Outbursts from an ice-marginal lake in Antarctica in 1969-1971 and 2017, revealed by aerial photographs and satellite data

The liquid water around the Antarctic Ice Sheet plays a key role in modulating both the vulnerability of ice shelves to hydrofracturing and ice discharge from outlet glaciers. Therefore, it needs to be adequately constrained for precise future projections of ice-mass loss and global sea-level rise. Although glacial lake outburst floods (GLOFs) pose one of the greatest risks in glacierized mountainous regions, any long-term monitoring of Antarctic ice-marginal lakes and their associated potential for GLOFs has been neglected until recently owing to the limited number of such events reported in Antarctica. Here we present direct evidence of repeated GLOFs from Lake Kaminotani-Ike, an ice-sheet-dammed lake in East Antarctica, via an analysis of historical aerial photographs and recent satellite data. Two GLOFs occurred in 1969-1971 and 2017, with discharge volumes of (8.6 ± 1.5) × 107 and (7.1 ± 0.4) × 107 m3, respectively, making them two of the largest GLOFs in Antarctica. A southerly oceanward pathway beneath the ice sheet is the most likely drainage route of these GLOF events based on the available surface- and bed-elevation datasets. Furthermore, the 2017 event occurred during the austral winter, thereby implying the possibility of year-round active subglacial networks in Antarctica. Our results highlight that studies on Antarctic ice-marginal lakes provide an opportunity to better understand Antarctic hydrological processes and emphasize the need for both detailed monitoring of ice-marginal lakes and detailed surveying of the subglacial environments of the Antarctic Ice Sheet.

Association of beta blocker use with new-onset heart failure and mortality in atrial fibrillation without pre-existing heart failure: the Fushimi AF registry

Background

Heart failure (HF) is one of the major complications in atrial fibrillation (AF). We previously reported that not a few AF patients without pre-existing HF (defined as prior HF hospitalization, New York Heart Association functional class≥2, or left ventricular ejection fraction (LVEF)<40%) subsequently developed new-onset HF. Beta blockers are the established therapy for HF, but it remains unclear whether beta blockers prevent new-onset HF and improve outcomes in AF patients without preexisting HF.

Methods

In the Fushimi AF registry, 778 of 3,262 patients without pre-existing HF were receiving beta blockers at baseline. We investigated the incidence of new-onset HF defined as cardiac death or HF hospitalization, and all-cause death in a propensity-matched cohort (N=1,198; mean age, 71 years; 39% female; mean LVEF, 66%). Additionally, annual follow-up prescription data before the onset of events were collected in 294 of patients with beta blockers and 395 of those without beta blockers. We also investigated the association of starting or stopping beta blockers with the incidence of new-onset HF and all-cause death.

Results

During the median follow-up of 5.8 years, new-onset HF and all-cause death occurred in 77 (12.9%) and 118 (19.7%) of patients with beta blockers, and 70 (11.7%) and 131 (21.9%) of those without beta blockers, respectively. Incidence of new-onset HF was comparable between patients with and without beta blockers (Figure 1), and incidence of all-cause death was also comparable between the two groups (Figure 2). In exploratory subgroup analyses, there was no interaction in the association of beta blockers with the incidence of events, except for pulse rate for new-onset HF and left atrial size for all-cause death. Hazard ratio of beta blockers for new-onset HF tended to be lower in patients with higher pulse rates (>84 bpm) (Figure 1), and that for all-cause death was lower in those without left atrial enlargement (Figure 2). Of patients with follow-up prescription data, beta blockers were stopped in 55 (18.7%) and started in 97 (24.6%) patients, respectively. Patients with starting beta blockers had higher pulse rate (78.5±17.3 vs 74.9±13.9 bpm; p=0.03) and more symptomatic AF (58.8% vs 46.0%; p=0.03) compared to those without starting beta blockers, while there was no difference in baseline characteristics between those with and without stopping beta blockers. During the follow-up, the incidences of new-onset HF and all-cause death were also comparable between the patients with and without stopping beta blockers and those with and without starting beta blockers.

Conclusion

Beta blockers were not associated with the incidence of new-onset HF and all-cause death in AF patients without pre-existing HF. However, the exploratory subgroup analyses suggested the existence of subjects who may benefit from beta blockers.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Boehringer Ingelheim, Bayer Healthcare, Pfizer, Bristol-Myers Squibb, Astellas Pharma, AstraZeneca, Daiichi Sankyo, Novartis Pharma, MSD, Sanofi-Aventis, and Takeda Pharmaceutical.

Clinical characteristics and outcomes of atrial fibrillation patients with peripheral artery disease: the Fushimi AF Registry

Background

Atrial fibrillation (AF) represents the common arrhythmia and increases the risk of thromboembolism. Risk assessment for thromboembolism is important for the management of AF patients. Peripheral artery disease (PAD) is identified as a risk factor for thromboembolism in CHA2DS2-VASc score. However, there are little data on clinical characteristics and cardiovascular events of AF patients with PAD.

Purpose

In this study, we investigated the clinical characteristics and outcomes of AF patients with PAD.

Methods

The Fushimi AF Registry, a community-based prospective survey, was designed to enroll all of the AF patients who visited the participating medical institutions in Fushimi-ku, Kyoto, Japan. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011 and follow up data including prescription status were available in 4,464 patients from March 2011 to August 2021. Median follow-up period was 1,848 days.

Results

Of 4,464 patients, 183 patients had PAD (4.1%; PAD group). The mean age was higher in PAD group than no-PAD group (PAD group vs. no-PAD group: 76.7 vs. 73.5; p<0.01). Patients with PAD had more co-morbidities such as stroke, systemic embolism, congestive heart failure, hypertension, diabetes mellitus, dyslipidemia coronary artery disease and chronic kidney disease than those without PAD. Thus, CHADS2 score, CHA2DS2-VASc score and HAS-BLED score were higher in PAD group than no-PAD group (2.81 vs. 2.00; p<0.01, 5.17 vs. 3.30; p<0.01, 2.42 vs. 1.71; p<0.01, respectively). The proportion of patients with oral anticoagulant was similar between the two groups and the proportion of patients with antiplatelet drug was higher in PAD group than no-PAD group (59.0% vs. 55.6%; p=0.36, 62.9% vs. 24.7%; p<0.01, respectively). The incidences of all-cause death, cardiac death and myocardial infarction were higher in PAD group than no-PAD group (11.4 vs. 4.6 per 100 person-years; log-rank p<0.01, 1.7 vs. 0.8 per 100 person-years; log-rank p<0.01, 1.2 vs. 0.2 per 100 person-years; log-rank p<0.01). However, the incidence of stroke or systemic embolism was similar between the two groups (2.9 vs. 2.2 per 100 person-years, log-rank p=0.19). Finally, the incidence of composite of cardiac death, stroke, systemic embolism or myocardial infarction was higher in PAD group than no-PAD group (6.0 vs. 3.0 per 100 person-years; log-rank p<0.01).

Conclusion

AF patients with PAD had significantly higher risk for death and cardiac events, whereas the incidence of thromboembolism was similar between AF patients with and without PAD.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Japan Agency for Medical Research and Development

Association of cardiothoracic ratio with heart failure hospitalization in patients with atrial fibrillation: the Fushimi AF Registry

Background

Chest radiography is the most common diagnostic imaging test in clinical medicine, and the cardiothoracic ratio (CTR) is a readily available and non-invasive tool with which to assess the volume status and cardiomegaly. However, it remains unknown whether CTR on chest radiography is associated with the incidence of HF hospitalization in AF patients remains unclear.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Kyoto, Japan. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011, and follow-up data were available for 4,489 patients by the end of August 2021. In the present study, 3,727 patients with available data of CTR were examined. We divided the patients into two groups according to their CTR at baseline; Higher group (CTR ≥50.0%, n=2,696) and Lower group (CTR <50.0%, n=1,031), and compared the clinical background and outcomes between the two groups.

Results

The proportion of female was grater in Higher group, and the patients in Higher group were older. The patients in Higher group had higher prevalence of HF, hypertension and chronic kidney disease. During the median follow-up of 3,033 days, in Kaplan-Meier analysis, the incidence rates of HF hospitalization were higher in Higher group (Higher group: 2.5% per person-year vs. Lower group: 1.1%; p<0.01). Multivariate Cox proportional hazards regression analysis revealed that higher CTR (≥50.0%) was an independent determinant of the incidence of HF hospitalization. Furthermore, when we divided the patients into four groups based on the quartile of CTR; Q1 (CTR<49.0%), Q2 (49.0≤CTR<53.8%), Q3 (53.8≤CTR<59.0%), Q4 (59.0%≤CTR), the incidence of HF hospitalization was more frequent in patients with higher CTR, regardless of the presence or absence of prior hospitalization for HF (Figure).

Conclusion

In Japanese AF patients, patients with higher CTR had significantly higher incidence of HF hospitalization, regardless of the prevalence of prior hospitalization for HF.

Funding Acknowledgement

Type of funding sources: None.

The association of left ventricular ejection fraction with incident heart failure in patients with atrial fibrillation

Background

Atrial fibrillation (AF) increases the risk of incident heart failure (HF). Left ventricular ejection fraction (LVEF) is an important prognostic parameter in patients with HF. However, little is known regarding the association of LVEF with incident HF in patients with AF.

Purpose

The aim of this study is to investigate the relationship between LVEF at enrollment and incidence of HF hospitalization during follow-up period in patients with AF.

Methods

The Fushimi AF Registry is a community-based prospective survey of patients with AF in Fushimi-ku, Kyoto, Japan. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011, and follow-up data were available for 4,489 patients by the end of August 2021. In the present study, we investigated 3,544 patients with the data of LVEF at enrollment. We divided the patients into 4 groups stratified by LVEF (reduced LVEF [LVEF <40%], mildly reduced LVEF [LVEF: 40–49%], slightly reduced LVEF [LVEF: 50–59%], and normal LVEF [LVEF ≥60%]), and compared the backgrounds and outcomes between these 4 groups.

