Difference Between Estimated GFR Based on Cystatin C Versus Creatinine and Incident Atrial Fibrillation: A Cohort Study of the UK Biobank

RATIONALE & OBJECTIVE

The difference between cystatin C-based and creatinine-based estimated glomerular filtration rate (eGFRdiff) has been suggested to reflect factors distinct from kidney function that are associated with cardiovascular risk. However, the association between eGFRdiff and atrial fibrillation (AF) risk has not been extensively evaluated.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Using data from the UK Biobank, this study included 363,494 participants with measured serum creatinine and cystatin C levels and without a prior diagnosis of AF or a history of related procedures.

EXPOSURE

Estimated GFRdiff, calculated as cystatin C-based eGFR minus creatinine-based eGFR. Estimated GFRdiff was also categorized as negative (<-15mL/min/1.73m2), midrange (-15 to 15mL/min/1.73m2), or positive (≥15mL/min/1.73m2).

OUTCOME

Incident AF.

ANALYTICAL APPROACH

Subdistribution hazard models were fit, treating death that occurred before development of AF as a competing event.

RESULTS

During the median follow-up period of 11.7 years, incident AF occurred in 18,994 (5.2%) participants. In the multivariable-adjusted model, participants with a negative eGFRdiff had a higher risk of incident AF (subdistribution HR [SHR], 1.25 [95% CI, 1.20-1.30]), whereas participants with a positive eGFRdiff had a lower risk of AF (SHR, 0.81 [95% CI, 0.77-0.87]) compared with those with a midrange eGFRdiff. When eGFRdiff was treated as a continuous variable in the adjusted model, every 10mL/min/1.73m2 higher eGFRdiff was associated with a 0.90-fold decrease in the risk of incident AF.

LIMITATIONS

A single measurement of baseline serum creatinine and cystatin C levels.

CONCLUSIONS

The difference between cystatin C- and creatinine-based eGFRs was associated with the risk of AF development. A higher eGFRdiff was associated with a lower risk of AF. These findings may have implications for the management of patients at risk of incident AF.

PLAIN-LANGUAGE SUMMARY

The difference between cystatin C-based estimated glomerular filtration rate (eGFR) and creatinine-based eGFR has recently gained attention as a potential indicator of cardiovascular outcomes influenced by factors other than kidney function. This study investigated the association between the differences in 2 eGFRs (cystatin C-based eGFR minus creatinine-based eGFR) and incident atrial fibrillation (AF) among>340,000 participants from the UK Biobank Study. Compared with those with a near zero eGFR difference, participants with a negative eGFR difference had a higher risk of AF, while those with a positive eGFR difference had a lower risk. These findings suggest that measuring eGFR differences may help identify individuals at a higher risk of developing AF.

Atrial fibrillation: primary prevention, secondary prevention, and prevention of thromboembolic complications: part 1

Atrial fibrillation (AF), is the most common sustained cardiac arrhythmia. It was once thought to be benign as long as the ventricular rate was controlled, however, AF is associated with significant cardiac morbidity and mortality. Increasing life expectancy driven by improved health care and decreased fertility rates has, in most of the world, resulted in the population aged ≥65 years growing more rapidly than the overall population. As the population ages, projections suggest that the burden of AF may increase more than 60% by 2050. Although considerable progress has been made in the treatment and management of AF, primary prevention, secondary prevention, and prevention of thromboembolic complications remain a work in progress. This narrative review was facilitated by a MEDLINE search to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2021. Atrial fibrillation was searched via the terms primary prevention, hyperthyroidism, Wolff-Parkinson-White syndrome, catheter ablation, surgical ablation, hybrid ablation, stroke prevention, anticoagulation, left atrial occlusion and atrial excision. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. In these two manuscripts, we discuss the current strategies available to prevent AF, then compare noninvasive and invasive treatment strategies to diminish AF recurrence. In addition, we examine the pharmacological, percutaneous device and surgical approaches to prevent stroke as well as other types of thromboembolic events.

