Type 1 Diabetes Accelerates Progression of Coronary Artery Calcium Over the Menopausal Transition: The CACTI Study.

OBJECTIVE: Type 1 diabetes is associated with a higher risk of cardiovascular disease (CVD) in women. Although menopause increases risk of CVD, it is uncertain how menopause affects risk of CVD in women with type 1 diabetes. We examined whether risk of CVD changes differentially in women with and those without type 1 diabetes over the transition through menopause. RESEARCH DESIGN AND METHODS: Premenopausal women with type 1 diabetes (n = 311) and premenopausal women without diabetes (n = 325) enrolled in the Coronary Artery Calcification in Type 1 Diabetes (CACTI) study and attended up to four study visits over 18 years. Coronary artery calcium (CAC) volume was measured from computed tomography scans obtained at each visit. Longitudinal repeated-measures modeling estimated the effect of diabetes on CAC volume over time and the effect of menopause on the diabetes-CAC relationship. RESULTS: CAC volume was higher at baseline and increased more over time in women with type 1 diabetes than in women without diabetes. A significant diabetes-by-menopause interaction was found (P < 0.0001): postmenopausal women with type 1 diabetes had significantly higher CAC volumes than premenopausal women (5.14 ± 0.30 vs. 2.91 ± 0.18 mm3), while there was no difference in women without diabetes (1.78 ± 0.26 vs. 1.78 ± 0.17 mm3). This interaction remained significant after adjusting for CVD risk factors. CONCLUSIONS: Type 1 diabetes was associated with higher CAC volume and accelerated progression of CAC over time. Menopause increased CAC progression more in women with diabetes than in women without diabetes independent of age and other CVD risk factors known to worsen with menopause.

Type 1 diabetes onset at young age is associated with compromised bone quality.

Women with type 1 diabetes (T1D) are at increased risk for fracture. We studied the association of T1D and young age at T1D onset (T1D onset before 20 years) on bone structural quality. 24 postmenopausal women with T1D (mean age 60.9 years, mean T1D duration 41.7 years) and 22 age, sex- and body mass index (BMI)-matched controls underwent dual X-ray absorptiometry (DXA) measured areal bone mineral density (aBMD) at the lumbar spine, hip and distal radius. Bone mass, geometry and estimated bone strength were assessed at distal and shaft of non-dominant radius and tibia using peripheral quantitative computed tomography (pQCT). Postmenopausal women with T1D had lower trabecular volumetric bone mineral density (vBMD) (LSM ±â€¯SEM; 166.1 ±â€¯8.2 vs 195.9 ±â€¯8.3 mg/cm3, p = 0.02) and compressive bone strength (24.6 ±â€¯1.8 vs 30.1 ±â€¯1.9 mg2/mm4, p = 0.04) at the distal radius compared to controls adjusting for age, BMI and radius length. At the distal radius, patients with young onset T1D had lower total vBMD (258.7 ±â€¯19.7 vs 350.8 ±â€¯26.1 mg/cm3, p = 0.02) and trabecular vBMD (141.4 ±â€¯11.6 vs 213.6 ±â€¯15.4 mg/cm3, p = 0.003) compared to adult onset T1D patients adjusting for age, BMI and the radius length. At the tibial shaft, young onset T1D patients had larger endosteal circumference (39.1 ±â€¯1.2 vs 32.1 ±â€¯1.6 mm, p = 0.005) with similar periosteal circumference (67.1 ±â€¯0.9 vs 65.1 ±â€¯1.2 mm, p = 0.2) resulting in reduced cortical thickness (4.4 ±â€¯0.1 vs 5.2 ±â€¯0.1 mm, p = 0.004) compared to adult onset T1D patients adjusting for age, BMI and the tibia length. There was no difference in the lumbar spine, femoral neck, total hip and distal radius DXA-measured aBMD between subjects with T1D and controls. T1D is associated with lower trabecular vBMD at the distal radius. T1D onset before age 20 is associated with cortical bone size deficits at the tibial shaft.

Serum Uromodulin Predicts Less Coronary Artery Calcification and Diabetic Kidney Disease Over 12 Years in Adults With Type 1 Diabetes: The CACTI Study.

