Resilience and associated factors in orphaned and separated adolescents in Kenya: Understanding the relationship with care environment and HIV risks

Orphans are at higher risk of HIV infection and several important HIV risk factors than non-orphans; however, this may be due to a combination of related social, psychological, and economic factors, as well as care environment, rather than orphan status alone. Understanding these complex relationships may aid policy makers in supporting evidence-based, cost-effective programming for this vulnerable population. This longitudinal study uses a causal effect model to examine, through decomposition, the relationship between care environment and HIV risk factors in orphaned and separated adolescents and youths (OSAY) in Uasin Gishu County, Kenya; considering resilience, social, peer, or family support, volunteering, or having one's material needs met as potential mediators. We analysed survey responses from 1105 OSAY age 10-26 living in Charitable Children's Institutions (CCI) (orphanages) and family-based care settings (FBS). Follow-up time was 7-36 months. Care in CCIs (vs. FBS) was associated with a decreased likelihood of engaging in forced, exchange, and consensual sex. Excess relative risks (ERR) attributable to the indirect pathway, mediation, or interaction were not significant in any model. Care environment was not statistically associated with differences in substance use. Our findings support the direct, unmediated, association between institutional care and HIV risk factors.

An interrupted time series evaluation of the effect of cannabis legalization on intentional self-harm in two Canadian provinces: Ontario and Alberta

INTRODUCTION

Despite the association between cannabis use and higher prevalence of suicidal ideation and attempt, the effect of cannabis legalization and regulation in Canada on intentional self-harm has not been determined.

METHODS

We used an interrupted time series of population-based rates of emergency department (ED) visits and hospitalizations for intentional self-harm per 100 000 in Ontario and Alberta from January/April 2010 to February 2020. Aggregate monthly counts of ED visits and hospitalizations for intentional self-harm (ICD-10 codes X60-X84, R45.8) were obtained from the National Ambulatory Care Reporting System and Discharge Abstract Database, respectively.

RESULTS

The legalization and regulation of cannabis in Canada was not significantly associated with a change in rates of ED visits for intentional self-harm in Ontario (level = 0.58, 95% CI: -1.14 to 2.31; trend = -0.17, 95% CI: -0.35 to 0.01) or Alberta (level = -0.06, 95% CI: -2.25 to 2.12; trend = -0.07, 95% CI: -0.27 to 0.13). Hospitalizations for intentional self-harm also remained unchanged in Ontario (level = -0.14, 95% CI: -0.48 to 0.20; trend = 0.01, 95% CI: -0.03 to 0.04) and Alberta (level = -0.41, 95% CI: -1.03 to 0.21; trend = -0.03, 95% CI: -0.08 to 0.03).

CONCLUSION

Legalization and regulation of cannabis in Canada has not increased rates of ED visits or hospitalizations for intentional self-harm in Ontario and Alberta. Individual-level analyses that account for demographic characteristics and include other provinces and territories are needed.

The effect of recreational cannabis legalization and commercialization on substance use, mental health, and injury: a systematic review

OBJECTIVE

To determine the effect of recreational cannabis legalization (RCL) and/or recreational cannabis commercialization (RCC) on emergency department (ED) visits, hospitalizations, and deaths due to substance use, injury, and mental health among those aged 11 years and older.

METHODS

A systematic review of six electronic databases up to February 1, 2023. Original, peer-reviewed articles with interrupted time series or before and after designs were included. Four independent reviewers screened articles and assessed risk of bias. Outcomes with 'critical' risk of bias were excluded. Protocol registered on PROSPERO (# CRD42021265183).

RESULTS

After screening and risk of bias assessment, 29 studies were included which examined ED visits or hospitalizations for cannabis use or alcohol (N = 10), opioid mortality (N = 3), motor vehicle fatalities or injury (N = 11), and intentional injury/mental health (N = 5). Rates or number of cannabis-related hospitalizations increased after RCL in Canada and the USA. Immediate increases in rates of cannabis-related ED visits were found after both RCL and RCC in Canada. Rates of traffic fatalities increased after RCL and RCC in certain jurisdictions in the USA.

