Modifiable lifestyle factors and lifetime risk of atrial fibrillation: longitudinal data from the Korea NHIS-HealS and UK Biobank cohorts.

BACKGROUND: The reason for higher incidence of atrial fibrillation (AF) in Europe compared with East Asia is unclear. We aimed to investigate the association between modifiable lifestyle factors and lifetime risk of AF in Europe and East Asia, along with race/ethnic similarities and disparities. METHODS: 1:1 propensity score matched pairs of 242,763 East Asians and 242,763 White Europeans without AF were analyzed. Modifiable lifestyle factors considered were blood pressure, body mass index, cigarette smoking, diabetes, alcohol consumption, and physical activity, categorized as non-adverse or adverse levels. Lifetime risk of AF was estimated from the index age of 45 years to the attained age of 85 years, accounting for the competing risk of death. RESULTS: The overall lifetime risk of AF was higher in White Europeans than East Asians (20.9% vs 15.4%, p < 0.001). The lifetime risk of AF was similar between the two races in individuals with non-adverse lifestyle factor profiles (13.4% vs 12.9%, p = 0.575), whereas it was higher in White Europeans with adverse lifestyle factor profiles (22.1% vs 15.8%, p < 0.001). The difference in the lifetime risk of AF between the two races increased as the burden of adverse lifestyle factors worsened (1 adverse lifestyle factor; 4.3% to ≥ 3 adverse lifestyle factors; 11.2%). Compared with East Asians, the relative risk of AF in White Europeans was 23% and 62% higher for one (hazard ratio [HR] 1.23, 95% confidence interval [CI] 1.16-1.29) and ≥ 3 adverse lifestyle factors (HR 1.62, 95% CI 1.51-1.75), respectively. CONCLUSIONS: The overall higher lifetime risk of AF in White Europeans compared with East Asians might be attributable to adverse lifestyle factors. Adherence to healthy lifestyle factors was associated with the lifetime risk of AF of about 1 in 8 regardless of race/ethnicity.

Efficacy and Safety of Triple Therapy of Telmisartan/Amlodipine/Rosuvastatin in Patients with Dyslipidemia and Hypertension: A Multicenter Randomized Clinical Trial.

Background: Hypertension and dyslipidemia significantly contribute to cardiovascular disease development. Their coexistence poses challenges in managing multiple medications, influencing treatment adherence. Objective: This study aimed to assess the efficacy and safety of a combined treatment approach using a fixed-dose combination therapy. Methods: This multicenter, 8-week, randomized, double-blind, Phase IV trial was named Telmisartan/Amlodipine/Rosuvastatin from Samjin Pharmaceuticals and evaluated the efficacy and safety of fixed-dose combination treatment in patients with essential hypertension and dyslipidemia. They were randomly assigned to 2 fixed-dose combination therapy groups, telmisartan 40 mg/amlodipine 5 mg/rosuvastatin 10 mg (TEL/ALD/RSV) or amlodipine 5 mg/atorvastatin 10 mg (ALD/ATV) after washout/run-in period. The primary outcomes were the change in mean sitting systolic blood pressure and the percentage change of LDL-C after 8 weeks of medical treatment. Adverse drug reactions and events were assessed. Results: Of a total of 304 patients who underwent screening, 252 were randomized to the TEL/ALD/RSV group (125 patients) and the ALD/ATV group (127 patients). The mean (SD) ages of the TEL/ALD/RSV group and the ALD/ATV group were 67.4 (11.3) and 68.2 (10.6) years, respectively (P = 0.563). The least-squares mean (SE) in mean sitting systolic blood pressure changes between the 2 groups were -16.27 (0.93) mm Hg in the TEL/ALD/RSV group, -6.85 (0.92) mm Hg in the ALD/ATV group (LSM difference = -9.42 mm Hg; 95% CI, -11.99 to -6.84; P < .001). For LDL-C level changes, a significant difference was noted between the 2 groups: -50.03% (1.18%) in the TEL/ALD/RSV group, -39.60% (1.17%) in the ALD/ATV group (LSM difference = -10.43%; 95% CI, -13.70 to -7.16; P < .001). No severe adverse events were observed. Conclusions: TEL/ALD/RSV proved to be more efficient than ALD/ATV in lowering blood pressure and reducing LDL-C levels among patients with hypertension and dyslipidemia, with no notable safety concerns. (Curr Ther Res Clin Exp. 2024; XX:XXX-XXX). ClinicalTrials.gov identifier: NCT03860220.

