Relative effectiveness of a heterologous booster dose with adenovirus type 5 vectored COVID-19 vaccine versus three doses of inactivated COVID-19 vaccine in adults during a nationwide outbreak of omicron predominance, in China: a retrospective, individually matched cohort-control study

Effectiveness of heterologous booster regimes with ad5 vectored COVID-19 vaccine in a large, diverse population during the national-scale outbreak of SARS-CoV-2 omicron predominance in China has not been reported, yet. We conducted a large-scale cohort-control study in six provinces in China, and did a retrospective survey on the COVID-19 attack risk during this outbreak. Participant aged ≥18 years in five previous trials who were primed with 1 to 3 doses of ICV received heterologous booster with either intramuscular or orally inhaled ad5 vectored COVID-19 vaccine were included in the heterologous-trial cohort. We performed propensity score-matching at a ratio of 1:4 to match participants in the heterologous-trial cohort individually with the community individuals who received three-dose of ICV as a control (ICV-community cohort). From February 4 to April 10, 2023, 41504 (74.5%) of 55710 individuals completed the survey. The median time since the most recent vaccination to the onset of the symptoms of COVID-19 was 303.0 days (IQR 293.0-322.0). The attack rate of COVID-19 in the heterologous-trial cohort was 55.8%, while that in the ICV-community cohort was 64.6%, resulting in a relative effectiveness of 13.7% (95% CI 11.9 to 15.3). In addition, a higher relative effectiveness against COVID-19 associated outpatient visits, and admission to hospital was demonstrated, which was 25.1% (95% CI 18.9 to 30.9), and 48.9% (95% CI 27.0 to 64.2), respectively. The heterologous booster with ad5 vectored COVID-19 vaccine still offered some additional protection in preventing COVID-19 breakthrough infection versus homologous three-dose regimen with ICV, 10 months after vaccination.

Causal interpretation of the hazard ratio in randomized clinical trials

BACKGROUND

Although the hazard ratio has no straightforward causal interpretation, clinical trialists commonly use it as a measure of treatment effect.

METHODS

We review the definition and examples of causal estimands. We discuss the causal interpretation of the hazard ratio from a two-arm randomized clinical trial, and the implications of proportional hazards assumptions in the context of potential outcomes. We illustrate the application of these concepts in a synthetic model and in a model of the time-varying effects of COVID-19 vaccination.

RESULTS

We define causal estimands as having either an individual-level or population-level interpretation. Difference-in-expectation estimands are both individual-level and population-level estimands, whereas without strong untestable assumptions the causal rate ratio and hazard ratio have only population-level interpretations. We caution users against making an incorrect individual-level interpretation, emphasizing that in general a hazard ratio does not on average change each individual's hazard by a factor. We discuss a potentially valid interpretation of the constant hazard ratio as a population-level causal effect under the proportional hazards assumption.

CONCLUSION

We conclude that the population-level hazard ratio remains a useful estimand, but one must interpret it with appropriate attention to the underlying causal model. This is especially important for interpreting hazard ratios over time.

Risk of cardiovascular disorders in hidradenitis suppurativa patients: a large-scale, propensity-matched global retrospective cohort study

BACKGROUND

Patients with hidradenitis suppurativa (HS) often suffer from comorbid diabetes, metabolic syndrome, and hyperlipidemia and, therefore, are susceptible to the development of cardiovascular diseases (CVDs). Moreover, systemic inflammation plays a vital role in the development of atherosclerosis. The creation of atherosclerotic plaque is characterized by endothelial dysfunction driven by elevated concentrations of interleukin (IL)-1, IL-6, and IL-18 among others, as well as tumor necrosis factor (TNF) alpha.

METHODS

This study aimed to assess the risk of HS patients developing CVDs. We performed a large-scale, propensity-matched global retrospective cohort study analyzing the risk of development of CVDs in patients suffering from HS. The analysis included 144,100 HS patients with 144,100 healthy controls (HC). The cohorts were matched regarding demographics and history of diseases relevant to CVDs, e.g., diabetes, obesity, and nicotine dependence. A total of 90 cardiovascular disorders were identified. The identification of cardiovascular disorders was based on ≥1% appearance of the event, based on absolute numbers, in both cohorts.

RESULTS

Before the matching, HS patients displayed a higher frequency in excess weight or obesity (25 vs. 14.4%, respectively), nicotine dependence, and diabetes mellitus, but lower odds of primary hypertension in comparison to healthy controls. A total of 47 CVDs are associated with an increased risk of onset in HS patients. Although the highest hazard ratio (HR; 2.1; 95% CI: 1.95-2.269) was found for unspecified heart failure, the HS cohort was exceptionally predisposed to developing myocardial infarction (HR: 2.06; 95% CI: 1.88-2.27) and an acute embolism and deep vein thrombosis of the lower extremity (HR: 1.93; 95% CI: 1.74-2.14).

CONCLUSIONS

This is the most extensive study on the association of HS with CVDs. We demonstrated that HS patients are at significantly greater risk of developing various CVDs compared to matched controls, with heart failure being the most common one.

Evaluating treatment efficacy in hospitalized COVID-19 patients, with applications to Adaptive COVID-19 Treatment Trials

BACKGROUND

The current endpoints for therapeutic trials of hospitalized COVID-19 patients capture only part of the clinical course of a patient and have limited statistical power and robustness.

METHODS

We specify proportional odds models for repeated measures of clinical status, with a common odds ratio of lower severity over time. We also specify the proportional hazards model for time to each level of improvement or deterioration of clinical status, with a common hazard ratio for overall treatment benefit. We apply these methods to Adaptive COVID-19 Treatment Trials.

RESULTS

For remdesivir versus placebo, the common odds ratio was 1.48 (95% confidence interval (CI) = 1.23-1.79; p < 0.001), and the common hazard ratio was 1.27 (95% CI = 1.09-1.47; p = 0.002). For baricitinib plus remdesivir versus remdesivir alone, the common odds ratio was 1.32 (95% CI = 1.10-1.57; p = 0.002), and the common hazard ratio was 1.30 (95% CI = 1.13-1.49; p < 0.001). For interferon beta-1a plus remdesivir versus remdesivir alone, the common odds ratio was 0.95 (95% CI = 0.79-1.14; p = 0.56), and the common hazard ratio was 0.98 (95% CI = 0.85-1.12; p = 0.74).

CONCLUSIONS

The proposed methods comprehensively characterize the treatment effects on the entire clinical course of a hospitalized COVID-19 patient.

Association between metabolic syndrome severity score and cardiovascular disease: results from a longitudinal cohort study on Chinese adults

Objective

This study aimed to quantify the severity of metabolic syndrome(MetS) and investigate its association with cardiovascular disease(CVD) risk on Chinese adults.

Methods

13,500 participants from the Zhejiang Adult Chronic Disease Study were followed up between 2010 and 2021. A continuous MetS severity score derived from the five components of MetS was used to quantify MetS severity, and the association between MetS severity and the risk of incident CVD was assessed using Cox proportional hazard and restricted cubic spline regression.

Results

Both the presence and severity of MetS were strongly associated with CVD risk. MetS was related to an increased risk of CVD (hazard ratio(HR):1.700, 95% confidence interval(CI): 1.380-2.094). Compared with the hazard ratio for CVD in the lowest quartile of the MetS severity score, that in the second, third, and highest quartiles were 1.812 (1.329-2.470), 1.746 (1.265-2.410), and 2.817 (2.015-3.938), respectively. A linear and positive dose-response relationship was observed between the MetS severity and CVD risk (P for non-linearity = 0.437). Similar results were found in various sensitivity analyses.

Conclusion

The MetS severity score was significantly associated with CVD risk. Assessing MetS severity and further ensuring intervention measures according to the different severities of MetS may be more useful in preventing CVD.

Micro-RNAs With Prognostic Significance in Gallbladder Cancer: A Systematic Review and Meta-Analysis

Gallbladder cancer (GBC) stands out as one of the most widespread malignancies impacting the biliary tract globally. Despite increasing interest, to the best of our knowledge, no meta-analysis has been undertaken to amalgamate the existing data concerning the prognostic significance of micro-RNAs (miRNAs) in GBC in comparison to studies on miRNAs in other cancers. Hence, this systematic review and meta-analysis aimed at determining the prognostic significance of miRNAs in GBC patients. Comprehensive literature searches were conducted across PubMed, Cochrane Library, Ovid, Scopus, and Science Direct databases. Studies that evaluated the association between miRNAs and overall survival in GBC patients were included. Random-effect meta-analysis was employed to pool hazard ratios (HRs) and their 95% confidence intervals (CIs) across studies. A total of 15 studies, encompassing 16 miRs, were included for our analysis. The pooled analysis revealed that a high expression of miR-204, miR-7-2-3p, miR-29c-3p, miR-125b, miR-20a, miR-139-5p, miR-141, miR-92b-3p, miR-335, and miR-372 was significantly associated with poor prognosis and increased risk (HR>1 and the upper bound of the 95% CI>1). Additionally, these miRNAs were associated with the overall survival (HR = 1.56, 95% CI = 0.91-2.20, I2 = 91.82%). Significant heterogeneity was observed and could be attributed to the limited number of studies available on the GBC and significant reliance on quantitative real-time PCR for the detection of miRNAs. In conclusion, specific miRNAs exhibit prognostic significance in GBC, with potential implications for patient stratification and targeted therapeutic interventions. However, due to the heterogeneity among studies, these findings should be interpreted cautiously and validated in larger cohorts.

Is inadequate risk stratification diluting hazard ratio estimates in randomized clinical trials?

In randomized clinical trials, analyses of time-to-event data without risk stratification, or with stratification based on pre-selected factors revealed at the end of the trial to be at most weakly associated with risk, are quite common. We caution that such analyses are likely delivering hazard ratio estimates that unwittingly dilute the evidence of benefit for the test relative to the control treatment. To make our case, first, we use a hypothetical scenario to contrast risk-unstratified and risk-stratified hazard ratios. Thereafter, we draw attention to the previously published 5-step stratified testing and amalgamation routine (5-STAR) approach in which a pre-specified treatment-blinded algorithm is applied to survival times from the trial to partition patients into well-separated risk strata using baseline covariates determined to be jointly strongly prognostic for event risk. After treatment unblinding, a treatment comparison is done within each risk stratum and stratum-level results are averaged for overall inference. For illustration, we use 5-STAR to reanalyze data for the primary and key secondary time-to-event endpoints from three published cardiovascular outcomes trials. The results show that the 5-STAR estimate is typically smaller (i.e. more in favor of the test treatment) than the originally reported (traditional) estimate. This is not surprising because 5-STAR mitigates the presumed dilution bias in the traditional hazard ratio estimate caused by no or inadequate risk stratification, as evidenced by two detailed examples. Pre-selection of stratification factors at the trial design stage to achieve adequate risk stratification for the analysis will often be challenging. In such settings, an objective risk stratification approach such as 5-STAR, which is partly aligned with guidance from the US Food and Drug Administration on covariate-adjustment in clinical trials, is worthy of consideration.