CONCLUSIONS

RCL was associated with increased rates of cannabis-related hospitalizations. RCL and/or RCC was associated with increased rates of cannabis-related ED visits, consistently shown across sex and age groups. The effect on fatal motor vehicle incidents was mixed, with observed increases found after RCL and/or RCC. The effect of RCL or RCC on opioids, alcohol, intentional injury, and mental health is not clear. These results inform population health initiatives and international jurisdictions considering RCL implementation.

Surgeon-level versus hospital-level quality variance in kidney cancer surgery

PURPOSE

To determine whether variance in kidney cancer surgery quality indicators (QIs) is most impacted by surgeon-level or hospital-level factors in order to inform quality improvement initiatives.

MATERIALS AND METHODS

The ICES and Veterans Affairs (VA) databases were queried for patients undergoing surgery for localized kidney cancer. Kidney cancer surgery QIs were defined within each cohort. Quality of care was benchmarked at a surgeon- vs. hospital-level to identify statistical outliers, using available clinicopathological data to adjust for differences in case-mix. Variance between surgeons and hospitals was calculated for each QI using a random-effects model.

RESULTS

The QI with the greatest amount of variance explained by hospital and surgeon-level factors was proportion of cases performed with minimally invasive surgery (MIS). The majority of this variance was due to surgeon-level factors for both the VA and ICES cohorts. The proportion of cases performed using an MIS approach was also the QI with the greatest number of outlier hospitals and surgeons compared to the average performance. The proportion of partial nephrectomies performed for patients at risk of chronic kidney disease was the QI with the greatest amount of variance due to hospital-level factors for the ICES cohort.

CONCLUSIONS

The proportion of localized kidney cancer cases performed using an MIS approach is the QI requiring the greatest attention. Quality improvement initiatives should focus on surgeon-level factors to increase the number of MIS cases being performed for patients with localized renal masses.

The effect of recreational cannabis legalization on rates of traffic injury in Canada

AIMS

To measure the impact of Canada's recreational cannabis legalization (RCL) in October 2018 and the subsequent impact of the COVID-19 lockdowns from March 2020 on rates of emergency department (ED) visits and hospitalizations for traffic injury.

DESIGN

An interrupted time series analysis of rates of ED visits and hospitalizations in Canada recorded in population-based databases from January/April 2010 to March 2021.

SETTING

ED visits in Ontario and Alberta and hospitalizations in Ontario, Alberta, British Columbia, Prairies [Manitoba, Saskatchewan], and Maritimes [Nova Scotia, New Brunswick, Newfoundland, Prince Edward Island]. Cases Monthly counts of presentations to the ED or hospital for motor vehicle injury or pedestrian/cyclist injury, used to calculate monthly rates per 100,000 population.

MEASUREMENTS

An occurrence of one or more International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Canada (ICD-10-CA) code for motor vehicle injury (V20-V29, V40-V79, V30-39, V86) and pedestrian/cyclist injury (V01-V09, V10-V19) within the National Ambulatory Care Reporting System and Discharge Abstract Database.

FINDINGS

There were no statistically significant changes in rates of ED visits and hospitalizations for motor vehicle or pedestrian/cyclist injury after RCL after accounting for multiple testing. After COVID-19, there was an immediate decrease in the rate of ED visits for motor vehicle injury that was statistically significant only in Ontario (level change ß = -16.07 in Ontario, 95% confidence interval [CI] -20.55 to -11.60, p=0.000; ß = -10.34 in Alberta, 95% CI -17.80 to -2.89, p=0.008; alpha of 0.004) and no changes in rates of hospitalizations.

CONCLUSIONS

Canada's recreational cannabis legalization (RCL) did not notably impact motor vehicle and pedestrian/cyclist injury. The rate of emergency department visits for motor vehicle injury decreased immediately after COVID-19, resulting in rates below post-RCL levels in the year after COVID-19.

Suboptimal oral health and the risk of cardiovascular disease in the presence of competing death: a data linkage analysis

OBJECTIVE

The objective of this study is to simultaneously assess the associations between suboptimal oral health (SOH) and cardiovascular disease (CVD) and competing death (CD).

