Under-Smoothed Kernel Confidence Intervals for the Hazard Ratio Based on Censored Data

2007 ◽  
Vol 49 (3) ◽  
pp. 474-483 ◽  
Author(s):  
Dongsheng Tu
Keyword(s):  
Confidence Intervals ◽  
Censored Data ◽  
Hazard Ratio ◽  
Smoothed Kernel

Influence function-based empirical likelihood for inference of quantile medical costs with censored data

2019 ◽  
Vol 29 (7) ◽  
pp. 1913-1934
Author(s):  
Jenny Jeyarajah ◽  
Guanhao Wei ◽  
Gengsheng Qin
Keyword(s):  
Confidence Intervals ◽  
Censored Data ◽  
Empirical Likelihood ◽  
Influence Function ◽  
Likelihood Ratio Statistic ◽  
Medical Costs ◽  
Finite Sample ◽  
Chi Square ◽  
Coverage Probabilities ◽  
Interval Lengths

In this paper, we propose empirical likelihood methods based on influence function and Jackknife techniques to construct confidence intervals for quantile medical costs with censored data. We show that the influence function-based empirical log-likelihood ratio statistic for the quantile medical cost has a standard Chi-square distribution as its asymptotic distribution. Simulation studies are conducted to compare coverage probabilities and interval lengths of the proposed empirical likelihood confidence intervals with the existing normal approximation-based confidence intervals for quantile medical costs. The proposed methods are observed to have better finite-sample performances than existing methods. The new methods are also illustrated through a real example.

P5431The relationship between pulse rate and the risk of cardiac events in patients with atrial fibrillation: the Fushimi AF registry

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Iguchi ◽  
N Masunaga ◽  
M Ishii ◽  
Y An ◽  
M Esato ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Blood Pressure ◽  
Confidence Intervals ◽  
Pulse Rate ◽  
Cardiovascular Death ◽  
Left Ventricular ◽  
Hazard Ratio ◽  
Cardiac Events ◽  
The Impact

Abstract Background Relationship between pulse rate (PR) and cardiac events in patients with sustained (persistent and permanent) atrial fibrillation (AF) in routine clinical practice remains unclear. Methods The Fushimi AF Registry is a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto. Follow-up data were available for 4,454 patients, and we obtained PR at baseline in 2,209 patients of 2,248 sustained AF patients. We divided these patients into four groups based on their PR; G1 (PR≥100 bpm, n=249), G2 (80 bpm≤PR<100 bpm, n=821), G3 (60 bpm≤PR<80 bpm, n=986), and G4 (PR<60 bpm, n=153), and examined the relationship between PR and cardiac events (composite of cardiovascular death and hospitalization for heart failure (HF)). Results Proportion of female and symptomatic AF were more in G1 group, and diastolic blood pressure was higher in G1 group, despite that systolic blood pressure was similar between the four groups. Prevalence of anemia was higher in G1 group, and that of chronic kidney disease was higher in G4 group. Prevalence of HF and left ventricular dysfunction tended to be higher in G1 group but not statistically significant. Beta-blockers and non-dihydropyridine calcium blockers were more often prescribed in G1 group. During the median follow-up of 1,449 days, cardiac events occurred in 399 patients (358 hospitalization for HF and 41 cardiovascular death). In Kaplan-Meier analysis, the incidence of cardiac events were comparable between the four groups (p=0.3). The incidence of all cause death (p=0.06) and stroke or systemic embolism (p=0.4) was also similar between the four groups. The incidence of cardiac events did not differ between the four groups when we divided the patients based on the presence of HF at baseline, and the incidence of cardiac events was also comparable between the four groups after adjusting potential confounders. However, when we examined the impact of PR according to 10 bpm increment, patients with very low PR (<50 bpm) (hazard ratio [95% confidence intervals], 2.22 [1.04–4.15]) and very high PR (≥110 bpm) (hazard ratio [95% confidence intervals], 1.67 [1.00–2.64]) had higher incidence of cardiac events than patients with PR of 70–79 bpm (Figure). Furthermore, we acquired the annual follow-up data of PR. Mean PR during the follow-up periods was not different between patients with cardiac events and those without (with vs without, 79.5±15.3 bpm vs 79.7±12.7 bpm; p=0.8), whereas maximum PR was less in patients with cardiac events (85.2±17.5 bpm vs 89.3±16.2 bpm; p<0.0001). Patients with maximum PR<60 bpm showed higher incidence of cardiac events, and the incidence of cardiac events was the lowest in patients with maximum PR of 80 to 99 bpm (maximum PR<60 bpm: 31.3%, 60–79 bpm: 24.5%, 80–99 bpm: 14.5%, 100 bpm: 16.1%; P<ehz746.03881). Conclusion PR did not appear to have strong impact on cardiac events in patients with sustained AF. However, low PR might be a risk for developing cardiac events. Acknowledgement/Funding Japan Agency for Medical Research and Development, AMED (15656344, 16768811), Boehringer Ingelheim, Bayer Healthcare, Pfizer, Bristol-Myers Squibb