Higher Age is Associated with Lower Likelihood of Conversion to Surgery after Primary Nonoperative Treatment for Osteochondral Lesions of the Talus

INTRODUCTION

The first line of treatment for osteochondral lesions of the talus (OLT) is nonoperative. To date, there is limited evidence on risk factors that may influence conversion to surgery after primary nonoperative treatment for symptomatic OLTs. The aim of this study was therefore to identify risk factors for conversion to surgery after initial nonoperative treatment of OLTs.

METHODS

For this cohort study, patients with a primary OLT who were nonoperatively treated for at least 6 months between 1990 and 2020 were included. Univariable Cox regression analysis, resulting in hazard ratios (HRs), on the primary outcome (i.e. conversion to surgery after initial nonoperative treatment) was performed for potential risk factors. The following risk factors were analyzed: gender, age, body mass index (BMI), numeric rating scale (NRS), lesion size (depth, sagittal length, coronal length, volume, surface), lesion morphology (presence of fragments and presence of cysts), lesion location (medial/central/lateral), congruency of the ankle joint and trauma in history. Data imputation was conducted according to the multiple data principle with pooling.

RESULTS

Forty-two patients with primary OLTs were included in this study: 23 (55%) males and 19 (45%) females with a mean age of 39.1 (SD: 14.2). The median overall follow-up time was 66 months (range: 7-188). Around 23% of the patients had a conversion to surgery at the median observation time. The Kaplan-Meier analysis revealed a survival rate of 93% (95% confidence interval [CI]:84-100), 90% (95% CI: 81-99), and 77% (95% CI: 63-91) at 1, 2, and 5 years after the initiation of treatment, respectively. After performing the COX regression analysis, age was the sole risk factor significantly associated with conversion to surgery with an HR of 0.93 (95% CI: 0.87-0.99). The different HRs for all other risk factors were as follows: gender: 0.33 (95% CI: 0.08-1.34), BMI: 0.87 (95% CI 0.76-1.01), depth: 0.97 (95% CI: 0.79-1.18), coronal length: 1.19 (95% CI: 0.97-1.44), sagittal length: 0.98 (95% CI: 0.87-1.12), surface area: 1.17 (95% CI: 0.41-3.31), volume: 0.96 (95% CI: 0.24-3.91), presence of fragments: 4.17 (95% CI: 0.84-20.61).

CONCLUSION

For primary OLTs, 77% of the patients were successfully treated nonoperatively at a median follow-up of 66 months without the need for a surgical intervention. Survival rates of 93%, 90%, and 77% were found at 1, 2, and 5 years after the initiation of treatment, respectively. We found that a higher age at the moment of diagnosis was significantly associated with a lower likelihood of conversion to surgery with a 7% decrease of likelihood each year the patient is older at the moment of diagnosis. The findings of this study are clinically relevant as it ameliorates the quality of the shared decision-making process between the patient and the treating team as we can advise OLT patients at a higher age with tolerable symptomatology that there is a relatively lower risk of conversion to surgery.

Effects of simplified group housing on behavior, growth performance and health of preweaned dairy calves on a California dairy

Most US dairy calves are raised in individual hutches (IH) for biocontainment purposes and to facilitate monitoring and handling of calves. However, individual hutches typically restrict calves' activity and social interactions. Previous studies showed that group housing (GH) is beneficial to calf welfare and is associated with social benefits. The adoption of group housing (GH) on dairies is hindered by several concerns, with the primary concern being the potential for increased transmission of diseases due to heightened calf-to-calf contact. In light of this, our study aimed to compare the behavior, health, and growth outcomes of calves housed in groups of 3 to individually housed (IH) calves during the preweaning period. A total of 42 Holstein heifer calves on a commercial dairy in Northern California were enrolled in groups of 3 to different housing treatments; IH (n = 21) or GH (n = 21) between July and October 2020. Each treatment was composed of 7 groups of 3 calves each. Calves in the GH treatment were housed in groups of 3 from 6 to 10 d until 70 d of age. Individual pens consisted of one polyethylene hutch with a 1.5 m x 1.2 m outside exercise area. Group pens were constructed by assembling 3 polyethylene hutches with a 1.5 m x 3.6 m outside exercise area of wire panel fencing. Calves were weighed and measured for height at birth and weaning. Diarrhea and bovine respiratory disease (BRD) scores were recorded daily throughout the preweaning period. Cumulative incidence and hazard ratios were estimated for BRD and diarrhea for GH and IH. A Mixed model with pen as a random effect was specified to evaluate the effect of treatment. Group-housed calves gained 0.64 ± 0.02 kg/d while IH calves gained 0.65 ± 0.02 kg/d (P = 0.40). Similarly, there was no evidence for treatment differences in withers height gain in GH calves (0.22 ± 0.01cm/d) compared with IH calves (0.21 ± 0.01 cm/d) (P = 0.14). The cumulative incidence of BRD based on California scoring system in GH calves was 75 ± 9.68 compared with 66.66 ± 10.28% in IH calves (P = 0.73). Group-housed calves had a BRD hazard of 1.14 times that of IH calves (95% CI: 1.21-2.40; P = 0.74). The cumulative incidence of diarrhea (fecal score 3) in GH calves was 100% in comparison to 95.20 ± 4.66% in IH calves (P = 0.99). The mean proportion of scan observations of calves feeding on concentrates was significantly higher in GH (0.145 ± 0.004 per h) compared with IH calves (0.076 ± 0.003 per h) during the preweaning period (P < 0.001). The study results provide evidence that this simplified group housing system provides benefits of GH without detrimental short-term impacts during the preweaning period on calf growth and health.

Estimating drug concentration-response relationships by applying causal inference methods for continuous point exposures and time-to-event outcomes

In clinical development, it is useful to characterize the causal relationship between individual drug concentrations and clinical outcomes in large phase III trials of new therapeutic agents because it can provide insights on whether increasing the currently administered drug dose may lead to better outcomes. However, estimating causal effects of drug concentration is complicated by the fact that drug concentration is a continuous measure and it is usually influenced by patient-level prognostic characteristics such as body weight and sex. In this article, we compare two approaches to estimate causal effects of continuous point exposures on time-to-event outcomes: (a) outcome regression (OR) and (b) weighting. In particular, we make the first direct comparison of the balancing weights, inverse probability weighting and OR methods for estimating the effects of continuous exposures on time-to-event outcomes in simulations and demonstrate that these methods can exhibit markedly different behaviours that subsequently lead to a change in the conclusions. To improve weighted exposure effect estimators, we also propose a new simple-to-apply diagnostic to detect when such estimators might be subject to severe bias, and demonstrate its effectiveness in simulations. Finally, we apply these methods to an example of multiple sclerosis drug development by providing causal effect estimates of average ocrelizumab concentrations on time-to-event disability progression outcomes.

A comparison of different population-level summary measures for randomised trials with time-to-event outcomes, with a focus on non-inferiority trials

BACKGROUND

The population-level summary measure is a key component of the estimand for clinical trials with time-to-event outcomes. This is particularly the case for non-inferiority trials, because different summary measures imply different null hypotheses. Most trials are designed using the hazard ratio as summary measure, but recent studies suggested that the difference in restricted mean survival time might be more powerful, at least in certain situations. In a recent letter, we conjectured that differences between summary measures can be explained using the concept of the non-inferiority frontier and that for a fair simulation comparison of summary measures, the same analysis methods, making the same assumptions, should be used to estimate different summary measures. The aim of this article is to make such a comparison between three commonly used summary measures: hazard ratio, difference in restricted mean survival time and difference in survival at a fixed time point. In addition, we aim to investigate the impact of using an analysis method that assumes proportional hazards on the operating characteristics of a trial designed with any of the three summary measures.

METHODS

We conduct a simulation study in the proportional hazards setting. We estimate difference in restricted mean survival time and difference in survival non-parametrically, without assuming proportional hazards. We also estimate all three measures parametrically, using flexible survival regression, under the proportional hazards assumption.

RESULTS

Comparing the hazard ratio assuming proportional hazards with the other summary measures not assuming proportional hazards, relative performance varies substantially depending on the specific scenario. Fixing the summary measure, assuming proportional hazards always leads to substantial power gains compared to using non-parametric methods. Fixing the modelling approach to flexible parametric regression assuming proportional hazards, difference in restricted mean survival time is most often the most powerful summary measure among those considered.

CONCLUSION

When the hazards are likely to be approximately proportional, reflecting this in the analysis can lead to large gains in power for difference in restricted mean survival time and difference in survival. The choice of summary measure for a non-inferiority trial with time-to-event outcomes should be made on clinical grounds; when any of the three summary measures discussed here is equally justifiable, difference in restricted mean survival time is most often associated with the most powerful test, on the condition that it is estimated under proportional hazards.

Influencing factors of death in patients with MDR-TB based on Bayesian Cox regression model

OBJECTIVES

Multidrug-resistant tuberculosis (MDR-TB) has a high mortality and is always one of the major challenges in global TB prevention and control. Analyzing the factors that may impact the adverse outcomes of MDR-TB patients is helpful for improving the systematic management and optimizing the treatment strategies for MDR-TB patients. For follow-up data, the Cox proportional hazards regression model is an important multifactor analysis method. However, the method has significant limitations in its application, such as the fact that it is difficult to deal with the impacts of small sample sizes and other practical issues on the model. Therefore, Bayesian and conventional Cox regression models were both used in this study to analyze the influencing factors of death in MDR-TB patients during the anti-TB therapy, and compare the differences between these 2 methods in their application.

METHODS

Data were obtained from 388 MDR-TB patients treated at Lanzhou Pulmonary Hospital from November 1, 2017 to March 31, 2021. Survival analysis was employed to analyze the death of MDR-TB patients during the therapy and its influencing factors. Conventional and Bayesian Cox regression models were established to estimate the hazard ratios (HR) and their 95% confidence interval (95% CI) for the factors affecting the death of MDR-TB patients. The reliability of parameter estimation in these 2 models was assessed by comparing the parameter standard deviation and 95% CI of each variable. The smaller parameter standard deviation and narrower 95% CI range indicated the more reliable parameter estimation.

