P4776Age-dependent anti-thrombotic therapy for atrial fibrillation patients with intermediate risk (CHA2DS2-VASc Score of 1 or 2) of ischemic stroke

Background

Although older age is one of the most important risk factor for stroke in atrial fibrillation (AF), it is unclear whether oral anticoagulants are beneficial for AF patients with intermediate CHA2DS2-VASc score (1 for male or 2 for female) according to age threshold. We sought to investigate the effect of age-dependent antithrombotic therapy for ischemic stroke in Korean intermediate risk AF patients.

Methods

We enrolled 29,592 patients (males with CHA2DS2-VASc score of 1 and females with CHA2DS2-VASc score of 2) using the Korean National Health Insurance Service database. The clinical endpoint was the occurrence of ischemic stroke. The propensity score matching method was used to balance covariates across treated and untreated patients.

Results

Treated male AF patients were 6,570 (67.1%) with age <55 years, 7,115 (70.9%) with 55–64 years and 6,470 (68.3%) with 65–74 years in each age risk criterion. Also, treated female AF patients were 3,156 (71.3%) with age <55 years, 2,838 (71.0%) with 55–64 years and 3,440 (72.6%) with 65–74 years in each age risk criterion. Among male and female patients (age <55 years and 55–64 years) with 1 risk factor, an annual ischemic stroke rate was not significantly different between treated and untreated patients at full follow-up. However, treated AF patients who are in age 65–74 year without other risk factor had a much lower annual risk of ischemic stroke [(1.05%/year (male) and 1.04%/year (female)] compared with untreated patients [(1.77%/year (male) (p<0.026) and 1.86%/year (female) (p<0.041).

Conclusions

Age is an important predictor in determining the risk of ischemic stroke in AF patients with intermediate CHA2DS2-VASc scores (1 for male or 2 for female). We suggest that the benefit of anti-thrombotic therapy for intermediate risk AF patients depends on age threshold.

P5661Validation of CHA2DS2-VA score (excluding female sex) in non-valvular atrial fibrillation patients: a nationwide population-based study

Background

Sex category (Sc, ie, female sex) confers 1 point on CHA2DS2-VASc score. So, no woman with atrial fibrillation (AF) can have a CHA2DS2-VASc score of 0. This study aimed to compare CHA2DS2-VA (excluding female sex) and CHA2DS2-VASc score in Korean AF patients.

Methods

Using the Korean National Health Insurance Service database, we analyzed the risk of ischemic stroke in non-valvular AF patients between 2013 and 2017. The predictive value of the CHA2DS2-VA and CHA2DS2-VASc scores for ischemic stroke was evaluated by c-statistic difference and net reclassification improvement (NRI). The propensity score matching method was used to balance covariates across male and female AF patients.

Results

A total of 182,133 patients with AF (49.2% women) were included to this study. The adjusted incidence rate (IR) of ischemic stroke was not significantly different between males and females (0.89%/y and 0.90%/y, respectively, p=0.411) in low-risk patients without risk factor. Also, no sex difference was found in high-risk patients with above 2 risk factors for ischemic stroke (4.46%/y for male and 4.49%/y for male, p=0.498). In c-statistic analysis for ischemic stroke, there was no significant difference between the CHA2DS2-VA and CHA2DS2-VASc scores (AUC 0.662 vs. 0.664, z=1.572, p=0.116). When compared with CHA2DS2-VASc score, CHA2DS2-VA score was not significantly inferior in net reclassification improvement (NRI 0.031, 95% CI 0.002–0.037, p=0.118) for ischemic stroke.

C-statistics

Conclusions

In Korean AF patients, the CHA2DS2-VA score excluding female sex is a useful risk scoring system for ischemic stroke.

P6435A diagnostic prediction model of coronary artery disease in patient with chest pain using machine learning

Background

Chest pain is a major symptom of coronary artery disease (CAD), which can lead to acute coronary syndrome and sudden cardiac death. Accurate diagnosis of CAD in patients who experience chest pain is crucial to provide appropriate treatment and optimize clinical outcomes.

