Peripheral arterial stiffness is correlated with intrarenal arteriolosclerosis according to biopsies from patients with kidney disease

Serum levels of sonic hedgehog in patients with IgA nephropathy are closely associated with intrarenal arteriolar lesions

BACKGROUND

Intrarenal arteriolar disease is a major risk factor for poor prognosis in immunoglobulin A nephropathy (IgAN). The morphologic factor sonic hedgehog (SHH) plays an important role in a variety of vascular diseases, so it may be directly or indirectly involved in the process of renal arteriolar disease. The purpose of this study was to investigate the correlation between serum SHH levels and renal arteriole disease in patients with IgAN.

METHODS

Subjects with primary IgAN diagnosed by renal biopsy performed between October 2018 and August 2019 at the First Medical Center of the Chinese PLA General Hospital were recruited. Blood specimens were collected from the patients within 1 week before renal biopsy after they signed an informed consent form, and healthy controls were recruited for blood specimen collection during the same period. The concentration of serum SHH was measured by enzyme-linked immunosorbent assay in this population.

RESULTS

Serum SHH levels were significantly lower in the IgAN group than in the control group. 41 of the 94 subjects diagnosed with IgAN had severe renal arteriolosclerosis and, compared to their less severely affected counterparts, were older, more hypertensive, and characterized by lower levels of SHH, higher levels of tubular atrophy/interstitial fibrosis and a higher Lee's classification. Serum SHH concentration was found to be an independent predictor of severe intrarenal arteriolosclerosis in IgAN subjects after correction using multivariate analysis.

CONCLUSION

In this study, serum SHH levels were found to be significantly lower in patients with IgAN than in healthy subjects. Serum SHH may serve as a noninvasive biomarker of intrarenal arteriolosclerosis in patients with IgAN.

The effect of arteriosclerosis on new-onset renal damage in diabetic patients

The aim of this study was to investigate the effect of arteriosclerosis on new-onset renal damage in a Chinese community population with diabetes. Patients with diabetes who had attended at least one physical examination after the Brachial-ankle pulse wave velocity (BaPWV) test from 2010 to 2018 were selected as subjects. A total of 4,462 patients were included in the study cohort. BaPWV levels <1,400 cm/s, 1,400-1,799 cm/s, and ≥1,800 cm/s were applied to divide the subjects into a normal arterial stiffness group, borderline atherosclerosis group and atherosclerosis group. Renal damage was defined by isolated proteinuria, isolated eGFR <60 mL/min/1.73 m², proteinuria and eGFR <60 mL/min/1.73 m². A Cox proportional risk model was used to analyze the effect of different groups on new-onset renal damage. After a median follow-up of 2.85 (1.88-4.90) years, Cox proportional risk models showed that after adjusting for risk factors, compared with the normal group, the HR and 95% CI of the risk of new-onset renal damage were 1.29 (95% CI: 0.95-1.76) and 1.59 (95% CI: 1.14-2.22) in the borderline atherosclerosis group and the atherosclerosis group, respectively. Atherosclerosis is a risk factor for new-onset renal damage, especially new-onset proteinuria, in diabetic patients.

Clinical Factors Associated with Arterial Stiffness in Chronic Kidney Disease

BACKGROUND

Arterial stiffness influences the prognosis of patients with end-stage kidney disease; however, the factors that promote arterial stiffness in chronic kidney disease (CKD) patients remain unknown. We aimed to explore the clinical factors associated with arterial stiffness in CKD.

METHODS

Between September 2017 and September 2022, all CKD patients treated at the Department of Nephrology, General Hospital of the Chinese People's Liberation Army, excluding dialysis patients, were screened and their medical records within the last month were collected. Arterial stiffness was measured by the augmentation index (AIx). The correlative clinical factors with arterial stiffness were explored in different linear regression models.

RESULTS

559 patients were included in the study. AIx@75 increased as the deterioration of CKDG1-CKDG5, with values of 1 (-9, 11), 5.5 (-4, 13.25), 9 (0, 16), 12 (1.5, 23.5), and 22 (13, 28), respectively (Z = 63.03, p < 0.001). Multivariate linear regression analysis showed that AIx@75 was positively associated with female sex (β = 8.926, 95% confidence interval (CI) 6.291, 11.562, p < 0.001), age (β = 0. 485, 95% CI 0.39, 0.58, p < 0.001), mean arterial pressure (MAP) (β = 0.255, 95% CI 0.159, 0.35, p < 0.001), and was negatively associated with ACEI/ARB (β = -4.466, 95% CI -6.963, -1.969, p < 0.001) and glucocorticoid (β = -3.163, 95% CI -6.143, -0.183, p = 0.038). Smoking, eGFR, hemoglobin, and cause of disease were associated with AIx@75 in multivariate linear regression models when considering factors partly.

