Sex-Related Differences in the Clinical Events of Patients With Atrial Fibrillation - The Fushimi AF Registry

Visit-to-Visit Heart Rate Variability in the Prediction of Clinical Outcomes of Patients with Atrial Fibrillation

BACKGROUND

 Visit-to-visit heart rate variability (VVV-HR) has been associated with adverse cardiovascular outcomes. We aimed to determine the predictive value of VVV-HR for adverse clinical outcomes in patients with nonvalvular atrial fibrillation (AF).

METHODS

 We used data from a prospective multicenter AF registry of 27 hospitals in Thailand during 2014 to 2017. After the baseline visit, patients were followed up every 6 months until 3 years. VVV-HR was calculated from the standard deviation of heart rate data from baseline visit and every follow-up visit. VVV-HR was categorized into four groups according to the quartiles. Clinical outcomes were all-cause death, ischemic stroke/systemic embolism (SE), and heart failure. Cox proportional hazard models were used for multivariable analysis.

RESULTS

 There were a total of 3,174 patients (mean age: 67.7 years; 41.8% female). The incidence rates of all-cause death, ischemic stroke/SE, and heart failure were 3.10 (2.74-3.49), 1.42 (1.18-1.69), and 2.09 (1.80-2.42) per 100 person-years respectively. The average heart rate was 77.8 ± 11.0 bpm and the average of standard deviation of heart rate was 11.0 ± 5.9 bpm. VVV-HR Q4 was an independent predictor of all-cause death, ischemic stroke/SE, and heart failure with adjusted hazard ratios of 1.45 (95% confidence interval: 1.07-1.98), 2.02 (1.24-3.29), and 2.63 (1.75-3.96), respectively. VVV-HR still remained a significant predictor of clinical outcomes when analyzed based on coefficient of variation and variability independent of mean.

CONCLUSION

 VVV-HR is an independent predictor for adverse clinical outcomes in patients with AF. A J-curve appearance was demonstrated for the effect of VVV-HR on all-cause death.

Three-year outcomes of patients with non-valvular atrial fibrillation: the COOL-AF registry

BACKGROUND

Clinical outcomes of patients with non-valvular atrial fibrillation (AF) in Asian populations may be different from non-Asians. In this study, we aimed to determine the incidence of ischemic stroke/systemic embolism (SSE), major bleeding, and death, and the predictors for clinical outcomes in a contemporary Asian cohort of newly diagnosed AF patients.

METHODS

This is a prospective multicenter nationwide registry of patients with AF from 27 hospitals in Thailand. Baseline data and follow-up data were collected every 6 months until 3 years. Data collections included demographic, medical history, laboratory, and medication details. Clinical outcomes were SSE, major bleeding, and all-cause mortality. Incidence rates for each clinical outcome were calculated and presented as rate per 100 person-years. Univariate and multivariate analysis was performed to determine the independent predictors for clinical outcomes.

RESULTS

There was a total of 3405 patients: mean age was 67.8 ± 11.3 years, 1981 (58.2%) were male. During 30.8 ± 9.7 months follow-up, there was a total of 132 SSE (3.9%), 191 major bleeding (5.6%), and 357 all-cause deaths (10.5%). The incidence rates of SSE, major bleeding, and death were 1.56 (1.30-1.84), 2.26 (1.96-2.61), and 4.17 (3.33-4.25), per 100 person-years respectively. Independent predictors for clinical outcomes were age, type of AF, and the presence of comorbid conditions.

CONCLUSION

The incidence rate of SSE, major bleeding, and death remains high reflecting the unmet needs in AF management.

Predicting Heart Failure in Patients with Atrial Fibrillation: A Report from the Prospective COOL-AF Registry

BACKGROUND

This study aimed to determine risk factors and incidence rate and develop a predictive risk model for heart failure for Asian patients with atrial fibrillation (AF).

METHODS

This is a prospective multicenter registry of patients with non-valvular AF in Thailand conducted between 2014 and 2017. The primary outcome was the occurrence of an HF event. A predictive model was developed using a multivariable Cox-proportional model. The predictive model was assessed using C-index, D-statistics, Calibration plot, Brier test, and survival analysis.