Objective

This study was to develop a machine learning model which can predict and diagnose CAD in patients complaining of chest pain based on a large real-world prospective registry database and computing power.

Method

A total of 10,177 subjects with typical or atypical chest pain who underwent a coronary angiography at the cardiovascular center of our University Hospital, South Korea between November 2004 and May 2014 were evaluated in this study. The generation of the diagnostic prediction model for CAD used the classification application by technical support of MATLAB R2017a. The performance evaluation of the learning model generated by machine learning was evaluated by the area under the curve (AUC) of the receiver-operating characteristic (ROC) analysis.

Results

The diagnostic prediction model of CAD had been generated according to the user's accessibility such as the general public or clinician (Model 1–4). The performance of the models has ranged from 0.78 to 0.96 by the AUC of ROC analysis. The prediction accuracy of the models ranged from 70.4% to 88.9%. The performance of the diagnostic prediction model of CAD by machine learning improved as the input information increased.

Figure 1. Study Flow Chart

Conclusion

A diagnostic prediction model of CAD using the machine learning method and the registry database was developed. Further studies are needed to verify our results.

6112Usefulness of the trans-stent fractional flow reserve gradient for predicting clinical outcomes

Aims

The clinical meaning of a trans-stent pressure gradient after DES implantation has not been estimated adequately. We evaluated the usefulness of a fractional flow reserve (FFR) gradient across the stent (ΔFFRstent) for long-term clinical outcomes after percutaneous coronary intervention (PCI) with a drug-eluting stent (DES).

Methods and results

FFR pull-back and intravascular ultrasound (IVUS) were performed after successful PCI in 135 left anterior descending artery lesions. ΔFFRstent was defined as the FFR gradient across the stent. The ΔFFRstent/length was defined as the ΔFFRstent value divided by the total stent length multiplied by 10 [= (ΔFFRstent ÷ stent length) x 10]. Major adverse cardiac events (MACEs) were the composite of all-cause death, target vessel related myocardial infarction, and target lesion revascularisation. Despite successful PCI without significant complications on IVUS, ΔFFRstent >0 was observed in 98.5% of cases. ΔFFRstent ≥0.04 and ΔFFRstent/length ≥0.009 predicted suboptimal stenting defined as final minimal stent area <5.5 mm2. During 2183±898 days, the MACE-free survival rate was significantly lower in patients with ΔFFRstent ≥0.04 and ΔFFRstent/length ≥0.009 compared to those with lower values (69.6 vs. 93.4%, log-rank p=0.031; 72.1 vs. 97.7%, log-rank p=0.003, respectively). ΔFFRstent/length ≥0.009 (hazard ratio 10.1, p=0.032) was an independent predictor of MACE.

Trans-stent FFR and MACE

Conclusion

A trans-stent FFR gradient was frequently observed in DES-treated patients despite successful PCI results. ΔFFRstent and ΔFFRstent/length are useful indicators for optimising a DES and are related to long-term outcomes.

P1944Relationship between the duration of hypertension and cerebral and cardiovascular disease in the adult Korean population

Background

Although advances in medical technology and health care have led to increased life expectancy, the prevalence of chronic diseases such as hypertension, diabetes, stroke and cardiovascular events has increased.

Purpose

This study evaluated the prevalence of hypertension, treatment, and the impact of hypertension on cardiovascular disease (CVD) and stroke risk in Koreans.

Methods

The Korean National Health and Nutritional Examination Survey (KNHANES) database, which is a stratified random sampling to assess the health and nutritional status of Koreans (https://knhanes.cdc.go.kr), was analyzed for this study. The subjects of the survey were sampled to represent the entire population of the Republic of Korea. The endpoints of the study are the risk of CVD and stroke due to the prevalence of hypertension. We also examined the relationship between the control of hypertension and the risk of CVD and stroke.

