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This study investigated the incidence, rationales, and associated factors of inappropriate urinary catheter use among hospitalized older patients by gender. A longitudinal study of 321 patients with urinary catheter was conducted. Demographic factors, present health factors, urinary catheter factors, and indications of catheter use were collected. A total of 53.7% of urinary catheter-days were inappropriate. For both men and women, there was no significant difference in the incidence and common rationales of inappropriate use. Women, however, have another associated factor with inappropriate use. More tailored alternatives are needed for women to increase comfort to avoid inappropriate catheter use. [ABSTRACT FROM AUTHOR]

Sample size determination is essential during the planning phases of clinical trials. To calculate the required sample size for paired right-censored data, the structure of the within-paired correlations needs to be pre-specified. In this article, we consider using popular parametric copula models, including the Clayton, Gumbel, or Frank families, to model the distribution of joint survival times. Under each copula model, we derive a sample size formula based on the testing framework for rank-based tests and non-rank-based tests (i.e., logrank test and Kaplan- Meier statistic, respectively). We also investigate how the power or the sample size was affected by the choice of testing methods and copula model under different alternative hypotheses. In addition to this, we examine the impacts of paired-correlations, accrual times, follow-up times, and the loss to follow-up rates on sample size estimation. Finally, two real-world studies are used to illustrate our method and R code is available to the user. [ABSTRACT FROM AUTHOR]

Sample size determination is essential during the planning phases of a study. When the study endpoint is the time to an event, Cox proportional hazard model is the traditional technique to analyze the effects of covariates on survival time. In contrast to the proportional hazard model, the additive hazard (AH) model specifies that the effect of covariates additively increases or decreases the hazard function. The popularity of this model is that it gives a more intuitive interpretation without the proportional hazard assumption. Because there is no literature estimating the required sample size based on the AH model, we provide a flexible formula for calculating the required sample size. The proposed formula incorporates time-independent and time-dependent effects of covariates without complicated mathematical calculations. The performance of the method was evaluated by extensive simulations. Finally, some pilot studies are shown to illustrate the applications. [ABSTRACT FROM PUBLISHER]

Aim The present study aimed to identify the health profiles of older adults by using latent class analysis to investigate health heterogeneity and to determine what factors predicted healthy aging among an oldest-old sample cohort that was followed up for 14 years in Taiwan. Methods Data were drawn from five waves (carried out in 1993, 1996, 1999, 2003 and 2007) of the Taiwan Longitudinal Study on Aging to examine the changes in health heterogeneity in a nationally representative oldest-old cohort of Taiwanese. Overall, data from a total of 11 145 observations of 3155 older adults were considered. The influential factors predicting health changes were analyzed by using a generalized estimating equation. Results The results showed that four health profiles were identified among the aging population observed in the Taiwan Longitudinal Study on Aging. With increasing age, the combined effects of the physical functioning, cognitive and emotional health, and comorbidities of older adults significantly impact their health changes. Apart from health deteriorating with age and sex disparities, educational and economic status, health behaviors, and social participation at the individual level were found to be the robust factors in predicting healthy aging. Conclusions In considering what factors impact healthy aging, we suggest that a person-centered approach would be useful and critical for policy makers to understand the compositions of health profiles and the influencing factors in view of a life-course perspective. Based on the factors identified as influencing healthy aging at the individual level, it is imperative from a policy-making perspective to maximize opportunities for healthy aging. Geriatr Gerontol Int 2017; 17: 697-707. [ABSTRACT FROM AUTHOR]