Results

Of 3,544 patients, the mean age was 73.6±10.7 years, 1,420 (40%) were female, 1,781 (50%) were paroxysmal AF, and 1,085 (30%) had pre-existing HF. The mean CHADS2 and CHA2DS2-VASc scores were 2.1±1.3 and 3.4±1.7, respectively. The mean LVEF at enrollment was 63±12% (reduced LVEF: 197 [6%], mildly reduced LVEF: 250 [7%], slightly reduced LVEF: 532 [15%] and normal LVEF: 2,565 [72%], respectively). Patients with lower LVEF demonstrated lower prevalence of female and paroxysmal AF, and had a higher CHADS2 and CHA2DS2-VASc scores (all P<0.01). A total of 605 patients were hospitalized for HF during the median follow-up period of 5.5 years, corresponding to an annual incidence of 3.4% per person-year. Kaplan-Meier curves demonstrated that LVEF at enrollment could stratify the incidence of HF hospitalization during follow-up in patients with AF (Picture 1). Multivariable Cox regression analysis revealed that lower LVEF strata were significantly associated with the increased risk of HF hospitalization even after adjustment by age, sex, type of AF and CHA2DS2-VASc score (Picture 1). An increased risk of HF hospitalization was observed even in patients with mildly reduced LVEF (adjusted hazard ratio: 2.56, 95% CI: 1.99–3.29) as well as in those with slightly reduced LVEF (adjusted hazard ratio: 1.79, 95% CI: 1.45–2.22) compared with those with normal LVEF. These results were also the case in AF patients without pre-existing HF (Picture 2).

Conclusion

LVEF at enrollment could stratify the incidence of HF hospitalization in patients with AF, suggesting the importance of measuring LVEF in all patients with AF. Even mildly (LVEF: 40–49%) or slightly (LVEF: 50–59%) reduced LVEF was independently associated with the risk of incident HF in patients with AF.

Funding Acknowledgement

Type of funding sources: None.

Characteristics of speech perception by distantly-presented bone-conducted ultrasound assessed by word intelligibility and monosyllable articulation tests

High-frequency sounds above 20 kHz presented via bone conduction can be heard clearly and transmit speech information using amplitude modulation. Additionally, bone-conducted ultrasound (BCU) can be perceived even when the vibrator is presented to body parts distant from the head, such as the neck, arm, and trunk. To evaluate this previously presented BCU hearing, word intelligibility and monosyllable articulation tests were conducted in Japanese. The results suggested that a practical speech transmission, comparable to ordinary BCUs presented onto the head, can be obtained by distantly presented BCU.

Extraction of GRACE/GRACE-FO observed mass change patterns across Antarctica via independent component analysis (ICA)

Here we qualitatively analyse the mass change patterns across Antarctica via independent component analysis (ICA), a statistics-based blind source separation method to extract signals from complex data sets, in an attempt to reduce uncertainties in the glacial isostatic adjustment (GIA) effects and improve understanding of Antarctic Ice Sheet (AIS) mass-balance. We extract the six leading independent components from gravimetric data acquired during the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) missions. The results reveal that the observed continental-scale mass changes can be effectively separated into several spatial patterns that may be dominated by different physical processes. Although the hidden independent physical processes cannot be completely isolated, some significant signals, such as glacier melt, snow accumulation, periodic climatic signals, and GIA effects, can be determined without introducing any external information. We also observe that the time period of the analysed data set has a direct impact on the ICA results, as the impacts of extreme events, such as the anomalously large snowfall events in the late 2000s, may cause dramatic spatial and temporal changes in the ICA results. ICA provides a unique and informative approach to obtain a better understanding of both AIS-scale mass changes and specific regional-scale spatiotemporal signal variations.

Association of low total cholesterol level with clinical outcomes in patients with atrial fibrillation: the Fushimi AF registry

Background

Hyperlipidemia is a well-established risk factor for cardiovascular disease. However, low cholesterol is also reported to be associated with poor outcome in patients with chronic disease, which is called “cholesterol paradox”, and the association of cholesterol level with the incidence of clinical outcomes in patients with atrial fibrillation (AF) remains unclear.

Methods

In the Fushimi AF Registry, a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto, Japan, follow-up data and baseline total cholesterol levels were available in 3,054 patients. We excluded 767 patients who were taking statins, and 2,267 patients were included in the analyses. We defined low cholesterol as total cholesterol <150 mg/dl, and examined the incidence of all-cause death, stroke/systemic embolism (SE), heart failure (HF) hospitalization, and major bleeding.

Results

Patients with low cholesterol (N=464 (20.4%)) were older, more often male, and had higher prevalence of low body weight (<50 kg), permanent/persistent AF, prior stroke/SE, HF, chronic kidney disease, and anemia (hemoglobin <11 g/dl). CHA2DS2-VASc score was higher in patients with low cholesterol (low cholesterol vs others; 3.6±1.6 vs 3.2±1.7: P<0.001). Prescription of oral anti-coagulants was comparable between the groups (50.0% vs 54.5%: P=0.09). During the median follow-up of 1,805 days, the incidence of all-cause death, stroke/SE, HF hospitalization, and major bleeding was significantly higher in patients with low cholesterol (all-cause death, 10.9 vs 3.8 /100 person-years; stroke/SE, 3.4 vs 1.9 /100 person-years; HF hospitalization, 4.7 vs 2.5 /100 person-years; major bleeding, 2.7 vs 1.4 /100 person-years) (Figure 1). After adjustment for the components of CHA2DS2-VASc score, low body weight, permanent/persistent AF, chronic kidney disease, anemia, and prescription of oral anti-coagulants, low cholesterol was significantly associated with the incidence of all-cause death and stroke/SE, but not with that of HF hospitalization or major bleeding (Figure 2, model 3). Total cholesterol levels were still significantly and inversely associated with the incidence of all-cause death (hazard ratio, 0.94; 95% confidence interval, 0.92–0.96 for 10 mg/dl increase) and stroke/SE (hazard ratio, 0.96; 95% confidence interval, 0.92–0.999 for 10 mg/dl increase), when analyzed as continuous variables. Subgroup analysis revealed that the risk of low cholesterol for all-cause death was more pronounced in female (interaction P, 0.049), patient without prior stroke/SE (interaction P, 0.01), those without HF (interaction P, 0.01), and those without vascular disease (interaction P, 0.001). The risk for stroke/SE was more pronounced in patients without vascular disease (interaction P, 0.01).

Conclusion

Low total cholesterol level was significantly associated with the incidence of all-cause and stroke/SE in AF patients not taking statins, suggesting the existence of cholesterol paradox in AF.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Boehringer Ingelheim, Bayer Healthcare, Pfizer, Bristol-Myers Squibb, Astellas Pharma, AstraZeneca, Daiichi-Sankyo, Novartis Pharma, MSD, Sanofi-Avent

The relationship between diastolic blood pressure and the risk of cardiovascular events in patients with atrial fibrillation whose systolic blood pressure was treated to less than 130 mmHg

Background

Hypertension is one of the major risk factors of cardiovascular events in patients with atrial fibrillation (AF). Low diastolic blood pressure (DBP) has been reported to be associated with the incidence of cardiovascular events, but current guidelines recommend an intensive blood pressure target of less than 130/80 mmHg for AF patients taking oral anticoagulants without mentioning the lower limits of DBP.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in a city of Japan. Follow-up data were available in 4,472 patients, and hypertensive patients who received prescription of any antihypertensive agents and whose systolic blood pressure was treated to less than 130 mmHg were available were examined (n=1,319). We divided the patients into four groups according to their DBP at baseline; G1 (DBP<60 mmHg, n=349), G2 (60≤DBP<70, n=434), G3 (70≤DBP<80, n=386) and G4 (80≤DBP, n=150), and compared the clinical background and outcomes among groups.

Results

The proportion of female was grater in G1 group, and the patients in G1 group were older. During the median follow-up of 2,458 days, in Kaplan-Meier analysis, the incidence rates of cardiovascular events (composite of cardiac death, ischemic stroke, systemic embolism, non-fatal myocardial infarction and heart failure hospitalization during follow up) were the highest in G1 group and the lowest in G3 group (G1: 7.2% per person-year vs. G2: 4.9% vs. G3: 2.2% vs. G4: 4.4%; p<0.01). Multivariate Cox proportional hazards regression analysis revealed that DBP was an independent determinant of cardiovascular events (G1 vs. G3; hazard ratio (HR): 1.96, 95% confidence intervals (CI): 1.39–2.76, G2 vs. G3; HR: 1.79, 95% CI: 1.28–2.50, G4 vs. G3; HR: 1.56, 95% CI: 0.99–2.45) (Figure 1). When we examined the association of DBP according to 10 mmHg increment, patients with excessively low DBP (<50 mmHg) had significantly higher incidence of cardiovascular events than patients with DBP of 70–79 mmHg (HR: 2.80, 95% CI: 1.81–4.33), and DBP exhibited J curve association with higher incidence of cardiovascular events (Figure 2).

Conclusion

In Japanese AF patients whose systolic blood pressure was treated to less than 130 mmHg, patients with excessively low DBP had significantly higher incidence of cardiovascular events, and DBP exhibited J curve association with higher incidence of cardiovascular events.

Funding Acknowledgement

Type of funding sources: None.

Previous pacemaker therapy was not associated with the risk of clinical events in patients with atrial fibrillation: the Fushimi AF Registry

Background

Patients with atrial fibrillation (AF) occasionally require pacemaker implantation. Meanwhile, patients with implanted pacemaker are occasionally found to have subclinical AF and develop clinical AF. However, little is known about the clinical outcomes of AF patients with implanted pacemaker.

Purpose

We aimed to investigate the clinical outcomes in AF patients undergoing previous pacemaker therapy.

Methods

The Fushimi AF Registry is a community-based prospective survey of the AF patients in a city of Japan. Follow-up data including prescription status were available for 4,447 patients. After exclusion of patients with implantable cardioverter defibrillator and cardiac resynchronization therapy, we investigated 293 AF patients with pacemaker implantation at baseline. We performed propensity score-matching analysis to assess the impact of pacemaker therapy in AF patients.