RESULTS

The median survival time (1st quartile, 3rd quartile) of the 388 MDR-TB patients included in the study was 10.18 (4.26, 18.13) months, with the longest survival time of 31.90 months. Among these patients, a total of 12 individuals died of MDR-TB and the mortality was 3.1%. The median survival time (1st quartile, 3rd quartile) for the deceased patients was 4.78(2.63, 6.93) months. The majority of deceased patients, accounting for 50%, experienced death within the first 5 months of anti-TB therapy, with the last mortality case occurring within the 13th month of therapy. The results of the conventional Cox regression model showed that the risk of death in MDR-TB patients with comorbidities was approximately 6.96 times higher than that of patients without complications (HR=6.96, 95% CI 2.00 to 24.24, P=0.002) and patients who received regular follow-up had a decrease in the risk of death by approximately 81% compared to those who did not receive regular follow-up (HR=0.19, 95% CI 0.05 to 0.77, P=0.020). In the results of Bayesian Cox regression model, the iterative history plot and Blue/Green/Red (BGR) plot for each parameter showed the good model convergence, and parameter estimation indicated that the risk of death in patients with a positive first sputum culture was lower than that of patients with a negative first sputum culture (HR=0.33, 95% CI 0.08 to 0.87). Additionally, compared to patients without complications, those with comorbidities had an approximately 6.80-fold increase in the risk of death (HR=7.80, 95% CI 1.90 to 21.91). Patients who received regular follow-up had a 90% reduction in the risk of death compared to those who did not receive regular follow-up (HR=0.10, 95% CI 0.01 to 0.30). The comparison between these 2 models showed that the parameter standard deviations and corresponding 95% CI ranges of other variables in the Bayesian Cox model were significantly smaller than those in the conventional model, except for parameter standard deviations of receiving regular follow-up (Bayesian model was 0.77; conventional model was 0.72) and pulmonary cavities (Bayesian model was 0.73; conventional model was 0.73).

CONCLUSIONS

The first year of anti-TB therapy is a high-risk period for mortality in MDR-TB patients. Complications are the main risk factors of death in MDR-TB patients, while patients who received regular follow-up and had positive first sputum culture presented a lower risk of death. For data with a small sample size and low incidence of outcome, the Bayesian Cox regression model provides more reliable parameter estimation than the conventional Cox model.

The Long-Term Mortality Effects Associated with Exposure to Particles and NOx in the Malmö Diet and Cancer Cohort

In this study, the long-term mortality effects associated with exposure to PM10 (particles with an aerodynamic diameter smaller than or equal to 10 µm), PM2.5 (particles with an aerodynamic diameter smaller than or equal to 2.5 µm), BC (black carbon), and NOx (nitrogen oxides) were analyzed in a cohort in southern Sweden during the period from 1991 to 2016. Participants (those residing in Malmö, Sweden, born between 1923 and 1950) were randomly recruited from 1991 to 1996. At enrollment, 30,438 participants underwent a health screening, which consisted of questionnaires about lifestyle and diet, a clinical examination, and blood sampling. Mortality data were retrieved from the Swedish National Cause of Death Register. The modeled concentrations of PM10, PM2.5, BC, and NOx at the cohort participants' home addresses were used to assess air pollution exposure. Cox proportional hazard models were used to estimate the associations between long-term exposure to PM10, PM2.5, BC, and NOx and the time until death among the participants during the period from 1991 to 2016. The hazard ratios (HRs) associated with an interquartile range (IQR) increase in each air pollutant were calculated based on the exposure lag windows of the same year (lag0), 1-5 years (lag1-5), and 6-10 years (lag6-10). Three models were used with varying adjustments for possible confounders including both single-pollutant estimates and two-pollutant estimates. With adjustments for all covariates, the HRs for PM10, PM2.5, BC, and NOx in the single-pollutant models at lag1-5 were 1.06 (95% CI: 1.02-1.11), 1.01 (95% CI: 0.95-1.08), 1.07 (95% CI: 1.04-1.11), and 1.11 (95% CI: 1.07-1.16) per IQR increase, respectively. The HRs, in most cases, decreased with the inclusion of a larger number of covariates in the models. The most robust associations were shown for NOx, with statistically significant positive HRs in all the models. An overall conclusion is that road traffic-related pollutants had a significant association with mortality in the cohort.

Bivariate copula regression models for semi-competing risks

Time-to-event semi-competing risk endpoints may be correlated when both events occur on the same individual. These events and the association between them may also be influenced by individual characteristics. In this article, we propose copula survival models to estimate hazard ratios of covariates on the non-terminal and terminal events, along with the effects of covariates on the association between the two events. We use the Normal, Clayton, Frank and Gumbel copulas to provide a variety of association structures between the non-terminal and terminal events. We apply the proposed methods to model semi-competing risks of graft failure and death for kidney transplant patients. We find that copula survival models perform better than the Cox proportional hazards model when estimating the non-terminal event hazard ratio of covariates. We also find that the inclusion of covariates in the association parameter of the copula models improves the estimation of the hazard ratios.

A Comparison of Statistical Analysis Between "Real" Patients Reported in Kaplan-Meier Curves and "Reconstructed" Patients Estimated Through the IPDfromKM Method: Analysis of Eight Trials Evaluating Catheter Ablation of Ventricular Tachycardia

Time-to-event endpoints are most widely used in oncology and, to a lesser extent, in cardiology. Typical statistical parameters employed in this context include overall survival, progression-free survival, and recurrence-free survival. The graphical presentation of the results is based on the Kaplan-Meier plot. When Kaplan-Meier curves are included in a meta-analysis, the typical methodological approach is a simplified one because the results of each trial (as well as those of the meta-analysis itself) are expressed through a 2x2 contingency; the methodological simplification is that the follow-up is left out from the analysis and, consequently, the Kaplan-Meier curves are omitted as well. The IPDfromKM method, developed in 2021, is an artificial intelligence algorithm designed to be used in these situations. According to this method, to keep the Kaplan-Meier curves in the meta-analysis, each curve is converted into a database of individual patients (which are denoted as "reconstructed" individual patients). In this way, for the purposes of the meta-analysis, the statistical methods are based on individual patients (like those of clinical trials) so that the Kaplan-Meier curves must not be excluded, and the effect of the follow-up can, therefore, be investigated. This technical report describes the IPDfromKM method in all of its operational details. To present the method, a meta-analysis investigating the effects of catheter ablation to prevent ventricular tachyarrhythmia (VT) has been taken as an example. The original meta-analysis, which included nine controlled trials, was published in February 2023 and adopted the simplified approach based on 2x2 contingency tables. We have reanalyzed these trials by using the IPDfromKM method. Overall, both the standard binary meta-analysis and the IPDfromKM method showed that ablation significantly reduces VT recurrence (hazard ratio, 0.820 for binary meta-analysis vs 0.728 for the IPDfromKM method). By contrast, while no heterogeneity was found by the binary method, the IPDfromKM found significant heterogeneity, which was confirmed by visual inspection of the Kaplan-Meier curves. This suggests that the results of the IPDfromKM method are more accurate because they include the effect of the follow-up on patients' outcomes. In conclusion, our reanalysis confirms the significant benefit determined by ablation, but a more pronounced degree of between-trial heterogeneity has been found. Finally, it should be stressed that, outside the field of meta-analysis, the IPDfromKM method is also applicable to carry out an indirect comparison between treatments that have never been compared in real clinical trials. In this case, reconstructed patients are analyzed by conducting a simulated comparative trial.

Survival rates and mortality risks of Plecturocebus cupreus at the California National Primate Research Center

This article describes survivorship and explores factors affecting mortality risks in a captive colony of coppery titi monkeys (Plecturocebus cupreus) housed at the California National Primate Research Center (CNPRC), at UC Davis, in Davis, CA. We analyzed data collected on individuals since the colony's creation in the 1960s, with a sample of 600 animals with partially complete information (date of birth, age at death, body mass, parental lineage). We used three methods: (1) Kaplan-Meier regressions followed by a log-rank test to compare survival in male and female titi monkeys, (2) a breakpoint analysis to identify shifts in the survival curves, and (3) Cox regressions to test the effect of body mass change, parental pair tenure, and parental age on mortality risk. We found that males tend to have a longer median lifespan than females (14.9 and 11.4 years; p = 0.094) and that survival decreases earlier in males than in females during adulthood (9.8 and 16.2 years). A body mass loss of 10% from adulthood to the time of death led to a 26% higher risk of dying (p < 0.001) as compared to an individual with stable body mass. We found no evidence of sociobiological factors on mortality risks (parental age, parental pair tenure), but an exploratory analysis suggested that a higher rate of offspring conceptions increases mortality risks. This description of factors influencing survival and mortality in titi monkeys is a first step toward understanding aging in this species to consider titi monkeys as a primate model for socioemotional aging.

Relationship between Prostate Inflammation and Periodontal Disease-A Systematic Review and Meta-Analysis

The aim of this systematic review and meta-analysis was to analyze the association between periodontal disease and prostate inflammation with a null hypothesis stating that periodontal disease does not increase the incidence of prostate inflammation.

MATERIALS AND METHODS

A systematic literature review and meta-analysis of longitudinal observational cohort and case-control studies that evaluated the odds ratio or hazard ratio and confidence interval was undertaken based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations (2020). A total of four databases were consulted in the literature search: PubMed-Medline, Scopus, Embase, and Web of Science. After eliminating duplicated articles and applying the inclusion criteria, seven articles were selected for the qualitative and quantitative analyses.

RESULTS

Four observational cohort studies and three observational cohort case-control studies were included in the meta-analysis. The four observational cohort studies were combined using the random effects model to estimate a hazard ratio of 1.32 with a confidence interval of 95% between 0.87 and 1.77. The meta-analysis presented high heterogeneity (Q test = 56.1; p value < 0.001; I2 = 94.9%). Moreover, the three observational case-control studies were combined using the random effects model to estimate an odds ratio of 1.62 with a confidence interval of 95% between 1.41 and 1.84. The meta-analysis presented high heterogeneity (Q test = 1.07; p value = 0.782; I2 = 0%).

CONCLUSIONS

The incidence of periodontal disease does not increase the risk of the incidence of prostate inflammation.

Time to onset of cardiovascular and cerebrovascular outcomes after hypertensive disorders of pregnancy: a nationwide, population-based retrospective cohort study

BACKGROUND

The increased maternal cardiocerebrovascular risk after a pregnancy complicated by hypertensive disorders of pregnancy, is well documented in the literature. Recent evidence has suggested a shorter timeframe for the development of these postnatal outcomes, which could have major clinical implications.

OBJECTIVE

This study aimed to determine the risk of and time to onset of maternal cardiovascular and cerebrovascular outcomes after a pregnancy complicated by hypertensive disorders of pregnancy.