RESULTS

There were a total of 3402 patients (average age 67.4 years, 58.2% male) with mean follow-up duration of 25.7 ± 10.6 months. Heart failure occurred in 218 patients during follow-up, representing an incidence rate of 3.03 (2.64-3.46) per 100 person-years. There were ten HF clinical factors in the model. The predictive model developed from these factors had a C-index and D-statistic of 0.756 (95% CI: 0.737-0.775) and 1.503 (95% CI: 1.372-1.634), respectively. The calibration plots showed a good agreement between the predicted and observed model with the calibration slope of 0.838. The internal validation was confirmed using the bootstrap method. The Brier score indicated that the model had a good prediction for HF.

CONCLUSIONS

We provide a validated clinical HF predictive model for patients with AF, with good prediction and discrimination values.

Outcomes of patients with atrial fibrillation with and without diabetes: A propensity score matching of the COOL-AF registry

BACKGROUND

To investigate the clinical outcomes of patients with non-valvular atrial fibrillation (NVAF) compared between those with and without diabetes mellitus (DM).

METHODS

We conducted a prospective multicenter nationwide registry for patients with NVAF from 27 hospitals in Thailand. Patients were followed-up every 6 months until 3 years. The outcome measurements were ischemic stroke (IS) or transient ischemic attack (TIA), major bleeding, and heart failure (HF). All reported events were confirmed by the adjudication committee. DM was diagnosed by history or laboratory data.

RESULTS

We studied 3402 patients. DM was diagnosed in 923 patients (27.1%). The average follow-up duration was 25.74 ± 10.57 months (7912 persons-year). The rate of IS/TIA, major bleeding, and HF was 1.42, 2.11, and 3.03 per 100 person-years. Patients with DM had a significantly increased risk of IS/TIA, major bleeding, and HF. After adjusting for age, gender, comorbid conditions, and the use of oral anticoagulant (OAC) using propensity score matching, DM remained a significant predictor of ischemic stroke/TIA, major bleeding and HF with Hazard ratio and 95% confidence interval of 1.67 (1.02, 2.73), 1.65 (1.13, 2.40), and 1.87 (1.34, 2.59), respectively. The net clinical benefit of OAC was more pronounced in DM patients (0.88 events per 100 person-years) than in those without DM (-0.73 events per 100 person-years).

CONCLUSIONS

DM increases the risk of adverse clinical outcomes in NVAF patients. The benefit of OAC outweighs the risk in DM patients.

Influence of gender on the clinical outcomes of Asian non-valvular atrial fibrillation patients: insights from the prospective multicentre COOL-AF registry

OBJECTIVE

To determine the effect of gender on clinical outcomes of Asian non-valvular atrial fibrillation patients.

DESIGN

This is a cohort study.

SETTING

27 university and regional hospitals in Thailand.

PARTICIPANTS

Patients with non-valvular atrial fibrillation.

PRIMARY AND SECONDARY OUTCOMES MEASURES

The clinical outcomes were ischaemic stroke/transient ischaemic attack (TIA), major bleeding, intracerebral haemorrhage (ICH), heart failure and death. Follow-up data were recorded every 6 months until 3 years. Differences in clinical outcomes between males and females were determined. Multivariate analysis was performed to assess the effect of gender on clinical outcomes. Survival analysis and log-rank test were performed to determine the time-dependent effect of clinical outcomes, and the difference between males and females. Effect of oral anticoagulant (OAC) on outcomes and net clinical benefit of OAC was assessed. The analysis was performed both for the whole dataset and propensity score matching with multiple imputation.

RESULTS

A total of 3402 patients (mean age: 67.4±11.3 years; 58.2% male) were included. Average follow-up duration 25.7±10.6 months (7192.6 persons-year). Rate of ischaemic stroke/TIA, major bleeding, ICH, heart failure and death were 1.43 (1.17-1.74), 2.11 (1.79-2.48), 0.70 (0.52-0.92), 3.03 (2.64-3.46) and 3.77 (3.33-4.25) per 100 person-years. Females had increased risk for ischaemic stroke/TIA and heart failure and males had increased risk for major bleeding and ICH. Ischaemic stroke/TIA risk in females and major bleeding and ICH risk in males remained even after correction for age, comorbid conditions and anticoagulation treatment. OAC reduced the risk of ischaemic stroke/TIA in males and females, and markedly increased the risk of major bleeding and ICH in males.