Early Rhythm Control Therapy for Atrial Fibrillation in Low-Risk Patients : A Nationwide Propensity Score-Weighted Study.

BACKGROUND: Rhythm control is associated with lower risk for adverse cardiovascular outcomes compared with usual care among patients recently diagnosed with atrial fibrillation (AF) with a CHA2DS2-VASc score of approximately 2 or greater in EAST-AFNET 4 (Early Treatment of Atrial Fibrillation for Stroke Prevention Trial). OBJECTIVE: To investigate whether the results can be generalized to patients with low stroke risk. DESIGN: Population-based cohort study. SETTING: Nationwide claims database of the Korean National Health Insurance Service. PARTICIPANTS: 54 216 patients with AF having early rhythm control (antiarrhythmic drugs or ablation) or rate control therapy that was initiated within 1 year of the AF diagnosis. MEASUREMENTS: The effect of early rhythm control on the primary composite outcome of cardiovascular death, ischemic stroke, hospitalization for heart failure, or myocardial infarction was compared between eligible and ineligible patients for EAST-AFNET 4 (CHA2DS2-VASc score, approximately 0 to 1) using propensity overlap weighting. RESULTS: In total, 37 557 study participants (69.3%) were eligible for the trial (median age, 70 years; median CHA2DS2-VASc score, 4), among whom early rhythm control was associated with lower risk for the primary composite outcome than rate control (hazard ratio, 0.86 [95% CI, 0.81 to 0.92]). Among the 16 659 low-risk patients (30.7%) who did not meet the inclusion criteria (median age, 54 years; median CHA2DS2-VASc score, 1), early rhythm control was consistently associated with lower risk for the primary outcome (hazard ratio, 0.81 [CI, 0.66 to 0.98]). No significant differences in safety outcomes were found between the rhythm and rate control strategies regardless of trial eligibility. LIMITATION: Residual confounding. CONCLUSION: In routine clinical practice, the beneficial association between early rhythm control and cardiovascular complications was consistent among low-risk patients regardless of trial eligibility. PRIMARY FUNDING SOURCE: The Ministry of Health and Welfare and the Ministry of Food and Drug Safety, Republic of Korea.

Association of Thymidylate Synthase (TS) Gene Polymorphisms with Incidence and Prognosis of Coronary Artery Disease.

Coronary artery disease (CAD) is a prevalent cardiovascular condition characterized by the accumulation of plaque within coronary arteries. While distinct features of CAD have been reported, the association between genetic factors and CAD in terms of biomarkers was insufficient. This study aimed to investigate the connection between genetic factors and CAD, focusing on the thymidylate synthase (TS) gene, a gene involved in DNA synthesis and one-carbon metabolism. TS plays a critical role in maintaining the deoxythymidine monophosphate (dTMP) pool, which is essential for DNA replication and repair. Therefore, our research targeted single nucleotide polymorphisms that could potentially impact TS gene expression and lead to dysfunction. Our findings strongly associate the TS 1100T>C and 1170A>G genotypes with CAD susceptibility. We observed that TS 1100T>C polymorphisms increased disease susceptibility in several groups, while the TS 1170A>G polymorphism displayed a decreasing trend for disease risk when interacting with clinical factors. Furthermore, our results demonstrate the potential contribution of the TS 1100/1170 haplotypes to disease susceptibility, indicating a synergistic interaction with clinical factors in disease occurrence. Based on these findings, we propose that polymorphisms in the TS gene had the possibility of clinically useful biomarkers for the prevention, prognosis, and management of CAD in the Korean population.

Effectiveness and Safety of Anticoagulation Therapy in Frail Patients With Atrial Fibrillation.

