Risks of Death and Stroke in Patients Undergoing Hemodialysis With New-Onset Atrial Fibrillation: A Competing-Risk Analysis of a Nationwide Cohort

Atrial fibrillation as a prognostic indicator of myocardial infarction and cardiovascular death: a systematic review and meta-analysis

This study aimed to investigate whether atrial fibrillation (AF) predicts myocardial infarction (MI) or cardiovascular (CV) death. AF is a well-established risk factor for thrombotic stroke and all-cause mortality. PubMed, EmBase, and Cochrane Central were searched for articles comparing the incidence rates of MI, CV death, or CV events between AF and non-AF patients. Relative risk ratio (RR) was used as effect estimate. Crude and adjusted RRs were calculated. Data were pooled using a random-effects model. The meta-analysis included 27 studies. In the unadjusted analysis, AF patients had a nonsignificant trend toward a higher risk of MI compared with non-AF patients; however, a significant association was found. The crude data analysis showed that AF was associated with increased risk of CV death (P < 0.05) and CV events (P < 0.05). These associations remained significant after pooling data from adjusted models (CV death: RR = 1.95, 95% CI 1.51–2.51, P < 0.05; CV events: RR = 2.10, 95% CI 1.50–2.95, P < 0.05). These results showed that AF is an independent risk factor for MI, CV death, and CV events.

Dipeptidyl Peptidase-4 Inhibitors, Peripheral Arterial Disease, and Lower Extremity Amputation Risk in Diabetic Patients

BACKGROUND

Recent studies have elucidated the vascular protective effects of dipeptidyl peptidase-4 (DPP-4) inhibitors. However, to date, no large-scale studies have been carried out to determine the impact of DPP-4 inhibitors on the occurrence of peripheral arterial disease, and lower extremity amputation risk in patients with type 2 diabetes mellitus.

METHODS

We conducted a retrospective registry analysis using Taiwan's National Health Insurance Research Database to investigate the correlation between the use of DPP-4 inhibitors and risk of peripheral arterial disease in patients with type 2 diabetes mellitus. A total of 82,169 propensity score-matched pairs of DPP-4 inhibitor users and nonusers with type 2 diabetes mellitus were examined for the period 2009 to 2011.

RESULTS

The mean age of the study subjects was 58.9 ± 12.0 years, and 54% of subjects were male. During the mean follow-up of 3.0 years (maximum, 4.8 years), a total of 3369 DPP-4 inhibitor users and 3880 DPP-4 inhibitor nonusers were diagnosed with peripheral arterial disease. Compared with nonusers, DPP-4 inhibitor users were associated with a lower risk of peripheral arterial disease (hazard ratio 0.84; 95% confidence interval, 0.80-0.88). Additionally, DPP-4 inhibitor users had a decreased risk of lower-extremity amputation than nonusers (hazard ratio 0.65; 95% confidence interval, 0.54-0.79). The association between use of DPP-4 inhibitors and risk of peripheral arterial disease was also consistent in subgroup analysis.

CONCLUSIONS

This large-scale nationwide population-based cohort study is the first to demonstrate that treatment with DPP-4 inhibitors is associated with lower risk of peripheral arterial disease occurrence and limb amputation in patients with type 2 diabetes mellitus.

Association of pre-hospital theophylline use and mortality in chronic obstructive pulmonary disease patients with sepsis

BACKGROUND

Although theophylline has been shown to have anti-inflammatory effects, the therapeutic use of theophylline before sepsis is unknown. The aim of our study was to determine the effect of theophylline on COPD patients presenting with sepsis.

METHODS

This nationwide, population-based, propensity score-matched analysis used data from the linked administrative databases of Taiwan's National Health Insurance program. Patients with COPD who were hospitalized for sepsis between 2000 and 2011 were divided into theophylline users and non-users. The primary outcome was 30-day mortality. The secondary outcome was in-hospital death, intensive care unit admission, and need for mechanical ventilation. Cox proportional hazard model and conditional logistic regression were used to calculate the risk between groups.

RESULTS

A propensity score-matched cohort of 51,801 theophylline users and 51,801 non-users was included. Compared with non-users, the 30-day (HR 0.931, 95% CI 0.910-0.953), 180-day (HR 0.930, 95% CI 0.914-0.946), 365-day (HR 0.944, 95% CI 0.929-0.960) and overall mortality (HR 0.965, 95% CI 0.952-0.979) were all significantly lower in theophylline users. Additionally, the theophylline users also had lower risk of in-hospital death (OR 0.895, 95% CI 0.873-0.918) and need for mechanical ventilation (OR 0.972, 95% CI 0.949-0.997).

CONCLUSIONS

Theophylline use is associated with a lower risk of sepsis-related mortality in COPD patients. Pre-hospital theophylline use may be protective to COPD patients with sepsis.

Long-Term Risk of Cardiovascular Events in Patients With Chronic Kidney Disease Who Have Survived Sepsis: A Nationwide Cohort Study

BACKGROUND

Long-term cardiovascular outcomes after sepsis in patients with chronic kidney disease are not well known. We aimed to examine the risk of subsequent cardiovascular events in patients with chronic kidney disease discharged after hospitalization for sepsis in Taiwan.