CONCLUSIONS

Females had a higher risk of ischaemic stroke/TIA and heart failure, and a lower risk of major bleeding and ICH compared with males. OAC reduced risk of ischaemic stroke/TIA in females, and markedly increased risk of major bleeding and ICH in males.

Age-Related Clinical Outcomes of Patients with Non-Valvular Atrial Fibrillation: Insights from the COOL-AF Registry

PURPOSE

We aimed to compare the rate of clinical outcomes among three age groups (<65, 65-74, and ≥75 years) of adult patients with non-valvular atrial fibrillation (NVAF).

PATIENTS AND METHODS

We prospectively enrolled NVAF patients from 27 Thailand medical centers. The following were collected at baseline: demographic data, risk factors, comorbid conditions, laboratory data, and medications. The clinical outcomes were ischemic stroke (IS) or transient ischemic attack (TIA), major bleeding (MB), intracerebral hemorrhage (ICH), heart failure (HF), and death. All events were adjudicated. Patients were categorized according to age group into three groups; age <65, 65-74, and ≥75 years.

RESULTS

Among the 3402 patients that were enrolled during 2014-2017, the mean age was 67.4±11.3 years, and 2073 (60.9%) were older. The average follow-up was 25.7±10.6 months. Oral anticoagulants were given in 75.4% of patients (91.1% of OAC was warfarin). The incidence rate of IS/TIA, MB, ICH, HF, and death was 1.43 (1.17-1.74), 2.11 (1.79-2.48), 0.70 (0.52-0.92), 3.03 (2.64-3.46), and 3.77 (3.33-4.24) per 100 person-years, respectively. The risk of IS/TIA, MB, ICH, HF, and death increased with age both before and after adjustment for potential confounders. Even though OAC reduced the risk of IS/TIA, it increased the risk of MB. Net clinical benefit (NCB) analysis favored oral anticoagulant (OAC) in the high-risk subset of older adults.

CONCLUSION

Older adult NVAF patients had a significantly increased risk of IS/TIA, MB, ICH, HF, and death compared to younger NVAF before and after adjustment for potential confounders. Strategies to reduce overall risk, including OAC use and choice and integrated care, should be implemented.

Atrial fibrillation and stroke prevention: state of the art-epidemiology and pathophysiology: new risk factors, concepts and controversies

Atrial fibrillation (AF) increases the risk of thromboembolism, and risk assessment for thromboembolism is necessary for the management of AF patients. CHADS2 and CHA2DS2-VASc scores have been adopted in international guidelines for AF management, but the significance of each risk factor included in these risk scores are sometimes controversial, and the performance of these scores is only modest. There are several other risk factors not included in the scores such as renal dysfunction, low body weight, type of AF (paroxysmal or non-paroxysmal) as well as echocardiographic parameters and blood biomarkers, and physicians should assess patients risk in an integrated manner.

Optimal INR level in elderly and non-elderly patients with atrial fibrillation receiving warfarin: a report from the COOL-AF nationwide registry in Thailand

BACKGROUND

Asian population are at increased risk of bleeding during the warfarin treatment, so the recommended optimal international normalized ratio (INR) level may be lower in Asians than in Westerners. The aim of this prospective multicenter study was to determine the optimal INR level in Thai patients with non-valvular atrial fibrillation (NVAF).

METHODS

Patients with NVAF who were on warfarin for stroke prevention were recruited from 27 hospitals in the nationwide COOL-AF registry in Thailand. We collected demographic data, medical history, risk factors for stroke and bleeding, concomitant disease, electrocardiogram and laboratory data including INR and antithrombotic medications. Outcome measurements included ischemic stroke/transient ischemic attack (TIA) and major bleeding. Optimal INR level was assessed by the calculation of incidence density for six INR ranges (< 1.5, 1.5-1.99, 2-2.49, 2.5-2.99, 3-3.49, and ≥ 3.5).