STUDY DESIGN

This study included 2,227,711 women, without preexisting chronic hypertension, who delivered during the period 2008 to 2010: 37,043 (1.66%) were diagnosed with preeclampsia, 34,220 (1.54%) were diagnosed with gestational hypertension, and 2,156,448 had normotensive pregnancies. Hospitalizations for chronic hypertension, heart failure, coronary heart disease, cerebrovascular disease, and peripheral arterial disease were studied. A classical Cox regression was performed to estimate the average effect of hypertensive disorders of pregnancy over 10 years compared with normotensive pregnancy; moreover, an extended Cox regression was performed with a step function model to estimate the effect of the exposure variable in different time intervals: <1, 1 to 3, 3 to 5, and 5 to 10 years of follow-up.

RESULTS

The risk of chronic hypertension after a pregnancy complicated by preeclampsia was 18 times higher in the first year (adjusted hazard ratio, 18.531; 95% confidence interval, 16.520-20.787) to only 5 times higher at 5 to 10 years after birth (adjusted hazard ratio, 4.921; 95% confidence interval, 4.640-5.218). The corresponding risks of women with gestational hypertension were 12 times higher (adjusted hazard ratio, 11.727; 95% confidence interval, 10.257-13.409]) and 6 times higher (adjusted hazard ratio, 5.854; 95% confidence interval, 5.550-6.176), respectively. For other cardiovascular and cerebrovascular outcomes, there was also a significant effect with preeclampsia (heart failure: adjusted hazard ratio, 6.662 [95% confidence interval, 4.547-9.762]; coronary heart disease: adjusted hazard ratio, 3.083 [95% confidence interval, 1.626-5.844]; cerebrovascular disease: adjusted hazard ratio, 3.567 [95% confidence interval, 2.600-4.893]; peripheral arterial disease: adjusted hazard ratio, 4.802 [95% confidence interval, 2.072-11.132]) compared with gestational hypertension in the first year of follow-up. A dose-response effect was evident for the severity of preeclampsia with the averaged 10-year adjusted hazard ratios for developing chronic hypertension after early, preterm, and late preeclampsia being 10, 7, and 6 times higher, respectively.

CONCLUSION

The risks of cardiovascular and cerebrovascular outcomes were the highest in the first year after a birth complicated by hypertensive disorders of pregnancy. We found a significant relationship with both the severity of hypertensive disorders of pregnancy and the gestational age of onset suggesting a possible dose-response relationship for the development of cardiovascular and cerebrovascular outcomes. These findings call for an urgent focus on research into effective postnatal screening and cardiocerebrovascular risk prevention for women with hypertensive disorders of pregnancy.

The role of Bacillus Calmette-Guérin administration on the risk of dementia in bladder cancer patients: a systematic review and meta-analysis

Background

Previous cohort studies have found an association between Bacillus Calmette-Guérin (BCG) administration and incident dementia. In the systematic review and meta-analysis, we aimed to summarize the current evidence of the effect of BCG use on the risk of developing dementia.

Methods

We searched six databases until 20 May 2023 for studies investigating the risk of dementia and BCG administration. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were pooled in the meta-analysis. Meta-regression, subgroup, and sensitivity analysis were conducted as well.

Results

Of the 4,043 records initially evaluated, five articles were included for final analysis, with a total of 45,407 bladder cancer (BC) patients. All five studies were evaluated and rated as with high quality, and a low possibility of publication bias was indicated. A significant association between BCG and the incidence of dementia in BC patients was found in all five studies. Although a high heterogeneity (I2 = 84.5%, p < 0.001) was observed, the pooled HR was 0.55 (0.42-0.73), indicating that BCG exposure or treatment reduced the risk of incident dementia by 45%. Moreover, the sensitivity analysis showed good robustness of the overall effect with no serious publication bias.

Conclusion

BCG administration is associated with a significantly lower risk of developing dementia. However, an epidemiological cohort is needed to establish a relationship between BCG use and incident dementia in the normal population. Once the relationship is confirmed, more people may benefit from the association.

Systematic review registration

identifier: CRD42023428317.

Risks after Gestational Diabetes Mellitus in Taiwanese Women: A Nationwide Retrospective Cohort Study

OBJECTIVE

An increasing trend in the prevalence of gestational diabetes mellitus (GDM) has been reported in Taiwan. GDM has been linked to various adverse maternal outcomes over a long period, including cardiovascular disease (CVD) and chronic kidney disease (CKD). However, evidence implies that the effects of GDM on the mid-term surrogate risk factors for these diseases are limited. Furthermore, data from nationwide cohort studies are limited. The primary aim of this study was to investigate the risk of developing type 2 diabetes mellitus (T2DM), arterial hypertension (aHTN), and hyperlipidemia (HL) through a 5-year follow-up post-delivery of women with GDM in a nationwide cohort study in Taiwan. The second objective was to investigate the risk of developing insulin resistance syndrome (IRS)-related diseases, including CVD, acute myocardial infarction (AMI), peripheral artery occlusive disease (PAOD), non-alcoholic fatty liver diseases (NAFLD), and CKD.

METHODS

This was a retrospective, population-based nationwide cohort study. The data source comprises a merge of the Birth Certificate Application Database (BCA) and the National Health Insurance Research Database in Taiwan. Women aged between 15 and 45 years who gave birth in Taiwan between 2004 and 2011 were included. Women who were enrolled and had a GDM diagnosis were assigned to the exposure group. Women who were enrolled without a GDM diagnosis were assigned to the comparison group. The relative risk of developing T2DM, aHTN, HL, and IRS-related diseases, including CVD, AMI, PAOD, NAFLD, and CKD, were analyzed and presented as hazard ratio (HR) through Cox regression and log-rank regression analyses.

RESULTS

A total of 1,180,477 women were identified through the BCA database between 2004 and 2011. Of those, 71,611 GDM-diagnosed women and 286,444 women without GDM were included in the final analysis. After adjusting for age, pre-existing cancer, and parity, developing T2DM, aHTN, and HL were still significantly increased in the GDM group (HR and interquartile range (IQR): 2.83 (2.59, 3.08), 1.09 (1.01, 1.06), and 1.29 (1.20, 1.38), accordingly). CVD, NAFLD, and CKD had a very low incidence and showed insignificant results.

CONCLUSION

Our findings provide nationwide cohort data showing that GDM increased the risk of developing T2DM, aHTN, and HL 5 years after delivery within the same group. The GDM complications and risk of CVD, AMI, PAOD, NAFLD, and CKD need further investigation.

Survival Analysis, Kaplan-Meier Curves, and Cox Regression: Basic Concepts

Survival analysis is used to analyze data from patients who are followed for different periods of time and in whom the outcome of interest, a dichotomous event, may or may not have occurred at the time the study is halted; data from all patients are used in the analysis, including data from patients who dropped out, regardless of the duration of follow-up. This article discusses basic concepts in survival analysis, explains technical terms such as censoring, and provides reasons why ordinary methods of analysis cannot be applied to such data. The Kaplan-Meier survival curve is described, as is the Cox proportional hazards regression and the hazard ratio. Supplementary information includes a data file, graphs with explanations, and additional discussions; these are provided to enhance the reader's experience and understanding.

Hazard ratios of second primary malignancy after radioiodine for differentiated thyroid carcinoma: a large-cohort retrospective study

INTRODUCTION

The objective of this study is to evaluate the benefits of radioactive iodine (RAI) treatment and the risk of second primary malignancy (SPM) in RAI-treated patients.

MATERIAL AND METHODS

The cohort for this analysis consisted of individuals diagnosed with a first primary differentiated thyroid carcinoma (DTC), reported by the Surveillance, Epidemiology, and End Results (SEER) database in 1988-2016. Overall survival (OS) difference was estimated by Kaplan-Meier curves and log-rank test, and hazard ratios (HR) were obtained by Cox proportional-hazards model to evaluate the association between RAI and SPM.

RESULTS

Among 130,902 patients, 61,210 received RAI and 69,692 did not, and a total of 8604 patients developed SPM. We found that OS was significantly higher in patients who received RAI than in those who did not (p < 0.001). DTC survivors treated with RAI had increased risk of SPM in females (p = 0.043), particularly for SPM occurring in the ovary (p = 0.039) and leukaemia (p < 0.0001). The risk of developing SPM was higher in the RAI group than in the non-RAI group and the general population, and the incidence increased with age.

CONCLUSIONS

Increased risk of SPM occurs in female DTC survivors treated with RAI, which become more obvious with increasing age. Our research findings were beneficial to the formulation of RAI treatment strategies and the prediction of SPM for patients with thyroid cancer of different genders and different ages.

Risk of systemic autoimmune diseases with antiarrhythmic drugs in arrhythmia patients: A retrospective cohort study

AIM

The risk factors for systemic autoimmune disease (SAD)s with antiarrhythmic drug(AAD)s in arrhythmia patients are still unclear. This study was discussed this risk factors for SADs with AADs in arrhythmia patients.

METHODS

This study was a retrospective cohort design and analyzed this relationship in an Asian population. Patients without a prior diagnosis of SADs were identified from Taiwan's National Health Insurance Research Database from January 1, 2000 to December 31, 2013. Cox regression models were estimated the hazard ratio (HR) with 95% confidence interval [CI] of SAD.

RESULTS

We estimated the data of participants aged ≧ 20 or ≦ 100 years old and free of SADs at baseline. AAD users (n = 138376) had a significantly increased risk of SADs over non-AAD users. There was a significant higher risk of developing SADs in all age and sex categories. The patients who received AADs, the autoimmune disease with the significantly higher risk was systemic lupus erythematous (SLE) (adjusted HR [aHR] 1.53, 95%CI, 1.04-2.26), Sjögren syndrome (SjS) (adjusted HR [aHR] 2.06, 95%CI, 1.59-2.66) and rheumatoid arthritis (RA) (aHR, 1.57, 95%CI, 1.26-1.94).

CONCLUSION

We concluded that there were statistical associations between AADs and SADs, and the higher incidence was SLE, SjS and RA in arrhythmia patients.

Studentized permutation method for comparing two restricted mean survival times with small sample from randomized trials

Recent observations, especially in cancer immunotherapy clinical trials with time-to-event outcomes, show that the commonly used proportional hazard assumption is often not justifiable, hampering an appropriate analysis of the data by hazard ratios. An attractive alternative advocated is given by the restricted mean survival time (RMST), which does not rely on any model assumption and can always be interpreted intuitively. Since methods for the RMST based on asymptotic theory suffer from inflated type-I error under small sample sizes, a permutation test was proposed recently leading to more convincing results in simulations. However, classical permutation strategies require an exchangeable data setup between comparison groups which may be limiting in practice. Besides, it is not possible to invert related testing procedures to obtain valid confidence intervals, which can provide more in-depth information. In this paper, we address these limitations by proposing a studentized permutation test as well as respective permutation-based confidence intervals. In an extensive simulation study, we demonstrate the advantage of our new method, especially in situations with relatively small sample sizes and unbalanced groups. Finally, we illustrate the application of the proposed method by re-analyzing data from a recent lung cancer clinical trial.