METHODS

Ontario residents aged 40 years and over who participated in the Canadian Community Health Survey 2003 and 2007-2008 were followed until December 31, 2016 for the incidence of CVD or CD. SOH was assessed based on self-rated oral health and inability to chew. Multivariable competing risk analysis was adjusted for socioeconomic characteristics, behavioural factors and intermediate health outcomes.

RESULTS

The study sample included 36,176 participants. Over a median follow-up of 9.61 years, there were 2077 CVD events and 3180 CD events. The fully adjusted models indicate 35% (HR = 1.35, 95% CI: 1.12-1.64) increase in the risk of CVD and 57% (HR = 1.57, 95% CI: 1.33-1.85) increase in the risk of CD among those who reported poor oral health as compared to those who reported excellent oral health. The fully adjusted models also indicate 11% (HR = 1.11, 95% CI: 0.97-1.27) increase in the hazard of CVD and 37% (HR = 1.37, 95% CI: 1.24-1.52) increase in the hazard of CD among those who reported inability to chew.

CONCLUSION

This study provides important information to contextualize CVD risk among those with SOH. The competing risk analysis indicates that those with SOH may benefit from additional interventions to prevent CVD and CD. Accordingly, managing the risk of CVD among those with SOH should fall under a more comprehensive approach that aims at improving their overall health and well-being.

Emulating a target trial using primary care electronic health records: SGLT-2i medications and Hemoglobin A1c

Substantial effort has been dedicated to conducting randomized controlled experiments to generate clinical evidence for diabetes treatment. Randomized controlled experiments are the gold standard to establish cause and effect. However, due to their high-cost and time-commitment, large observational databases such as those comprised of electronic health record (EHR) data collected in routine primary care may provide an alternative source to address such causal objectives. We used a Canadian primary care repository housed at University of Toronto to emulate a randomized experiment. We estimated the effectiveness of sodium-glucose co-transporter 2 inhibitors (SGLT-2i) medications for patients with diabetes using Hemoglobin A1c (HbA1c) as a primary outcome and marker for glycemic control from 2018 to 2021. We assumed an intention-to-treat analysis for prescribed treatment, with analyses based on the treatment assigned rather than the treatment eventually received. We defined the causal contrast of interest as the net change in HbA1c (%) between the group receiving standard of care versus the group receiving SGLT-2i medications. Using a counterfactual framework, marginal structural models demonstrated a reduction in mean HbA1c with theinitiation of SGLT-2i medications. These findings provided similar effect sizes to those from earlier clinical trials on assessing the effectiveness of SGLT-2i medications.

Influence of previous experience with and beliefs regarding anal cancer screening on willingness to be screened among men living with HIV

BACKGROUND

Implementation of anal cancer screening requires the procedure to be acceptable to the target population. Our objective was to assess the beliefs of men living with HIV regarding anal cancer screening and identify factors associated with their willingness to participate in screening.

METHODS

We developed a cross-sectional questionnaire using the Theory of Planned Behavior to examine beliefs regarding prevention of human papillomavirus (HPV)-related diseases, administered to men living with HIV in 2016-2017 in a multi-site HIV clinical cohort. Correspondence analysis was used to examine the interrelationships between men's beliefs and willingness to undergo anal cancer screening. We used multivariable proportional odds models to identify factors associated with increasing willingness. Results were reported as adjusted odds ratios (aOR) with 95% confidence intervals (CI).

RESULTS

Among 1677 male participants, the vast majority (90%) would be willing to undergo screening by "anal Pap test"; willingness clustered with positive beliefs (e.g. confident they can get screened; disagree that they will feel pain) in the correspondence analysis. Higher self-perceived risk for anal cancer and positive beliefs regarding screening were associated with higher willingness to be screened. Gay, bisexual and other men who have sex with men had higher willingness (aOR = 1.62; 95% CI: 1.15, 2.29) than heterosexual men. Racialized men reported lower willingness (aOR = 0.68; 95% CI: 0.54, 0.89) than white men.

CONCLUSIONS

Men generally had positive beliefs and were willing to undergo screening, though there were differences by sexual orientation and racial identity. Tailored community-led initiatives could focus on men's understanding of their risk and expectations of anal cancer screening to facilitate participation.