CONCLUSIONS

Female, age, smoking, MAP, eGFR, cause of disease, ACEI/ARB, and glucocorticoid were found to be associated with atherosclerosis in CKD patients.

Endothelial function, arterial stiffness and Framingham risk score in chronic kidney disease: A prospective observational cohort study

The aim of this study was to assess the role of endothelial function measured by the reactive hyperemia index (RHI), arterial stiffness measured by the augmentation index (AIx), and Framingham's cardiovascular disease (CVD) risk score (FRS) in kidney function decline in patients with chronic kidney disease (CKD). The RHI and AIx@75 (adjusted for 75 heart beats per minute), both derived from peripheral arterial tonometry (EndoPAT), were measured in 428 CKD patients aged 18 years old and older during hospitalization. We evaluated kidney function and its decline (incident ≥40% decline in estimated glomerular filtration rate [eGFR] or initiation of renal replacement therapy) associated with the RHI, AIx@75, and FRS during follow-up for a median of 36 months. The mean age of the participants was 56 years old, and 63.8% were men. In Spearman correlation analysis, the FRS, AIx@75, and RHI levels inversely correlated with eGFR. Over a median follow-up of 36 months, 122 participants experienced kidney function decline. In multivariate Cox analysis, only the FRS remained independently associated with the progression of kidney function (HR, 1.37; 95% CI, 1.14 to 1.64; P = 0.001). Multivariable-adjusted spline regression models showed a positive linear relationship between the FRS and the risk of kidney function decline (P-overall = 0.001, P-nonlinear = 0.701). However, adding the FRS to a model containing kidney function markers did not improve risk prediction for kidney outcome (category-free net reclassification improvement index [cf-NRI] = 0.179, P = 0.084; integrated discrimination improvement [IDI] = 0.017, P = 0.128). Additionally, the increased risk of the outcome associated with an elevated FRS was particularly evident among CKD patients with eGFR ≥60 ml/min/1.73  m² (eGFR ≥ 60 ml/min/1.73 m² vs.< 60 ml/min/1.73 m², P for interaction =  0.022). Participants with higher FRS levels were at increased risk of kidney function decline, emphasizing the important role of traditional CVD risk factors in the progression of CKD.

Osteocalcin association with vascular function in chronic kidney disease

Osteocalcin (OCN) is a bone‐derived and vitamin K dependent hormone that affects energy metabolism and vascular calcification. The relationship between serum OCN and vascular function in patients with chronic kidney disease (CKD) is uncertain. This study investigated the association between serum OCN and vascular function as expressed with reactive hyperemia index (RHI) and augmentation index (AIx) measured by Endo‐PAT 2000 device. This cross‐sectional analysis was based on 256 pre‐dialysis CKD patients who had completed the Endo‐PAT 2000 test and serum OCN at the First Center of Chinese PLA Hospital from November 2017 to December 2019. Based on whether the RHI was less than 1.67, the patients were divided into endothelial dysfunction and normal endothelial function groups. Multiple logistic and linear regression were used to analyze the association between OCN and vascular function. Subgroup analyses were performed to examine the effects of OCN on vascular function in different CKD populations. After multivariate adjustment, CKD with low OCN were more likely to have endothelial dysfunction (OR: 0.794; 95%CI: 0.674‐0.934; P = .006); on the contrary, patients with high OCN had a higher degree of arterial stiffness (standardized β: 0.174; P = .003). Subgroup analyses showed that higher OCN was associated with severe arterial stiffness but a better endothelial function in young (age < 65 years, P_RHI/P_AIx@75 = .027/.011), male (P_RHI/P_AIx@75 = .040/.016), patients with a history of hypertension (P_RHI/P_AIx@75 = .004/.009) or diabetes (P_RHI/P_AIx@75 = .005/.005), and in early CKD (P_RHI/P_AIx@75 = .014/.015). In conclusion, serum OCN correlates with vascular function in CKD patients: beneficial for endothelial function but detrimental to arterial stiffness.

The treatment of mild OSA with CPAP or mandibular advancement device and the effect on blood pressure and endothelial function after one year of treatment

STUDY OBJECTIVES

To evaluate and compare the effects of continuous positive airway pressure (CPAP), use of a mandibular advancement device (MAD), and no treatment on 24-hour ambulatory blood pressure monitoring and peripheral arterial tonometry at 6 and 12 months follow-up in individuals with mild obstructive sleep apnea (OSA), and in a subgroup who had an apnea-hypopnea index of < 5 events/h and adherence of ≥ 4 hours per night (effective-treatment subgroups).

METHODS

The inclusion criteria were individuals with mild obstructive sleep apnea, any sex, age between 18 and 65 years, and a body mass index of ≤ 35 kg/m². Patients were randomized into CPAP, MAD, and no-treatment groups. The evaluations included physical examination, full polysomnography, 24-hour ambulatory blood pressure monitoring, and peripheral arterial tonometry at baseline and after 6 and 12 months. A generalized linear mixed model was used for comparisons.

