopausal women had an OR 3.5 (1.7; 7.2) of having CAN compared with their reproductive-aged counterparts [CAN prevalence: 51% (37; 65) vs. 23% (16; 32), respectively]. A binary logistic regression model (R2: 0.161; P = 0.001) displayed age > 50 years as a significant determinant of cardioautonomic neuropathy only in women. Androgens were positively associated with heart rate variability in men, and negatively in women. Accordingly, cardioautonomic neuropathy was associated with increased testosterone/estradiol ratio in women but to decreased testosterone concentrations in men. CONCLUSIONS: Menopause in women with type 1 diabetes is accompanied by an increase in the prevalence of asymptomatic cardioautonomic neuropathy. This age-related excess risk of cardioautonomic neuropathy is not observed in men. Men and women with type 1 diabetes have opposite associations between circulating androgens and indexes of cardioautonomic function. Trial registration ClinicalTrials.gov Identifier: NCT04950634.

Investigating the Link between Intermediate Metabolism, Sexual Dimorphism, and Cardiac Autonomic Dysfunction in Patients with Type 1 Diabetes.

Sexual dimorphism influences cardiovascular outcomes in type 1 diabetes (T1D), with women facing a higher relative risk of macrovascular events compared to men, especially after menopause. This study hypothesizes that abnormalities in intermediate metabolism may be associated with cardiac autonomic neuropathy (CAN) in T1D. We aim to assess low molecular weight metabolites (LMWM) as markers of CAN in T1D, considering the effects of sexual dimorphism and age. In this cross-sectional study, we included 323 subjects with T1D (147 women and 176 men), with a mean age of 41 ± 13 years. A total of 44 women and 41 men were over 50 years old. CAN was assessed using Ewing's tests, and serum metabolites were analyzed by proton nuclear magnetic resonance spectroscopy (1H-NMR). Patients with CAN had lower levels of valine, isoleucine, and threonine, and higher levels of lactate, compared to those without CAN. These differences persisted after adjusting for BMI and estimated glucose disposal rate (eGDR). In a logistic regression model (R² = 0.178, p < 0.001), the main determinants of CAN included isoleucine [Exp(ß) = 0.972 (95% CI 0.952; 0.003)], age [Exp(ß) = 1.031 (95% CI 1.010; 1.053)], A1c [Exp(ß) = 1.361 (95% CI 1.058; 1.752)], and microangiopathy [Exp(ß) = 2.560 (95% CI 1.372; 4.778)]. Sex influenced LMWM profiles, with over half of the metabolites differing between men and women. However, no interactions were found between CAN and sex, or between sex, age, and CAN, on metabolomics profiles. Our findings suggest an association between CAN and LMWM levels in T1D. The sexual dimorphism observed in amino acid metabolites was unaffected by the presence of CAN.

"Arterial stiffness is not associated with changes in the circadian pattern of blood pressure in patients with type 1 diabetes mellitus and cardiovascular autonomic dysfunction".

INTRODUCTION: Cardiovascular autonomic neuropathy (CAN) associates an abnormal circadian pattern in blood pressure (BP) regulation that might be aggravated by the coexistence of arterial stiffness. We aimed to evaluate the effect of arterial stiffness in the circadian rhythm of BP in patients with type 1 diabetes and CAN. METHODS: Cross-sectional study including 56 consecutive patients with type 1 diabetes and CAN, with (n = 28) or without (n = 24) arterial stiffness as defined by an ankle-brachial index above 1.2. CAN was diagnosed by BP and heart rate responses to active standing and cardiovascular autonomic reflex tests. Absence of nocturnal decrease in BP-"non-dipping" pattern- was defined by a daytime to nighttime decrease in mean BP smaller than 10%. RESULTS: The study's subjects mean age was 40 ± 11 years-old, their mean duration of diabetes was 22 ± 10 years, and their mean A1c was 7.9 ± 1.5%. A "non-dipping" pattern was observed in 28 patients (54%) regardless of the presence or absence of arterial stiffness. Age, waist circumference, body mass index, and A1c, were introduced as independent variables into a multiple regression analysis. The stepwise model (R2: 0.113, p = 0.016) retained only A1c levels (ß: ‒ 0.333, 95% confidence interval [CI]: -3.10 to -0.33) as significant predictor of the percentage of nighttime decrease in mean BP. CONCLUSIONS: A non-dipping pattern in BP is very common in patients with type 1 diabetes presenting with subclinical CAN and is associated with a poorer metabolic control. On the contrary, coexistence of arterial stiffness is not associated with abnormalities in circadian BP regulation.

High serum copeptin may be a marker of an increased carotid intima-media thickness in asymptomatic patients with type 1 diabetes.

We aimed to study the association of copeptin with carotid intima-media thickness in 60 patients with type 1 diabetes (T1DM-patients). Our results suggest that copeptin might improve the stratification of cardiovascular risk in T1DM-patients. Further research is needed to determine the value in identifying carotid disease of this biochemical marker.

Point-of-care sural nerve conduction could predict the presence of cardiovascular autonomic neuropathy in type 1 diabetes mellitus.