Results

The prevalence of hypertension has increased rapidly as with longer life expectancy of the population. As the duration of hypertension increases, CVD and stroke risks are increased. Achieving a target goal blood pressure below 140/90 mmHg can reduce the risk of all CVD and stroke by nearly half.

Korea-HTN

Conclusion

The risk of CVD and stroke in hypertensive patients can be significantly reduced by achieving optimal blood pressure control.

Genotype and Phenotype Spectrum of FRMD7-Associated Infantile Nystagmus Syndrome

Purpose

We investigate the genotype and phenotype spectrum of FRMD7-associated infantile nystagmus syndrome in Korean probands.

Methods

A total of 37 patients with infantile nystagmus syndrome were recruited prospectively for genetic analysis. We performed polymerase chain reaction (PCR)-based direct sequencing and haplotype analysis for FRMD7. Detailed ophthalmic examinations and eye movement recordings were compared between FRMD7 and non-FRMD7 groups.

Results

In 13 (35%) of 37 patients, five different mutations of FRMD7 were detected: start codon mutation c.1A>G, splice site mutation c.162+6T>C, and three missense mutations (c.575A>C, c.722A>G, and c.875T>C). The latter mutation was identified in seven unrelated patients, and always was accompanied with two single nucleotide polymorphisms of exon 12 (rs6637934, rs5977623). Compared to non-FRMD7 groups, a cup-to-disc ratio was significantly decreased in FRMD7 groups (P < 0.001), and a disc-macula distance to disc diameter ratio markedly increased in the FRMD7 group (P = 0.015). Most patients in the FRMD7 group had at least two types of the nystagmus waveforms, and the most common type was unidirectional jerk nystagmus (75%), such as pure jerk and jerk with extended foveation, followed by pendular (25%), bidirectional jerk (19%), and dual jerk (6%) nystagmus. No significant differences were observed between FRMD7 and non-FRMD7 groups in terms of the nystagmus waveform, presence of periodic alternating nystagmus, and mean foveation time.

Conclusions

We identified five FRMD7 mutations in 35% of our infantile nystagmus syndrome cohort, expanding its mutational spectrum. The missense mutation c.875T>C may be a common mutation arisen from the founder effect in Korea. Optic nerve dysplasia associated with FRMD7 mutations suggests that the abnormal development of afferent visual systems may affect neural circuitry within the oculomotor system.

Correction to: Characteristics of single ocular motor nerve palsy associated with anti-GQ1b antibody

The original version of this article unfortunately contained a mistake.

Acquired Ocular Motor Nerve Palsy in Neurology Clinics: A Prospective Multicenter Study

BACKGROUND AND PURPOSE

This study aimed to determine the patterns and etiologies of acquired ocular motor nerve palsy (OMNP) diagnosed in neurology clinics. We also investigated the clinical features that may predict the causes other than microvascular ischemia in isolated OMNP.

METHODS

We performed a prospective multicenter study that had recruited 298 patients with acquired OMNP from the neurology clinics of referral-based 9 university hospitals in Korea. We finally selected 235 patients with isolated OMNP and divided them into older (age ≥50 years, n=188) and younger (age <50 years, n=47) groups. We investigated the underlying etiologies of acquired OMNP. We also estimated the frequency of microvascular ischemia and other causes in isolated OMNP, and sought to determine the clinical features that can predict the causes other than microvascular ischemia.

RESULTS

Abducens nerve palsy was the most common (40%) of the acquired OMNPs, followed by oculomotor nerve palsy (27%), trochlear nerve palsy (23%), and multiple OMNPs (10%). The etiologies included microvascular ischemia (47%), inflammatory (21%), stroke (5%), trauma (5%), neoplasm (3%), and others (2%), with the cause not being determined in 13% of the patients. Microvascular ischemia was the most common cause (83%) in patients aged ≥50 years with isolated OMNP, followed by inflammation (6%), stroke (6%), neoplasm (3%), and aneurysm (1%). Microvascular ischemia was more common in the older than the younger group (83% vs. 49%, p<0.001). The intensity of headache was the only risk factor for causes other than microvascular ischemia in isolated OMNP.