Review article: diagnosis, pathophysiology and management of atrial fibrillation in cirrhosis and portal hypertension

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia and its management in cirrhosis can be challenging due to the altered hepatic metabolism of medications and increased risk of bleeding.

AIMS

To provide a comprehensive overview of the diagnosis, pathophysiology and management of AF in patients with cirrhosis from both a cardiology and a hepatology perspective.

METHODS

An extensive literature search was performed using the terms 'atrial fibrillation' and 'cirrhosis'. Guideline documents and consensus statements were explored.

RESULTS

The prevalence of AF in patients with cirrhosis ranges between 6.6% and 14.2%, while the incidence of new-onset AF in the post-operative period after liver transplant ranged between 6.8% and 10.2%. AF in patients with cirrhosis is associated with adverse outcomes in both pre-transplant and post-transplant settings, including an increased risk of stroke when compared to the general population. We review the pathogenesis of AF in general and in cirrhosis. This review also provides guidance on the management of AF, including the use of anticoagulation and rate versus rhythm control. In the absence of strict contraindications, all patients with cirrhosis and AF should be anticoagulated. The use of DOACs is preferred over vitamin K antagonists. In patients with a high bleeding risk, a DOAC with an approved antidote may be preferred.

CONCLUSIONS

Atrial fibrillation is increased in patients with cirrhosis. AF management requires careful consideration of treatment options. Since patients with cirrhosis were excluded from all major randomised clinical trials, dedicated research on the pathophysiology and management of AF in cirrhosis is needed.

Validating risk models versus age alone for atrial fibrillation in a young Dutch population cohort: should atrial fibrillation risk prediction be expanded to younger community members?

BACKGROUND

Advancing age is the primary selection criterion for community screening for atrial fibrillation (AF), with selection often restricted to those aged ≥65 years. If multivariable models were shown to have considerable additional value over age alone in predicting AF risk among younger individuals, AF screening could be expanded to patients with lower age, but with high AF risk as per a validated risk model.

METHODS

We validated risk models CHARGE-AF (Cohorts for Heart and Aging Research in Genomic Epidemiology model for AF) and FHS-AF (Framingham Heart Study model for AF), and risk scores CHA₂DS₂-VASc and CHA₂DS₂-VA, and presented their predictive abilities for 5-year and 10-year AF risk versus that of age alone in a young Dutch population cohort (PREVEND) free from AF at baseline. We assessed discrimination by the C-statistic and calibration by the calibration plot and stratified Kaplan-Meier plot using survey-weighted Cox models.

RESULTS

During 5-year and 10-year follow-up there were n=98 (2.46/1000 person-years) and n=249 (3.29/1000 person-years) new AF cases, respectively, among 8265 participants with mean age 49±13 years. CHARGE-AF and FHS-AF both showed good discrimination for 5-year and 10-year AF (C-statistic range 0.83-0.86) with accurate calibration for 5-year AF, but overestimation of 10-year AF risk in highest-risk individuals. CHA₂DS₂-VASc and CHA₂DS₂-VA relatively underperformed. Age alone showed similar discrimination to that of CHARGE-AF and FHS-AF both in the overall, young PREVEND cohort and in subgroups for lower age and lower stroke risk.

CONCLUSION

Multivariable models accurately discriminate for 5-year and 10-year AF risk among young European community-dwelling individuals. However, their additional discriminatory value over age alone was limited. Selection strategies for primary AF screening using multivariable models should not be expanded to younger individuals.

Association of proteinuria and incident atrial fibrillation in patients with diabetes mellitus: a population-based senior cohort study

