Arterial Stiffness and Chronic Kidney Disease Progression in Children

BACKGROUND AND OBJECTIVES

CKD has been linked to increased arterial stiffness in adults, but data in children with CKD remain conflicting. We aimed to investigate the longitudinal dynamics and determinants of pulse wave velocity in children with CKD and its association with CKD progression.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed an analysis of the Cardiovascular Comorbidity in Children with Chronic Kidney Disease (4C) study, which prospectively followed children aged 6-17 years with CKD stages 3-5. Follow-up was censored at the time of KRT initiation. Two separate analyses were performed: with absolute pulse wave velocity (primary outcome) and with pulse wave velocity standardized to height (z score; restricted to participants ≤17 years) as a sensitivity analysis.

RESULTS

In total, 667 patients with a mean baseline eGFR of 27 ml/min per 1.73 m2 were included. Pulse wave velocity above the 95th percentile was observed in 124 (20%) patients at baseline. Absolute pulse wave velocity increased gradually over the median follow-up of 2.7 (interquartile range, 0.7-4.4) years, whereas pulse wave velocity z score remained relatively stable. Absolute pulse wave velocity over time associated with time; older age; higher mean arterial pressure, LDL cholesterol, and albuminuria; and lower ferritin. Pulse wave velocity z score (n=628) was associated with the same variables and additionally, with higher diastolic BP z score, lower height z score, younger age, and girls. Of 628 patients, 369 reached the composite end point of CKD progression (50% eGFR loss, eGFR <10 ml/min per 1.73 m2, or the start of KRT) during a median follow-up of 2.4 (interquartile range, 0.9-4.6) years. Pulse wave velocity z score did not associate with CKD progression by univariable or multivariable proportional hazard analysis correcting for the established predictors eGFR, proteinuria, and BP.

CONCLUSIONS

Pulse wave velocity is increased in children with CKD but does not associate with eGFR or CKD progression.

The Effects of Statin Treatment on Serum Ferritin Levels: A Systematic Review and Meta-Analysis

Background: Statins are the most widely used drugs for decreasing elevated serum LDL-cholesterol (LDL-C) and thus for the prevention of atherosclerotic cardiovascular disease (ASCVD), but they have also some pleiotropic effects, including anti-inflammatory properties. Atherosclerosis is a low-grade inflammatory disease, and elevated ferritin is considered to be one of the markers of inflammation. Since the results of studies on the effects of statins on serum ferritin levels are conflicting, this meta-analysis was performed. Methods: A literature search was performed using major electronic databases (MEDLINE/PubMed, Scopus, Embase, and ISI Web of Science) from inception up to 5 March 2022 to find studies evaluating the effect of different statins on serum ferritin levels. The effect size was determined using weighted mean differences (WMDs) and the corresponding 95% confidence intervals (CIs). Results: The meta-analysis of nine studies (1611 patients) analyzing the effects of statins on serum ferritin levels that were included showed a significant decrease in circulating ferritin levels caused by statins. The results did not suggest any significant association between the changes in concentrations of serum ferritin and the duration of treatment with statins. Conclusions: Statin therapy decreases the circulating concentrations of ferritin, which might be beneficial for the prevention and/or progression of ASCVD. This effect might be explained by the anti-inflammatory effects and maybe some other pleiotropic effects of statins and not by their lipid-lowering effects.

Maternal Iron Status in Early Pregnancy and Blood Pressure Throughout Pregnancy, Placental Hemodynamics, and the Risk of Gestational Hypertensive Disorders

BACKGROUND

In nonpregnant populations, higher serum ferritin, which reflects high iron stores, is associated with an increased risk of hypertension. We hypothesized that a dysregulated maternal iron status in early pregnancy may lead to impaired gestational hemodynamic adaptations, leading to an increased risk of gestational hypertensive disorders.

OBJECTIVES

We examined the associations of maternal iron status with maternal blood pressure, placental hemodynamic parameters, and the risks of gestational hypertensive disorders.

METHODS

In a population-based prospective cohort study among 5983 pregnant women, we measured maternal serum ferritin, transferrin saturation, serum iron, and transferrin concentrations at a median of 13.2 weeks gestation (95% range, 9.6-17.6). Maternal blood pressure was measured in early pregnancy, mid pregnancy, and late pregnancy, and placental hemodynamic parameters in mid pregnancy and late pregnancy were measured by ultrasound. Information on gestational hypertensive disorders was collected from medical records. We examined the associations of maternal early pregnancy iron status with maternal systolic and diastolic blood pressure, placental hemodynamic parameters, and the risks of gestational hypertensive disorders using linear and logistic regression models.