Results

Of a total cohort, patients with pacemaker were more often female (51.2% vs. 39.7%; p<0.01) and older (78.0 vs. 73.3 years of age; p<0.01). Patients with pacemaker were more likely to have pre-existing heart failure (33.1% vs. 26.6%; p<0.01), valvular heart disease (22.9% vs. 16.8%; p<0.01), chronic kidney disease (48.8% vs. 34.7%; p<0.01), and history of performing direct current cardioversion (7.2% vs. 3.1%; p<0.01), compared with patients without pacemaker. Mean CHA2DS2-VASc score was higher in patients with pacemaker (3.80 vs. 3.34; p<0.01). Patients with pacemaker were more often prescribed oral anticoagulants (62.1% vs. 55.2%; p=0.02), verapamil (13.3% vs. 9.4%; p=0.03), and loop diuretics (30.7% vs. 21.8%; p<0.01). Using propensity score-matching, 291 patients with pacemaker and 291 without pacemaker were matched and baseline characteristics were comparable. The median follow-up period was 1,819 days. All-cause death occurred in 91 patients with pacemaker (6.0 /100 person-years) and 79 patients without pacemaker (5.9 /100 person-years), with a hazard ratio (HR) for patients with pacemaker of 1.01 (95% confidence interval [CI], 0.75 to 1.37; p=0.93). Furthermore, HR of cardiac death for patients with pacemaker was 1.00 (95% CI, 0.23 to 4.32; p=0.99), that of stroke or systemic embolism was 0.69 (95% CI, 0.44 to 1.07; p=0.10) and that of hospitalization for heart failure was 0.94 (95% CI, 0.65 to 1.37; p=0.76).

Conclusion

We identified that patients undergoing previous pacemaker therapy were not associated with the incidence of various adverse clinical events in Japanese AF patients.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Boehringer Ingelheim, Bayer Healthcare, Pfizer, Bristol-Myers Squibb, Astellas Pharma, AstraZeneca, Daiichi Sankyo, Novartis Pharma, MSD, Sanofi-Aventis, Takeda Pharmaceutical, and the Practical Research Project for Life-Style related Diseases including Cardiovascular Diseases and Diabetes Mellitus from Japan Agency for Medical Research and Development.

Association of the degree of thrombocytopenia with cause of death in patients with atrial fibrillation: the Fushimi AF Registry

Background

Thrombocytopenia is sometimes found in routine blood tests and is associated with an increased risk of mortality in general population. We have previously reported that atrial fibrillation (AF) patients with thrombocytopenia have a higher mortality than those without thrombocytopenia. However, association of the degree of thrombocytopenia with cause of death in AF patients is unknown.

Purpose

We aimed to investigate the association of baseline platelet count with cause of death including cardiac death, intracranial death, malignancy, infection, extracranial bleeding death, renal failure death, respiratory failure death and undetermined death.

Methods

The Fushimi AF Registry was designed to enroll all of the AF patients in Fushimi-ku, Kyoto. Fushimi-ku is densely populated with a total population of 283,000 and is assumed to represent a typical urban community in Japan. We started to enroll patients from March 2011, and follow-up data with baseline platelet counts less than 150,000/μL were available in 853 patients by the end of September 2020. We divided them into 3 groups according to baseline platelet level: Mild thrombocytopenia (100,000–149,999/μL, n=703), Moderate thrombocytopenia (50,000–99,999/μL, n=120), and Severe thrombocytopenia (<50,000/μL, n=30).

Results

In the entire cohort, the mean age was 76 years, 34% were women, the mean body weight and body mass index was 59.3 kg and 22.9 kg/m2, and the median platelet count were 121,000/μL (interquartile range 109,000 to 141,000/μL). Compared to Mild thrombocytopenia, patients with Moderate or Severe thrombocytopenia were more likely to have chronic kidney disease (42.2% vs 54.2% vs 73.3%, p=0.0003), have higher HAS-BLED score (1.90 vs 2.14 vs 2.00, p=0.047) and lower hemoglobin (12.8g/dL vs 11.7g/dL vs 11.2g/dL, p<0.0001) and were less often prescribed anti platelet drugs. Age, sex, body weight, systolic blood pressure, previous stroke, previous major bleeding, hypertension, diabetes mellitus, CHADS2 score and CHA2DS2-VASc score were comparable between three groups. During the median follow-up period, the incidence rate (per 100 person-years) of all-cause death was 6.82 vs 15.27 vs 9.64. (p<0.001) On univariate analysis, the incidence of all-cause death was higher in Moderate group than Mild group. (HR: 2.15; 95% CI 1.61–2.87, p<0.0001), but there was no significant difference between Mild and Severe groups. (HR: 1.44; 95% CI 0.78–2.64, p=0.243). The incidence of cardiac death was comparable between three groups. (Mild vs Moderate: HR 0.65; 95% CI 0.15–2.75, p=0.56, Mild vs Severe: HR 1.11; 95% CI 0.15–8.23, p=0.92) Regarding other causes of death such as intracranial bleeding, extracranial bleeding, malignancy, infection, renal failure, respiratory failure and undetermined cause, there was no significant difference.

Conclusion

Mortality was higher according to the degree of thrombocytopenia in AF patients, but the cause of death was not different among three groups.

Funding Acknowledgement

Type of funding sources: None.

Predictors and risk model for heart failure hospitalization in atrial fibrillation patients without pre-existing heart failure: the Fushimi AF Registry

Background

Atrial fibrillation (AF) increases the risk of hospitalization for heart failure (HF), as well as that of thromboembolism. The strategy for prediction of thromboembolism has been well-established; however, little focus has been placed on the risk stratification for and prevention of HF hospitalization in AF patients.

Purpose

The aim of this study is to investigate the predictors and risk model of HF hospitalization in non-valvular AF patients without pre-existing HF.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Kyoto, Japan. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011, and follow-up data were available for 4,472 patients by the end of October 2020. From the registry, we excluded patients without a pre-existing HF (defined as having one of the following; prior hospitalization for HF, New York Heart Association class ≥2, or left ventricular ejection fraction [LVEF] <40%), and those with valvular AF (mitral stenosis or prosthetic heart valve). Among 3,188 non-valvular AF patients without pre-existing HF, we explored the risk factors for the HF hospitalization during follow-up period. The risk model for predicting HF hospitalization was determined by the cumulative numbers of risk factors which were significant on multivariate analysis.

Results

The mean age was 72.4±10.8 years, 1197 were female and 1787 were paroxysmal AF. The mean CHADS2 and CHA2DS2-VASc scores were 1.7±1.2 and 2.9±1.6, respectively. During the median follow-up period of 5.1 years, HF hospitalization occurred in 285 (8.9%), corresponding to an annual incidence of 1.8 events per 100 person-years. In multivariable Cox regression analysis, advanced age (≥75 years), valvular heart disease, coronary artery disease, reduced LVEF (<60%), chronic obstructive pulmonary disease (COPD) and anemia were independently associated with the higher incidence of HF hospitalization (all P<0.001) (Picture 1). A risk model based on these 6 variables could stratify the incidence of HF hospitalization during follow-up period (log-rank; P<0.001) (Picture 2). Patients with ≥3 risk factors had an 11-fold higher incidence of HF hospitalization compared with those not having any of these risk factors (hazard ratio: 11.3, 95% confidence interval: 7.0–18.4; P<0.001).

Conclusions

Advanced age, coronary artery disease, valvular heart disease, reduced LVEF, COPD and anemia were independently associated with the risk of HF hospitalization in AF patients without pre-existing HF. There was good prediction for endpoint of HF hospitalization using these 6 variables, providing the opportunities for the implementation of strategies to reduce the incidence of HF among AF patients.

Funding Acknowledgement

Type of funding sources: None.

Derivation and validation of a novel score to detect heart failure with preserved ejection fraction in patients with atrial fibrillation: the Fushimi AF registry

Background

Heart failure with preserved ejection fraction (HFpEF) is an important comorbidity of atrial fibrillation (AF). However, it is sometimes difficult to detect HFpEF among AF patients with preserved EF, since AF and HF share similar symptoms.

Purpose

The aim of this study was to identify factors associated with having HFpEF in AF patients with preserved EF, and derive a new score for HFpEF in AF patients.

Methods

The Fushimi AF Registry is a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto, Japan. Follow-up data were available for 4,466 patients, and 3,083 patients had preserved EF (≥50%). Of the 3,083 patients, 444 had prior HF hospitalization at baseline and we defined these patients as HFpEF. We examined the factors associated with having HFpEF, and derived a new score for detecting HFpEF in AF patients. Thereafter, we validated this score in patients without prior HF hospitalization.

Result

The mean age of the patients with EF ≥50% was 73.6 years, and 41.3% were female. Compared with the patients without prior HF hospitalization, HFpEF patients were older, more often female, less in body weight, had more heart disease (valvular heart disease, cardiomyopathy, old myocardial infarction, and coronary artery disease), chronic kidney diseases (CKD), anemia (Hb <11 g/dL), sustained AF (persistent or permanent), left atrial enlargement (>45 mm), and dilation of cardio-thoracic ratio (CTR) (>54%) at baseline. In multivariate analysis, heart diseases, CKD, sustained AF, dilatation of CTR, left atrial enlargement, and anemia were significantly associated with HFpEF (Table 1). We derived a new score to diagnose HFpEF in AF patients (2 points for heart diseases, 1 point for CKD, sustained AF, dilatation of CTR, left atrial enlargement, and anemia; range 0 to 7 points). In a receiver-operating characteristic curve, optimal cut-off point for detecting HFpEF was 3 (Figure 1). We validated this score in patients without prior hospitalization for HF (n=2,639). Of these, 298 patients had HF symptoms of NYHA 2–4 (Symptomatic-HF), and 2,341 patients had neither prior HF hospitalization nor HF symptoms (No-HF). Notably, 207 patients (69.5%) in symptomatic-HF group and 748 patients (32.0%) in No-HF group were classified into HFpEF based on this new score. Furthermore, patients diagnosed as HFpEF by this score had higher incidence of new hospitalization for HF during the follow-up in both symptomatic-HF group and No-HF group. (Figure 2).