On assessing survival benefit of immunotherapy using long-term restricted mean survival time

The pattern of the difference between two survival curves we often observe in randomized clinical trials for evaluating immunotherapy is not proportional hazards; the treatment effect typically appears several months after the initiation of the treatment (ie, delayed difference pattern). The commonly used logrank test and hazard ratio estimation approach will be suboptimal concerning testing and estimation for those trials. The long-term restricted mean survival time (LT-RMST) approach is a promising alternative for detecting the treatment effect that potentially appears later in the study. A challenge in employing the LT-RMST approach is that it must specify a lower end of the time window in addition to a truncation time point that the RMST requires. There are several investigations and suggestions regarding the choice of the truncation time point for the RMST. However, little has been investigated to address the choice of the lower end of the time window. In this paper, we propose a flexible LT-RMST-based test/estimation approach that does not require users to specify a lower end of the time window. Numerical studies demonstrated that the potential power loss by adopting this flexibility was minimal, compared to the standard LT-RMST approach using a prespecified lower end of the time window. The proposed method is flexible and can offer higher power than the RMST-based approach when the delayed treatment effect is expected. Also, it provides a robust estimate of the magnitude of the treatment effect and its confidence interval that corresponds to the test result.

Oncologic outcomes of intersphincteric resection versus abdominoperineal resection for lower rectal cancer: a systematic review and meta-analysis

BACKGROUND

The efficacy of intersphincteric resection (ISR) surgery for patients with lower rectal cancer remains unclear compared to abdominoperineal resection (APR). The aim of this study is to compare the oncologic outcomes for lower rectal cancer patients after ISR and APR through a systematic review and meta-analysis.

MATERIALS AND METHODS

A systematic electronic search of the Cochrane Library, PubMed, EMBASE, and MEDLINE was performed through January 12, 2022. The primary outcomes included 5-year disease-free survival (5y-DFS) and 5-year overall survival. Secondary outcomes included circumferential resection margin involvement, local recurrence, perioperative outcomes, and other long-term outcomes. The pooled odds ratios, mean difference, or hazard ratios (HRs) of each outcome measurement and their 95% CIs were calculated.

RESULTS

A total of 20 nonrandomized controlled studies were included in the qualitative analysis, with 1217 patients who underwent ISR and 1135 patients who underwent APR. There was no significant difference in 5y-DFS (HR: 0.84, 95% CI: 0.55-1.29; P=0.43) and 5-year overall survival (HR: 0.93, 95% CI: 0.60-1.46; P=0.76) between the two groups. Using the results of five studies that reported matched T stage and tumor distance, we performed another pooled analysis. Compared to APR, the ISR group had equal 5y-DFS (HR: 0.76, 95% CI: 0.45-1.30; P=0.31) and 5y-LRFS (local recurrence-free survival) (HR: 0.72, 95% CI: 0.29-1.78; P=0.48). Meanwhile, ISR had equivalent local control as well as perioperative outcomes while significantly reducing the operative time (mean difference: -24.89, 95% CI: -45.21 to -4.57; P=0.02) compared to APR.

CONCLUSIONS

Our results show that the long-term survival and safety of patients is not affected by ISR surgery, although this result needs to be carefully considered and requires further study due to the risk of bias and limited data.

Robust weights that optimally balance confounders for estimating marginal hazard ratios

Covariate balance is crucial in obtaining unbiased estimates of treatment effects in observational studies. Methods that target covariate balance have been successfully proposed and largely applied to estimate treatment effects on continuous outcomes. However, in many medical and epidemiological applications, the interest lies in estimating treatment effects on time-to-event outcomes. With this type of data, one of the most common estimands of interest is the marginal hazard ratio of the Cox proportional hazards model. In this article, we start by presenting robust orthogonality weights, a set of weights obtained by solving a quadratic constrained optimization problem that maximizes precision while constraining covariate balance defined as the correlation between confounders and treatment. By doing so, robust orthogonality weights optimally deal with both binary and continuous treatments. We then evaluate the performance of the proposed weights in estimating marginal hazard ratios of binary and continuous treatments with time-to-event outcomes in a simulation study. We finally apply robust orthogonality weights in the evaluation of the effect of hormone therapy on time to coronary heart disease and on the effect of red meat consumption on time to colon cancer among 24,069 postmenopausal women enrolled in the Women's Health Initiative observational study.

Association of Antihistamine Use with Increased Risk of Esophageal Squamous Cell Carcinoma: A Nationwide, Long-Term Follow-Up Study Using Propensity Score Matching

Esophageal cancer is a common and aggressive cancer, with a five-year survival rate of approximately 20%. Therefore, identifying safe and effective medications that can reduce the risk of esophageal cancer is of great importance.

OBJECTIVE

To examine the association between H1-antihistamines (AHs) use and the incidence of esophageal squamous cell carcinoma (ESCC) in a head-to-head propensity score matching (PSM) comparative study.

DESIGN

Retrospective cohort study.

SETTING

Nationwide population-based study in Taiwan.

PARTICIPANTS

1289,526 adults from the National Health Insurance Research Database from 2008 to 2018.

EXPOSURES

AH use.

MAIN OUTCOMES AND MEASURES

Incidence rates (IRs), incidence rate ratios (IRRs), and adjusted hazard ratios (aHRs) of ESCC in AH users compared with nonusers.

RESULTS

AH users had a significantly higher IR of ESCC than nonusers (1.47 vs. 1.36 per 100,000 person-years). The IRR (95% CI) for ESCC was 1.18 (1.08-1.28) in AH users compared with nonusers. After adjustment for age, sex, income levels, urbanization, cigarettes smoking, alcoholic related diseases, comorbidities, medication use, and Charlson Comorbidity Index scores, the aHR (95% CI) for ESCC was 1.22 (1.12-1.33) in AH users compared with nonusers. A dose-response relationship was also observed, with aHRs for AH use at 28-182, 183-488, 489-1043, and >1043 cumulative defined daily doses (cDDDs) of 1.12, 1.20, 1.25, and 1.37, respectively, compared with <28 cDDDs.

CONCLUSIONS AND RELEVANCE

Our study found a significant association between AH use and the increased risk of ESCC, with a dose-response relationship. This study suggests that AH use may increase the risk of ESCC, especially at high doses, and highlights the importance of caution when prescribing AHs.

A Simple, Test-Based Method to Control the Overestimation Bias in the Analysis of Potential Prognostic Tumour Markers

The early evaluation of prognostic tumour markers is commonly performed by comparing the survival of two groups of patients identified on the basis of a cut-off value. The corresponding hazard ratio (HR) is usually estimated, representing a measure of the relative risk between patients with marker values above and below the cut-off. A posteriori methods identifying an optimal cut-off are appropriate when the functional form of the relation between the marker distribution and patient survival is unknown, but they are prone to an overestimation bias. In the presence of a small sample size, which is typical of rare diseases, the external validation sets are hardly available and internal cross-validation could be unfeasible. We describe a new method to obtain an unbiased estimate of the HR at an optimal cut-off, exploiting the simple relation between the HR and the associated p-value estimated by a random permutation analysis. We validate the method on both simulated data and set of gene expression profiles from two large, publicly available data sets. Furthermore, a reanalysis of a previously published study, which included 134 Stage 4S neuroblastoma patients, allowed for the identification of E2F1 as a new gene with potential oncogenic activity. This finding was confirmed by an immunofluorescence analysis on an independent cohort.

CtDNA's prognostic value in patients with early-stage colorectal cancer after surgery: A meta-analysis and systematic review

BACKGROUND

Circulating tumor DNA (ctDNA) positivity has been shown to suggest the presence of minimally residual tumor cells in numerous investigations. We aimed to assess the prognostic value of ctDNA positivity for recurrence-free survival in patients with early-stage colorectal cancer after radical surgery and following adjuvant chemotherapy.

METHODS

We systematically reviewed studies published in English until August 15, 2022, concerning ctDNA and tumor-node-metastasis I to III colorectal cancer after surgery, and quantified the correlation between ctDNA positivity and early-stage (tumor-node-metastasis stage I-III) colorectal cancer using meta-analysis methods.

RESULTS

In total, the meta-analysis comprised 1713 patients from 6 studies. Patients with ctDNA-positive colorectal cancer after surgery had a significantly higher risk of recurrence than patients with ctDNA-negative colorectal cancer (hazard ratio 4.64, 95% confidence interval 2.17-9.92, z = 3.96; P < .001). After adjuvant chemotherapy, patients who were ctDNA-positive had a significantly higher risk of recurrence than those who were ctDNA-negative (hazard ratio 7.27, 95% confidence interval 4.50-11.75, z = 8.1; P < .001).

CONCLUSIONS

CtDNA positivity may potentially be a predictor for early-stage colorectal tumor recurrence following surgery and adjuvant chemotherapy.

Investigations of methods for multiple time-to-event endpoints: A chronic myeloid leukemia data analysis

BACKGROUND

In randomized controlled trials, multiple time-to-event endpoints are commonly used to determine treatment effects. However, choosing an appropriate method to address multiple endpoints, according to different purposes of clinical practice, is a challenge for researchers.

METHODS

We applied single endpoint, composite endpoint and win ratio analysis to chronic myeloid leukemia (CML) data to illustrate the distinctions with different multiple endpoints, including relapse, recovery and death after transplantation.

RESULTS

Regarding relapse and death, the hazard ratio in single endpoint analysis (HR_s ) were 1.281 (95% CI: 1.061-1.546) and hazard ratio in composite endpoint analysis (HR_c ) were 1.286 (95% CI: 1.112-1.486) and 1/WR (win ratio) was 1.292 (95% CI: 1.115-1.497) indicated a similar negative effect for non-prophylaxis patients. However, when considering recovery and death, the corresponding HR_s  = 1.280 (95% CI: 1.056-1.552) may not be enough to describe the effect on death with nonproportional hazards (p < 0.05), and for the composite endpoint analysis, the HR_c  = 0.828 (95% CI: 0.740-0.926) cannot quantify and interpret the clinical effect on the composite endpoint with the combination of recovery and death, while the 1/WR = 1.351 (95% CI: 1.207-1.513) showed an unfavourable effect for non-prophylaxis patients CONCLUSIONS: When dealing with multiple endpoints, single endpoints, researchers may choose single endpoints, composite endpoints and WR analysis due to different clinical applications and purposes. However, both single and composite endpoint analyses are hazard-based measures, and thus, the proportional hazards assumption should be considered. Moreover, composite endpoint analysis should be applied for endpoints with similar clinical meanings but not opposing implications. Win ratio analysis can be considered for different clinical importance of multiple endpoints, but the meaning of 'winner' needs to be specified for desired or undesired endpoints.