RESULTS

Higher maternal early pregnancy serum ferritin concentrations were associated with higher systolic and diastolic blood pressure throughout pregnancy in the basic models (P values < 0.05). After adjustment for maternal inflammation, sociodemographic and lifestyle factors, higher maternal early pregnancy serum ferritin concentrations were only associated with a higher early pregnancy diastolic blood pressure [0.27 (95% CI, 0.03-0.51) mmHg per SD score increase in serum ferritin] and with a higher mid pregnancy umbilical artery pulsatility index (P < 0.05). No associations with the risk of gestational hypertensive disorders were present.

CONCLUSIONS

No consistent associations were present of maternal iron status in early pregnancy with gestational hemodynamic adaptations or the risks of gestational hypertensive disorders. Further studies are needed to examine the potential role of iron metabolism in the development of gestational hypertensive disorders within higher-risk populations.

Ferritin modifies the relationship between inflammation and arterial stiffness in hypertensive patients with different glucose tolerance

Background

Ferritin, a crucial element for iron homeostasis, is associated with chronic diseases characterized by subclinical inflammation such as essential arterial hypertension and type 2 diabetes mellitus (T2DM), showing a prognostic value in different clinical settings. We investigated whether ferritin is associated with arterial stiffness (AS), an early indicator of atherosclerosis, and if it could act as effect modifier on the relationship between inflammation and AS in hypertensive patients with different glucose tolerance.

Methods

We enrolled 462 newly diagnosed untreated hypertensive (HT) patients. All subjects underwent an oral glucose tolerance test. Insulin sensitivity was assessed by MATSUDA index and ferritin levels were estimated by immunoradiometric assay. AS was defined by carotid-femoral pulse wave velocity (PWV).

Results

Out of 462 patients, 271 showed normal glucose tolerance (HT/NGT), 146 impaired glucose tolerance (HT/IGT) and 45 were diabetic (HT/T2DM). Iron levels significantly decreased and transferrin and ferritin significantly increased from the first to the third group. PWV values were significantly higher in HT/IGT and HT/T2DM patients. PWV was related directly with ferritin, high sensitivity C reactive protein (hs-CRP), transferrin, and inversely with MATSUDA index. Ferritin resulted the strongest determinant of PWV explaining a 14.9% of its variation; moreover it was a strong modifier of the relationship between hs-CRP and PWV. The estimated augmentation in PWV portended by a fixed increase in hs-CRP, was higher across increasing values of ferritin.

Conclusion

Ferritin represents an independent risk factor of arterial stiffness in our study population and a strong effect modifier on the relationship between inflammation and PWV. However, further studies are needed to fully elucidate the potential role of this biomarker in human atherosclerosis.

Association of serum ferritin levels with metabolic syndrome and insulin resistance in a Chinese population

AIMS

Increased iron is associated with type 2 diabetes, dyslipidemia, and high blood pressure. Therefore, serum ferritin may be a suitable biomarker to detect metabolic syndrome (MetS). We investigated the relationship between serum ferritin, and the prevalence of MetS and insulin resistance (IR).

METHODS

This cross-sectional study assessed 2,786 Chinese participants, aged 25-75 years. MetS was defined using the 2006 International Diabetes Federation guidelines. IR was assessed with homeostasis model assessment estimated IR (HOMA-IR). Regression analysis was used to estimate the association between serum ferritin and the prevalence of MetS and IR.

RESULTS

MetS prevalence within each serum ferritin quartile (Q1-4) was 31.7%, 37.1%, 43.6%, and 55.4%, respectively in men (P<0.001), and 30.1%, 34.8%, 48.2%, and 66.9%, respectively in women (P<0.001). Increased serum ferritin correlated with the number of MetS components (P<0.001). The odds ratio for MetS in the ferritin Q4 group was 1.95 (1.39-2.73) for men and 1.66(1.12-2.47) for women, compared with Q1. Serum ferritin correlated positively with HOMA-IR in men (regression coefficient: 0.058, P=0.009) and women (regression coefficient: 0.082, P=0.001).

CONCLUSION

MetS prevalence increased with elevated serum ferritin levels, and serum ferritin levels were independently associated with MetS and IR.