Conclusion

We derived a new score to diagnose HFpEF in AF patients based on the presence of prior HF hospitalization (2 points for heart diseases, 1 point for CKD, sustained AF, dilatation of CTR, left atrial enlargement, and anemia). In patients without prior HF hospitalization, sizable number of patients had high HFpEF score (≥3), and those patients showed higher incidence of new HF hospitalization.

Funding Acknowledgement

Type of funding source: None

Clinical outcomes of Japanese atrial fibrillation patients with combined valvular heart disease: the Fushimi AF Registry

Background

We previously reported that valvular heart disease (VHD) was not at the significant risk of stroke/systemic embolism (SE), but was associated with an increased risk of hospitalization for heart failure (HF) in Japanese atrial fibrillation patients. However, the impact of combined VHD on clinical outcomes has been little known.

Purpose

The aim of this study is to investigate the prevalence of combined VHD and its clinical characteristics and impact on outcomes such as stroke/SE, all-cause death, cardiac death and hospitalization for HF.

Method

The Fushimi AF Registry is a community-based prospective survey of AF patients in one of the wards of our city which is a typical urban district of Japan. We started to enroll patients from March 2011, and follow-up data were available for 4,466 patients by the end of November 2019. In the entire cohort, echocardiography data were available for 3,574 patients. 68 AF patients with prosthetic heart valves were excluded and we compared clinical characteristics and outcomes between 488 single VHD (103 Aortic valve disease (AVD), 315 mitral valve disease (MVD), 70 tricuspid valve disease (TVD)) and 158 combined VHD (46 AVD and MVD, 11 AVD and TVD, 66 MVD and TVD, 35 AVD and MVD and TVD).

Result

Compared with single VHD, patients with combined VHD were older (combined vs. single VHD: 78.5 vs. 76.0 years, respectively; p<0.01), more likely to have persistent/permanent type AF (73.4% vs. 63.9%, p=0.02) and prescription of warfarin (63.1% vs. 53.8%, p=0.04). Combined VHD was less likely to have diabetes mellitus (13.9% vs. 23.6%, p=0.01) and dyslipidemia (26.6% vs. 40.4%, p<0.01). Sex, body weight, hypertension, pre-existing HF were comparable between the two groups.

During the median follow-up of 1,474 days, the incidence rate of stroke/SE was not significantly different between the two groups (1.58 vs. 1.89 per 100 person-years, respectively, log rank p=0.10). The incidence rate of all-cause death (7.35 vs. 5.33, p=0.65), cardiac death (1.20 vs. 0.99, p=0.91) and hospitalization for HF (5.55 vs. 4.43, p=0.53) were also not significantly different. We previously reported AVD had significant impacts on cardiac adverse outcomes in AF patients, and we further analyzed event rates between combined VHD including AVD (AVD and MVD/TVD) and without AVD (MVD and TVD). Combined VHD with AVD group had higher incidence rate of all-cause death (10.7 vs. 5.79, p=0.03) than that without AVD group. However, the incidence rate of stroke/SE (1.98 vs. 1.56, p=0.59), cardiac death (0.98 vs. 1.14, p=0.68), hospitalization for HF (8.03 vs. 5.38, p=0.17) were not significantly different between the two groups.

Conclusion

As compared with single VHD, the risk of stroke/SE, all-cause death, cardiac death and hospitalization for HF in combined VHD was not significantly different. Among patients with combined VHD, those having AVD had higher incidence rate of all-cause death than those without AVD.

Figure 1

Funding Acknowledgement

Type of funding source: None

The relationship between diastolic blood pressure and the risk of cardiovascular events in patients with atrial fibrillation: the Fushimi AF registry

Background

Hypertension is one of the major risk factors of cardiovascular events in patients with atrial fibrillation (AF). However, relationship between diastolic blood pressure (DBP) and cardiovascular events in AF patients remains unclear.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in Japan. Follow-up data were available in 4,466 patients, and 4,429 patients with available data of DBP were examined. We divided the patients into three groups; G1 (DBP<70 mmHg, n=1,946), G2 (70≤DBP<80, n=1,321) and G3 (80≤DBP, n=1,162), and compared the clinical background and outcomes between groups.

Results

The proportion of female was grater in G1 group, and the patients in G1 group were older and had higher prevalence of heart failure (HF), diabetes mellitus (DM), chronic kidney disease (CKD). Prescription of beta blockers was higher in G1 group, but that of renin-angiotensin system-inhibitors and calcium channel blocker was comparable. During the median follow-up of 1,589 days, in Kaplan-Meier analysis, the incidence rates of cardiovascular events (composite of cardiac death, ischemic stroke and systemic embolism, major bleeding and HF hospitalization during follow up) were higher in G1 group and G3 group than G2 group (Figure 1). When we divided the patients based on the systolic blood pressure (SBP) at baseline (≥130 mmHg or <130 mmHg), the incidence of rates of cardiovascular events were comparable among groups. Multivariate Cox proportional hazards regression analysis including female gender, age (≥75 years), higher SBP (≥130 mmHg), DM, pre-existing HF, CKD, low left ventricular ejection fraction (<40%) and DBP (G1, G2, G3) revealed that DBP was an independent determinant of cardiovascular events (G1 group vs. G2 group; hazard ratio (HR): 1.40, 95% confidence intervals (CI): 1.19–1.64, G3 group vs. G2 group; HR: 1.23, 95% CI: 1.01–1.49). When we examined the impact of DBP according to 10 mmHg increment, patients with very low DBP (<60 mmHg) (HR: 1.50,95% CI:1.24–1.80) and very high DBP (≥90 mmHg) (HR: 1.51,95% CI:1.15–1.98) had higher incidence of cardiovascular events than patients with DBP of 70–79 mmHg (Figure 2). However, when we examined the impact of SBP according to 20 mmHg increment, SBP at baseline was not associated with the incidence of cardiovascular events (Figure 3).

Conclusion

In Japanese patients with AF, DBP exhibited J curve association with higher incidence of cardiovascular events.

Funding Acknowledgement

Type of funding source: None

Adverse outcomes after worsening renal function in patients with atrial fibrillation: the Fushimi AF Registry

Background

Patients with atrial fibrillation (AF) commonly coexist with chronic kidney disease (CKD). Non-vitamin K antagonist oral anticoagulants (NOAC) are recommended for stroke prevention in patients with non-valvular atrial fibrillation (AF), and worsening renal function (WRF) as well as CKD is an important issue in using NOAC. However, little is known about the clinical outcomes of patients after WRF.

Purpose

We aimed to investigate outcomes after WRF in AF patients.

Methods

The Fushimi AF Registry is a community-based prospective survey of the AF patients in our city. Follow-up data including prescription status were available for 4,441 patients. Of them, 1,890 patients who have baseline and at least 1 follow-up creatinine clearance (CrCl) measurements, estimated by the Cockcroft-Gault formula, were analyzed in the present study. WRF was defined as a decrease of ≥20% from baseline CrCl measurement at any time point during follow-up. We evaluated demographics and outcomes after WRF in AF patients.

Results

During the median follow-up period of 2,194 days, mean CrCl decrease of 2.2 ml/min/year was observed and WRF occurred in 981 patients (51.9%). Patients with WRF were significantly more often female (with vs. without WRF; 40.3% vs. 35.4%; p=0.03), older (73.4 vs. 71.1 years of age; p<0.01), more often paroxysmal type (49.9% vs. 47.1%; p<0.01), and more likely to have prior stroke (17.9% vs. 12.7%; p<0.01), heart failure (30.8% vs. 24.8%; p<0.01), diabetes (31.7% vs. 27.1%; p=0.03), and coronary artery disease (19.9% vs. 12.1%; p<0.01) than those without WRF. Co-existing of CKD and mean CrCl at baseline were comparable (37.4% vs. 36.9%; p=0.82, 65.3 vs. 63.5 ml/min; p=0.66, respectively). Mean CHA2DS2-VASc score was significantly higher in WRF patients (3.55 vs. 3.03; p<0.01). On landmark analysis, all-cause mortality occurred in 135 patients (8.6 /100 person-years) after WRF and 82 patients (1.7 /100 person-years) without WRF, with an adjusted hazard ratio (HR) of 6.33 (95% confidence interval [CI], 4.33–9.50; p<0.01), adjusted by sex, age, body weight, serum creatinine, type of AF, oral anticoagulant prescription and comorbidities. Stroke or systemic embolism occurred in 45 patients after WRF (3.0 /100 person-years) and 78 (1.7 /100 person-years) patients without WRF (adjusted HR 1.60 [95% CI, 1.04–2.49; p=0.03]) (Figure).

Conclusions

AF patients after WRF had higher incidence of various adverse events.

Incidence of Adverse Outcomes

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): The Practical Research Project for Life-Style related Diseases including Cardiovascular Diseases and Diabetes Mellitus from Japan Agency for Medical Research and Development. Boehringer Ingelheim, Bayer Healthcare, Pfizer, Bristol-Myers Squibb, Astellas Pharma, AstraZeneca, Daiichi-Sankyo, Novartis Pharma, MSD, Sanofi-Aventis, and Takeda Pharmaceutical.

Clinical impact of regression from sustained to paroxysmal atrial fibrillation: the Fushimi AF registry

Background

Atrial fibrillation (AF) commonly progresses from paroxysmal type to sustained type in the natural course of the disease, and we previously demonstrated that the progression of AF was associated with increased risk of clinical adverse events. There are some patients, though less frequently, who regress from sustained to paroxysmal AF, but the clinical impact of the regression of AF remains unknown.

Purpose

We sought to investigate whether regression from sustained to paroxysmal AF is associated with better clinical outcomes.

Methods

Using the dataset of the Fushimi AF Registry, patients who were diagnosed as sustained (persistent or permanent) AF at baseline were studied. Conversion of sustained AF to paroxysmal AF during follow-up was defined as regression of AF. Major adverse cardiac events (MACE) were defined as the composite of cardiac death, stroke, and hospitalization for heart failure (HF). Event rates were compared between the patients with and without regression of AF. In patients with sustained AF at baseline, predictors of MACE were identified using Cox proportional hazards model.