Determination of an adequate sample size is critical to the design of research ventures. For clustered right-censored data, Manatunga and Chen [Sample size estimation for survival outcomes in cluster-randomized studies with small cluster sizes. Biometrics. 2000;56(2):616–621] proposed a sample size calculation based on considering the bivariate marginal distribution as Clayton copula model. In addition to the Clayton copula, other important family of copulas, such as Gumbel and Frank copulas are also well established in multivariate survival analysis. However, sample size calculation based on these assumptions has not been fully investigated yet. To broaden the scope of Manatunga and Chen [Sample size estimation for survival outcomes in cluster-randomized studies with small cluster sizes. Biometrics. 2000;56(2):616–621]'s research and achieve a more flexible sample size calculation for clustered right-censored data, we extended the work by assuming the marginal distribution as bivariate Gumbel and Frank copulas. We evaluate the performance of the proposed method and investigate the impacts of the accrual times, follow-up times and the within-clustered correlation effect of the study. The proposed method is applied to two real-world studies, and the R code is made available to users. [ABSTRACT FROM PUBLISHER]

The Shewhart-type control chart is traditionally developed under the normality assumption. In practice, however, this assumption may not hold. Because the skew normal distribution represents a broad distribution class and is more flexible than is the normal distribution, we propose two new control charts to monitor process mean and spread for skew normal distributed data. Moreover, to facilitate practical implementation, tables of charting constants are provided. We conducted simulation studies to compare the false alarm rates, and the results show that new proposed charts perform better than others as skewness increases. Finally, an illustrative example is provided. [ABSTRACT FROM PUBLISHER]

Current status data arise naturally from tumorigenicity experiments, epidemiology studies, biomedicine, econometrics and demographic and sociology studies. Moreover, clustered current status data may occur with animals from the same litter in tumorigenicity experiments or with subjects from the same family in epidemiology studies. Because the only information extracted from current status data is whether the survival times are before or after the monitoring or censoring times, the nonparametric maximum likelihood estimator of survival function converges at a rate of n 1∕3 to a complicated limiting distribution. Hence, semiparametric regression models such as the additive hazards model have been extended for independent current status data to derive the test statistics, whose distributions converge at a rate of n 1∕2, for testing the regression parameters. However, a straightforward application of these statistical methods to clustered current status data is not appropriate because intracluster correlation needs to be taken into account. Therefore, this paper proposes two estimating functions for estimating the parameters in the additive hazards model for clustered current status data. The comparative results from simulation studies are presented, and the application of the proposed estimating functions to one real data set is illustrated. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Clustered right-censored data often arise from tumorigenicity experiments and clinical trials. For testing the equality of two survival functions, Jung and Jeong extended weighted logrank (WLR) tests to two independent samples of clustered right-censored data, while the weighted Kaplan-Meier (WKM) test can be derived from the work of O'Gorman and Akritas. The weight functions in both classes of tests (WLR and WKM) can be selected to be more sensitive to detect a certain alternative; however, since the exact alternative is unknown, it is difficult to specify the selected weights in advance. Since WLR is rank-based, it is not sensitive to the magnitude of the difference in survival times. Although WKM is constructed to be more sensitive to the magnitude of the difference in survival times, it is not sensitive to late hazard differences. Therefore, in order to combine the advantages of these two classes of tests, this paper developed a class of versatile tests based on simultaneously using WLR and WKM for two independent samples of clustered right-censored data. The comparative results from a simulation study are presented and the implementation of the versatile tests to two real data sets is illustrated. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Indoor CO 2 concentration is an important metric of indoor air quality (IAQ). The dynamic temporal pattern of CO 2 levels in intensive care units (ICUs), where healthcare providers experience high cognitive load and occupant numbers are frequently changing, has not been comprehensively characterized., Objective: We attempted to describe the dynamic change in CO 2 levels in the ICU using an Internet of Things-based (IoT-based) monitoring system. Specifically, given that the COVID-19 pandemic makes hospital visitation restrictions necessary worldwide, this study aimed to appraise the impact of visitation restrictions on CO 2 levels in the ICU., Methods: Since February 2020, an IoT-based intelligent indoor environment monitoring system has been implemented in a 24-bed university hospital ICU, which is symmetrically divided into areas A and B. One sensor was placed at the workstation of each area for continuous monitoring. The data of CO 2 and other pollutants (e.g., PM2.5) measured under standard and restricted visitation policies during the COVID-19 pandemic were retrieved for analysis. Additionally, the CO 2 levels were compared between workdays and non-working days and between areas A and B., Results: The median CO 2 level (interquartile range [IQR]) was 616 (524-682) ppm, and only 979 (0.34%) data points obtained in area A during standard visitation were ≥ 1,000 ppm. The CO 2 concentrations were significantly lower during restricted visitation (median [IQR]: 576 [556-596] ppm) than during standard visitation (628 [602-663] ppm; p  < 0.001). The PM2.5 concentrations were significantly lower during restricted visitation (median [IQR]: 1 [0-1] μg/m 3 ) than during standard visitation (2 [1-3] μg/m 3 ; p  < 0.001). The daily CO 2 and PM2.5 levels were relatively low at night and elevated as the occupant number increased during clinical handover and visitation. The CO 2 concentrations were significantly higher in area A (median [IQR]: 681 [653-712] ppm) than in area B (524 [504-547] ppm; p  < 0.001). The CO 2 concentrations were significantly lower on non-working days (median [IQR]: 606 [587-671] ppm) than on workdays (583 [573-600] ppm; p  < 0.001)., Conclusion: Our study suggests that visitation restrictions during the COVID-19 pandemic may affect CO 2 levels in the ICU. Implantation of the IoT-based IAQ sensing network system may facilitate the monitoring of indoor CO 2 levels., Competing Interests: Z-YW and H-CC were employed by UniSmart Technology Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Chou, Wang, Chang, Liu, Su, Huang, Yang and Lai.)