AIMS: Assessment for cardiovascular autonomic neuropathy (CAN) in patients with type 1 diabetes mellitus remains time-consuming in the clinical setting. We aimed to examine the diagnostic performance of a portable point-of-care diagnostic tool (POCD) for assessing sural nerve conduction during the screening of CAN. METHODS: Nerve amplitude (AMPPOCD ) and conduction velocity (CVPOCD ) were measured in a cross-sectional study including 198 asymptomatic patients with type 1 diabetes. CAN was diagnosed by the Ewing score and power spectral heart rate [low-frequency (LF) and high-frequency (HF) activity]. Diagnostic accuracy was determined by ROC curves. RESULTS: CVPOCD and AMPPOCD showed positive correlations with LF and HF, and a negative correlation with age. Overall, AMPPOCD had an 81.7% accuracy in identifying CAN [AUC = 0.817 (95% CI 0.692-0.942)] with an AMPPOCD ≤6 µV showing 90% sensitivity and 73% specificity. In a stepwise binary logistic regression analysis, the model (R2 : 0.297; P < 0.001) retained the duration of type 1 diabetes [ß: 1.131 (95% CI: 1.051-1.216); P = 0.001) and A1c [ß: 2.131 (95% CI: 1.060-4.283); P = 0.034) as significant predictors of CAN. The combination of AMPPOCD ≤6 µV + a type 1 diabetes duration of ≥8 years maximized the sensitivity, showing a diagnostic performance of 87% [AUC = 0.867 (95% CI 0.769-0.965)] with 90%, 76%, and 99%, sensitivity, specificity, and NPV, respectively. Adding A1c ≥ 7% to this model maintained accuracy [AUC = 0.867 (95% CI: 0.788-0.963) and NPV (99%), while increasing specificity to 84%. CONCLUSIONS: The combination of AMPPOCD with A1c and the duration of type 1 diabetes mellitus showed a good performance for the detection of asymptomatic CAN, making POCD an easy and rapid test for its routine screening in the clinical setting.

Impact of excluding hyperglycemia from international diabetes federation metabolic syndrome diagnostic criteria on prevalence of the syndrome and its association with microvascular complications, in adult patients with type 1 diabetes.

BACKGROUND: We aimed to determine, in patients with type 1 diabetes (T1DM), the impact of excluding hyperglycemia as a criterion from the International Diabetes Federation (IDF) definition of the metabolic syndrome (MetS), both on its prevalence and on its association with micro and macrovascular complications and markers of subclinical inflammation. METHODS: A cross-sectional design, including 280 patients with T1DM. We defined MetS by three different models: (i) the standard IDF criteria, (ii) a modification consisting of excluding of hyperglycemia as a criterion (modified IDF criteria) and (iii) a modification consisting in changing the hyperglycemia by insulin resistance (MetS + IR model) defined by the estimated glucose disposal rate. Microvascular complications and cardioautonomic neuropathy were assessed. We measured an inflammatory panel including high sensitivity C reactive protein, erythrocyte sedimentation rate, homocysteine, and fibrinogen concentrations. RESULTS: After excluding hyperglycemia, the prevalence of MetS was 6.4% (95%CI: 4.1 to 9.9) compared with 20.7% (95%CI: 16.3 to 25.8) using standard IDF criteria. After adjusting for duration of diabetes, all three MetS definitions increased the odds for having microvascular complications [OR: 6.012 (2.208-16.307) for modified definition; OR: 5.176 (2.555-10.486) for standard definition and [OR: 3.374 (1.649-8.456) for MetS+IR model]. However, the both modified IDF models for MetS showed better predictive performance than standard criteria for suffering from neuropathy, nephropathy, cardiovascular disease and were associated with markers of subclinical inflammation. CONCLUSIONS: The prevalence of MetS significantly varies as a function whether or not hyperglycemia is included as a diagnostic criterion. The subset of patients fulfilling the modified MetS definitions may reflect better the concept of metabolic syndrome in T1DM. These modified definitions were accompanied by a poorer metabolic control and lipid profile, showing the worse inflammatory biomarker profiles and higher odds for micro- and macrovascular complications. In patients with T1DM, the inclusion of insulin resistance instead of hyperglycemia as a criterion of MetS may be of interest in routine clinical practice.

Fasting serum copeptin and asymptomatic peripheral artery disease: No association in patients with type 1 diabetes mellitus.

OBJECTIVE: As copeptin is associated with lower-extremity amputation in patients with type 1 diabetes mellitus (T1DM), our study aimed to address the putative association between copeptin and asymptomatic peripheral artery disease (aPAD) in those patients. DESIGN AND METHODS: This observational cross-sectional study included 112 patients with T1DM from a larger cohort (ClinicalTrials.gov: NCT02910271), selected (1:2) as per the presence of aPAD (n = 37) or not (n = 75). aPAD was evaluated by ankle-brachial index (ABI), toe-brachial index (TBI), and peripheral Doppler ultrasound. The two groups of patients were matched by age, gender distribution and duration of T1DM. Fasting serum copeptin was measured by high-sensitivity ELISA, and its relationships with clinical and biochemical variables as well as aPAD were evaluated too. RESULTS: The study population was aged 42 ± 8 years, duration of T1DM was 27 ± 7 years, and mean HbA1c was 7.7 ± 1.1%. No significant differences in copeptin concentrations were found between patients with or without aPAD (16.9 ± 10.8 vs 17.3 ± 14.7 pmol/L, respectively; P = 0.462). Considering all patients as a whole, copeptin correlated with systolic blood pressure (SBP; ρ = -0.209, P = 0.027), eGFR ρ = -0.271, P = 0.004), and serum sodium (ρ = -0.208, P = 0.027), but not with ABI (ρ = -0.068, P = 0.476). Stepwise multiple linear regression analysis (R2: 0.059; P = 0.035) retained SBP (ß: -0.219, 95% CI: -1.391; -0.089) as the only significant predictor of copeptin concentration. CONCLUSION: As serum copeptin does not appear to be associated with aPAD in patients with T1DM, further studies are now needed to elucidate whether it has any other potential role to play in the subclinical vascular disease of this patient population.