Finding the Proportion of Females with Autistic Spectrum Disorder Who Develop Anorexia Nervosa, the True Prevalence of Female ASD and Its Clinical Significance

It appears that up to 80% of females with autistic spectrum disorder (ASD) have not been diagnosed by the age of 18. This translates to a prevalence of about 5-6%, and if true, has serious implications for female mental health. One way of finding the true value is to use Bayes' Theorem with a comorbid condition as a more easily recognizable flag. An obvious choice is anorexia nervosa (AN), but it transpires that the proportion of women with ASD who develop AN is unknown. This study uses published data in novel ways to provide two methods of estimating a range for this variable, and gives a median value of 8.3% for AN in ASD and, with four other methods, a median prevalence of 6% for female ASD. The clinical implications of the diagnosis and management of ASD and its comorbidities are discussed and, as an example, a solution is provided for the rate of ASD in symptomatic generalized joint hypermobility. It is probable that one in six women with a mental health condition is autistic.

Independent and Joint Associations of BMI and Waist Circumference With the Onset of Type 2 Diabetes Mellitus in Chinese Adults: Prospective Data Linkage Study

BACKGROUND

General obesity and abdominal obesity, typically measured by BMI and waist circumference (WC), respectively, are associated with an increased risk of type 2 diabetes mellitus (T2DM). However, the magnitude of the association of these two obesity indicators and their joint association with the onset of T2DM remain controversial.

OBJECTIVE

The aim of this study was to investigate the associations between these two obesity indicators and T2DM among the Chinese population to contribute scientific evidence for appropriate T2DM interventions.

METHODS

A cohort of 3001 eligible participants was selected from the Ningbo Adult Chronic Disease Surveillance Project running since 2015. Based on BMI, individuals were categorized into groups of underweight or normal, overweight, and obesity. Based on WC, individuals were categorized in groups of normal, precentral obesity, and central obesity. Follow-up was performed by linking data of the baseline data set with the diabetes registry data set and the vital registry data set (both from the Ningbo Municipal Integrated Noncommunicable Disease Collaborative Management System), mainly using the participants' identity numbers. Follow-up was completed when a participant was diagnosed with T2DM. The associations were estimated with multivariate Cox proportional hazard regression.

RESULTS

In the cohort, 90 of 3001 participants developed T2DM (incidence density: 6.483/1000 person-years) with a median 4.72 years of follow-up. After controlling for age, sex, hypertension, dyslipidemia, smoking status, and family history of diabetes, the multivariate adjusted hazard ratios (HRs) across underweight/normal, overweight, and obesity BMI categories were 1.000, 1.653 (95% CI 1.030-2.654), and 2.375 (95% CI 1.261-4.473), respectively. The multivariate adjusted HRs across the normal, precentral obesity, and central obesity WC categories were 1.000, 1.215 (95% CI 0.689-2.142), and 1.663 (95% CI 1.016-2.723), respectively. Compared with the reference group (normal WC with an underweight/normal BMI), the multivariate adjusted HR for participants with both central obesity according to WC and obesity according to BMI was 2.489 (95% CI 1.284-4.825).

CONCLUSIONS

Both elevated BMI and WC at baseline increased the risk of T2DM. Compared with WC, BMI as an obesity indicator was more strongly associated with the onset of T2DM.

Treatment effect measures under nonproportional hazards

In a clinical trial with a time-to-event endpoint the treatment effect can be measured in various ways. Under proportional hazards all reasonable measures (such as the hazard ratio and the difference in restricted mean survival time) are consistent in the following sense: Take any control group survival distribution such that the hazard rate remains above zero; if there is no benefit by any measure there is no benefit by all measures, and as the magnitude of treatment benefit increases by any measure it increases by all measures. Under nonproportional hazards, however, survival curves can cross, and the direction of the effect for any pair of measures can be inconsistent. In this paper we critically evaluate a variety of treatment effect measures in common use and identify flaws with them. In particular, we demonstrate that a treatment's benefit has two distinct and independent dimensions which can be measured by the difference in the survival rate at the end of follow-up and the difference in restricted mean survival time, and that commonly used measures do not adequately capture both dimensions. We demonstrate that a generalized hazard difference, which can be estimated by the difference in exposure-adjusted subject incidence rates, captures both dimensions, and that its inverse, the number of patient-years of follow-up that results in one fewer event (the NYNT), is an easily interpretable measure of the magnitude of clinical benefit.

Galectin-3 is Associated with Heart Failure Incidence: A Meta-Analysis

INTRODUCTION

Heart failure (HF) is a leading cause of death worldwide. The global prevalence of heart failure is projected to increase rapidly in the coming decades, and significant attention has turned to improving biomarker-based risk prediction of incident HF. This paper aimed to qualitatively and quantitatively evaluate the evidence associating levels of galectin-3 with the risk of incident HF.

METHODS

A review of PUBMED-indexed peer-reviewed literature was performed. Nine studies met the inclusion criteria, and all nine had data eligible for conversion and pooling. A randomeffects meta-analysis was performed using hazard ratios and 95% confidence intervals from a minimally adjusted model, a further adjusted model, and from subgroups within the further-adjusted model.

RESULTS

The minimally-adjusted model provided an HR of 1.97 (95% CI 1.74-2.23) when comparing the top quartile of log-gal-3 to the bottom quartile. The further-adjusted model provided an HR of 1.32 (95% CI 1.21-1.44) for the same comparison. The positive, significant association was conserved during sensitivity analysis.

CONCLUSION

There is a significant positive association between circulating galectin-3 and the risk of incident heart failure. Given the complex mechanistic relationship between galectin-3 and cardiovascular pathophysiology, further investigation is recommended for the possible implementation of galectin-3 into clinical risk prediction models.

Increased risk of type 2 diabetes in patients with systemic lupus erythematosus: A nationwide cohort study in Taiwan

Data on the risk of developing diabetes in patients with systemic lupus erythematosus (SLE) are limited and have yielded mixed results. We conducted a nationwide cohort study to investigate the risk of subsequent type 2 diabetes in patients with SLE compared with matched non-SLE controls. Data were collected from the Taiwan National Health Insurance Research Database. Adult patients newly diagnosed with SLE between 2003 to 2010 were identified as the study cohort. The non-SLE group was matched for age, gender, and date of initial diagnosis as the comparison cohort. A total of 6159 SLE patients (87.90% female, mean age 38.79 years) were identified during this period. Of these, 206 (3.34%) developed type 2 diabetes. The 3-year incidence of type 2 diabetes was significantly higher in the SLE cohort than in the control group (130.26 vs 101.18 cases per 10,000 person-years), with an adjusted hazard ratio of 1.22 (95% confidence interval [CI] 1.04-1.44), after adjusting for age, gender, underlying comorbidities, and monthly income. Stratified analyses showed that women with SLE and low-income SLE patients (monthly income < 20,000 New Taiwan Dollar) had a higher risk of type 2 diabetes than non-SLE controls, with adjusted hazard ratios of 1.21 (95% CI 1.01-1.45) and 1.36 (95% CI 1.10-1.69), respectively. Patients with newly diagnosed SLE had a 22% increased risk of developing type 2 diabetes during the 3-year follow-up period compared with matched controls.

Clinical Investigation of Chemotherapeutic Resistance and miRNA Expressions in Head and Neck Cancers: A Thorough PRISMA Compliant Systematic Review and Comprehensive Meta-Analysis

Background: Chemoresistance is a significant barrier to combating head and neck cancer, and decoding this resistance can widen the therapeutic application of such chemotherapeutic drugs. This systematic review and meta-analysis explores the influence of microRNA (miRNA) expressions on chemoresistance in head and neck cancers (HNC). The objective is to evaluate the theragnostic effects of microRNA expressions on chemoresistance in HNC patients and investigate the utility of miRNAs as biomarkers and avenues for new therapeutic targets. Methods: We performed a comprehensive bibliographic search that included the SCOPUS, PubMed, and Science Direct bibliographic databases. These searches conformed to a predefined set of search strategies. Following the PRISMA guidelines, inclusion and exclusion criteria were framed upon completing the literature search. The data items extracted were tabulated and collated in MS Excel. This spreadsheet was used to determine the effect size estimation for the theragnostic effects of miRNA expressions on chemoresistance in HNC, the hazard ratio (HR), and 95% confidence intervals (95% CI). The comprehensive meta-analysis was performed using the random effects model. Heterogeneity among the data collected was assessed using the Q test, Tau², I², and Z measures. Publication bias of the included studies was checked using the Egger's bias indicator test, Orwin and classic fail-safe N test, Begg and Mazumdar rank collection test, and Duval and Tweedie's trim and fill methods. Results: After collating the data from 23 studies, dysregulation of 34 miRNAs was observed in 2189 people. These data were gathered from 23 studies. Out of the 34 miRNAs considered, 22 were up-regulated, while 12 were down-regulated. The TaqMan transcription kits were the most used miRNA profiling platform, and miR-200c was seen to have a mixed dysregulation. We measured the overall pooled effect estimate of HR to be 1.516 for the various analyzed miRNA at a 95% confidence interval of 1.303-1.765, with a significant p-value. The null hypothesis test's Z value was 5.377, and the p-value was correspondingly noted to be less than 0.0001. This outcome indicates that the risk of death is determined to be higher in up-regulated groups than in down-regulated groups. Among the 34 miRNAs that were investigated, seven miRNAs were associated with an improved prognosis, especially with the overexpression of these seven miRNAs (miR15b-5p, miR-548b, miR-519d, miR-1278, miR-145, miR-200c, Hsa- miR139-3p). Discussion: The findings reveal that intricate relationships between miRNAs' expression and chemotherapeutic resistance in HNC are more likely to exist and can be potential therapeutic targets. This review suggests the involvement of specific miRNAs as predictors of chemoresistance and sensitivity in HNC. The examination of the current study results illustrates the significance of miRNA expression as a theragnostic biomarker in medical oncology.

Early-Life Mebendazole Exposure Increases the Risk of Adult-Onset Ulcerative Colitis: A Population-Based Cohort Study

INTRODUCTION

According to the hygiene hypothesis, exposure to parasites may protect against inflammatory bowel disease (IBD). Our aim was to examine the risk of IBD with childhood exposure to mebendazole, a broad-spectrum antihelminthic agent.

METHODS

We conducted a population-based cohort study using prospectively collected historical data of all individuals born in Denmark between 1995 and 2018. We identified mebendazole exposure at age younger than 18 years and during early life (younger than 5 years). We performed adjusted Cox proportional hazards regression analysis to determine the risk of IBD, ulcerative colitis (UC), and Crohn's disease with mebendazole exposure after adjusting for potential confounders.