Using scenario videos with Theatre Testing method to adapt a peer navigation model to improve street-connected youth's access to HIV care in Kenya and Canada

Theatre testing (TT) method demonstrates whole or portions of an evidence-based intervention to stakeholders to elicit feedback on context-specific adaptations and future implementation. The Peer Navigator Project (PNP) studied the adaptation and implementation of Peer Navigators in five urban sites to increase street-connected youth (SCY) access to HIV prevention, testing, and treatment in Canada and Kenya. TT was used with SCY, healthcare providers, and community stakeholders to collect feedback on the optimal characteristics of the PNs (e.g., social identities) and their professional activities and responsibilities in each site. Sites scripted unique scenarios of PNs supporting SCY and interacting with social service providers. Local actors were employed, and the scenarios were filmed and edited into videos alongside audience discussion questions. Videos were screened to separate audiences of SCY (n = 40), healthcare providers (n = 12), and community stakeholders (n = 59). Facilitated discussion about the scenarios were recorded as data, and transcripts were analyzed thematically by the research team. The scenario videos are presented as a unique adaptation to the TT method. The adaptations were time-consuming and limited the ability to present responsive changes while presenting the method to different audiences. They were also effective at maintaining presentation fidelity and eliciting diverse and meaningful responses from different stakeholder groups. One site successfully adapted the method for use in a physically distanced manner that complied with COVID-19 public health regulations. TT using video scenarios is an engaging approach that garners rich responses from diverse stakeholder groups about the adaptation of evidence-based interventions preparing for implementation in international settings.

Targeted L1-Regularization and Joint Modeling of Neural Networks for Causal Inference

The calculation of the Augmented Inverse Probability Weighting (AIPW) estimator of the Average Treatment Effect (ATE) is carried out in two steps, where in the first step, the treatment and outcome are modeled, and in the second step, the predictions are inserted into the AIPW estimator. The model misspecification in the first step has led researchers to utilize Machine Learning algorithms instead of parametric algorithms. However, the existence of strong confounders and/or Instrumental Variables (IVs) can lead the complex ML algorithms to provide perfect predictions for the treatment model which can violate the positivity assumption and elevate the variance of AIPW estimators. Thus the complexity of ML algorithms must be controlled to avoid perfect predictions for the treatment model while still learning the relationship between the confounders and the treatment and outcome. We use two NN architectures with an L1-regularization on specific NN parameters and investigate how their certain hyperparameters should be tuned in the presence of confounders and IVs to achieve a low bias-variance tradeoff for ATE estimators such as AIPW estimator. Through simulation results, we will provide recommendations as to how NNs can be employed for ATE estimation.

Marginal structural models using calibrated weights with SuperLearner: application to longitudinal diabetes cohort

Although machine learning has permeated many disciplines, the convergence of causal methods and machine learning remains sparse in the existing literature. Our aim was to formulate a marginal structural model in which we envisioned hypothetical (i.e. counterfactual) dynamic treatment regimes using a combination of drug therapies to manage diabetes: metformin, sulfonylurea and SGLT-2. We were interested in estimating “diabetes care provision” in next calendar year using a composite measure of chronic disease prevention and screening elements. We demonstrated the application of dynamic treatment regimes using the National Diabetes Action Canada Repository in which we applied a collection of mainstream statistical learning algorithms. We generated an ensemble of statistical learning algorithms using the SuperLearner based on the following base learners: (i) least absolute shrinkage and selection operator, (ii) ridge regression, (iii) elastic net, (iv) random forest, (v) gradient boosting machines, (vi) neural network. Each statistical learning algorithm was fitted using the pseudo-population with respect to the marginalization of the time-dependent confounding process. The covariate balance was assessed using the longitudinal (i.e. cumulative-time product) stabilized weights with calibrated restrictions. Our results indicated that the treatment drop-in cohorts (with respect to metformin, sulfonylurea and SGLT-2) may improve diabetes care provision in relation to treatment naïve cohort. As a clinical utility, we hope that this article will facilitate discussions around the prevention of adverse chronic outcomes associated with diabetes through the improvement of diabetes care provisions in primary care.