BACKGROUND: Frail patients with atrial fibrillation (AF) are less likely to receive anticoagulation than nonfrail patients with AF despite frailty being associated with poorer clinical outcomes including stroke. Using a population-based cohort, we sought to assess the effectiveness and safety of oral anticoagulants (OACs) in frail patients with AF. METHODS: This retrospective cohort study analyzed 83 635 patients aged at least 65 years with AF and frailty (≥5 Hospital Frailty Risk Score) between January 1, 2013 and December 31, 2016 from the Korean National Health Insurance Service database. To account for the differences between patients receiving OAC or not and across different OAC regimens, propensity score-weighting was used. Net adverse clinical event, defined as the first event of ischemic stroke, major bleeding, or cardiovascular death, was compared. In addition, each individual outcome was examined separately. RESULTS: In the study population (57.1% women; mean age, 78.5±7.2 years), a total of 14 968 net adverse clinical event, 3718 ischemic stroke, 5536 major bleeding, and 6188 cardiovascular death occurred. In comparison with no OAC use, OAC use was associated with lower risks of net adverse clinical event (hazard ratio, 0.78 [95% CI, 0.75-0.82]), ischemic stroke (hazard ratio, 0.91 [95% CI, 0.86-0.97]), and cardiovascular death (hazard ratio, 0.52 [95% CI, 0.49-0.55]), but no difference was observed for major bleeding (hazard ratio, 1.02 [95% CI, 0.95-1.10]). Compared with warfarin, all four individual direct OAC were associated with decreased risks of net adverse clinical event, ischemic stroke, major bleeding, and cardiovascular death. The associations for OAC use (compared to no OAC use) or direct OAC use (compared to warfarin) with favorable outcomes were more prominent in individuals with a higher CHA2DS2-VASc score of at least 3. CONCLUSIONS: Among frail patients with AF, OAC treatment was associated with a positive net clinical outcome. Direct OACs provided lower incidences of stroke, bleeding, and mortality, compared with warfarin.

Association of rhythm control with incident dementia among patients with atrial fibrillation: a nationwide population-based cohort study.

BACKGROUND: Atrial fibrillation (AF) increases the risk of dementia, and catheter ablation of AF may be associated with a lower risk of dementia. We investigated the association of a rhythm-control strategy for AF with the risk of dementia, compared with a rate-control strategy. METHODS: This population-based cohort study included 41,135 patients with AF on anticoagulation who were newly treated with rhythm-control (anti-arrhythmic drugs or ablation) or rate-control strategies between 1 January 2005 and 31 December 2015 from the Korean National Health Insurance Service database. The primary outcome was all-cause dementia, which was compared using propensity score overlap weighting. RESULTS: In the study population (46.7% female; median age: 68 years), a total of 4,039 patients were diagnosed with dementia during a median follow-up of 51.7 months. Rhythm control, compared with rate control, was associated with decreased dementia risk (weighted incidence rate: 21.2 versus 25.2 per 1,000 person-years; subdistribution hazard ratio [sHR] 0.86, 95% confidence interval [CI] 0.80-0.93). The associations between rhythm control and decreased dementia risk were consistently observed even after censoring for incident stroke (sHR 0.89, 95% CI 0.82-0.97) and were more pronounced in relatively younger patients and those with lower CHA2DS2-VASc scores. Among dementia subtypes, rhythm control was associated with a lower risk of Alzheimer's disease (sHR 0.86, 95% CI 0.79-0.95). CONCLUSIONS: Among anticoagulated patients with AF, rhythm control was associated with a lower risk of dementia, compared with rate control. Initiating rhythm control in AF patients with fewer stroke risk factors might help prevent subsequent dementia.

Increased risk of ischemic stroke and systemic embolism in hyperthyroidism-related atrial fibrillation: A nationwide cohort study.