CONCLUSIONS

Vascular and inflammatory disorders are the most common causes of acquired OMNP diagnosed in neurology clinics. Microvascular ischemia was the predominant cause of isolated OMNP. Severe headache indicates causes other than microvascular ischemia in isolated OMNP.

Characteristics of single ocular motor nerve palsy associated with anti-GQ1b antibody

To define the prevalence and characteristics of single ocular motor nerve palsy (OMNP) associated with positive serum anti-GQ1b antibody. We performed a prospective multicenter study that recruited 82 patients with single OMNP without identifiable causes from the history and neuroimaging in six neurology clinics of university hospitals. We measured serum anti-GQ1b antibody in all participants. Twelve patients with multiple OMNP and 30 with identifiable causes served as the controls. Overall, the prevalence of anti-GQ1b antibody syndrome was 10% (8/82) in patients with single OMNP and 6% (5/78) in those with single OMNP in isolation. None of the 14 patients with OMNP with identifiable causes showed positive serum anti-GQ1b antibody. The prevalence of anti-GQ1b antibody syndrome was much higher in patients with multiple OMNP than in those with single OMNP (50% vs. 10%, p < 0.01). Patients with single OMNP and positive anti-GQ1b antibody are younger (42 ± 16 vs. 58 ± 15, p < 0.05) and had a significantly higher frequency of preceding infection (75 vs. 19%, p < 0.05) and other neurological signs (38 vs. 1%, p < 0.05) than those with negative antibody. Eight patients with single OMNP and positive serum anti-GQ1b antibody involved the abducens (n = 6), trochlear (n = 1), or oculomotor nerve (n = 1). Single OMNP accompanying other neurological signs and multiple OMNP are more likely to be associated with anti-GQ1b antibody. Anti-GQ1b antibody syndrome should be considered even in patients with single OMNP, especially when antecedent infection was associated in younger patients.

Identification of a novel GPR143 mutation in X-linked ocular albinism with marked intrafamilial phenotypic variability

Ocular albinism type 1 (OA1) is an X-linked inherited disease characterized by impaired visual acuity, congenital nystagmus, foveal hypoplasia, hypopigmentation of iris and fundus. It is caused by mutations in the G protein-coupled receptor143 (GPR143) gene. The genetic characteristics of OA1 have not been well defined in Asians. In this study, six members from three consecutive generations of a Korean family with OA1 were enrolled. We performed whole-exome sequencing followed by validation and segregation analysis. Two affected patients underwent detailed ophthalmic examinations and eye movement recordings. Of the two affected males, the proband had all classical phenotypes of OA1, but the other showed isolated foveal hypoplasia without nystagmus. We identified a hemizygous missense (c.623C > A, p.Ala208Glu) mutation of GPR143 in affected males. This mutation was also present as heterozygous in two obligate female carriers, and was not found in unaffected members. Our data expands thespectrum of phenotypes and genotype in GPR143 in Asians, and highlights the phenotypic heterogeneity in OA1.