Background: The optimal alternative treatment strategy to coronary artery bypass graft surgery (CABG) for in-stent restenosis (ISR) in left main (LM) coronary artery disease remains uncertain., Methods: We retrospectively screened all intervention reports from an intervention database and extracted those mentioning an LM stent. We then manually confirmed reports involving LM ISR and divided them into two groups, those in which the patient received a new drug-eluting stent (new-DES) strategy, and those in which the patient received a drug-coated balloon (DCB) only. A composite endpoint of major adverse cardiovascular events (MACEs) and each individual endpoint were compared. We also performed a brief analysis of similar designed studies., Results: Between the new-DES (n = 40) and DCB-only (n = 22) groups, during median respective follow-up times of 581.5 and 642.5 days, no significant statistical differences were detected in MACEs (50.0% vs. 50.0%, p = 0.974), cardiovascular death (27.5% vs. 13.6%, p = 0.214), nonfatal myocardial infarction (30.0% vs. 31.8%, p = 0.835), or target lesion revascularization (35.0% vs. 45.5%, p = 0.542). We analyzed four similar studies and found comparable MACE findings (odds ratio: 0.85, 95% CI: 0.44-1.67)., Conclusions: Our findings support both DCB angioplasty and repeat DES implantation for LMISR lesions in patients who were clinically judged to be unsuitable for CABG; the treatments achieved comparable clinical results in terms of MACEs in the medium term.

Background: Hydroxychloroquine is used as an antimalarial and immunomodulator, however it can induce QT prolongation that could potentially lead to fatal arrhythmia. We investigated changes in QT interval in long-term hydroxychloroquine users, and identified possible risk factors associated with significant QTc prolongation., Methods: We retrospectively enrolled 3603 patients who received long-term hydroxychloroquine treatment from 2009 to 2019, of whom 167 had electrocardiography (ECG) results before and during hydroxychloroquine therapy. Baseline characteristics, laboratory data, comorbidities, concurrent medications, and related clinical outcomes were reviewed., Results: Overall, 225 patients (6.2%) died within the study period, with 50 patients (1.4%) continuously receiving hydroxychloroquine treatment until death. Three patients had fatal ventricular arrhythmia. No significant change in corrected QT interval (QTc) was noted before and during hydroxychloroquine treatment (451.1 ± 39.9 ms vs. 456.0 ± 37.3 ms, P = 0.140) in the ECG cohort. Multivariable logistic regression showed that diabetes mellitus [odds ratio (OR): 9.55, 95% confidence interval (CI): 2.02-45.22; P = 0.005] and use of additional QT-prolonging drugs (OR: 2.89, 95% CI: 1.40-5.94; P = 0.004) were independent risk factors for significant QTc prolongation. Multiple linear regression, with the number of QT-prolonging drugs and comorbidities including diabetes mellitus, hypertension, and atrial fibrillation as explanatory variables, predicted QTc response (adjusted R 2 = 0.385) in the long-term hydroxychloroquine users., Conclusions: In the long-term users of hydroxychloroquine, those with diabetes mellitus and concurrent use of additional QT-prolonging drugs were at a higher risk of significant QTc prolongation. Baseline QTc interval, concurrent medications, and comorbidities predicted QTc response.