METHODS AND RESULTS

Using complete claims data for patients with chronic kidney disease from Taiwan's National Health Insurance Research Database, we identified patients with sepsis who survived hospitalization between 2000 and 2010. Each sepsis survivor was propensity score-matched to one nonsepsis hospitalized control patient. Cox regression models were used to estimate the hazard ratios (HRs) of clinical outcomes, including major adverse cardiovascular events (myocardial infarction and ischemic stroke), hospitalization for heart failure, and all-cause death. Among 66 961 sepsis survivors, the incidence rates of all-cause mortality and major adverse cardiovascular events during the study period were 288.51 and 47.05 per 1000 person-years, respectively. In comparison with matched hospitalized nonsepsis control patients, sepsis survivors had greater risks of major adverse cardiovascular events (HR, 1.42; 95% CI, 1.37-1.47), myocardial infarction (HR, 1.39; 95% CI, 1.32-1.47), ischemic stroke (HR, 1.46; 95% CI, 1.40-1.52), hospitalization for heart failure (HR, 1.55; 95% CI, 1.51-1.59), and all-cause mortality (HR, 1.56; 95% CI, 1.54-1.58). The results remained unchanged in analyses of several subgroups of patients, and were similar in analyses accounting for the competing risk of death.

CONCLUSIONS

Our findings highlight the association of sepsis with a significantly increased long-term risk of cardiovascular events among survivors in the chronic kidney disease population.

Dual Antiplatelet Therapy and Clinical Outcomes after Coronary Drug-Eluting Stent Implantation in Patients on Hemodialysis

BACKGROUND AND OBJECTIVES

We aimed to investigate the benefits and risks of dual antiplatelet therapy (DAPT) after coronary drug-eluting stent (DES) implantation in patients undergoing hemodialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A nested case-control analysis of patients on hemodialysis after receipt of DES and DAPT treatment was conducted using data from Taiwan's National Health Insurance Research Database for the period 2007-2011. Cases of myocardial infarction or death within 1 year after DES implantation were matched one-to-one with control patients. Odds ratios were calculated to compare DAPT continuation with discontinuation. Additionally, a propensity score-adjusted 6-month landmark cohort analysis was also conducted to evaluate the long-term benefits and risks of prolonged (>6 months) compared with ≤6 months of DAPT use. The primary outcomes were death and myocardial infarction. The secondary outcomes were ischemic stroke, revascularization, and major bleeding.

RESULTS

In the nested case-control analysis, patients who continued DAPT had a lower rate of death or myocardial infarction within 1 year after receipt of a DES (adjusted odds ratio, 0.54; 95% confidence interval, 0.36 to 0.81; P=0.003), whereas this association became statistically nonsignificant when compared with patients who discontinued DAPT for the period between 6 and 12 months after receipt of a DES (adjusted odds ratio, 1.51; 95% confidence interval, 0.75 to 3.04). In the propensity score-adjusted cohort analysis, >6 months of DAPT use was not associated with different primary or secondary outcomes than shorter-term use.

CONCLUSIONS

Our findings support that the clinical effectiveness of extended DAPT in a hemodialysis population may be tempered after 6 months post-DES implantation.

Prevalence of Atrial Fibrillation and Antithrombotic Therapy in Hemodialysis Patients: Cross-Sectional Results of the Vienna InVestigation of AtriaL Fibrillation and Thromboembolism in Patients on HemoDIalysis (VIVALDI)

Background

Atrial fibrillation (AF) adds significant risk of stroke and thromboembolism in patients on hemodialysis (HD). The aim of this study was to investigate the prevalence of AF in a population-based cohort of HD patients and practice patterns of antithrombotic therapy for stroke prevention in AF.

Methods

The Vienna InVestigation of AtriaL fibrillation and thromboembolism in patients on hemodialysis (VIVALDI), an ongoing prospective observational cohort study, investigates the prevalence of AF and the risk of thromboembolic events in HD patients in Vienna, Austria. We analyzed cross-sectional data of 626 patients (63.4% men, median age 66 years, approx. 73% of HD patients in Vienna), who provided informed consent. A structured interview with each patient was performed, recent and archived ECGs were viewed and medical histories were verified with electronic records.

Results

The overall prevalence of AF was 26.5% (166 patients, 71.1% men, median age 72 years) of which 57.8% had paroxysmal AF, 3.0% persistent AF, 32.5% permanent AF, and 6.6% of patients had newly diagnosed AF. The median CHA₂DS₂-VASc Score was 4 [25^th-75^th percentile 3–5]. In multivariable analysis, AF was independently associated with age (odds ratio: 1.05 per year increase, 95% confidence interval: 1.03–1.07), male sex (1.7, 1.1–2.6), history of venous thromboembolism (2.0, 1.1–3.6), congestive heart failure (1.7, 1.1–2.5), history of or active cancer (1.5, 1.0–2.4) and time on HD (1.08 per year on HD, 1.03–1.13). Antithrombotic treatment was applied in 84.4% of AF patients (anticoagulant agents in 29.5%, antiplatelet agents in 33.7%, and both in 21.1%). In AF patients, vitamin-K-antagonists were used more often than low-molecular-weight heparins (30.1% and 19.9%).