RESULTS

Of 1,520,290 individuals in the cohort, 615,794 had childhood or adolescence mebendazole exposure. One thousand five hundred fifty-five and 1,499 individuals were subsequently diagnosed with pediatric-onset and adult-onset IBD, respectively. On multivariable analysis, mebendazole exposure at age younger than 18 years did not affect pediatric-onset or adult-onset IBD risk (adjusted hazard ratio [aHR] 0.97, 95% confidence interval [CI] 0.87, 1.07, and 1.08, 95% CI 0.97, 1.19, respectively). On limiting mebendazole exposure to age younger than 5 years while there was no association with pediatric-onset IBD (aHR 0.98, 95% CI 0.87, 1.11), adult-onset IBD risk was increased (aHR 1.17, 95% CI 1.04, 1.31). This increase in risk was driven by UC (aHR 1.32, 95% CI 1.12, 1.55), but not Crohn's disease (1.03, 95% CI 0.87, 1.22).

DISCUSSION

Early-life mebendazole exposure is associated with an increase in the risk of adult-onset UC. These findings suggest the importance of early-life exposures in shaping the risk of IBD later in life.

Tumor grade and symptoms at presentation are survival risk factors in Chinese patients with primary retroperitoneal sarcoma

Background and Aim

No cohort studies have been performed on Chinese primary retroperitoneal sarcoma (RPS) patients. Data derived from western cohort studies may not be directly superimposable on Asian counterparts. Furthermore, the risk factors for survival of RPS are currently unknown for Chinese patients. The objectives were therefore to (1) gain insight into RPS incidence and patient demographics and clinical details; (2) determine the risk factors for overall survival (OS) and disease-free survival (DFS); and (3) critically appraise the Asian cohort data in relation to information obtained in western cohort studies.

Methods

In this retrospective cohort study, the health records of patients that had been diagnosed with primary localized RPS with curative intent between 2009 and 2020 were analyzed. Cox proportional hazards analysis was conducted to evaluate the risk factors for OS and DFS.

Results

A total of 261 patients met the inclusion criteria. Ninety-six (36.8%) patients had been diagnosed with well-differentiated liposarcoma, 63 patients (24.1%) with dedifferentiated liposarcoma, 41 patients (15.7%) with leiomyosarcoma (LMS), 22 patients (8.4%) with solitary fibroma, 7 patients (2.7%) with malignant peripheral nerve sheath tumor (MPNST), and 32 patients (12.3%) with another type of RPS. The study further revealed that (1) the 5-y OS and DFS in RPS patients was 67.8% and 51.3%, respectively, with the highest OS and DFS observed in MPNST (100% and 100%, respectively) and the lowest 5-y OS and DFS attributed to LMS (42.6% and 28.9%, respectively); (2) symptoms at presentation, Federal National Cancer Center (FNCLCC) grade, and number of combined resections are independent risk factors in OS; (3) symptoms at presentation, FNCLCC grade, chemotherapy, and hospital length of stay are independent risk factors for DFS; and (4) patients at high risk (symptoms at presentation and high-grade tumors) have less than half the chance of survival at 5 y post-diagnosis than patients with a low-risk profile.

Conclusions

Symptoms at presentation constitute a risk factor for OS and DFS. When combined with tumor grade - another risk factor for both OS and DFS - patients can be classified into a high-risk and low-risk category to gauge a patient's prognosis and, accordingly, frame an optimal clinical trajectory. Moreover, the clinicopathology and overall prognosis of RPS in Asian and Western populations are comparable and hence superimposable.

Relevance for Patients

The present study identifies the risk factors of survival in RPS and suggests symptoms at presentation should be considered in the preoperative consultation and added in prognostic grouping.

A robust hazard ratio for general modeling of survival-times

Hazard ratios (HR) associated with the well-known proportional hazard Cox regression models are routinely used for measuring the impact of one factor of interest on a time-to-event outcome. However, if the underlying real model does not fit with the theoretical requirements, the interpretation of those HRs is not clear. We propose a new index, gHR, which generalizes the HR beyond the underlying survival model. We consider the case in which the study factor is a binary variable and we are interested in both the unadjusted and adjusted effect of this factor on a time-to-event variable, potentially, observed in a right-censored scenario. We propose non-parametric estimations for unadjusted gHR and semi-parametric regression-induced techniques for the adjusted case. The behavior of those estimators is studied in both large and finite sample situations. Monte Carlo simulations reveal that both estimators provide good approximations of their respective inferential targets. Data from the Health and Lifestyle Study are used for studying the relationship of the tobacco use and the age of death and illustrate the practical application of the proposed technique. gHR is a promising index which can help facilitate better understanding of the association of one study factor on a time-dependent outcome.

Mortality Associated with Healthy Eating Index Components and an Empirical-Scores Healthy Eating Index in a Cohort of Postmenopausal Women

BACKGROUND

Studies of diet and chronic disease include a recent important focus on dietary patterns. Patterns are typically defined by listing dietary variables and by totaling scores that reflect whether consumption is encouraged or discouraged for listed variables. However, precision may be improved by including total energy consumption among the dietary variables and by scoring dietary variables empirically.

OBJECTIVES

To relate Healthy Eating Index (HEI)-2010 components and total energy intake to all-cause and cause-specific mortality in Women's Health Initiative (WHI) cohorts and to define and evaluate an associated Empirical-Scores Healthy Eating Index (E-HEI).

METHODS

Analyses are conducted in WHI cohorts (n = 67,247) of healthy postmenopausal women, aged 50-79 y, when enrolled during 1993-1998 at 40 US clinical centers, with embedded nutrition biomarker studies. Replicate food-frequency assessments for HEI-2010 ratio variables and doubly labeled water total energy assessments, separated by ∼6 mo, are used as response variables to jointly calibrate baseline dietary data to reduce measurement error influences, using 2 nutrition biomarker studies (n = 199). Calibrated dietary variables are associated with mortality risk, and an E-HEI is defined, using cross-validated HR regression estimation.

RESULTS

Of 15 dietary variables considered, all but empty calories calibrated well. Ten variables related significantly (P < 0.05) to total mortality, with favorable fruit, vegetable, whole grain, refined grain, and unsaturated fat associations and unfavorable sodium, saturated fat, and total energy associations. The E-HEI had cross-validated total mortality HRs (95% CIs) of 0.87 (0.82, 0.93), 0.80 (0.76, 0.86), 0.77 (0.72, 0.82), and 0.74 (0.69, 0.79) respectively, for quintiles 2 through 5 compared with quintile 1. These depart more strongly from the null than do HRs for HEI-2010 quintiles, primarily because of total energy.

CONCLUSIONS

Mortality among US postmenopausal women depends strongly on diet, as evidenced by a new E-HEI that differs substantially from earlier dietary pattern score specifications.

COVID-19 Diagnosis and Risk of Death Among Adults With Cancer in Indiana: Retrospective Cohort Study

BACKGROUND

Prior studies, generally conducted at single centers with small sample sizes, found that individuals with cancer experience more severe outcomes due to COVID-19, caused by SARS-CoV-2 infection. Although early examinations revealed greater risk of severe outcomes for patients with cancer, the magnitude of the increased risk remains unclear. Furthermore, prior studies were not typically performed using population-level data, especially those in the United States. Given robust prevention measures (eg, vaccines) are available for populations, examining the increased risk of patients with cancer due to SARS-CoV-2 infection using robust population-level analyses of electronic medical records is warranted.

OBJECTIVE

The aim of this paper is to evaluate the association between SARS-CoV-2 infection and all-cause mortality among recently diagnosed adults with cancer.

METHODS

We conducted a retrospective cohort study of newly diagnosed adults with cancer between January 1, 2019, and December 31, 2020, using electronic health records linked to a statewide SARS-CoV-2 testing database. The primary outcome was all-cause mortality. We used the Kaplan-Meier estimator to estimate survival during the COVID-19 period (January 15, 2020, to December 31, 2020). We further modeled SARS-CoV-2 infection as a time-dependent exposure (immortal time bias) in a multivariable Cox proportional hazards model adjusting for clinical and demographic variables to estimate the hazard ratios (HRs) among newly diagnosed adults with cancer. Sensitivity analyses were conducted using the above methods among individuals with cancer-staging information.

RESULTS

During the study period, 41,924 adults were identified with newly diagnosed cancer, of which 2894 (6.9%) tested positive for SARS-CoV-2. The population consisted of White (n=32,867, 78.4%), Black (n=2671, 6.4%), Hispanic (n=832, 2.0%), and other (n=5554, 13.2%) racial backgrounds, with both male (n=21,354, 50.9%) and female (n=20,570, 49.1%) individuals. In the COVID-19 period analysis, after adjusting for age, sex, race or ethnicity, comorbidities, cancer type, and region, the risk of death increased by 91% (adjusted HR 1.91; 95% CI 1.76-2.09) compared to the pre-COVID-19 period (January 1, 2019, to January 14, 2020) after adjusting for other covariates. In the adjusted time-dependent analysis, SARS-CoV-2 infection was associated with an increase in all-cause mortality (adjusted HR 6.91; 95% CI 6.06-7.89). Mortality increased 2.5 times among adults aged 65 years and older (adjusted HR 2.74; 95% CI 2.26-3.31) compared to adults 18-44 years old, among male (adjusted HR 1.23; 95% CI 1.14-1.32) compared to female individuals, and those with ≥2 chronic conditions (adjusted HR 2.12; 95% CI 1.94-2.31) compared to those with no comorbidities. Risk of mortality was 9% higher in the rural population (adjusted HR 1.09; 95% CI 1.01-1.18) compared to adult urban residents.

CONCLUSIONS

The findings highlight increased risk of death is associated with SARS-CoV-2 infection among patients with a recent diagnosis of cancer. Elevated risk underscores the importance of adhering to social distancing, mask adherence, vaccination, and regular testing among the adult cancer population.

Survival and epidemiology of amyotrophic lateral sclerosis (ALS) cases in the Chicago and Detroit metropolitan cohort: incident cases 2009-2011 and survival through 2018

Amyotrophic lateral sclerosis (ALS) is a fatal, progressive neurodegenerative disorder. The National ALS Registry launched surveillance projects to understand the distribution of ALS in targeted geographic cohorts. Objective: To describe the demographics, incidence, and survival of persons with ALS (PALS) identified in the Chicago and Detroit area population-based cohort. Methods: Neurologists in the catchment area provided case reports for eligible ALS cases diagnosed and/or cared for from 1 January 2009 through 31 December 2011. Crude incidence rates were calculated for 2009-2011 and stratified by race and ethnicity. Using data from the National Death Index through 2018, we modeled the effect of patient covariates on mortality using the Cox proportional hazard regression. Results: Of the 574 cases, 372 (64.8%) were diagnosed from 2009 to 2011. The combined crude incidence rates for 2009, 2010, and 2011 were 1.44, 1.53, and 1.73 cases per 100,000 person-years, respectively. Of the 486 subjects with complete survival data, 81% were deceased at the end of follow-up. Median survival time was 2.2 years, with 30% and 9% of subjects surviving past 5 and 10 years after diagnosis, respectively. Additionally, female PALS and PALS with longer time between symptom onset and diagnosis experienced longer survival. Nonwhites also experienced longer survival than Whites, except for those cases diagnosed in the younger age categories. Conclusion: Understanding the survival of ALS patients can aid in understanding variable prognostic factors, which can potentially extend survival and improve disease management.