Results

Among 2,253 patients who were diagnosed as sustained AF at baseline, regression of AF was observed in 9.0% (202/2,253, 2.0 per 100 patient-years) during a median follow-up of 4.0 years. Of these, 24.3% (49/202, 4.6 per 100 patient-years) of the patients finally recurred to sustained AF during follow-up. The proportion of asymptomatic patients was lower in patients with regression of AF than those without (with vs without regression; 49.0% vs 69.5%, p<0.01). The percentage of beta-blocker use at baseline was similar between the two groups (37.2% vs 33.8%, p=0.34). The prevalence of patients who underwent catheter ablation or electrical cardioversion during follow-up was higher in patients with regression of AF (catheter ablation: 15.8% vs 5.5%; p<0.01, cardioversion: 4.0% vs 1.4%; p<0.01, respectively). The rate of MACE was significantly lower in patients with regression of AF as compared with patients who maintained sustained AF (3.7 vs 6.2 per 100 patient-years, log-rank p<0.01). Figure shows the Kaplan-Meier curves for MACE, cardiac death, hospitalization for heart failure, and stroke. In patients with sustained AF at baseline, multivariable Cox proportional hazards model demonstrated that regression of AF was an independent predictor of lower MACE (adjusted hazard ratio [HR]: 0.50, 95% confidence interval [CI]: 0.28 to 0.88, p=0.02), stroke (HR: 0.51, 95% CI: 0.30 to 0.88, p=0.02), and hospitalization for HF (HR: 0.50, 95% CI: 0.29 to 0.85, p=0.01).

Conclusion

Regression from sustained to paroxysmal AF was associated with a lower incidence of adverse cardiac events.

Funding Acknowledgement

Type of funding source: None

Plasma natriuretic peptide level is an independent determinant of major clinical outcomes in atrial fibrillation patients without heart failure: the Fushimi AF Registry

Background

Atrial fibrillation (AF) increases the risk of death, stroke/systemic embolism and heart failure (HF). Plasma natriuretic peptide (NP) level is an important prognostic marker in HF patients. However, little is known regarding the prognostic significance of plasma NP level in AF patients without HF.

Purpose

The aim of this study is to investigate the relationship between plasma NP level and clinical outcomes such as all-cause death, stroke/systemic embolism and HF hospitalization during follow-up period in AF patients without HF.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in our city. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011, and follow-up data were available for 4,466 patients by the end of November 2019. From the registry, we excluded 1,220 patients without a pre-existing HF (defined as having one of the following; prior hospitalization for HF, New York Heart Association class ≥2, or left ventricular ejection fraction <40%). Among 3,246 AF patients without HF, we investigated 1,189 patients with the data of plasma BNP (n=401) or N-terminal pro-BNP (n=788) level at the enrollment. We divided the patients according to the quartile of each plasma BNP or NT-pro BNP level and compared the backgrounds and outcomes between these 4 groups stratified by plasma NP level.

Results

Of 1,189 patients, the mean age was 72.1±10.2 years, 454 (38%) were female and 684 (58%) were paroxysmal AF. The mean CHADS2 and CHA2DS2-VASc score were 1.6±1.1 and 2.9±1.5, respectively. Oral anticoagulants were prescribed in 671 (56%) at baseline. The median (interquartile range) BNP and N-terminal pro-BNP level were 84 (38, 176) and 500 (155, 984) pg/ml, respectively. Patients with high plasma NP level were older, and demonstrated lower prevalence of paroxysmal AF, higher CHADS2 and CHA2DS2-VASc scores and higher prevalence of chronic kidney disease and oral anticoagulants prescription (all P<0.01). A total of 165 all-cause death, 114 stroke/systemic embolism and 103 HF hospitalization occurred during the median follow-up period of 5.0 years. Kaplan-Meier curves demonstrated that higher plasma NP level was significantly associated with the incidences of all-cause death, stroke/systemic embolism and HF hospitalization in AF patients without HF (Figure 1A). Multivariable Cox regression analysis revealed that plasma NP level could stratify the risk of clinical outcomes even after adjustment by type of AF, CHA2DS2-VASc score, chronic kidney disease and oral anticoagulant prescription (Figure 1B).

Conclusion

Plasma NP level is a significant prognostic marker for all-cause death, stroke/systemic embolism and HF hospitalization in AF patients without HF, suggesting the importance of measuring plasma NP level in AF patients even without HF.

Figure 1

Funding Acknowledgement

Type of funding source: None

Splice-site mutations in KIF5A in the Japanese case series of amyotrophic lateral sclerosis

Our objective was to investigate the frequency of KIF5A variants in amyotrophic lateral sclerosis (ALS) and the clinical characteristics of familial ALS (FALS) associated with variants in KIF5A. Whole-exome sequence analysis was performed for a Japanese series of 43 families with FALS and 444 patients with sporadic ALS (SALS), in whom causative variants had not been identified. We compared the frequencies of rare variants (MAF < 0.01) in KIF5A, including missense and loss of function (LoF) variants, between ALS and control subjects (n = 1163). Clinical characteristics of patients with FALS carrying pathogenic variants in KIF5A were also described. LoF variants were identified only in the probands of two families with FALS, both of which were 3' splice-site variants leading to exon skipping and an altered C-terminal domain, located in the mutational hotspot causing FALS, and were considered to be pathogenic for FALS. Rare missense variants in KIF5A were identified in five patients with SALS (1.13%) and 11 control subjects (0.95%, carrier frequency), which were not significantly different. Consequently, the pathogenic LoF variants in KIF5A accounted for 2.1% of all FALS families in this study. These patients suffered from ALS characteristically associated with the predominant involvement of upper motor neuron. In conclusion, we identified two pathogenic splice-site variants in KIF5A in the probands in two Japanese families with FALS, which altered the C-terminal region of KIF5A. Our findings broaden the phenotype spectrum of ALS associated with variants in KIF5A in the Japanese series.

Rocuronium priming for tracheal intubation in COVID-19 patients

Priming doses of non-depolarising neuromuscular blocking drugs given before administration of anaesthetic agents have been used to hasten the onset of neuromuscular blockade. In the settings of coronavirus disease 2019 (COVID-19), this could be used to reduce the apnoeic, and potentially aerosol-generating, window. To our knowledge, we report the first cases of tracheal intubation with rocuronium for COVID-19 using the priming principle. Both patients needed their tracheas intubated for severe hypoxia using a rapid sequence induction technique with a priming dose of rocuronium. Despite adequate pre-oxygenation a sudden, unexpected fall in arterial oxygen saturations was observed in both patients after administration of a priming dose of 2 mg of rocuronium. Clinicians should consider this possible risk associated with priming doses of neuromuscular blocking drugs in the management of patients with respiratory failure due to COVID-19.

Comprehensive investigation of RNF213 nonsynonymous variants associated with intracranial artery stenosis

Intracranial artery stenosis (ICAS) is the most common cause of ischemic stroke worldwide. RNF213 single nucleotide variant c.14429G > A (p.Arg4810Lys, rs112735431) was recently reported to be associated with ICAS in East Asians. However, the disease susceptibility of other RNF213 variants has not been clarified. This study comprehensively investigated ICAS-associated RNF213 variants in a pool of 168 Japanese ICAS patients and 1,194 control subjects. We found 138 nonsynonymous germline variants by target resequencing of all coding exons in RNF213. Association study between ICAS patients and control subjects revealed that only p.Arg4810Lys had significant association with ICAS (P = 1.5 × 10^-28, odds ratio = 29.3, 95% confidence interval 15.31-56.2 [dominant model]). Fourteen of 138 variants were rare variants detected in ICAS patients not harboring p.Arg4810Lys variant. Two of these rare variants (p.Cys118Arg and p.Leu2356Phe) consistent with variants previously reported in moyamoya disease patients characterized by stenosis of intracranial artery and association with RNF213, and three rare variants (p.Ser193Gly, p.Val1817Leu, and p.Asp3329Tyr) were found neither in control subjects and Single Nucleotide Polymorphism Database. The present findings may improve our understanding of the genetic background of intracranial artery stenosis.

Assessment of the difference limens for frequency, monosyllable articulation and word intelligibility by distantly-presented bone-conducted ultrasound. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020;2020:3877-3880. [PMID: 33018847 DOI: 10.1109/embc44109.2020.9176626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Ultrasound can be clearly perceived by bone-conduction, and this "bone-conducted ultrasound (BCU)" can transmit speech information by using amplitude modulation (AM). Further, BCU can be perceived not only on the head but also on the distal parts of the body like the neck, trunk and arms. This "distantly-presented BCU" can be applied to the novel interface that can transmit sound information selectively to specific users who touches the vibrator. However, the ability to transmit sound information of distantly-presented BCU is unclear. First, to assess frequency discrimination ability, difference limens for frequency (DLFs) of the distantly-presented AM-BCU were measured with/without a low-pass masking noise that masked the self-demodulated components generated by the nonlinearity of biological tissues. DLFs comparable to that of air-conducted sounds were observed, whereas DLFs significantly increased above 1 kHz under the masking condition. These results suggest that practical frequency discrimination ability can be obtained even when BCUs were presented to distal body parts. Additionally, it is indicated that the demodulated components may contribute to transmitting frequency information above 1 kHz. Second, monosyllable articulation and word intelligibility tests were conducted in Japanese. The intelligibility and articulation at the neck were 55% and 38% respectively, whereas they decreased as the stimulus placement gets farther from the head. The results suggest the distantly-presented BCU device can be applied to transmission of speech information.