BACKGROUND: We aimed to evaluate the long-term risk of ischemic stroke/systemic embolism of hyperthyroidism-related AF. METHODS: This retrospective population-based cohort study included records of 1,034,099 atrial fibrillation patients between 2005 and 2016 from the Korean National Health Insurance Service database. After exclusion, we identified 615,724 oral anticoagulation-naïve patients aged ≥18 years with new-onset non-valvular atrial fibrillation, of whom 20,773 had hyperthyroidism-related atrial fibrillation. After 3:1 propensity score matching, ischemic stroke and systemic embolism occurrences were compared between hyperthyroidism-related and non-hyperthyroidism-related ("nonthyroidal") atrial fibrillation patients. RESULTS: After exclusion, we identified 615,724 oral anticoagulation-naïve AF patients of whom 20,773 had hyperthyroidism-related AF. Median follow-up duration was 5.9 years. Hyperthyroidism-related AF patients had significantly higher risks of ischemic stroke and systemic embolism than nonthyroidal AF patients (1.83 vs 1.62 per 100-person year, hazard ratio[HR], 1.13; 95% confidence interval[CI], 1.07 to 1.19; P < 0.001). This risk was 36% higher in hyperthyroidism-related than in nonthyroidal AF patients within 1 year of atrial fibrillation diagnosis (3.65 vs 2.67 per 100-person year, HR, 1.36; 95% CI, 1.24 - 1.50; P < 0.001). This difference was also observed in the CHA2DS2-VASc score subgroup analysis. The risk of ischemic stroke and systemic embolism significantly decreased in patients treated for hyperthyroidism (HR, 0.64; 95% CI, 0.58 to 0.70; P < 0.001). CONCLUSIONS: Hyperthyroidism-related AF patients have high risks of ischemic stroke and systemic embolism like nonthyroidal AF, especially when initially diagnosed. This risk is reduced by treating hyperthyroidism.

Risk of sick sinus syndrome in patients diagnosed with atrial fibrillation: A population-based cohort.

BACKGROUND: Sinoatrial node dysfunction and atrial fibrillation (AF) frequently coexist and interact with each other, often to initiate and perpetuate each other. OBJECTIVE: To determine the effect of AF on the incidence and risk of sick sinus syndrome (SSS). METHODS: The association of incident AF with the development of incident SSS was assessed from 2004 to 2014 in 302 229 SSS- and pacemaker-free subjects aged ≥60 years in the Korea National Health Insurance Service-Senior cohort. RESULTS: During an observation period of 1 854 800 person-years, incident AF was observed in a total of 12 797 subjects (0.69%/year). The incidence of SSS was 3.4 and 0.2 per 1000 person-years in the propensity score-matched incident AF and no-AF groups, respectively. After adjustment, the significantly increased risk of SSS was observed in the incident AF group, with a hazard ratio (HR) of 13.4 (95% confidence interval [CI]: 8.4-21.4). This finding was consistently observed after censoring for heart failure (HR: 16.0; 95% CI: 9.2-28.0) or heart failure/myocardial infarction (HR: 16.6; 95% CI: 9.3-29.7). Incident AF also was associated with an increased risk of pacemaker implantation related with both SSS (HR: 21.8; 95% CI: 8.7-18.4) and atrioventricular (AV) block (HR: 9.5; 95% CI: 4.9-18.4). These results were consistent regardless of sex and comorbidities. CONCLUSION: Incident AF was associated with more than 10 times increased risk of SSS in an elderly population regardless of comorbidities. The risk of pacemaker implantations related with both sinus node dysfunction and AV block was increased in the elderly population with incident AF.

Association of anticoagulant therapy with risk of dementia among patients with atrial fibrillation.

AIMS: To investigate the risk of dementia in atrial fibrillation (AF) patients treated with different oral anticoagulants (OACs). METHODS AND RESULTS: This observational, population-based cohort study enrolled 53 236 dementia-free individuals with non-valvular AF who were aged ≥50 years and newly prescribed OACs from 1 January 2013 to 31 December 2016 from the Korean National Health Insurance Service database. Propensity score matching was used to compare the rates of dementia between users of non-vitamin K antagonist oral anticoagulant (NOAC) (dabigatran, rivaroxaban, and apixaban) and warfarin and to compare each individual NOAC with warfarin. Propensity score weighting analyses were also performed. In the study population (41.3% women; mean age: 70.7 years), 2194 had a diagnosis of incident dementia during a mean follow-up of 20.2 months. Relative to propensity-matched warfarin users, NOAC users tended to be at lower risk of dementia [hazard ratio (HR) 0.78, 95% confidence interval (CI) 0.69-0.90]. When comparing individual NOACs with warfarin, all the three NOACs were associated with lower dementia risk. In pairwise comparisons among NOACs, rivaroxaban was associated with decreased dementia risk, compared with dabigatran (HR 0.83, 95% CI 0.74-0.92). Supplemental propensity-weighted analyses showed consistent protective associations of NOACs with dementia relative to warfarin. The associations were consistent irrespectively of age, sex, stroke, and vascular disease and more prominent in standard dose users of NOAC. CONCLUSION: In this propensity-matched and -weighted analysis using a real-world population-based cohort, use of NOACs was associated with lower dementia risk than use of warfarin among non-valvular AF patients initiating OAC treatment.