Conclusions

The prevalence of AF is high amongst HD patients and is associated with age, sex, and distinct comorbidities. Practice patterns of antithrombotic treatment indicate a lack of consensus for stroke prevention in HD patients with AF.

Influence of Competing Risks on Estimating the Expected Benefit of Warfarin in Individuals with Atrial Fibrillation Not Currently Taking Anticoagulants: The Anticoagulation and Risk Factors in Atrial Fibrillation Study

OBJECTIVES

To provide greater understanding of the "real world" effect of anticoagulation on stroke risk over several years.

DESIGN

Cohort study.

SETTING

Anticoagulation and Risk Factors in Atrial Fibrillation Study community-based cohort.

PARTICIPANTS

Adults with nonvalvular atrial fibrillation (AF) between 1996 and 2003 (13,559).

MEASUREMENTS

All events were clinician adjudicated. Extended Cox regression with longitudinal warfarin exposure was used to estimate cause-specific hazard ratios (HRs) for thromboembolism and the competing risk event (all cause death). The Fine and Gray subdistribution regression approach was used to estimate this association while accounting for competing death events. As a secondary analysis, follow-up was limited to 1, 3, and 5 years.

RESULTS

The rate of death was much higher in the group not taking warfarin (8.1 deaths/100 person-years (PY)) than in the group taking warfarin (5.5 deaths/100 PY). The cause-specific HR indicated a large reduction in thromboembolism with warfarin use (adjusted HR = 0.57, 95% confidence interval (CI) = 0.50-0.65), although this association was substantially attenuated after accounting for competing death events (adjusted HR = 0.87, 95% CI = 0.77-0.99). In analyses limited to 1 year of follow-up, with fewer competing death events, the results for models that did and did not account for competing risks were similar.

CONCLUSION

Analyses accounting for competing death events may provide a more-realistic estimate of the longer-term stroke prevention benefits of anticoagulants than traditional noncompeting risk analyses for individuals with AF, particularly those who are not currently treated with anticoagulants.

Overcoming global challenges in stroke prophylaxis in atrial fibrillation: The role of non-vitamin K antagonist oral anticoagulants

Atrial fibrillation is the world's most common sustained cardiac arrhythmia and is associated with a significantly increased risk of stroke. The global burden of atrial fibrillation is rising, commensurate with the ageing population. Well-controlled vitamin K antagonist-based anticoagulation has been shown to reduce the risk of stroke secondary to atrial fibrillation by two-thirds. However, patients with atrial fibrillation have frequently been denied anticoagulation because of a variety of perceived risks related to bleeding, falls, chronological age, and poor compliance. Even when vitamin K antagonists are used, maximum benefit and safety are only delivered when high quality control of therapy (TTR > 70%) is achieved, which has proven remarkably difficult in many health-care systems and amongst many patient groups. The non-vitamin K antagonist oral anticoagulants (NOACs) offer solutions to many of the challenges of achieving widespread, safe, and effective anticoagulation for stroke prophylaxis in atrial fibrillation, yet their uptake into routine clinical practice remains variable. The evidence supporting their more widespread use to overcome the challenges of stroke prophylaxis for atrial fibrillation is reviewed in this article.

Effects of DPP-4 inhibitors on cardiovascular outcomes in patients with type 2 diabetes and end-stage renal disease

BACKGROUND

Recent clinical trials have evaluated the cardiovascular outcomes of dipeptidyl peptidase-4 (DPP-4) inhibitors in patients with type 2 diabetes mellitus (T2DM), but those with end-stage renal disease (ESRD) were ineligible for participation in these trials. We aimed to characterize the impact of DPP-4 inhibitors on major adverse cardiovascular events (MACEs) in patients with T2DM and ESRD undergoing chronic dialysis.

METHODS

This nationwide observational study utilized data from 3556 patients aged ≥20years with T2DM and ESRD who initiated treatment with DPP-4 inhibitors between 1 March 2009 and 31 June 2013, retrieved from Taiwan's National Health Insurance Research Database. Each DPP-4 inhibitor user was matched to a non-user control subject using propensity scores. The primary outcomes were all-cause mortality and MACEs (ischemic stroke and myocardial infarction). The secondary outcomes were hospitalization for heart failure and hypoglycemia. All subjects were followed until death or 31 December 2013.

RESULTS

Compared with non-users, DPP-4 inhibitor users had lower risks of all-cause mortality (hazard ratio [HR] 0.43, 95% confidence interval [CI] 0.39-0.47), MACEs (HR 0.76, 95% CI 0.65-0.90), and ischemic stroke (HR 0.77, 95% CI 0.61-0.97); the risks of myocardial infarction and hospitalization for heart failure and hypoglycemia did not differ. This treatment effect remained consistent in subgroup analyses according to age, sex, comorbidities, dialysis modality, and insulin use.

CONCLUSIONS

In this nationwide ESRD cohort, DPP-4 inhibitor use was associated with reduced risks of all-cause mortality and ischemic stroke.