Diabetes mellitus (DM) is considered an independent risk factor for atrial fibrillation (AF). The excess risk in relation to the presence of proteinuria has not been well elucidated. Our aim was to determine the association between the incidence of AF and proteinuria in diabetic population. A total of 240,499 individuals aged ≥ 60 years from the Korea National Health Insurance Service-Senior cohort from 2004 to 2014 were included. 4.2% of individuals with DM and 3.7% of controls were diagnosed with AF during a median follow-up period of 7.2 years. Amongst controls (participants without proteinuria and DM), DM only, proteinuria only, and DM with proteinuria groups, the crude incidences of AF were 0.58, 0.70, 0.96, 1.24 per 100 person-years respectively. Compared with controls, the weighted risk of AF was increased by 11% (hazard ratio = 1.11, 95% confidence interval = 1.02-1.20, P = .001), 48% (hazard ratio = 1.48, 95% confidence interval = 1.30-1.69, P < .001), and 66% (hazard ratio = 1.66, 95% confidence interval = 1.26-2.18, P < .001) in the DM only, proteinuria only, and DM with proteinuria groups, respectively (P for trend < .001). Degree of proteinuria in diabetic patients was associated with a significantly higher rate of incident AF in dose dependent manner. Thus, assessing proteinuria by a simple urine dipstick test could provide a useful adjunct to risk assessment for AF in elderly population with DM.

Two-Week Burden of Arrhythmias across CKD Severity in a Large Community-Based Cohort: The ARIC Study

BACKGROUND

CKD is associated with sudden cardiac death and atrial fibrillation (AF). However, other types of arrhythmia and different measures of the burden of arrhythmias, such as presence and frequency, have not been well characterized in CKD.

METHODS

To quantify the burden of arrhythmias across CKD severity in 2257 community-dwelling adults aged 71-94 years, we examined associations of major arrhythmias with CKD measures (eGFR and albuminuria) among individuals in the Atherosclerosis Risk in Communities study. Participants underwent 2 weeks of noninvasive, single-lead electrocardiogram monitoring. We examined types of arrhythmia burden: presence and frequency of arrhythmias and percent time in arrhythmias.

RESULTS

Of major arrhythmias, there was a higher prevalence of AF and nonsustained ventricular tachycardia among those with more severe CKD, followed by long pause (>30 seconds) and atrioventricular block. Nonsustained ventricular tachycardia was the most frequent major arrhythmia (with 4.2 episodes per person-month). Most participants had ventricular ectopy, supraventricular tachycardia, and supraventricular ectopy. Albuminuria consistently associated with higher AF prevalence and percent time in AF, and higher prevalence of nonsustained ventricular tachycardia. When other types of arrhythmic burden were examined, lower eGFR was associated with a lower frequency of atrioventricular block. Although CKD measures were not strongly associated with minor arrhythmias, higher albuminuria was associated with a higher frequency of ventricular ectopy.

CONCLUSIONS

CKD, especially as measured by albuminuria, is associated with a higher burden of AF and nonsustained ventricular tachycardia. Additionally, eGFR is associated with less frequent atrioventricular block, whereas albuminuria is associated with more frequent ventricular ectopy. Use of a novel, 2-week monitoring approach demonstrated a broader range of arrhythmias associated with CKD than previously reported.

Pathophysiology of atrial fibrillation and chronic kidney disease

Atrial fibrillation (AF) and chronic kidney disease (CKD) are closely related conditions with shared risk factors. The growing prevalence of both AF and CKD indicates that more patients will suffer from concurrent conditions. There are various complex interlinking mechanisms with important implications for the management of these patients. Furthermore, there is uncertainty regarding the use of oral anticoagulation (OAC) in AF and CKD that is reflected by a lack of consensus between international guidelines. Therefore, the importance of understanding the implications of co-existing AF and CKD should not be underestimated. In this review, we discuss the pathophysiology and association between AF and CKD, including the underlying mechanisms, risk of thrombo-embolic and bleeding complications, influence on stroke management, and evidence surrounding the use of OAC for stroke prevention.

High-Sensitivity Troponin-T and Cardiovascular Outcomes in the Community: Differences Between Women and Men

OBJECTIVE

To evaluate associations of high-sensitivity cardiac troponin-T (cTnT) with cardiovascular disease (CVD), heart failure (HF), and mortality in community-dwelling women and men.

PARTICIPANTS AND METHODS

A total of 8226 adults from the Prevention of Renal and Vascular End-stage Disease (PREVEND) cohort (1997-1998) were enrolled in a prospective observational study (mean age: 49 years; 50.2% women). Sex-specific associations of cTnT levels with future clinical outcomes were evaluated using adjusted Cox-regression models.