scholarly journals P298 The long-term impact of persistent pulmonary hypertension in patients undergoing TAVR with a self-expanding valve

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
M Drakopoulou ◽  
S Soulaidopoulos ◽  
G Oikonomou ◽  
P Toskas ◽  
M Xanthopoulou ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Aortic Valve ◽  
Mitral Regurgitation ◽  
Ejection Fraction ◽  
Confidence Intervals ◽  
Hazard Ratio ◽  
Cumulative Mortality ◽  
Risk Of Death ◽  
The Impact

Abstract Background Persistent severe pulmonary hypertension (PH) is considered to negatively affect early and late outcomes of patients undergoing aortic valve surgery. There is limited data however, cincerning the incidence of persistent PH after transcatheter aortic valve replacement (TAVR) and its impact on outcome is limited. Purpose We sought to investigate the impact of persistent PH on clinical outcomes of patients undergoing TAVR with a self-expanding valve. Methods Consecutive patients with severe symptomatic aortic stenosis scheduled for TAVR in our tertiary center were included in the study. Prospectively collected data before and after TAVR were retrospectively analyzed in all patients. Severe PH was defined as systolic pulmonary arterial pressure (sPAP) ≥45mmHg as assessed by echocardiography. For analysis purposes, patients with a sPAP decrease after TAVR to below 45mmHg were compared to patients with persistent PH following TAVR. All outcomes were evaluated according to the VARC-2 criteria. Results In total, 258 patients were included in this study (mean age 80.06 ± 7.50 years old, logEuroscore 24.50 ± 9.70%, NYHA III/IV Class 98.6%). Of these, 149 (57.8%) had sPAP less than 45mmHg and 109 (42.2%) had sPAP above or equal to 45mmHg at baseline. Patients with severe PH were older (81.1 ± 7.0 vs 79.1 ± 7.7, p = 0.034), presented with higher logEuroscore (26.9 ± 9.3% vs 22.5 ± 9.9%, p&lt; 0.001), lower ejection fraction (47.9 ± 9.3% vs 52.2 ± 8.5%, p&lt; 0.001) and higher rates of at least moderate mitral regurgitation (36.7% vs 16.2%, p = 0.002) compared to the group without PH. After TAVR, 161 (62.4%) patients had sPAP less than 45mmHg and 97 (37.6%) had sPAP above 45mmHg. There was a significant decrease of 2.4 ± 12.2mmHg in sPAP post TAVR (p &lt; 0.01). Multivariable analysis (univariate analysis: age, logEuroscore, pre TAVR mitral regurgitation, pre TAVR ejection fraction below 40%) identified pre TAVR ejection fraction below 40% to be the most powerful predictor for persistent PH after TAVR (odds ratio 2.4, 95% confidence interval 1.0.9 – 5.26, p = 0.028). During a mean follow up period of 26.6 ± 26.8, the presence of pre TAVR severe PH was not found to be predictive of cumulative mortality[Hazard Ratio(HR) : 1.57, 95% Confidence Intervals (CI) 0.92 – 2.66, p = 0.09). However, in the same follow up period, patients with persistent PH after TAVR had higher cumulative risk of death compared to patients with sPAP &lt; 45mmHg after TAVR (Hazard Ratio 0.49, 95% Confidence Intervals 0.29-0.82, p = 0.007) (Figure). Conclusions Our data suggest that TAVR is associated with a significant reduction in sPAP. Persistent PH post TAVR seems to be a predictor of higher cumulative mortality post TAVR. Abstract P298 Figure.

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