AB1103 AUTOMATIC FINGER JOINT BONE EROSION SCORE PREDICTION CONSIDERING 2-TIME-POINT X-RAYS OF PATIENTS WITH RHEUMATOID ARTHRITIS BY DEEP LEARNING

Background:

Medical image analysis using deep learning (DL) has been attracting attention. In previous research, we proposed a DL method for detection of joint region and evaluation for bone destruction at a single point in time in hand X-rays of patients with rheumatoid arthritis (RA) [1-2]. However, in the score of van der Heijde-modified total Sharp scores (mTSS) in X-rays, it is difficult to apply the method as it is. In mTSS, score difference between 2-time points is important, and there is a problem that the score at each time varies depending on the doctor who evaluates.

Objectives:

We aimed at developing an mTSS scoring method considering 2-time-point difference with a DL method.

Methods:

A total of 104 X-ray image sets of both hands at two time points with an interval of ≥1 year were randomly obtained from patients with RA who had visited our clinic in 2015. Well-trained doctors determined the erosion scores of MP and PIP/IP joints of each hand in X-rays according to mTSS. These evaluations of hand joints were performed using our developed annotation software tool. In the learning phase, joint images were randomly divided into five sets for 5-fold cross-validation. We utilized a convolutional neural network model, such as SSD [3], for detecting joint regions and classifying the scores (Fig 1).

Figure1.

The models for classification were designed in consideration of the difference in erosion scores of each patient between the 2-time points of X-rays. The loss function of the DL model was defined bellow;

Here, the coefficient γ is designed to reduce the error for another set of scores with equal differences. The first term of the loss function works to optimize the score at each time point, and the second term works to optimize the score difference at both time points. Thus, our method can be trained without being affected by characteristic training data.

Results:

The number of joints with differences in erosion score between the former and latter time points was 1 (-2 points), 9 (-1), 2015 (0), 32 (+1), 17 (+2), and 6 (+3). There were no joints with score changes of -5, -4, -3, +4, and +5 points.

As a performance of predicting the difference in erosion score between the 2-time points of each patient’s X-ray, our models presented a mean error of 0.412 per each joint in one set for 5-cross validation as compared with physicians’ evaluation (Fig 2).

Figure 2.

Conclusion:

Our DL-based models to predict hand joint erosion scores in X-rays were developed with relatively small samples. This suggests that the predictive performance may increase by collecting more training dataset. Next, we will apply our method to the prediction of joint space narrowing score.

References:

[1]Izumi K, Hashimoto M, Suzuki K, et al. Detecting Hand Joint Ankylosis in Radiographic Images Using Deep Learning: A Step in Developing Automatic Radiographic Scoring System for Bone Destruction.Arthritis Rheumatol2018;70 (suppl 10).

[2]Izumi K, Suzuki K, Hashimoto M, et al. SAT0543 AUTOMATIC DETECTION OF HAND JOINT REGION, ANKYLOSIS AND SUBLUXATION IN RADIOGRAPHIC IMAGES USING DEEP LEARNING: DEVELOPMENT OF ARTIFICIAL INTELLIGENCE-BASED RADIOGRAPHIC EVALUATION SYSTEM FOR BONE DESTRUCTION.Annals of the Rheumatic Diseases2019;78 (suppl 2), pp. 1364-1364.

[3]Liu W, Anguelov D, Szgedy C, et al. SSD: single shot multibox detector.European Conference on Computer Vision (ECCV) 2016.

Acknowledgments:

Izumi and Suzuki are contributed equally.

Disclosure of Interests:

Keisuke Izumi Grant/research support from: Asahi Kasei Pharma, Takeda Pharmaceutical Co., Ltd., Speakers bureau: Asahi Kasei Pharma Corp, Astellas Pharma Inc., Bristol Myers Squibb, Chugai Pharmaceutical Co., Ltd., Eli Lilly Japan K.K., Mitsubishi Tanabe Pharma Co., Kanata Suzuki Employee of: Fujitsu Laboratories Ltd., Masahiro Hashimoto: None declared, Toshio Endoh Employee of: Fujitsu Laboratories Ltd., Kentaro Doi Employee of: Fujitsu Ltd., Yuki Iwai Employee of: Fujitsu Ltd., Yuko Kaneko Speakers bureau: AbbVie, Eisai Pharmaceutical, Chugai Pharmaceutical Co., Ltd., Bristol Myers Squibb, Astellas Pharma Inc., Mitsubishi Tanabe Pharma Co., Pfizer Japan Inc., Janssen Pharmaceutical K.K., Eli Lilly Japan K.K., Santen Pharmaceutical Co., Ltd., Kyowa Hakko Kirin Co. Ltd. and UCB Japan Co. Ltd., Masahiro Jinzaki: None declared, Shigeru Ko Grant/research support from: Fujitsu Ltd., Tsutomu Takeuchi Grant/research support from: Astellas Pharma Inc, Chugai Pharmaceutical Co, Ltd., Daiichi Sankyo Co., Ltd., Takeda Pharmaceutical Co., Ltd., AbbVie GK, Asahikasei Pharma Corp., Mitsubishi Tanabe Pharma Co., Pfizer Japan Inc., Eisai Co., Ltd., AYUMI Pharmaceutical Corporation, Nipponkayaku Co. Ltd., Novartis Pharma K.K., Teijin, Consultant of: Astra Zeneca K.K., Eli Lilly Japan K.K., Novartis Pharma K.K., Mitsubishi Tanabe Pharma Co., Abbivie GK, Nipponkayaku Co.Ltd, Janssen Pharmaceutical K.K., Astellas Pharma Inc., Taiho Pharmaceutical Co. Ltd., Chugai Pharmaceutical Co. Ltd., Taisho Toyama Pharmaceutical Co. Ltd., GlaxoSmithKline K.K., UCB Japan Co. Ltd., Speakers bureau: Astellas Pharma Inc., Bristol Myers Squibb, Chugai Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Co., Pfizer Japan Inc., Santen Pharmaceutical Co., Ltd., Takeda Pharmaceutical Co., Ltd., Teijin Pharma Ltd., AbbVie GK, Asahi Kasei Pharma Corp., Taisho Toyama Pharmaceutical Co., Ltd., SymBio Pharmaceuticals Ltd., Janssen Pharmaceutical K.K., Celltrion Inc., Nipponkayaku Co. Ltd., and UCB Japan

Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA

We present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star-black hole, and binary black hole systems. The ability to localize the sources is given as a sky-area probability, luminosity distance, and comoving volume. The median sky localization area (90% credible region) is expected to be a few hundreds of square degrees for all types of binary systems during O3 with the Advanced LIGO and Virgo (HLV) network. The median sky localization area will improve to a few tens of square degrees during O4 with the Advanced LIGO, Virgo, and KAGRA (HLVK) network. During O3, the median localization volume (90% credible region) is expected to be on the order of 10 5 , 10 6 , 10 7 Mpc 3 for binary neutron star, neutron star-black hole, and binary black hole systems, respectively. The localization volume in O4 is expected to be about a factor two smaller than in O3. We predict a detection count of 1 - 1 + 12 ( 10 - 10 + 52 ) for binary neutron star mergers, of 0 - 0 + 19 ( 1 - 1 + 91 ) for neutron star-black hole mergers, and 17 - 11 + 22 ( 79 - 44 + 89 ) for binary black hole mergers in a one-calendar-year observing run of the HLV network during O3 (HLVK network during O4). We evaluate sensitivity and localization expectations for unmodeled signal searches, including the search for intermediate mass black hole binary mergers.

Oral steroid decreases the progression of joint destruction of large joints in the lower extremities in rheumatoid arthritis

To identify the risk factors for destruction of large joints in the lower extremities in patients with rheumatoid arthritis (RA) during a 4-year follow-up period in a prospective study.We enrolled consecutive patients who participated in both 2012 and 2016. Clinical data, disease activity, and types of medication were collected in 2012. Standard anteroposterior radiographs of weight-bearing joints (hips, knees, and ankles) were taken in 2012 and 2016. Radiographic progression was defined as progression in the Larsen grade or the need for joint arthroplasty or arthrodesis. The association between baseline characteristics and the incidence of radiographic progression was statistically assessed.A total of 213 patient were enrolled, and, after exclusion, 186 patients were analyzed. Sixty 9 patients (37.1%) showed radiographic progression in 1 of the large joints in the lower extremities. Multivariate regression analysis showed that radiographic progression was associated with older age, higher disease activity, and the presence of radiographic destruction at the baseline. The lower dosage of oral prednisolone was a significant risk factor compared with higher dosage when used.Patients with the risk factors should be followed closely to limit the progression of large joint destruction in the lower extremities.

P3771Validation of risk scoring system predicting for progression of atrial fibrillation: the Fushimi AF Registry

Background

Atrial fibrillation (AF) increases the risks of thromboembolism and death. Progression from paroxysmal to sustained types (persistent or permanent) of AF is sometimes seen in clinical practice. We recently reported that progression of AF was associated with increased risk of clinical adverse events in Japanese AF patients. However, risk stratification schemes of predicting the progression of AF has not been fully established.

Methods

The Fushimi AF Registry, a community-based prospective survey, was designed to enroll all of the AF patients in Fushimi-ku, Kyoto, which is a typical urban district of Japan with a population of 283,000. Follow-up data were available for 4,454 patients. We investigated the risk factors of AF progression and validated the performance of various risk scoring systems predicting for progression of AF, such as APPLE, BASE-AF2, HATCH, and MB-LATER score, using data from 995 paroxysmal AF patients (mean age; 72.6±11.4 years, female; 42.2%, mean CHA2DS2-VASc score; 3.26±1.67) whose echocardiogram data were obtained at baseline.

Results

Of 995 AF patients, during the median follow-up of 1,477 days, progression from paroxysmal to sustained AF occurred in 160 patients (16.1%; 4.0 per 100 person-years). On a multivariate model, we indicated that history of AF ≥2 years (odds ratio [OR] 1.83; 95% confidence interval [CI] 1.28–2.61), left atrial diameter ≥40 mm (OR 1.45; 95% CI 1.02–2.08), daily drinker (OR 1.56; 95% CI 1.24–2.81), and cardiomyopathy (OR 2.58; 95% CI 1.17–5.69) were significantly associated with higher incidence of AF progression. Our model had better predictive potential for AF progression (area under curve [AUC] 0.612; 95% CI 0.566–0.658) than the APPLE (AUC 0.553; 95% CI 0.508–0.598; p=0.06), BASE-AF2 (AUC 0.571; 95% CI 0.526–0.617; p=0.04), CHADS2 (AUC 0.508; 95% CI 0.462–0.554; p<0.01), CHA2DS2-VASc (AUC 0.501; 95% CI 0.453–0.548; p<0.01), HATCH (AUC 0.502; 95% CI 0.456–0.548; p<0.01), and MB-LATER (AUC 0.528; 95% CI 0.483–0.572; p<0.01) score.