In long-term clinical studies, recurrent event data are frequently collected to contrast the efficacy of two different treatments. However, the recurrent event process can be stopped by a terminal event, such as death. For analyzing recurrent event and terminal event data, joint frailty modeling has recently received considerable attention because it makes it possible to study the joint evolution over time of both recurrent and terminal event processes and gives consistent and efficient parameters. For a two-arm clinical trial design based on these data sets, there has been limited research on investigating the balanced design, let alone adaptive treatment allocation. Although equal sample size allocation obtained for both treatments is intuitively first adopted in a trial design, if one treatment is expected to be superior, it may be desirable to allocate more subjects to the effective treatment. In this article, we calculate the required sample size based on restricted randomization and then propose a target response-adaptive randomization procedure for recurrent and terminal event outcomes based on the joint frailty model. A randomization procedure, the doubly adaptive biased coin design that targets some optimal allocations, is implemented. The proposed adaptive treatment allocation schemes have been shown to be capable of reducing the number of trial participants who receive inferior treatment while simultaneously reaching an optimal target, as well as retaining a comparable test power as compared to a restricted randomization design. Finally, two clinical studies, the COAPT trial and the A-HeFT trial, are used to illustrate the advantages of adopting the proposed procedure., (© 2021 John Wiley & Sons Ltd.)

Purpose: A slouching posture during smartphone usage increases gravitational loadings on the cervical spine, which may lead to neck pain and degeneration. The objective of the present study was to investigate the head, neck and trunk angles in different smartphone-usage postures, as well as the posture-correction effects and comfort scores of three neck collars., Methods: This was a prospective cohort study in which 41 healthy young subjects aged 18-25 were recruited. The head, neck and trunk angles were measured in all participants during a neutral position and three smartphone-using postures, including sitting with and without back support and standing. The postural correction and comfort scores of three collars (Aspen Vista, Sport-aid and our customized 3D printed collars) were compared., Results: Smartphone use increased the head and neck flexion angles in all postures, and sitting without back support showed the greatest head and neck flexion angles. The posture-correcting effect of the customized collar was better than the Aspen Vista and Sport-aid collars. In addition, the customized collar was more comfortable to wear than the other two collars in most contact areas., Conclusion: Smartphone use increased both the head and neck flexion in different postures, and the proposed customized 3D-printed cervical collar significantly reduced the head and neck angles. These slides can be retrieved under Electronic Supplementary Material.