Frailty and the Effect of Catheter Ablation in the Elderly Population With Atrial Fibrillation　- A Real-World Analysis.

BACKGROUND: It is unclear whether catheter ablation is beneficial for frail elderly patients with atrial fibrillation (AF). This study evaluated the effect of ablation on outcomes in frail elderly patients with AF.Methods and Results:From the Korean National Health Insurance Service database, 194,928 newly diagnosed AF patients were treated with ablation or medical therapy (rhythm or rate control) between 2005 and 2015. Among these patients, the study included 1,818 (ablation; n=119) frail and 1,907 (ablation; n=230) non-frail elderly (≥75 years) patients. Propensity score matching was used to correct for differences between groups. During 28 months (median) follow up, the risk of all-cause death, composite outcome (all-cause death, heart failure admission, stroke/systemic embolism, and sudden cardiac arrest), and each outcome did not change after ablation in frail elderly patients. However, in non-frail elderly patients, ablation was associated with a lower risk of all-cause death (3.5 and 6.2 per 100 person-years; hazard ratio [HR] 0.48; 95% confidence interval [CI] 0.30-0.79; P=0.004), and composite outcome (6.9 and 11.2 per 100 person-years; HR 0.54; 95% CI 0.38-0.75; P<0.001). CONCLUSIONS: Ablation may be associated with a lower risk of death and composite outcome in non-frail elderly, but the beneficial effect of ablation was not significant in frail elderly patients with AF. The effect of frailty on the outcome of ablation should be evaluated in further studies.

Impact of abdominal obesity on outcomes of catheter ablation in Korean patients with atrial fibrillation.

BACKGROUND: Effects of abdominal obesity on outcomes of atrial fibrillation (AF) ablation remains ill-defined. Here, we evaluated the impact of abdominal obesity on the long-term efficacy and safety of catheter AF ablation among Korean patients. METHODS: We utilised the Korean National Health Insurance Service database to identify patients who underwent AF ablation. Abdominal obesity was defined as waist circumference ≥90 cm (males) and ≥85 cm (females). The primary endpoint was AF recurrence and secondary endpoints were ischaemic stroke, intracranial haemorrhage and death. Additionally, safety endpoints of peri-procedural complications were studied. RESULTS: Among 5397 patients (median age 58 [IQR 51-65] years; 23.6% females), abdominal obesity was present in 1759 (32.6%). The rate of AF recurrence was not statistically different between the groups at 1-year (10.3 vs 8.7 events/100-PYs, P = .078), though abdominal obesity was associated with significantly higher rates of AF recurrence at 3-year (7.6 vs 6.3 events/100-PYs, P = .008) and 6-year (6.3 vs 5.2 events/100-PYs, P = .004) follow-ups. Kaplan-Meier survival analysis found significantly higher rates of AF recurrence in patients with obesity based on body mass index (BMI) and waist circumference (log-rank for trend P = .006). Using multivariable regression analysis, obesity by both BMI and waist circumference was an independent predictor for AF recurrence (HR 1.21 [95% CI, 1.05-1.40]), after accounting for other risk factors. There was a trend for increased rates of ischaemic stroke at 3-year and 6-year follow-ups in patients with abdominal obesity. Furthermore, this group of patients had a greater rate of intracranial haemorrhage. All-cause death was comparable between both groups. Total peri-procedural complications were not associated with abdominal obesity. CONCLUSION: Abdominal obesity as indicated by waist circumference was associated with a greater burden of concomitant diseases and an independent risk factor for long-term redo AF intervention following catheter ablation but had no effects on total peri-procedural complications.

Less dementia after catheter ablation for atrial fibrillation: a nationwide cohort study.