Conclusion

We identified 4 risk factors which may be useful to predict for progression of AF in Japanese patients. External validation of our model in other cohorts is needed.

Acknowledgement/Funding

Boehringer, Bayer, Pfizer, Bristol-Myers, Astellas, AstraZeneca, Daiichi Sankyo, Novartis, MSD, Sanofi and Takeda. Japan Agency for Medical Research

P3780Clinical characteristics and outcomes in Japanese atrial fibrillation patients with valvular heart disease: the Fushimi AF registry

Background

Previous studies have suggested that valvular atrial fibrillation (VAF), defined as atrial fibrillation (AF) patients with prosthetic valve or rheumatic mitral stenosis, increased the risks of thromboembolism. However, clinical characteristics and outcomes of VAF and non-valvular AF (NVAF) patients with other valvular heart disease (VHD) has not been fully described.

Method

The Fushimi AF Registry was designed to enroll all of the AF patients. In the entire cohort (4,454 patients), follow-up data including echocardiography data were available for 3,566 patients. We compared clinical characteristics and outcomes between 131 VAF patients (3.7%), 583 NVAF with VHD (NVAF-VHD: 16.3%) and 2,852 without VHD (Non-VHD: 80.0%).

Result

Compared with Non-VHD, patients in VAF and NVAF-VHD were older (VAF vs. NVAF-VHD vs. Non-VHD: 74.3 vs. 76.9 vs. 72.9 years, respectively; p≤0.0001), more often female (56.5% vs. 51.1% vs. 36.9%, p≤0.0001), less in body weight (54.3 vs. 54.7 vs. 60.6 kg, p≤0.0001), more persistent/permanent type (64.1% vs. 65.4% vs. 45.8%, p≤0.0001), more likely to have heart failure (61.8% vs. 53.2% vs. 23.3%, p≤0.0001), had higher CHADS2 score (2.18 vs. 2.49 vs. 1.96, p≤0.0001) and CHA2DS2-VASc score (3.71 vs. 4.02 vs. 3.26, p≤0.0001), and received oral anticoagulant prescription more frequently (78.6% vs. 63.0% vs. 55.6%, p0.0001). NVAF-VHD was more likely to have previous stroke/systemic embolism (SE) than VHD or Non-VHD (14.5% vs. 23.5% vs. 19.6%, p=0.03). VAF or NVAF-VHD had larger left atrium than Non-VHD (50.5 vs. 47.2 vs. 42.4 mm, p<0.0001). Heart rate, diabetes mellitus and previous bleeding were comparable between the groups.

During the median follow-up of 1,471 days, the incidence rate of stroke/SE was not significantly different between three groups, however, NVAF-VHD showed modestly higher rate than Non-VHD (1.67 vs. 1.96 vs. 1.28 per 100 person-years, respectively, log rank p=0.054) (Figure). The incidence rates of all-cause death (4.62 vs. 5.74 vs. 3.21, p≤0.0001), cardiac death (1.07 vs. 1.01 vs. 0.44, p=0.0003), and those of hospitalization for heart failure (3.29 vs. 4.41 vs. 1.80, p≤0.0001) were higher in NVAF-VHD and VAF, than Non-VHD. After adjustment by relevant factors including the components of CHA2DS2-VASc score and oral anticoagulant use, NVAF-VHD, but not VAF, was an independent predictor for hospitalization for heart failure. Neither VAF nor NVAF-VHD was predictors for all-cause death, cardiac death or stroke/SE.

Figure 1. Incidence of stroke/SE

Conclusion

As compared with Non-VHD, the risk of stroke/SE in VAF and NVAF-VHD was not particularly high; although NVAF-VHD had modestly higher rate than Non-VHD. VAF and NVAF-VHD were associated with higher incidence rates of all-cause death, cardiac death and hospitalization for heart failure. NVAF-VHD was an independent predictor for hospitalization for heart failure in multivariate analysis.

Acknowledgement/Funding

Pfizer, Bristol-Myers Squibb, Boehringer Ingelheim, Bayer Healthcare and Daiichi Sankyo

P5663Impact of proteinuria on cardiovascular outcomes in Japanese diabetic patients with atrial fibrillation: the Fushimi AF Registry

Background

Previous studies have suggested that proteinuria is independently associated with clinical outcomes in diabetic patients, irrespective of the presence of renal dysfunction. However, data regarding the impact of proteinuria on clinical outcomes in diabetic patients with atrial fibrillation (AF) are limited.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in our city in Japan. Follow-up data were available in 4,454 patients, and 634 diabetic patients with available data of proteinuria and estimated glomerular filtration rate (eGFR) were examined. We compared the clinical background and outcomes between patients with proteinuria (n=251) and those without (n=383). Then, we divided the patients into 4 subgroups according to the presence of proteinuria and renal dysfunction, and compared the clinical outcomes between groups; group 1 (without proteinuria, eGFR ≥60 ml/min/1.73 m2; n=203), group 2 (with proteinuria, eGFR ≥60; n=96), group 3 (without proteinuria, eGFR <60; n=180), group 4 (with proteinuria, eGFR <60; n=155).

Results

Age was comparable between patients with or without proteinuria. Patients with proteinuria had higher prevalences of previous heart failure (HF), stroke/systemic embolism, hypertension and renal dysfunction. The prevalences of previous myocardial infarction, and major bleeding were similar between two groups. During the median follow-up of 1,505 days, the incidence rates of HF hospitalization (4.1/100 person-years vs. 2.5/100 person-years; p<0.01) and cardiovascular death (1.8/100 person-years vs. 0.4/100 person-years; p<0.01) were higher in patients with proteinuria. When we divided patients into 4 subgroups, the incidences of HF hospitalization (group 1: 1.8/100 person-years vs. group 2: 3.4/100 person-years vs. group 3: 3.8/100 person-years vs. group 4: 4.9/100 person-years; p<0.01) and cardiovascular death (group 1: 0.3/100 person-years vs. group 2: 1.8/100 person-years vs. group 3: 0.5/100 person-years vs. group 4: 2.2/100 person-years; p<0.01) tended to be higher in not only group 3 and group 4 but also group 2 than group 1 (Figure). Multivariate Cox proportional hazards regression analysis including female gender, age (≥75 years), hypertension, pre-existing HF, renal dysfunction (eGFR <60),low left ventricular ejection fraction (<40%) and proteinuria revealed that proteinuria was an independent determinant of both of HF hospitalization (adjusted hazard ratio [HR]: 1.57, 95% confidence interval [CI]: 1.05–2.34) and cardiovascular death (HR: 3.76, 95% CI: 1.59–8.88).

Figure 1

Conclusion

In Japanese diabetic patients with AF, proteinuria was associated with higher incidences of HF hospitalization and cardiovascular death, irrespective of the presence of renal dysfunction.

P3758Clinical characteristics and outcomes of atrial fibrillation patients with thrombocytopenia: the Fushimi AF Registry

Background

Thrombocytopenia is sometimes found in routine blood tests and is reported as a risk factor of major bleeding events and incidence of all-cause death after percutaneous coronary intervention. However, the influence of thrombocytopenia on clinical outcomes in patients with atrial fibrillation (AF) remains unknown.

Purpose

We aimed to investigate relationship between baseline platelet count and clinical outcomes such as all-cause death, hospitalization for heart failure, and the major bleeding event in AF patients.

Methods

The Fushimi AF Registry was designed to enroll all of the AF patients in Fushimi-ku, Kyoto. Fushimi-ku is densely populated with a total population of 283,000 and is assumed to represent a typical urban community in Japan. Follow-up data with baseline platelet counts were available in 4,179 patients from March 2011 to November 2018. We divided the entire cohort into 3 groups according to baseline platelet level: No thrombocytopenia (≥150,000/μL, n=3,323), Mild thrombocytopenia (100,000–149,999/μL, n=707), and Moderate/severe thrombocytopenia (≤99,999/μL, n=149).

Results

In the entire cohort, the mean age was 73 years, 40% were women, and the mean body weight and body mass index was 59 kg and 23.1 kg/m2, and the median platelet count were 192,000/μL (interquartile range 156,000 to 232,000/μL), respectively.

Compared to No thrombocytopenia, patients with thrombocytopenia were older (No vs. Mild vs. Moderate/severe; 73.3 years vs. 76.5 years vs. 75.8 years, p<0.0001), more likely to have heart failure (27.0% vs. 32.8% vs. 41.6%, p<0.0001), more likely to have chronic renal disease (35.7% vs. 42.6% vs. 57.7%, p<0.0001), and had higher CHADS2 score (2.05 vs. 2.17 vs. 2.34, p=0.0039) and CHA2DS2-VASc score (3.40 vs. 3.52 vs. 3.71, p=0.0416). Patients with thrombocytopenia had lower hemoglobin (13.0 vs. 12.8 vs. 11.6, p<0.0001) than No thrombocytopenia. However, prevalence of previous major bleeding events was comparable between three groups (4.66% vs. 4.67% vs. 5.37%, p=0.92)

On Kaplan-Meier analysis, the incidence of all-cause death was higher in Mild group (hazard ratio [HR] 1.51; 95% confidence interval [CI] 1.28–1.77) and Moderate/severe group (HR 2.97; 95% CI 2.28–3.80) than No group (Figure 1). The incidence of hospitalization for heart failure was higher in Mild group (HR 1.62; 95% CI 1.31–1.99) and Moderate/severe group (HR 2.64; 95% CI 1.76–3.81) than No group (Figure 2). The incidence of major bleeding event was higher in Mild group (HR 1.46; 95% CI 1.11–1.91) and Moderate/severe group (HR 2.45; 95% CI 1.41–3.91) than No group (Figure 3).