Marginal structural models using calibrated weights with SuperLearner: application to type II diabetes cohort

As different scientific disciplines begin to converge on machine learning for causal inference, we demonstrate the application of machine learning algorithms in the context of longitudinal causal estimation using electronic health records. Our aim is to formulate a marginal structural model for estimating diabetes care provisions in which we envisioned hypothetical (i.e. counterfactual) dynamic treatment regimes using a combination of drug therapies to manage diabetes: metformin, sulfonylurea and SGLT-2i. The binary outcome of diabetes care provisions was defined using a composite measure of chronic disease prevention and screening elements [27] including (i) primary care visit, (ii) blood pressure, (iii) weight, (iv) hemoglobin A1c, (v) lipid, (vi) ACR, (vii) eGFR and (viii) statin medication. We used several statistical learning algorithms to describe causal relationships between the prescription of three common classes of diabetes medications and quality of diabetes care using the electronic health records contained in National Diabetes Repository. In particular, we generated an ensemble of statistical learning algorithms using the SuperLearner framework based on the following base learners: (i) least absolute shrinkage and selection operator, (ii) ridge regression, (iii) elastic net, (iv) random forest, (v) gradient boosting machines, and (vi) neural network. Each statistical learning algorithm was fitted using the pseudo-population generated from the marginalization of the time-dependent confounding process. Covariate balance was assessed using the longitudinal (i.e. cumulative-time product) stabilized weights with calibrated restrictions. Our results indicated that the treatment drop-in cohorts (with respect to metformin, sulfonylurea and SGLT-2i) may have improved diabetes care provisions in relation to treatment naive (i.e. no treatment) cohort. As a clinical utility, we hope that this article will facilitate discussions around the prevention of adverse chronic outcomes associated with type II diabetes through the improvement of diabetes care provisions in primary care.

A Novel Metric for Hospital Quality in Kidney Cancer Surgery: A Veterans Affairs National Health System Validation of Concept

INTRODUCTION

We aimed to develop and validate a Compound Quality Score (CQS) as a metric for hospital-level quality of surgical care in kidney cancer at the Veterans Affairs National Health System.

METHODS

A retrospective review of 8,965 patients with kidney cancer treated at Veterans Affairs (2005-2015) was performed. Two previously validated process quality indicators (QIs) were explored: the proportion of patients with 1) T1a tumors undergoing partial nephrectomy and 2) T1-T2 tumors undergoing minimally invasive radical nephrectomy. Demographics/comorbidity/tumor characteristics/treatment year were used for case mix adjustments at hospital level. The predicted versus observed ratio of cases was calculated per hospital to generate QI scores using indirect standardization and multivariable regression models. CQS represents the sum of both scores. A total of 96 hospitals were grouped by CQS, and short-term patient-level outcomes were regressed on CQS levels to assess for length of stay (LOS), 30-day complications/readmission, 90-day mortality and total cost of surgical admission.

RESULTS

CQS identified 25/33/38 hospitals with higher/lower/average performance, respectively. High performance hospitals had higher nephrectomy volumes (p <0.01). Total CQS independently associated with LOS (β=-0.04, p <0.01, predicted LOS 0.84 days shorter for CQS=2 versus CQS=-2), 30-day surgical complications (OR=0.88, p <0.01) or 30-day medical complications (OR=0.93, p <0.01) and total cost of surgical admission (β =-0.014, p <0.01, predicted 12% lower cost for CQS=2 versus CQS=-2). No association was found between CQS and 30-day readmissions or 90-day mortality (all p >0.05), although low event rates were observed (8.9% and 1.7%, respectively).

CONCLUSIONS

Variability in quality of surgical care at hospital level can be captured with the CQS among patients with kidney cancer. CQS is associated with relevant short-term perioperative outcomes and surgical cost. QIs should be used to identify, audit and implement quality improvement strategies across health systems.