AIMS: Accumulating evidence shows that atrial fibrillation (AF) is associated with an increased risk of dementia. Catheter ablation for AF prolongs the duration of sinus rhythm, thereby improving the quality of life. We investigated the association of catheter ablation for AF with the occurrence of dementia. METHODS AND RESULTS: Using the Korean National Health Insurance Service database, among 194 928 adults with AF treated with ablation or medical therapy (antiarrhythmic or rate control drugs) between 1 January 2005 and 31 December 2015, we studied 9119 patients undergoing ablation and 17 978 patients managed with medical therapy. The time-at-risk was counted from the first medical therapy, and ablation was analysed as a time-varying exposure. Propensity score-matching was used to correct for differences between the groups. During a median follow-up of 52 months, compared with patients with medical therapy, ablated patients showed lower incidence and risk of overall dementia (8.1 and 5.6 per 1000 person-years, respectively; hazard ratio 0.73, 95% confidence interval 0.58-0.93). The associations between ablation and dementia risk were consistently observed after additionally censoring for incident stroke (hazard ratio 0.76, 95% confidence interval 0.61-0.95) and more pronounced in cases of ablation success whereas no significant differences observed in cases of ablation failure. Ablation was associated with lower risks of dementia subtypes including Alzheimer's disease and vascular dementia. CONCLUSION: In this nationwide cohort of AF patients treated with catheter ablation or medical therapy, ablation was associated with decreased dementia risk. This relationship was evident after censoring for stroke and adjusting for clinical confounders.

The optimal drug adherence to maximize the efficacy and safety of non-vitamin K antagonist oral anticoagulant in real-world atrial fibrillation patients.

AIMS: To investigate the association between adherence to non-vitamin K antagonist oral anticoagulant (NOAC) and clinical outcomes and to determine the optimal cut-off level of NOAC adherence among patients with atrial fibrillation (AF). METHODS AND RESULTS: Using the Korean National Health Insurance Service database, we identified 96 197 patients with non-valvular AF who initiated NOAC or warfarin in 2013-16. We compared clinical outcomes between adherent [proportion of days covered (PDC) ≥80%] vs. non-adherent (PDC <80%) NOAC users, and further with warfarin users. We assessed the outcomes according to different levels of adherence. The proportion of adherent NOAC users was 64.0%. Compared with non-adherent NOAC users, adherent NOAC users were at lower risks of ischaemic stroke/systemic embolism (SE) [adjusted hazard ratio (aHR) 0.73, 95% confidence interval (CI) 0.69-0.79], and myocardial infarction (aHR 0.82, 95% CI 0.72-0.93), whereas there was no significant risk alteration for major bleeding (aHR 1.01, 95% CI 0.91-1.11). Compared with warfarin, non-adherent NOAC use failed to have better efficacy against ischaemic stroke/SE (aHR 0.99, 95% CI 0.93-1.05) and rather had increased risk of myocardial infarction (aHR 1.13, 95% CI 1.03-1.25). In NOAC users, the risks of adverse outcomes decreased according to gradual increase of adherence rates with the lowest risks in ≥90%, except for major bleeding in which there were no significant associations. CONCLUSIONS: In an adherence level-dependent fashion, adherent use of NOAC showed better clinical outcomes without increasing bleeding risk. Maintaining ≥90% of adherence optimizes effectiveness of NOAC therapy without compromising its safety.

Clinical features differentiating Takotsubo cardiomyopathy in the peripartum period from peripartum cardiomyopathy.

There are some similarities in clinical features between Takotsubo cardiomyopathy during the peripartum period (PTCM) and peripartum cardiomyopathy (PPCM). Both conditions present as acute heart failure and decreased left ventricular (LV) ejection fraction in the peripartum period in previously heart-healthy women. The present study aimed to evaluate the differences in clinical features and outcomes between PTCM and PPCM. Between January 2004 and December 2016, 37 consecutive patients who demonstrated LV dysfunction during the peripartum period without previous heart disease were recruited retrospectively. The clinical, laboratory, and echocardiographic data of these patients were comprehensively reviewed. Twenty-one (57%) and 16 (43%) patients were classified into PPCM and PTCM groups, respectively, based on echocardiographic findings. The initial LV ejection fraction did not differ significantly between the 2 groups. However, all patients with PTCM showed complete recovery of LV ejection fraction at the 1-month follow-up. However, among 20 patients with PPCM who underwent 1-month echocardiography, only 6 (30%) showed complete recovery of LV ejection fraction at the 1-month follow-up. At the 12-month follow-up, only 10 patients showed complete recovery of LV ejection fraction. The incidence of PTCM was much higher than expected. Although LV dysfunction was similar at the initial diagnosis, the prognosis of LV recovery was more favorable in PTCM than in PPCM. Therefore, physicians should differentiate these two diseases entities, although they have several similarities in acute LV dysfunction.