Proteins involved in tumor cell migration can potentially serve as markers of invasive disease. Activated Leukocyte Cell Adhesion Molecule (ALCAM) promotes adhesion, while shedding of its extracellular domain is associated with migration. We hypothesized that shed ALCAM in biofluids could be predictive of progressive disease. ALCAM expression in tumor (n = 198) and shedding in biofluids (n = 120) were measured in two separate VUMC bladder cancer cystectomy cohorts by immunofluorescence and enzyme-linked immunosorbent assay, respectively. The primary outcome measure was accuracy of predicting 3-year overall survival (OS) with shed ALCAM compared to standard clinical indicators alone, assessed by multivariable Cox regression and concordance-indices. Validation was performed by internal bootstrap, a cohort from a second institution (n = 64), and treatment of missing data with multiple-imputation. While ALCAM mRNA expression was unchanged, histological detection of ALCAM decreased with increasing stage (P = 0.004). Importantly, urine ALCAM was elevated 17.0-fold (P < 0.0001) above non-cancer controls, correlated positively with tumor stage (P = 0.018), was an independent predictor of OS after adjusting for age, tumor stage, lymph-node status, and hematuria (HR, 1.46; 95% CI, 1.03-2.06; P = 0.002), and improved prediction of OS by 3.3% (concordance-index, 78.5% vs. 75.2%). Urine ALCAM remained an independent predictor of OS after accounting for treatment with Bacillus Calmette-Guerin, carcinoma in situ, lymph-node dissection, lymphovascular invasion, urine creatinine, and adjuvant chemotherapy (HR, 1.10; 95% CI, 1.02-1.19; P = 0.011). In conclusion, shed ALCAM may be a novel prognostic biomarker in bladder cancer, although prospective validation studies are warranted. These findings demonstrate that markers reporting on cell motility can act as prognostic indicators.

Background & Aims: We investigated the rate of relapse of hepatitis B virus (HBV) infection after entecavir therapy for chronic hepatitis B and the association between level of hepatitis B surface antigen (HBsAg) and relapse., Methods: In a retrospective study, we analyzed data from 252 patients with chronic HBV infection who were treated with entecavir and met the Asian Pacific Association for the Study of the Liver treatment stopping rules (mean time, 164 ± 45 weeks) from January 2007 through June 2011 in Taiwan. Eighty-three were hepatitis B e antigen (HBeAg)-positive, and 169 were HBeAg-negative. Patients had regular post-treatment follow-up examinations for at least 12 months. Virologic relapse was defined on the basis of serum HBV DNA >2000 IU/mL after entecavir therapy. Clinical relapse was defined as a level of alanine aminotransferase > 2-fold the upper limit of normal and HBV DNA > 2000 IU/mL., Results: Two years after therapy ended, 42% of HBeAg-positive patients had a virologic relapse, and 37.6% had a clinical relapse; 3 years after therapy ended, these rates were 64.3% and 51.6% for HBeAg-negative patients, respectively. On the basis of Cox regression analysis, factors independently associated with virologic and clinical relapse included old age, HBV genotype C, and higher baseline levels of HBsAg for HBeAg-positive patients and old age and higher end-of-treatment levels of HBsAg for HBeAg-negative patients. In HBeAg-positive patients, risk of HBV relapse increased with age ≥ 40 years and HBsAg level ≥ 1000 IU/mL at baseline (P < .001). In HBeAg-negative patients, the combination of age (< 55 years) and HBsAg level (< 150 IU/mL) at the end of treatment was associated with a lower rate of virologic relapse (4.5% of HBeAg-negative patients had viral relapse at year 3). The decrease in level of HBsAg from month 12 of treatment until the end of treatment was greater in patients who did lose HBsAg after entecavir therapy compared with those who did not., Conclusions: The combination of age and level of HBsAg is associated with relapse of HBV infection after treatment with entecavir. HBsAg levels might be used to guide the timing of cessation of entecavir treatment in patients with chronic HBV infection., (Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background: Increasing evidence indicates that proteotoxicity plays a pathophysiologic role in experimental and human cardiomyopathy. In organ-specific amyloidoses, soluble protein oligomers are the primary cytotoxic species in the process of protein aggregation. While isolated atrial amyloidosis can develop with aging, the presence of preamyloid oligomers (PAOs) in atrial tissue has not been previously investigated., Methods and Results: Atrial samples were collected during elective cardiac surgery in patients without a history of atrial arrhythmias, congestive heart failure, cardiomyopathy, or amyloidosis. Immunohistochemistry was performed for PAOs using a conformation-specific antibody, as well as for candidate proteins identified previously in isolated atrial amyloidosis. Using a myocardium-specific marker, the fraction of myocardium colocalizing with PAOs (PAO burden) was quantified (green/red ratio). Atrial samples were obtained from 92 patients, with a mean age of 61.7±13.8 years. Most patients (62%) were male, 23% had diabetes, 72% had hypertension, and 42% had coronary artery disease. A majority (n=62) underwent aortic valve replacement, with fewer undergoing coronary artery bypass grafting (n=34) or mitral valve replacement/repair (n=24). Immunostaining detected intracellular PAOs in a majority of atrial samples, with a heterogeneous distribution throughout the myocardium. Mean green/red ratio value for the samples was 0.11±0.1 (range 0.03 to 0.77), with a value ≥0.05 in 74 patients. Atrial natriuretic peptide colocalized with PAOs in myocardium, whereas transthyretin was located in the interstitium. Adjusting for multiple covariates, PAO burden was independently associated with the presence of hypertension., Conclusion: PAOs are frequently detected in human atrium, where their presence is associated with clinical hypertension., (© 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Abnormalities in atrial myocardium increase the likelihood of arrhythmias, including atrial fibrillation (AF). The deposition of misfolded protein, or amyloidosis, plays an important role in the pathophysiology of many diseases, including human cardiomyopathies. We have shown that genes implicated in amyloidosis are activated in a cellular model of AF, with the development of preamyloid oligomers (PAOs). PAOs are intermediates in the formation of amyloid fibrils, and they are now recognized to be the cytotoxic species during amyloidosis. To investigate the presence of PAOs in human atrium, we developed a microscopic imaging-based protocol to enable robust and reproducible quantitative analysis of PAO burden in atrial samples harvested at the time of elective cardiac surgery. Using PAO- and myocardial-specific antibodies, we found that PAO distribution was typically heterogeneous within a myocardial sample. Rigorous imaging and analysis protocols were developed to quantify the relative area of myocardium containing PAOs, termed the Green/Red ratio (G/R), for a given sample. Using these methods, reproducible G/R values were obtained when different sections of a sample were independently processed, imaged, and analyzed by different investigators. This robust technique will enable studies to investigate the role of this novel structural abnormality in the pathophysiology of and arrhythmia generation in human atrial tissue., (© The Author(s) 2014.)