RESULTS

A total of 2, 232 patients were included. The mean age of patients was 68.5 ± 10.6 years. The mean follow-up duration was 25.7 ± 10.6 months. There were 63 ischemic stroke/TIA and 112 major bleeding events. The lowest prevalence of ischemic stroke/TIA and major bleeding events occurred within the INR range of 2.0-2.99 for patients < 70 years and 1.5-2.99 for patients ≥ 70 years.

CONCLUSIONS

The INR range associated with the lowest risk of ischemic stroke/TIA and bleeding in the Thai population was 2.0-2.99 for patients < 70 years and 1.5-2.99 for patients ≥ 70 years. The rates of major bleeding and ischemic stroke/TIA were both higher than the rates reported in Western population.

Poor Time in Therapeutic Range Control is Associated with Adverse Clinical Outcomes in Patients with Non-Valvular Atrial Fibrillation: A Report from the Nationwide COOL-AF Registry

BACKGROUND

Warfarin remains the most commonly used oral anticoagulant (OAC) in Thailand for stroke prevention among patients with non-valvular atrial fibrillation (NVAF). The aim of this study was to investigate the relationship between time in therapeutic range (TTR) after warfarin initiation and clinical outcomes of NVAF.

METHODS

TTR was calculated by the Rosendaal method from international normalized ratio (INR) data acquired from a nationwide NVAF registry in Thailand. Patients were followed-up every six months. The association between TTR and clinical outcomes was analyzed.

RESULTS

There was a total of 2233 patients from 27 hospitals. The average age was 68.4 ± 10.6 years. The average TTR was 53.56 ± 26.37%. Rates of ischemic stroke/TIA, major bleeding, ICH, and death were 1.33, 2.48, 0.76, and 3.3 per 100 person-years, respectively. When patients with a TTR < 65% were compared with those with TTR ≥ 65%, the adjusted hazard ratios (aHR) for the increased risks of ischemic stroke/TIA, major bleeding, ICH, and death were 3.07, 1.90, 2.34, and 2.11, respectively.

CONCLUSION

Poor TTR control is associated with adverse clinical outcomes in patients with NVAF who were on warfarin. Efforts to ensure good TTR (≥65%) after initiation of warfarin are mandatory to minimize the risk of adverse clinical outcomes.

Female sex as a risk factor for ischaemic stroke varies with age in patients with atrial fibrillation

Objectives

Female sex is an inconsistent ischaemic stroke risk factor in patients with atrial fibrillation (AF). We hypothesised that the ischaemic stroke risk varies with age among women compared with men.

Methods

We retrieved the patients with newly diagnosed AF during 2001–2013 from Taiwan’s National Health Insurance Research Database. Patients with missing information, age <20 years, history of valvular heart disease and surgery, rheumatic heart disease, hyperthyroidism or anticoagulation and/or antiplatelet use were excluded. Propensity score matching (PSM) included patient comorbidities, medications and index date stratified by age and sex groups. Primary outcome was defined as ischaemic stroke at follow-up.

Results

After exclusion criteria, 87 369 men and 71 853 women remained for analysis (aged 73.1±14.4 years). After 1:1 PSM, we included 59 583 men (aged 73.5±13.7 years) and 59 583 women (aged 73.4±13.8 years) for analysis. We also stratified patients by age. The ischaemic stroke risk varied with age in women compared with men: lower in the ≤55 years (subdistribution HR (SHR)=0.75, 95% CI 0.62 to 0.90) and 56–65 years (SHR=0.87, 95% CI 0.78 to 0.98) groups, neutral in the 66–75 years group (SHR=1.01, 95% CI 0.94 to 1.08) and adverse in the >75 years group (SHR=1.14, 95% CI 1.09 to 1.19).

Conclusions

The female/male ischaemic stroke risk ratio varied with age. Only women aged >75 years had a higher risk, whereas women aged <65 years had a lower risk compared with men. These findings challenge the ‘sex category’ component of the CHA2DS2-VASc score, used to make decision regarding anticoagulation treatment in AF patients.