Risk of dementia in stroke-free patients diagnosed with atrial fibrillation: data from a population-based cohort.

AIMS: Atrial fibrillation (AF) is generally regarded as a risk factor for dementia, though longitudinal studies assessing the association between AF and dementia have shown inconsistent results. This study aimed to determine the effect of AF on the risk of developing dementia using a longitudinal, community-based, and stroke-free elderly cohort. METHODS AND RESULTS: The association of incident AF with the development of incident dementia was assessed from 2005 to 2012 in 262 611 dementia- and stroke-free participants aged ≥60 years in the Korea National Health Insurance Service-Senior cohort. Incident AF was observed in 10 435 participants over an observational period of 1 629 903 person-years (0.64%/year). During the observational period, the incidence of dementia was 4.1 and 2.7 per 100 person-years in the incident AF and propensity score-matched AF-free groups, respectively. After adjustment, the risk of dementia was significantly increased by incident AF with a hazard ratio (HR) of 1.52 [95% confidence interval (CI) 1.43-1.63], even after censoring for stroke (1.27, 95% CI 1.18-1.37). Incident AF increased the risk of both Alzheimer (HR 1.31, 95% CI 1.20-1.43) and vascular dementia (HR 2.11, 95% CI 1.85-2.41). Among patients with incident AF, oral anticoagulant use was associated with a preventive effect on dementia development (HR 0.61, 95% CI 0.54-0.68), and an increasing CHA2DS2-VASc score was associated with a higher risk of dementia. CONCLUSION: Incident AF was associated with an increased risk of dementia, independent of clinical stroke in an elderly population. Oral anticoagulant use was linked with a decreased incidence of dementia.

Effect of hypertension duration and blood pressure level on ischaemic stroke risk in atrial fibrillation: nationwide data covering the entire Korean population.

AIMS: There are a paucity of data on the association of duration of hypertension and blood pressure (BP) level with risk of ischaemic stroke in patients with atrial fibrillation (AF). Our objective was to investigate the association between duration of hypertension and secondly, BP levels with risk of ischaemic stroke among patients with AF. METHODS AND RESULTS: A total of 246 459 oral anticoagulant-naïve non-valvular AF patients were enrolled from Korea National Health Insurance Service (NHIS) database (2005-2015). The risk of ischaemic stroke according to the duration of hypertension and systolic BP (SBP) levels were assessed. One-year increase of hypertension duration continuously increased the adjusted risk of ischaemic stroke (95% confidence interval 1.07-1.09) until 7 years, and reached a plateau with adjusted hazard ratio of 1.6. Risk of ischaemic stroke increased linearly with the increase of hypertension duration in patients younger than 65 years of age, whereas the risk reached a plateau in patients aged 65 years or older. In all baseline and pre-AF average SBP subgroups, longer duration of hypertension before AF was associated with higher ischaemic stroke risk than shorter duration of hypertension (all P-values for trends <0.01). However, the effect of long-term hypertension was not observed in patients with strictly well-controlled pre-AF average SBP of less than 120 mmHg. CONCLUSION: The increase of hypertension duration was associated with the increased risk of ischaemic stroke. However, this long-term effect of hypertension duration can be attenuated by long-term strict SBP control throughout the entire duration of hypertension.

Prevalence and Associated Stroke Risk of Human Immunodeficiency Virus-Infected Patients With Atrial Fibrillation　- A Nationwide Cohort Study.

