Persons with type 1 diabetes have low blood oxygen levels in the supine and standing body positions

Twenty-Four week Taichi training improves pulmonary diffusion capacity and glycemic control in patients with Type 2 diabetes mellitus

This study evaluated the effect of 24-week Taichi training and Taichi plus resistance band training on pulmonary diffusion capacity and glycemic control in patients with Type 2 diabetes mellitus (T2DM). Forty-eight patients with T2DM were randomly divided into three groups: Group A-Taichi training: practiced Taichi 60 min/day, 6 days/week for 24 weeks; Group B-Taichi plus resistance band training: practiced 60-min Taichi 4 days/week plus 60-min resistance band training 2 days/week for 24 weeks; and Group C-controls: maintaining their daily lifestyles. Stepwise multiple regression analysis was applied to predict diffusion capacity of the lungs for carbon monoxide (DLCO) by fasting blood glucose, insulin, glycosylated hemoglobin (HbA1c), tumour necrosis factor alpha (TNF-α), von Willebrand Factor (vWF), interleukin-6 (IL-6), intercellular adhesion molecule 1 (ICAM-1), endothelial nitric oxide synthase (eNOS), nitric oxide (NO), endothelin-1 (ET-1), vascular endothelial growth factor, and prostaglandin I-2. Taichi with or without resistance band training significantly improved DLCO, increased insulin sensitivity, eNOS and NO, and reduced fasting blood glucose, insulin, HbA1c, TNF-α, vWF, IL-6, ICAM-1, and ET-1. There was no change in any of these variables in the control group. DLCO was significantly predicted (R2 = 0.82) by insulin sensitivity (standard-β = 0.415, P<0.001), eNOS (standard-β = 0.128, P = 0.017), TNF-α (standard-β = -0.259, P = 0.001), vWF (standard-β = -0.201, P = 0.007), and IL-6 (standard-β = -0.175, P = 0.032) in patients with T2DM. The impact of insulin sensitivity was the most important predictor for the variation of DLCO based on the multiple regression modeling. This study demonstrates that 24-week Taichi training and Taichi plus resistance band training effectively improve pulmonary diffusion capacity and blood glycemic control in patients with T2DM. Variation of DLCO is explained by improved insulin sensitivity and endothelial function, and reduced inflammatory markers, including TNF-α, vWF, and IL-6.

In vivo molecular imaging of cardiac angiogenesis in persons with and without type 2 diabetes: A cross-sectional 68 Ga-RGD-PET study

AIMS

To assess cardiac angiogenesis in type 2 diabetes by positron emission tomography (PET) tracer [⁶⁸ Ga]Ga-NODAGA-E[(cRGDyK)]₂ (⁶⁸ Ga-RGD) imaging.

METHODS

Cross-sectional study including 20 persons with type 2 diabetes and 10 non-diabetic controls (CONs). Primary prespecified outcome was difference in cardiac angiogenesis (cardiac ⁶⁸ Ga-RGD mean target-to-background ratio [TBR_mean ]) between type 2 diabetes and CONs. Secondary outcome was to investigate associations between cardiac angiogenesis and kidney function and other risk factors.

RESULTS

Participants with type 2 diabetes had a mean ± SD age of 61 ± 9 years, 30% were women, median (IQR) diabetes duration of 11 (6-19) years and 3 (15%) had a history of cardiovascular disease. The CONs had comparable age and sex distribution to the participants with type 2 diabetes, and none had a history of coronary artery disease. Myocardial flow reserve was lower in type 2 diabetes (2.7 ± 0.6) compared with CONs (3.4 ± 1.2) ( p  = 0.03) and coronary artery calcium score was higher (562 [142-905] vs. 1 [0-150] p  = 0.04). Cardiac ⁶⁸ Ga-RGD TBR_mean was similar in participants with type 2 diabetes (0.89 ± 0.09) and CONs (0.89 ± 0.10) ( p  = 0.92). Cardiac ⁶⁸ Ga-RGD TBR_mean was not associated with estimated glomerular filtration rate, urine albumin creatinine ratio, cardiovascular disease, coronary artery calcium score or baroreflex sensitivity, neither in pooled analyses nor in type 2 diabetes.

CONCLUSIONS

Cardiac angiogenesis, evaluated with ⁶⁸ Ga-RGD PET, was similar in type 2 diabetes and CONs. Cardiac angiogenesis was not associated with kidney function or other risk markers in pooled analyses or in analyses restricted to type 2 diabetes.

Lower Blood Oxygen Saturation is Associated With Microvascular Complications in Individuals With Type 1 Diabetes

CONTEXT

Blood oxygen saturation (SpO2) is lower in type 1 diabetes (T1D) compared with nondiabetic controls. Hypoxia (low tissue oxygenation) is thought to be a risk factor for progression of diabetic complications, but it is unknown whether hypoxemia (low SpO2) is associated with diabetic complications.

OBJECTIVE

To test if hypoxemia is associated with presence of diabetic complications in T1D.