Hazard Ratio and Hazard Index as Preliminary Estimators Associated to the Presence of Furans and Alkylfurans in Belgian Foodstuffs

This paper provides an estimation of the hazard related to the presence of furan and five alkyl furans (2- and 3-methylfuran, 2-ethylfuran, 2,5- and 2,3-dimethylfuran) in foodstuffs available in the Belgian market. To achieve this objective, a specific sampling plan was designed to ensure that the samples collected (n = 1003) represent the diversity of the Belgian food chain. Herein, the concepts of the Hazard Ratio of a sample (HRs) and the Hazard Index of a sample (HIs) were introduced to primarily characterize the hazard related to the co-occurrence of these compounds. The HRs was measured as the ratio of the potential daily exposure to a substance (expressed in mg/Kg of food) to both the 10% reference dose level for chronic effects (expressed in mg/(kg b.w*day)) and the human standard weight (expressed in kg). Whereas the HIs is the sum of the HRs of compounds that affect the same target organ/system, a hazard index greater than one indicates a highly contaminated matrix that could induce a hazard. It is an alarm indicating that additional attention should be given to this matrix. This may involve additional analyses to confirm the high level, to identify sources, etc. It is also an alarm for the risk assessor to be very careful with flagged matrices and to avoid combination with other matrices. The HIs highlight a relatively low concern for all foods analyzed (HI median < 1.0) with a relatively higher suspected hazard for coffee drinks (HI median = 0.068, HI max = 0.57). This preliminary estimation of the potential hazard suggests that coffee beverages should be examined in more detail in a full risk assessment and that coffee consumption should be taken with caution given the levels of furan and alkylfurans reported in this study.

Risk Associations between Vehicular Traffic Noise Exposure and Cardiovascular Diseases: A Residential Retrospective Cohort Study

Environmental noise can induce detrimental health effects such as cardiovascular disease (CVD). The relationship between vehicular traffic noise pollution and CVD was investigated through a retrospective residential cohort study in the city of Pisa. Four exposure classes were defined for noise pollution, using noise propagation maps. The association between noise exposures and cause-specific mortality or hospitalization of the subjects of the cohort was calculated using the hazard ratio (HR) for night and day through a multiple time-dependent and sex-specific Cox regression adjusting for age, the socio-economic deprivation index, and traffic air pollution. Mortality excess for CVD and risk trends for a 1 decibel noise increment were observed among the most exposed women (mortality: HRnight_class4 1.15 (1.03-1.28); Trend_night 1.007 (1.002-1.012); HRday_class4 1.14 (1.02-1.27); Trend_day 1.008 (1.003-1.013)), particularly for ischaemic disease (mortality: Trend_night 1.008 (0.999-1.017); Trend_day 1.009 (0.999-1.018)) and cerebrovascular disease (mortality: HRnight_class3 1.23 (1.02-1.48), HRday_class3 1.24 (1.03-1.49)). Hospitalization analyses confirm mortality results. A decreased risk for hospitalization was also observed among the most exposed men (HRday_class4 0.94 (0.88-1.01), particularly for ischaemic disease (HRnight_class4 0.90 (0.80-1.02); HRday_class4 0.86 (0.77-0.97)) and cerebrovascular disease (HRnight_class4 0.89 (0.78-1.01)). Authors recommend the adoption of prevention measures aimed at mitigating noise and the activation of a monitoring of the risk profile in the Pisa population updating both the residential cohort and health data.

Trends in marginal lung allograft survival: advanced-age donors improve

INTRODUCTION

Although lung demand continues to outpace supply, 75% of potential donor lungs are discarded without being transplanted in the United States. To identify the discarded cohorts best suited to alleviate the lung shortage and reduce waitlist mortality, we explored changes in survival over time for five marginal donor definitions: age >60 years, smoking history >20 pack-years, PaO2/FiO2 <300mmHg, purulent bronchoscopic secretions, and chest radiograph infiltrates.

METHODS

Our retrospective cohort study separated 27,803 lung recipients in the UNOS Database into three 5-year eras by transplant date: 2005-2009, 2010-2014, and 2015-2019. Multivariable Cox proportional hazards regression and Kaplan-Meier analysis with log-rank test were used to compare survival across the eras.

RESULTS

Three definitions-low PaO 2/FiO 2, purulent bronchoscopic secretions, and abnormal chest radiographs-did not bear out as truly marginal, demonstrating lack of significantly elevated risk. Advanced donor age demonstrated considerable survival improvement (HR (95% CI): 1.47 (1.26-1.72) in 2005-2009 down to 1.14 (0.97-1.35) for 2015-2019), with protective factors being recipients <60 years, moderate recipient BMI, and low Lung Allocation Score. Donors with smoking history failed to demonstrate any significant improvement (HR (95% CI): 1.09 (1.01-1.17) in 2005-2009 increasing to 1.22 (1.08-1.38) in 2015-2019).

CONCLUSIONS

Advanced donor age, previously the most significant risk factor, has improved to near- benchmark levels, demonstrating the possibility for matching older donors to healthier non-elderly recipients in selected circumstances. Low PaO 2/FiO 2, bronchoscopic secretions, and abnormal radiographs demonstrated survival on par with standard donors. Significant donor smoking history, a moderate risk factor, has failed to improve. This article is protected by copyright. All rights reserved.

Risk factors associated with mortality in hypersensitivity pneumonitis: a meta-analysis

BACKGROUND

Hypersensitivity pneumonitis (HP) related deaths have increased substantially in recent years. It is important to identify the risk factors of HP significantly associated with mortality to ensure close patient monitoring and assess disease progression.

RESEARCH DESIGN AND METHODS

Extensive literature search was conducted in accordance with the PRISMA checklist. Literature search of PUBMED, EMBASE and Cochrane Library database between January 2009 and April 2021 using the terms "hypersensitivity pneumonitis", "hazard ratio", and "mortality" identified 325 articles. A total of 22 independent original studies focusing on mortality of HP patients were assessed.

RESULTS

This systematic review and meta-analysis suggests that increased age, male sex, honeycombing and traction bronchiectasis patterns on high-resolution computed tomography (HRCT) images are the major mortality-related risk factors of patients with HP. In case of chronic HP, antigen exposure appeared to be an additional risk factor.

CONCLUSIONS

The clinico-radiological risk factors of mortality identified for HP will enable effective and close monitoring of patients, prognostication and guide towards appropriate management decisions. However, association between the type of antigen and mortality remains to be explored.

Potential Cancer Risk in Patients with Rheumatoid Arthritis: A Longitudinal Korean Population-Based Analysis

The potential link between rheumatoid arthritis (RA) and cancer incidence needs to be validated due to inconsistent results between Asian and Western countries. We explored the long-term association of RA with the overall and organ-specific cancer incidence using nationwide population data. This longitudinal follow-up study (2002–2015) included 3070 patients with RA and 12,280 controls (1:4 propensity score-matched for sex, age, residence, and income) from the Korean National Health Insurance Service-Health Screening Cohort database. A Cox proportional hazard model estimated the hazard ratio for malignancy following adjusting for covariates. Despite the similar overall cancer incidence between RA and control groups, differences in the incidence of organ-specific cancers were noted: the RA group had a 1.63-fold greater likelihood for lung cancer (95% confidence interval 1.11–2.40). In the sex-stratified subgroup analyses, the male RA patients exhibited higher odds of lung and thyroid cancer but a lower probability for colorectal cancer; no such associations were detected in either female patients with RA or age subgroups. In summary, the higher likelihood for lung cancer in Korean RA patients, especially thyroid and lung cancer in male RA patients, seems to be characteristic, which needs to be carefully monitored.

Effects of Emergency Duties on Cardiovascular Diseases in Firefighters: A 13-Year Retrospective Cohort Study

OBJECTIVES

This study aimed to examine the effects of firefighters' emergency duties on the incidence of cardiovascular disease (CVD).

METHODS

We used a 13-year follow-up in a nationwide retrospective cohort study. A total of 363,137 employees were recruited. The sex-and age-specific incidence of CVD (hypertension, angina pectoris, and acutemyocardial infarction [AMI]) in firefighters and public officials was estimated.

RESULTS

The overall age-specific sex-based incidence of CVD, except for hypertension, was higher in firefighters than in public officials. The age-stratified hazard ratios for the three types of CVD in male firefighters were also higher. AMI was more common in younger firefighters, whereas angina pectoris and hypertension were common in older firefighters.

CONCLUSIONS

Firefighters' duties are more likely to increase the risk of CVD, and preventive strategies with proven benefits are required.

Association of Daily Eating Duration and Day-To-Day Variability in the Timing of Eating With Fatal Cancer Risk in Older Men

Meal timing has significant effects on health. However, whether meal timing is associated with the risk of developing and dying of cancer is not well-researched in humans. In the present study, we used data from 941 community-dwelling men aged 71 years who participated in the Uppsala Longitudinal Study of Adult Men to examine the association of meal timing with cancer morbidity and fatal cancer. The following meal timing variables were derived from 7-day food diaries: (i) daily eating duration, i.e., the time between the first and last eating episode of an arbitrary day; (ii) the calorically weighted midpoint of the daily eating interval, a proxy of when the eating window typically occurs during an arbitrary day; and (iii) the day-to-day variability in the timing of eating. We also assessed the reported daily energy intake reliability using the Goldberg method. During a mean observational period of 13.4 years, 277 men (29.4%) were diagnosed with cancer. Furthermore, 191 men (20%) died from cancer during 14.7 years of follow-up. As shown by Cox regression adjusted for potential confounders (e.g., smoking status and daily energy intake), men with reliable dietary reports whose daily eating intervals were on average 13 h long had a 2.3-fold greater fatal cancer risk than men whose daily eating windows were on average about 11 h long. We also found that men with an average day-to-day variability in the timing of eating of 48 to 74 min had a 2- to 2.2-fold higher fatal cancer risk than those with the lowest average day-to-day variability in the timing of eating (i.e., 23 min). No clear associations were found in men with inadequate dietary reports, emphasizing the need to consider the reliability of dietary records in nutritional epidemiology. To fully unlock its potential, studies are needed to test whether recommendations to time-restrict the 24-h eating interval and reduce day-to-day variability in the timing of eating can meaningfully alter the risk of death due to cancer.