Conclusion

Thrombocytopenia in AF patients was associated with higher incidence of all-cause death, hospitalization for heart failure, and major bleeding event in the Fushimi AF Registry.

Acknowledgement/Funding

Pfizer, Bristol-Myers Squibb, Boehringer Ingelheim, Bayer Healthcare,and Daiichi-Sankyo

Distinct biomarkers for different bones in osteoporosis with rheumatoid arthritis

Background

Rheumatoid arthritis (RA) is known to cause secondary osteoporosis and fragility fractures. This study aimed to identify biomarkers predictive of bone mineral density (BMD) change at three anatomical sites in patients with RA.

Methods

We conducted a prospective longitudinal study in patients with RA. In 2012, we recruited 379 patients from an RA cohort, 329 of whom underwent evaluation of blood and urine biomarkers together with measurement of BMD in the lumbar spine, proximal femur, and distal forearm. The BMD in these three regions was reassessed in 2014. We performed multivariate linear regression analysis to identify those factors associated with BMD change.

Results

The averages of age, body mass index, and disease activity score in 28 joints (DAS28) at baseline were 63.2 (minimum to maximum, 32–85), 21.3 (12.3–30.0), and 3.2 (0.1–5.9), respectively. Univariate analysis showed that the annual BMD change was significantly associated with the use of steroid, bisphosphonate (BP) or vitamin D (VitD), and serum homocysteine in the lumber spine; DAS28, the use of BP or VitD, CRP, and anti-cyclic citrullinated peptide antibody (ACPA) in the proximal femur; and the dosage of MTX, the use of BP or VitD, and serum tartrate-resistant acid phosphatase 5b (TRACP-5b) in the distal forearm, respectively.

Conclusions

Predictive biomarkers for BMD change in RA patients differ at each anatomical site. Practitioners should treat each anatomical site with different markers and prescribe osteoporosis drugs to prevent fractures for RA patients.

Mutations in COA7 cause spinocerebellar ataxia with axonal neuropathy

Several genes related to mitochondrial functions have been identified as causative genes of neuropathy or ataxia. Cytochrome c oxidase assembly factor 7 (COA7) may have a role in assembling mitochondrial respiratory chain complexes that function in oxidative phosphorylation. Here we identified four unrelated patients with recessive mutations in COA7 among a Japanese case series of 1396 patients with Charcot-Marie-Tooth disease (CMT) or other inherited peripheral neuropathies, including complex forms of CMT. We also found that all four patients had characteristic neurological features of peripheral neuropathy and ataxia with cerebellar atrophy, and some patients showed leukoencephalopathy or spinal cord atrophy on MRI scans. Validated mutations were located at highly conserved residues among different species and segregated with the disease in each family. Nerve conduction studies showed axonal sensorimotor neuropathy. Sural nerve biopsies showed chronic axonal degeneration with a marked loss of large and medium myelinated fibres. An immunohistochemical assay with an anti-COA7 antibody in the sural nerve from the control patient showed the positive expression of COA7 in the cytoplasm of Schwann cells. We also observed mildly elevated serum creatine kinase levels in all patients and the presence of a few ragged-red fibres and some cytochrome c oxidase-negative fibres in a muscle biopsy obtained from one patient, which was suggestive of subclinical mitochondrial myopathy. Mitochondrial respiratory chain enzyme assay in skin fibroblasts from the three patients showed a definitive decrease in complex I or complex IV. Immunocytochemical analysis of subcellular localization in HeLa cells indicated that mutant COA7 proteins as well as wild-type COA7 were localized in mitochondria, which suggests that mutant COA7 does not affect the mitochondrial recruitment and may affect the stability or localization of COA7 interaction partners in the mitochondria. In addition, Drosophila COA7 (dCOA7) knockdown models showed rough eye phenotype, reduced lifespan, impaired locomotive ability and shortened synaptic branches of motor neurons. Our results suggest that loss-of-function COA7 mutation is responsible for the phenotype of the presented patients, and this new entity of disease would be referred to as spinocerebellar ataxia with axonal neuropathy type 3.

Burden of rare variants in causative genes for amyotrophic lateral sclerosis (ALS) accelerates age at onset of ALS

OBJECTIVES

To evaluate the burden of rare variants in the causative genes for amyotrophic lateral sclerosis (ALS) on the age at onset of ALS in a Japanese case series.

METHODS

We conducted whole-exome sequencing analysis of 89 families with familial ALS (FALS) and 410 patients with sporadic ALS (SALS) to identify known pathogenic mutations or rare functionally predicted deleterious variants in the causative genes for ALS. Rare variants (minor allele frequency <1%) with scaled Combined Annotation-Dependent Depletion score >20 were defined as rare functionally predicted deleterious variants. The patients with ALS were classified on the basis of the number of pathogenic and/or rare functionally predicted deleterious variants, and the age at onset was compared among the classified groups.

RESULTS

Whole-exome sequencing analysis revealed known pathogenic mutations or rare functionally predicted deleterious variants in causative genes for ALS in 56 families with FALS (62.9%) and 87 patients with SALS (21.2%). Such variants in multiple genes were identified in seven probands with FALS and eight patients with SALS. The ages at onset in the patients with ALS with multiple variants were significantly earlier than those in other patients with ALS. Even when the patients with known pathogenic mutations were excluded, a significantly earlier onset of the disease was still observed in patients with multiple rare functionally predicted deleterious variants.

CONCLUSIONS

A substantial number of patients carried rare variants in multiple genes, and the burden of rare variants in the known causative genes for ALS affects the age at onset in the Japanese ALS series.

Neuroimaging, genetic, and enzymatic study in a Japanese family with a GBA gross deletion

INTRODUCTION

Glucocerebrosidase gene (GBA) variants are associated with Parkinson's disease (PD) and dementia with Lewy bodies (DLB). The molecular mechanisms underlying these diseases with GBA variants, however, are not well understood. In order to determine the effect of a deletion mutation in GBA, we performed a neuroimaging, genetic, and enzymatic study in a Japanese family with a gross deletion of exons 3 to 11 in GBA.

METHODS

We performed [¹²³I] FP-CIT SPECT and [¹²³I] N-isopropyl-p-iodoamphetamine SPECT (IMP-SPECT), and determined GBA expression and glucocerebrosidase (GCase) activity in leukocytes in two GBA-associated PD patients and nine unaffected individuals (including four mutation carriers) in a Japanese family with a heterozygous gross deletion mutation in the GBA gene.

RESULTS

The two PD patients and two of the four clinically unaffected carriers showed decreased [¹²³I] FP-CIT uptake. IMP-SPECT showed a pattern like that in DLB in one patient. When we compared PD patients with GBA mutations with clinically unaffected carriers, there was a poor correlation between the development of PD and the expression level of GBA or GCase activity.

CONCLUSION

We confirmed the gross deletion mutation in the GBA gene, which appeared to be associated with the PD or reduced [¹²³I] FP-CIT in this family. However, since we cannot conclude whether a reduction of GCase activity is directly correlated with the pathogenesis of PD or not, longitudinal follow-up of this family is needed.

An Improved Computer-aided Diagnosis Scheme Using the Nearest Neighbor Criterion for Determining Histological Classification of Clustered Microcalcifications

Objectives : Our purpose was to evaluate the potential usefulness of the nearest neighbor case which was assumed to be the similar case in a CAD scheme for determining the histological classification of clustered microcalcifications.

Methods : Our database consisted of current and previous magnification mammograms obtained from 93 patients before and after three-month follow-up examination. It included 11 invasive carcinomas, 19 noninvasive carcinomas of the comedo type, 25 noninvasive carcinomas of the noncomedo type, 23 mas- topathies, and 15 fibroadenomas. Six objective features on clustered microcalcifications were first extracted from each of the current and the previous images. The nearest neighbor case was then identified by the Euclidean distance in the previous and current feature-space. The histological classification of an unknown new case in question was assumed to be thesame as that of the nearest neighbor case which has the shortest Euclidean distance in our database.

Results : The classification accuracies were 90.9% for invasive carcinoma, 89.5% for noninvasive carcinoma of the comedo type, 96.0% for noninvasive carcinoma of the noncomedo type, 82.6% for mastopathy, and 93.3% for fibroadenoma. These results were substantially higher than those with our previous CAD scheme.

Conclusion : The nearest neighbor criterion was useful in a CAD scheme for determining the histological classification.

Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA

We present possible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron star systems, which are the most promising targets for multi-messenger astronomy. The ability to localize the sources of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and [Formula: see text] credible regions can be as large as thousands of square degrees when only two sensitive detectors are operational. Determining the sky position of a significant fraction of detected signals to areas of 5-[Formula: see text] requires at least three detectors of sensitivity within a factor of [Formula: see text] of each other and with a broad frequency bandwidth. When all detectors, including KAGRA and the third LIGO detector in India, reach design sensitivity, a significant fraction of gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone.

Centromere evolution and CpG methylation during vertebrate speciation

Centromeres and large-scale structural variants evolve and contribute to genome diversity during vertebrate speciation. Here, we perform de novo long-read genome assembly of three inbred medaka strains that are derived from geographically isolated subpopulations and undergo speciation. Using single-molecule real-time (SMRT) sequencing, we obtain three chromosome-mapped genomes of length ~734, ~678, and ~744Mbp with a resource of twenty-two centromeric regions of length 20-345kbp. Centromeres are positionally conserved among the three strains and even between four pairs of chromosomes that were duplicated by the teleost-specific whole-genome duplication 320-350 million years ago. The centromeres do not all evolve at a similar pace; rather, centromeric monomers in non-acrocentric chromosomes evolve significantly faster than those in acrocentric chromosomes. Using methylation sensitive SMRT reads, we uncover centromeres are mostly hypermethylated but have hypomethylated sub-regions that acquire unique sequence compositions independently. These findings reveal the potential of non-acrocentric centromere evolution to contribute to speciation.