RESULTS

Measurable cTnT levels (≥3 ng/L) were detected in 1102 women (26.7%) and in 2396 men (58.5%). Baseline cTnT levels were associated with a greater risk of developing CVD in women than men [Hazard ratio (HR_women), 1.48 per unit increase in log₂-cTnT; 95% CI, 1.21 to 1.81 vs HR_men, 1.20; 95% CI, 1.07 to 1.35; P_interaction<.001]. Similar sex-related differences were observed for HF (P_interaction= .005) and mortality (P_interaction= .008). Further, compared with referent category (cTnT <3 ng/L), women with cTnT levels greater than or equal to 6 ng/L had a significantly increased risk for CVD (HR, 2.30; 95% CI, 1.45 to 3.64), HF (HR, 2.86; 95% CI, 1.41 to 5.80), and mortality (HR, 2.65; 95% CI, 1.52 to 4.61), whereas men with cTnT levels greater than or equal to 6 ng/L had a significantly increased risk only for CVD (HR, 1.51; 95% CI, 1.07 to 2.13).

CONCLUSION

Baseline cTnT levels were associated with future CVD, HF, and mortality in both sexes, and these associations were stronger in women. Future studies are needed to determine the value of cTnT in early diagnosis of CVD, particularly in women.

Deciphering the Pharmacological Mechanisms of Taohe-Chengqi Decoction Extract Against Renal Fibrosis Through Integrating Network Pharmacology and Experimental Validation In Vitro and In Vivo

Taohe-Chengqi decoction (THCQ), a classical traditional Chinese medicinal (TCM) formula, has been extensively used for treating chronic kidney disease (CKD). However, the biological activity and mechanisms of action of its constituents against renal fibrosis have not yet been investigated thoroughly. This study was aimed at devising an integrated strategy for investigating the bioactivity constituents and possible pharmacological mechanisms of the n-butanol extract of THCQ (NE-THCQ) against renal fibrosis. The n-butanol extract of THCQ was prepared by the solvent extraction method. The components of NE-THCQ were analyzed using UPLC-Q/TOF-MS/MS techniques and applied for screening the active components of NE-THCQ according to their oral bioavailability and drug-likeness index. Then, we speculated the potential molecular mechanisms of NE-THCQ against renal fibrosis through pharmacological network analysis. Based on data mining techniques and topological parameters, gene ontology, and pathway enrichment, we established compound-target (C-T), protein-protein interaction (PPI) and compound-target-pathway (C-T-P) networks by Cytoscape to identify the hub targets and pathways. Finally, the potential molecular mechanisms of NE-THCQ against renal fibrosis, as predicted by the network pharmacology analyses, were validated experimentally in renal tubular epithelial cells (HK-2) in vitro and against unilateral ureteral obstruction models in the rat in vivo. We identified 26 components in NE-THCQ and screened seven bioactive ingredients. A total of 118 consensus potential targets associated with renal fibrosis were identified by the network pharmacology approach. The experimental validation results demonstrated that NE-THCQ might inhibit the inflammatory processes, reduce ECM deposition and reverse EMT via PI3K/AKT/mTOR and HIF-1α/VEGF signaling pathways to exert its effect against renal fibrosis. This study identified the potential ingredients of the NE-THCQ by UPLC-Q/TOF-MS/MS and explained the possible mechanisms of NE-THCQ against renal fibrosis by integrating network pharmacology and experimental validation.

Clinical outcomes associated with kidney function changes in anticoagulated atrial fibrillation patients: An ancillary analysis from the BOREALIS trial

BACKGROUND

Patients with atrial fibrillation (AF) and chronic kidney disease represent a high-risk group for thromboembolism and bleeding.

AIMS

To explore the relationship between kidney function changes and outcomes of stroke/systemic embolism (SE), major bleeding and all-cause death in anticoagulated AF patients participating in the BOREALIS trial comparing efficacy and safety of once-weekly s.c. idrabiotaparinux to that of warfarin.