Early MRI-negative posterior circulation stroke presenting as acute dizziness

The aim of this study was to determine the frequency, clinical and radiological features, and efficacy of clinical evaluation and perfusion-weighted imaging (PWI) for the prediction of final stroke in patients with DWI/MRI-negative posterior circulation stroke (PCS) presenting acute dizziness/vertigo. From our comprehensive prospective stroke registry of acute ischemic stroke during a 7-year period, we identified 1846 consecutive patients with PCS, 850 of whom presented with acute dizziness/vertigo. Of these 850 patients, initial DWI-MRI was negative in 35 (4.1%). In these 35 patients, dizziness/vertigo was acute prolonged in 31 and recurrent transient in 4. Focal neurological signs or profound imbalance were present in 16/35 or 18/34, respectively. Spontaneous nystagmus was absent in 21/35; the HINTS protocol (head impulse, nystagmus, and test-of-skew) was not applicable to them. In 12/26 patients, PWI was positive and the same time as DWI was negative. The usual site of lesion was the lateral medulla (n = 18). Twenty-nine patients (83%) had small strokes, while 19 (54%) had large vessel strokes. The sensitivity of systematic clinical evaluation adopting neurological examination, HINTS plus, and assessment of equilibrium was 83%, for prediction of final stroke and 100% when combined with PWI. An integrated approach using systematic neurological and neuro-otological examinations combined with PWI accurately diagnoses PCS presenting with acute dizziness/vertigo. Although most patients with acute vertigo and MRI-negative PCS have small brainstem strokes, about a half have large vessel stroke with greater risk of progression requiring prompt treatment.

Persistent geotropic positional nystagmus in unilateral cerebellar lesions

Objective

To determine the prevalence of central lesions in persistent geotropic positional nystagmus, and characteristics and anatomical substrates of the nystagmus in cerebellar lesions.

Methods

We prospectively recruited 58 patients with persistent geotropic positional nystagmus at the Dizziness Clinic of Pusan National University Hospital. Seven patients with unilateral cerebellar lesions were subjected to analysis of clinical characteristics, oculographic data, and MRI lesions. For comparison, we studied 37 cases of peripheral persistent geotropic positional nystagmus.

Results

The prevalence of central lesions in persistent geotropic positional nystagmus was 12% (7/58). Persistent geotropic positional nystagmus in cerebellar lesions was mostly asymmetrical. Horizontal nystagmus changed in direction during the bow-and-lean test with null positions. All patients showed impaired horizontal smooth pursuit bilaterally, and 3 of them also had positional downbeat nystagmus. The peak intensity and asymmetry of persistent geotropic positional nystagmus did not differ between central and peripheral groups (p > 0.05), while there was a difference in the maxima. Lesion overlays revealed that damage to the cerebellar tonsil was responsible for the generation of persistent geotropic positional nystagmus.

Conclusion

Although persistent geotropic positional nystagmus in cerebellar lesions shares the characteristics of nystagmus measures with peripheral cases, accompanying central oculomotor signs can aid in differentiation. In tonsillar lesions, compensatory rotational feedback due to erroneous estimation of the direction of gravity may generate constant horizontal geotropic positional nystagmus.

Low rates of osteoporosis treatment after hospitalization for hip fracture in Hawaii

We evaluated osteoporosis treatment and DEXA utilization rates of patients who were admitted for hip fracture in a single healthcare system in Hawaii from 2015 to 2016. We found that osteoporosis treatment and DEXA utilization rates were low, highlighting a critical gap in osteoporosis care after admission for hip fracture.

INTRODUCTION

The objective of this study was to evaluate osteoporosis care after an admission for hip fracture at three community hospitals within a single healthcare system in Hawaii.

METHODS

A retrospective chart review was conducted (n = 428) of patients ≥ 50 years and hospitalized for hip fractures between January 1, 2015, and May 31, 2016, at three major hospitals within Hawaii Pacific Health, a large healthcare system in Hawaii. Basic demographics were collected, and medications prescribed were quantified and described within 1 year of hip fracture. Logistic regression was used to evaluate the association between collected variables and the odds of osteoporosis treatment.

RESULTS

Only 115 (26.9%) patients were prescribed a medication for osteoporosis as a secondary prevention within a year of hospitalization for hip fracture. DEXA scans were performed in 137 (32.0%) patients. Most of the treated patients were prescribed oral bisphosphonates. Treatment facility, female gender, and higher BMI were found to be predictive factors for osteoporosis treatment.

CONCLUSION

The use of osteoporosis medication for secondary prevention after admission for hip fracture in Hawaii is low. Efforts need to be made to improve treatment rates, especially among males.