BACKGROUND: Patients infected with human immunodeficiency virus (HIV) are at increased risk of cardiovascular diseases. However, little is known regarding the risk of ischemic stroke in HIV-infected individuals with atrial fibrillation (AF).Methods and Results:From the Korean National Health Insurance Service (NHIS) database from January 1, 2005 to December 31, 2016, we analyzed 962,116 patients with prevalent non-valvular AF aged ≥18 years. The overall HIV prevalence in AF patients was 0.17% (1,678 of 962,116). Oral anticoagulant (OAC)-naïve non-valvular AF (NVAF) patients with HIV had increased risks of ischemic stroke/systemic embolism (SE) [adjusted hazard ratio (HR) 1.37; 95% confidence interval (CI), 1.21-1.54], and major bleeding (adjusted HR 1.29; 95% CI, 1.15-1.46), compared with those without HIV. The incidence of ischemic stroke/SE in NVAF patients with HIV without any risk factors was similar to that of those without HIV at intermediate risk (i.e., male CHA2DS2-VASc score of 1) (2.04 vs. 2.18 events per 100 person-years). However, the use of OACs in AF patients with HIV was suboptimal, being only 8.9% at the time of AF diagnosis and 31.8% throughout the study period. CONCLUSIONS: The risks of ischemic stroke/SE and major bleeding were significantly higher in HIV-infected patients compared with non-HIV-infected patients with AF. Despite this, the actual use of OACs among AF patients with HIV was suboptimal.

Analysis of the Association Between MicroRNA Biogenesis Gene Polymorphisms and Venous Thromboembolism in Koreans.

Venous thromboembolism (VTE) involves the formation of a blood clot, typically in the deep veins of the leg or arm (deep vein thrombosis), which then travels via the circulatory system and ultimately lodges in the lungs, resulting in pulmonary embolism. A number of microRNAs (miRNAs) are well-known regulators of thrombosis and thrombolysis, and mutations in miRNA biogenesis genes, such as DICER1, DROSHA have been implicated in miRNA synthesis and function. We investigated the genetic association between polymorphisms in four miRNA biogenesis genes, DICER1 rs3742330A > G, DROSHA rs10719T > C, RAN rs14035C > T and XPO5 rs11077A > C, and VTE in 503 Koreans: 300 controls and 203 patients. Genotyping was assessed with polymerase chain reaction-restriction fragment length polymorphism assays. We detected associations between polymorphisms in RAN and XPO5 and VTE prevalence (RAN rs14035CC + CT versus TT: p = 0.018; XPO5 rs11077AA + AC versus CC: p < 0.001). Analysis of allele combinations of all four polymorphisms (DICER1, DROSHA, RAN, XPO5) revealed that A-T-T-A was associated with decreased VTE prevalence (p = 0.0002), and A-T-C-C was associated with increased VTE prevalence (p = 0.027). Moreover, in subjects with provoked VTE, the DROSHA rs10719T > C, polymorphism was associated with increased disease prevalence (TT versus TC + CC: p < 0.039). Our study demonstrates that RAN and XPO5 polymorphisms are associated with risk for VTE in Korean subjects.

Relationship Between Anemia and the Risk of Sudden Cardiac Arrest　- A Nationwide Cohort Study in South Korea.

BACKGROUND: The relationship between anemia and sudden cardiac arrest (SCA) is unclear in the general population, so we assessed it in a nationwide cohort.Methods and Results: We studied 494,948 subjects (mean age, 47.8 years; 245,333 men [49.6%]) with national health check-up data from the Korean National Health Insurance Database Cohort. During a mean follow-up period of 5.4 years, SCA occurred in 616 participants (396 men, 220 women). The incidence rates of SCA increased across the 4 anemia groups in both men (0.3, 1.5, 5.3, and 4.5 per 1,000 person-years) and women (0.2, 0.5, 0.5, and 1.2 per 1,000 person-years). The SCA risk per 1-unit decrease in hemoglobin (Hb) increased by 21% and 24%, respectively, in multivariable models adjusted for cardiovascular factors, in men (95% confidence interval [CI], 13-29%; P<0.001) and women (95% CI, 13-37%; P<0.001). A negative correlation between QTc interval and Hb level was observed in men, and a trend was observed in women. CONCLUSIONS: Anemia was associated with an increased risk of SCA even after accounting for concomitant conditions in a South Korean nationwide cohort. The correlation between anemia and SCA might be explained by an increase in arrhythmic risks, such as QTc prolongation.