DESIGN, SETTING, AND METHODS

Cross-sectional study in persons with T1D divided by a previously suggested threshold in low (<96%) and high (≥96%) SpO2, measured in the supine position with pulse oximetry. Complications included albuminuria (2 of 3 consecutive measurements ≥30 mg/g), any diabetic retinopathy, neuropathy, and history of cardiovascular disease (CVD). Odds ratios were adjusted for age, diabetes duration, sex, smoking, physical activity, body mass index, systolic blood pressure, and blood hemoglobin.

RESULTS

We included 659 persons, 23 (3.5%) with low and 636 (96.5%) with high SpO2. In total, 151 (23%) had albuminuria, 233 (36%) had retinopathy, 231 (35%) had neuropathy, and 72 (11%) had CVD. The adjusted odds ratio (95% CI, P value) for low vs high SpO2 was 3.4 (1.3-8.7, P = 0.01) for albuminuria, 2.8 (1.0-7.5, P = 0.04) for retinopathy, 5.8 (1.8-18.6, P < 0.01) for neuropathy, and nonsignificant for CVD (0.6 [0.2-2.4, P = 0.51]).

CONCLUSIONS

SpO2 below 96% was associated with increased presence of albuminuria, retinopathy, and neuropathy in T1D, but not with CVD. Whether hypoxemia could be a target of intervention to prevent progression in microvascular disease in type 1 diabetes should be investigated.

Blood oxygen saturation is lower in persons with pre-diabetes and screen-detected diabetes compared with non-diabetic individuals: A population-based study of the Lolland-Falster Health Study cohort

Aims

Low blood oxygen saturation is associated with increased mortality and persons with diabetes have sub-clinical hypoxemia. We aimed to confirm the presence of sub-clinical hypoxemia in pre-diabetes, screen-detected diabetes and known diabetes.

Methods

Pre-diabetes was defined as hemoglobin A1C (HbA1C) ≥ 42 mmol/mol and <48 mmol/mol; known diabetes as history or treatment of diabetes; screen-detected diabetes as no history or treatment of diabetes and HbA1C ≥ 48 mmol/mol. Blood oxygen saturation was measured with pulse oximetry. Urine albumin-to creatinine ratio (UACR) was measured on a single spot urine.

Results

The study included 829 adults (≥18 years) with diabetes (713 (86%) with known diabetes; 116 (14%) with screen-detected diabetes) and 12,747 without diabetes (11,981 (94%) healthy controls; 766 (6%) with pre-diabetes). Mean (95% CI) blood oxygen saturation was 96.3% (96.3% to 96.4%) in diabetes which was lower than in non-diabetes [97.3% (97.2-97.3%)] after adjustment for age, gender, and smoking (p < 0.001), but significance was lost after adjustment for BMI (p = 0.25). Sub-groups with pre-diabetes and screen-detected diabetes had lower blood oxygen saturations than healthy controls (p-values < 0.01). Lower blood oxygen saturation was associated with higher UACR.

Conclusions

Persons with pre-diabetes and screen-detected diabetes have sub-clinical hypoxemia, which is associated with albuminuria.

Kidney oxygenation, perfusion and blood flow in people with and without type 1 diabetes

Background

We used magnetic resonance imaging (MRI) to study kidney energetics in persons with and without type 1 diabetes (T1D).

Methods

In a cross-sectional study, 15 persons with T1D and albuminuria and 15 non-diabetic controls (CONs) underwent multiparametric MRI (3 Tesla Philips Scanner) to quantify renal cortical and medullary oxygenation (R₂*, higher values correspond to higher deoxyhaemoglobin concentration), renal perfusion (arterial spin labelling) and renal artery blood flow (phase contrast). Analyses were adjusted for age, sex, systolic blood pressure, plasma haemoglobin, body mass index and estimated glomerular filtration rate (eGFR).

Results

Participants with T1D had a higher median (Q1; Q3) urine albumin creatinine ratio (UACR) than CONs [46 (21; 58) versus 4 (3; 6) mg/g; P < .0001] and a lower mean ± SD eGFR (73 ± 32 mL/min/1.73 m² versus 88 ± 15 mL/min/1.73 m²;  P = .12), although not significantly. Mean medullary R₂* was lower in T1D (34 ± 6/s versus 38 ± 5/s; P < .01) corresponding to a higher oxygenation. R₂* was not different in the cortex. Cortical perfusion was lower in T1D (163 ± 40 versus 224 ± 49 mL/100 g/min; P < .001). Renal artery blood flow was lower in T1D than in CONs (360 ± 130 versus 430 ± 113 mL/min; P = .05). In T1D, lower cortical oxygenation and renal artery blood flow were both associated with higher UACR and lower eGFR (P < .05).

Conclusions

Participants with T1D and albuminuria exhibited higher medullary oxygenation than CONs, despite lower cortical perfusion and renal artery blood flow. This might reflect perturbed kidney energetics leading to a higher setpoint of medullary oxygenation in T1D. Lower cortical oxygenation and renal artery blood flow were associated with higher UACR and lower eGFR in T1D.