METHODS

Changes in kidney function by estimated glomerular filtration rate (eGFR) were calculated using the Chronic Kidney Disease Epidemiology Collaboration equation in 2765 AF patients. Trial adjudicated outcomes were determined.

RESULTS

After a mean follow-up of 394 days, in 94.4% of the included patients kidney function changed ranging from -30 mL/min to 30 mL/min. The incidence of stroke/SE and major bleeding was similar between patients with deteriorated (reduction in eGFR from baseline over follow-up) and preserved kidney function change (increase or no change in eGFR from baseline over follow-up) [stroke/SE: incidence rate (IR): 1.33%/year vs 1.80%/year; hazard ratio (HR) 0.74, 95% confidence interval (CI) 0.41-1.32, P = .30; major bleeding: IR 1.63%/year vs 1.49%/year, HR 1.10, 95% CI 0.61-1.97, P = .76]. On Cox regression analysis, patients with deteriorated kidney function were at higher risk for all-cause death, compared to patients with preserved kidney function (HR: 1.64, 95% CI: 1.02-2.63, P = .04).

CONCLUSION

In the BOREALIS trial, the risk of adjudicated stroke/SE, major bleedings, and all-cause death was not related to mild-moderate follow-up changes in kidney function (±30 mL/min). The risk of all-cause death was significantly increased in AF patients with abruptly deteriorating kidney function.

Fluctuating renal function and the risk of incident atrial fibrillation: a nationwide population-based study

Although chronic kidney disease is known to increase the risk of atrial fibrillation (AF), the impact of the variability of renal function on the risk of incident AF is unknown. We aimed to evaluate the association between variability of renal function and the risk of developing AF among the general population. We evaluated a total of 3,551,249 adults who had three annual health check-ups provided by the National Health Insurance Service. The variability of renal function was defined as GFR-VIM, which is variability independent of the mean (VIM) of creatinine-based estimated glomerular filtration rate (eGFR). The study population was divided into four groups (Q1-4) based on the quartiles of GFR-VIM, and the risks of incident AF by each group were compared. During a mean of 3.2 ± 0.5 years follow-up, incident AF occurred in 15,008 (0.42%) subjects. The incidence rates of AF increased from Q1 to Q4 (0.98, 1.42, 1.27, and 1.63 per 1,000 person-years, respectively). Adjusting with multiple variables, Q4 showed an increased risk of incident AF compared to Q1 (hazard ratio (HR) 1.125, 95% confidence interval (CI) 1.071-1.181). Variability of serum creatinine or other definitions of variability showed consistent results. On subgroup analyses, Q4 in males or those with a decreasing trend of eGFR had significantly increased risks of incident AF compared to Q1 (HR 1.127, 95% CI 1.082-1.175; and HR 1.115, 95% CI 1.059-1.173, respectively). High variability of eGFR was associated with an increased risk of incident AF, particularly in males or those with decreasing trends of eGFR during follow-up.

Association between PR interval prolongation and electro-anatomical substrate in patients with atrial fibrillation

Background

Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical routine. Left atrial (LA) electro-anatomical remodelling in AF patients indicates disease progression and is associated with poor therapeutic success. PR interval prolongation is associated with an increased risk for AF, however, the association between LA remodelling measured as low voltage areas (LVA) during catheter ablation and PR interval is unknown. The aim of this study was to investigate the association between PR interval prolongation and LVA in AF patients.

Methods

We studied 103 patients (62±12 years, 59% males, 34% persistent AF) undergoing first AF catheter ablation and presenting with sinus rhythm. PR interval prolongation was defined as PR >200ms and analysed in resting ECG before intervention. LVA were determined using high-density maps and defined as <0.5 mV.

Results

There were 24 patients (23%) with PR interval prolongation and 18 patients (17%) with LVA. There were significant correlations between PR prolongation with LVA, CHA₂DS₂-VASc score and eGFR (r² = 0.230, 0.216, and 0.307, all p<0.05). PR interval prolongation (OR 3.450, p = 0.024), persistent AF (OR 5.391, p = 0.002), and LA size (OR 1.117, p = 0.018) were significant predictors for LVA, while age (OR 1.072, p = 0.005), LVA (OR 3.450 p = 0.024) and eGFR (OR 0.962, p = 0.004) were associated with PR interval prolongation.