RNAseq technology is replacing microarray technology as the tool of choice for gene expression profiling. While providing much richer data than microarray, analysis of RNAseq data has been much more challenging. Among the many difficulties of RNAseq analysis, correctly adjusting for batch effect is a pivotal one for large-scale RNAseq based studies. The batch effect of RNAseq data is most obvious in microRNA (miRNA) sequencing studies. Using real miRNA sequencing (miRNAseq) data, we evaluated several batch removal techniques and discussed their effectiveness. We illustrate that by adjusting for batch effect, more reliable differentially expressed genes can be identified. Our study on batch effect in miRNAseq data can serve as a guideline for future miRNAseq studies that might contain batch effect.

Sample size determination is essential to planning clinical trials. Jung (2008) established a sample size calculation formula for paired right-censored data based on the logrank test, which has been well-studied for comparing independent survival outcomes. An alternative to rank-based methods for independent right-censored data, advocated by Pepe and Fleming (1989), tests for differences between integrated weighted Kaplan-Meier estimates and is more sensitive to the magnitude of difference in survival times between groups. In this paper, we employ the concept of the Pepe-Fleming method to determine an adequate sample size by calculating differences between Kaplan-Meier estimators considering pair-wise correlation. We specify a positive stable frailty model for the joint distribution of paired survival times. We evaluate the performance of the proposed method by simulation studies and investigate the impacts of the accrual times, follow-up times, loss to follow-up rate, and sensitivity of power under misspecification of the model. The results show that ignoring the pair-wise correlation results in overestimating the required sample size. Furthermore, the proposed method is applied to two real-world studies, and the R code for sample size calculation is made available to users.