OBJECTIVE: Novel biomarkers are needed to better predict coronary artery calcification (CAC), a marker of subclinical atherosclerosis, and diabetic kidney disease (DKD) in type 1 diabetes. We evaluated the associations between serum uromodulin (SUMOD [a biomarker associated with anti-inflammatory and renal protective properties]), CAC progression, and DKD development over 12 years. RESEARCH DESIGN AND METHODS: Participants (n = 527, 53% females) in the Coronary Artery Calcification in Type 1 Diabetes (CACTI) study were examined during 2002-2004, at a mean age of 39.6 ± 9.0 years and a median duration of diabetes of 24.8 years. Urine albumin-to-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR) determined by the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine equation were measured at baseline and after a mean follow-up period of 12.1 ± 1.5 years. Elevated albumin excretion was defined as ACR ≥30 mg/g, rapid GFR decline (>3 mL/min/1.73 m2/year), and impaired GFR as eGFR <60 mL/min/1.73 m2. SUMOD was measured on stored baseline plasma samples (Meso Scale Discovery). CAC was measured using electron beam computed tomography. CAC progression was defined as a change in the square root-transformed CAC volume of ≥2.5. RESULTS: Higher baseline SUMOD level conferred lower odds of CAC progression (odds ratio 0.68; 95% CI 0.48-0.97), incident elevated albumin excretion (0.37; 0.16-0.86), rapid GFR decline (0.56; 0.35-0.91), and impaired GFR (0.44; 0.24-0.83) per 1 SD increase in SUMOD (68.44 ng/mL) after adjustment for baseline age, sex, systolic blood pressure, LDL cholesterol, and albuminuria/GFR. The addition of SUMOD to models with traditional risk factors also significantly improved the prediction performance for CAC progression and incident DKD. CONCLUSIONS: Higher baseline SUMOD level predicted lower odds of both CAC progression and incident DKD over 12 years in adults with type 1 diabetes.

Copeptin and Estimated Insulin Sensitivity in Adults With and Without Type 1 Diabetes: The CACTI Study.

OBJECTIVES: Copeptin, a surrogate marker for vasopressin, is elevated in participants with insulin resistance (IR) and type 2 diabetes. Whereas adults with type 1 diabetes also demonstrate elevated copeptin concentrations and IR compared to controls without diabetes, the relationship between copeptin and IR in type 1 diabetes is unclear. METHODS: Participants with (n=209) and without (n=244) type 1 diabetes in the Coronary Artery Calcification in Type 1 Diabetes (CACTI) study were assessed for serum copeptin, vitals, estimated glomerular filtration rate, urinary albumin-to-creatinine ratio, glycated hemoglobin and lipid panels. Estimated insulin sensitivity (eIS) was calculated by validated equations in participants with and without type 1 diabetes. The relationships among copeptin, IR, waist circumference (WC) and body mass index (BMI) were examined with unadjusted and adjusted linear regression models. RESULTS: Copeptin was correlated with eIS (R=-0.17, R2=0.029), WC (R=0.16, R2=0.026) and BMI (R=0.22, R2=0.048) for type 1 diabetes and with eIS (R=-0.37, R2=0.14), WC (R=0.40, R2=0.16) and BMI (R=0.25, R2=0.063) in non-type 1 diabetes. In multivariable analysis, copeptin correlated with total cholesterol (beta±SE: -0.12±0.04, p=0.008) and low-density lipoprotein (beta±SE: -0.11±0.04, p=0.01) in type 1 diabetes. In non-type 1 diabetes, copeptin was associated with WC (beta±SE: 0.14±0.04, p=0.0024), BMI (beta±SE: 0.13±0.04, p=0.007) and eIS (beta±SE: -0.14±0.04, p=0.0013). CONCLUSIONS: Copeptin does not correlate with markers of IR in type 1 diabetes but strongly correlates in non-type 1 diabetes. Thus, elevated vasopressin activity and IR appear to be independent risk factors for vascular complications in type 1 diabetes.

Lower objectively measured physical activity is linked with perceived risk of hypoglycemia in type 1 diabetes.

AIMS: Compare physical activity (PA) levels in adults with and without type 1 diabetes and identify diabetes-specific barriers to PA. METHODS: Forty-four individuals with type 1 diabetes and 77 non-diabetic controls in the Coronary Artery Calcification in Type 1 Diabetes study wore an accelerometer for 2 weeks. Moderate-to-vigorous physical activity (MVPA) was compared by diabetes status using multiple linear regression. The Barriers to Physical Activity in Type 1 Diabetes questionnaire measured diabetes-specific barriers to PA, and the Clarke hypoglycemia awareness questionnaire measured hypoglycemia frequency. RESULTS: Individuals with type 1 diabetes engaged in less MVPA, fewer bouts of MVPA, and spent less time in MVPA bouts per week than individuals without diabetes (all p < 0.05), despite no difference in self-reported PA (p > 0.05). The most common diabetes-specific barrier to PA was risk of hypoglycemia. Individuals with diabetes reporting barriers spent less time in MVPA bouts per week than those not reporting barriers (p = 0.047). CONCLUSIONS: Individuals with type 1 diabetes engage in less MVPA than those without diabetes despite similar self-reported levels, with the main barrier being perceived risk of hypoglycemia. Adults with type 1 diabetes require guidance to meet current PA guidelines and reduce cardiovascular risk.