RESULTS

The CPAP and MAD groups had lower apnea-hypopnea indexes than the control group at 6 and 12 months, and the CPAP group had higher blood oxygen levels (SpO₂) than the MAD group. The MAD group had more hours of treatment per night and better adaptation to treatment than the CPAP group (MAD: 5.7 ± 2.7 h/night; CPAP: 3.8 ± 3.4 h/night; MAD: 16% did not adapt; CPAP: 42% did not adapt). No differences were found in the total sample and effective treatment in relation to peripheral arterial tonometry or 24-hour ambulatory blood pressure monitoring outcomes.

CONCLUSIONS

Treatment of mild obstructive sleep apnea with CPAP or MAD did not improve blood pressure or endothelial function after 1 year, even in patients with effective treatment.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Continuous Positive Airway Pressure and Oral Appliances Treatments in Mild Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/NCT01461486; Identifier: NCT01461486.

Noninvasive markers of arterial stiffness and renal outcomes in patients with chronic kidney disease

Our study aimed to explore the intercorrelations of brachial‐ankle pulse wave velocity (baPWV), ankle‐brachial index (ABI), ambulatory arterial stiffness index (AASI), 24‐hour mean pulse pressure (24‐h   PP), and augmentation index (AIx, AIx@75, the AIx standardized to a heart rate of 75) and compare the effectiveness of these markers for predicting renal outcomes. A total of 117 patients with chronic kidney disease (CKD) who received noninvasive arterial stiffness examinations were enrolled. We used correlation analysis and linear regression to explore the correlations between these five arterial stiffness markers and the Cox proportional hazards model and receiver operator characteristic (ROC) curve to assess the associations of markers with kidney disease outcomes. The median (interquartile range) of age and eGFR were 61 (49‐65) years and 50.5 (35.5‐84.1) ml/min/1.73 m², respectively. In Pearson correlation analysis, baPWV was significantly associated with 24‐h  PP (r = .531, p < .001), AIx@75 (r = .306, p < .001). Additionally, 24‐h  PP was associated with AASI (r = .507, p < .001) and AIx@75 (r = .217, p = .019). During follow‐up for a median of 25 months, 26.5% (n = 31) of patients had a composite outcome; of these, 10 initiated dialysis, 17 had 40% eGFR loss, and 4 died. Increased AASI, 24‐h  PP, and baPWV were associated with poor renal outcomes in a univariate Cox analysis. After adjusting for age, sex, MAP, eGFR, and 24 hours proteinuria, 1‐SD increase in AASI and 24‐h  PP was associated with renal outcomes. The ROC analysis yielded the largest area under the curve (AUC) of 0.727 (95% CI: 0.624 to 0.831; p < .001) for 24  ‐h PP. When the Youden's index was at its maximum, the 24‐h PP value was 52 mmHg. In conclusion, 24‐h  PP, baPWV, and AIx@75 were linked well to one another. Arterial stiffness is a target for delaying the decline in kidney function. The use of 24‐h  PP as an arterial stiffness marker should be valued in CKD clinical practice.

Effects of external counter-pulsation on endothelial function assessed by peripheral artery tonometry, levels of glycaemia and metabolic markers in individuals with type 2 diabetes mellitus

BACKGROUND AND AIMS

External counter-pulsation (ECP) generates sheer stress thereby improving endothelial function and anginal symptoms in coronary artery disease. Endothelial dysfunction is also involved in the pathogenesis of T2DM. The aim of this pilot study was to investigate the use of ECP at different doses in improving endothelial function and glycaemic markers in T2DM.

METHODS

This prospective study involved 46 subjects with T2DM randomly assigned to receive 35 sessions of ECP at different regimens (0.5 h versus 1 h) and duration (7 versus 12 weeks). Endothelial function was evaluated by reactive hyperaemia index (RHI) via peripheral arterial tonometry at the start, midpoint and end of study. Other secondary outcomes included fasting glucose, HOMA-IR, HbA1c, blood pressure, lipid profile, weight and vibration sense.

RESULTS

There was no change in RHI across all 3 regimens of ECP individually or collectively at the end of the study (ΔRHI +0.01%, p = 0.458). Glycaemic markers also remained unchanged at endpoint. Subgroup analysis showed an improvement in RHI (ΔRHI +20.6%, p = 0.0178) in subjects with more severe endothelial dysfunction at baseline.

CONCLUSION

ECP did not show a beneficial effect on endothelial function or glycemic control in this South-East Asian population with T2DM at any of the three regimens. This may partly be explained by less severe endothelial dysfunction and less insulin resistance in our population at baseline.