Conclusions

Beside persistent AF and LA size, PR interval prolongation might be useful for the prediction of electro-anatomical substrate in AF patients. Larger studies are needed to confirm these results.

Risk Factor Management in Atrial Fibrillation

Atrial fibrillation (AF) is the most common clinical arrhythmia and is associated with increased morbidity and mortality. There is growing evidence that numerous cardiovascular diseases and risk factors are associated with incident AF and that lone AF is rare. Beyond oral anticoagulant therapy, rate and rhythm control, therapy targeting risk factors and underlying conditions is an emerging AF management strategy that warrants better implementation in clinical practice. This review describes current evidence regarding the association between known modifiable risk factors and underlying conditions and the development and progression of AF. It discusses evidence for the early management of underlying conditions to improve AF outcomes. It also provides perspective on the implementation of tailored AF management in daily clinical practice.

Heart failure and inflammation-related biomarkers as predictors of new-onset diabetes in the general population

BACKGROUND

There is a strong reciprocal relationship between heart failure (HF) and diabetes mellitus (DM). Shared pathophysiological mechanisms might be a possible explanation. Therefore, we hypothesised that biomarkers linked to HF would also predict new-onset type 2 DM in the general population.

METHODS AND RESULTS

We utilized the Prevention of Vascular and Renal End-stage Disease (PREVEND) cohort (mean age 48.9years, 51% female) to study the relationship between HF and DM in 7953 participants free of baseline HF and DM. Multiple HF-related, inflammation-related and renal function-related biomarkers were evaluated regarding their predictive utility in new-onset DM. Incidence of DM in participants who developed HF was 11.8%, versus 5.4% in those who had not developed HF (p<0.001). Incidence of HF in participants who developed DM was 8.5%, versus 3.8% in those who had not developed DM (p<0.001). Classical HF biomarkers, NT-proBNP and hs-TnT were not associated with an increased risk for new-onset DM. However, inflammatory biomarkers hs-CRP [hazard ratio (HR) 1.16, (95% CI 1.05 to 1.29), p=0.005], procalcitonin [HR 1.34, (95% CI 1.07 to 1.69), p=0.012] and PAI-1 [HR 1.55, (95% CI 1.37 to 1.75), p<0.001] remained significantly associated with new-onset DM, even after multivariable adjustment for established predictors of DM.

CONCLUSIONS

Although HF and DM have a strong correlation with each other, systemic biomarkers that predict HF do not have a predictive value in new-onset DM. This suggests that other, indirect, pathophysiological mechanisms related to inflammation may explain their strong relation.

Proteinuria Detected by Urine Dipstick Test as a Risk Factor for Atrial Fibrillation: A Nationwide Population-Based Study

Proteinuria is one of the well-known risk factors for cardiovascular disease. However the impact of proteinuria on the incidence of atrial fibrillation (AF) is unclear. In this study, we investigated the association between proteinuria detected using urine dipstick test and the risk of AF. A total of 18,201,275 individuals were analyzed, who had no prior AF and had received biennial health checkups provided by the National Health Insurance Service between 2005 and 2008 in Korea. Incidences of AF were ascertained through the end of 2015. During a mean follow-up of 9.6 years, a total of 324,764 (1.8%) developed AF (1.86 per 1,000 person-years). In Cox regression models, proteinuria was associated with an increased risk of AF: adjusted HR and 95% CI of AF occurrence were 1.13 (1.10-1.16), 1.34 (1.31-1.38), 1.53 (1.48-1.58), 1.82 (1.71-1.94), and 1.86 (1.61-2.16) in individuals with trace, 1+, 2+, 3+, and 4+ proteinuria, respectively, compared with those without proteinuria. The result was consistent even after additional adjustment for estimated glomerular filtration rate. In addition, the risk of AF further increased or decreased according to the follow-up dipstick test results. Thus, proteinuria measured with a dipstick test might be considered a potent risk factor for AF development.