Plasma biomarkers improve prediction of diabetic kidney disease in adults with type 1 diabetes over a 12-year follow-up: CACTI study.

Background: The objective of the study was to determine whether plasma biomarkers of kidney injury improve the prediction of diabetic kidney disease (DKD) in adults with type 1 diabetes (T1D) over a period of 12 years. Methods: Participants (n = 527, 53% females) in the Coronary Artery Calcification in T1D (CACTI) Study were examined during 2002-04, at a mean (± standard deviation) age of 39.6 ± 9.0 years with 24.8 years as the median duration of diabetes. Urine albumin-to-creatinine (ACR) and estimated glomerular filtration rate (eGFR) by CKD-EPI (chronic kidney disease epidemiology collaboration) creatinine were measured at the baseline and after mean follow-up of 12.1 ± 1.5 years. Albuminuria was defined as ACR ≥30 mg/g and impaired GFR as eGFR <60 mL/min/1.73 m2. Kidney injury biomarkers (Meso Scale Diagnostics) were measured on stored baseline plasma samples. A principal component analysis (PCA) identified two components: (i) kidney injury molecule-1, calbindin, osteoactivin, trefoil factor 3 and vascular endothelial growth factor; and (ii) ß-2 microglobulin, cystatin C, neutrophil gelatinase-associated lipocalin and osteopontin that were used in the multivariable regression analyses. Results: Component 2 of the PCA was associated with increase in log modulus ACR [ß ± standard error (SE): 0.16 ± 0.07, P = 0.02] and eGFR (ß ± SE: -2.56 ± 0.97, P = 0.009) over a period of 12 years after adjusting for traditional risk factors (age, sex, HbA1c, low-density lipoprotein cholesterol and systolic blood pressure and baseline eGFR/baseline ACR). Only Component 2 of the PCA was associated with incident-impaired GFR (odds ratio 2.08, 95% confidence interval 1.18-3.67, P = 0.01), adjusting for traditional risk factors. The addition of Component 2 to traditional risk factors significantly improved C-statistics and net-reclassification improvement for incident-impaired GFR (ΔAUC: 0.02 ± 0.01, P = 0.049, and 29% non-events correctly reclassified, P < 0.0001). Conclusions: Plasma kidney injury biomarkers can help predict development of DKD in T1D.

Reduced brachial artery distensibility in patients with type 1 diabetes.

BACKGROUND AND AIMS: In patients with type 1 diabetes mellitus (T1D), cardiovascular disease (CVD) events are more common and occur earlier in life than in non-diabetics. Reduced brachial artery distensibility (BrachD) is an independent risk factor for development of CVD. Our aim was to determine if adults with T1D have lower BrachD compared to adults without diabetes and also to determine how age and gender affect the relationship of BrachD with T1D status. MATERIALS AND METHODS: BrachD was measured using the Dynapulse instrument in 829 participants (352 with T1D, 477 non-diabetics). An ANCOVA model was used to test the association of BrachD with age, sex, and T1D, and the significance of an age*sex*T1D interaction. RESULTS: Mean BrachD was lower in T1D patients vs. controls (6.43±1.46 vs. 7.16±1.48 % change per mmHg, p<0.0001). In a model adjusted for age, T1D, and sex, the interaction of age*T1D*sex was significant (p=0.0045). Younger women both with and without T1D had higher BrachD than men with and without T1D, but older women with and without T1D had lower BrachD compared to older men with and without T1D. Women with T1D had a steeper decline in BrachD with age than nondiabetic women. CONCLUSIONS: BrachD is lower in T1D patients than in non-diabetics, indicating increased vascular stiffness. Younger females have higher BrachD than males, but the decline with age in BrachD is steeper for women, particularly among those with T1D. BrachD may be an inexpensive, non-invasive method to ascertain increased CVD risk in this population.

Is the risk and nature of CVD the same in type 1 and type 2 diabetes?

The incidence of both type 1 and type 2 diabetes is increasing globally, most likely explained by environmental changes, such as changing exposures to foods, viruses, and toxins, and by increasing obesity. While cardiovascular disease (CVD) mortality has been declining recently, this global epidemic of diabetes threatens to stall this trend. CVD is the leading cause of death in both type 1 and type 2 diabetes, with at least a two- to fourfold increased risk in patients with diabetes. In this review, the risk factors for CVD are discussed in the context of type 1 and type 2 diabetes. While traditional risk factors such as dyslipidemia, hypertension, and obesity are greater in type 2 patients than in type 1 diabetes, they explain only about half of the increased CVD risk. The role for diabetes-specific risk factors, including hyperglycemia and kidney complications, is discussed in the context of new study findings.