The relationships between resilience, care environment, and social-psychological factors in orphaned and separated adolescents in western Kenya

The relationships between care environment, resilience, and social factors in orphaned and separated adolescents and youths (OSAY) in western Kenya are complex and under-studied. This study examines these relationships through the analysis of survey responses from OSAY living in Charitable Children's Institutes (CCI) and family-based care settings (FBS) in Uasin Gishu County, Kenya. The associations between 1) care environment and resilience (measured using the 14-item Resilience Scale); 2) care environment and factors thought to promote resilience (e.g. social, family, and peer support); and 3) resilience and these same resilience-promoting factors, were examined using multivariable linear and logistic regressions. This cross-sectional study included 1202 OSAY (50.4% female) aged 10-26 (mean=16; SD=3.5). The mean resilience score in CCIs was 71 (95%CI=69-73) vs. 64 (95%CI=62-66) in FBS. OSAY in CCIs had higher resilience (β=7.67; 95%CI=5.26-10.09), social support (β=0.26; 95%CI=0.14-0.37), and peer support (β=0.90; 95%CI=0.64-1.17) than those in FBS. OSAY in CCIs were more likely to volunteer than those in FBS (OR=3.72; 95%CI=1.80-7.68), except in the male subgroup. Family (β=0.42; 95%CI=0.24-0.60), social (β=4.19; 95%CI=2.53-5.85), and peer (β=2.13; 95%CI=1.44-2.83) relationships were positively associated with resilience in all analyses. Volunteering was positively associated with resilience (β=5.85; 95%CI=1.51-10.19). The factor most strongly related to resilience in both fully adjusted models was peer support. This study found a strong relationship between care environment and resilience. Care environment and resilience each independently demonstrated strong relationships with peer support, social support, and participating in volunteer activities. Resilience also had a strong relationship with familial support. These data suggest that resilience can be developed through strategic supports to this vulnerable population.

Opioid Use after Nephrectomy for Kidney Cancer in Ontario: A Population-Based Study

OBJECTIVE

To compare the odds of early and prolonged post-operative opioid use in patients undergoing minimally invasive surgery (MIS) versus open surgery for nephrectomy.

METHODS

For opioid-naïve patients in Ontario who underwent nephrectomy for kidney cancer (1994-2017, n=7900), post-discharge opioid use was determined by prescriptions in the Ontario Drug Benefit database (age ≥65 years) and the Narcotics Monitoring System (all patients from 2012). Early opioid use was defined as ≥ 1 prescription 1-90 days after surgery. Two separate definitions of prolonged opioid use were examined: (1) prescription(s) for ≥ 60 days during post-operative days 90-365; (2) ≥ 1 prescriptions between both of: 1-90 days AND 91-180 days after surgery. Predictors of opioid use were assessed using multivariable generalized estimating equation logistic regression, accounting for surgeon clustering.

RESULTS

Overall, 67.4% of patients received early opioid prescriptions; however, prolonged use was low, ranging from 1.6 to 4.4% of patients depending on the definition. In multivariable analysis, open nephrectomy was associated with higher odds of early opioid use compared to MIS nephrectomy (Odds Ratio [OR] 1.36, 95% Confidence Interval [CI] 1.19-1.55). Surgery type was not significantly associated with prolonged opioid use for either definition (OR 1.22, CI 0.79 1.89 and OR 1.06, CI 0.83, 1.35).

CONCLUSIONS

In this population-level study of patients undergoing nephrectomy for kidney cancer, patients who received open surgery were at increased odds of receiving early post-operative opioids compared to MIS. Prolonged opioid use was low overall and was not significantly with associated with type of surgery.

Textbook Outcome and Survival in Patients With Gastric Cancer: An Analysis of the Population Registry of Esophageal and Stomach Tumours in Ontario (PRESTO)

OBJECTIVE

To examine the association between Textbook Outcome (TO)-a new composite quality measurement-and long-term survival in gastric cancer surgery.

BACKGROUND

Single-quality indicators do not sufficiently reflect the complex and multifaceted nature of perioperative care in patients with gastric adenocarcinoma.

METHODS

All patients undergoing gastrectomy for nonmetastatic gastric adenocarcinoma registered in the Population Registry of Esophageal and Stomach Tumours of Ontario (PRESTO) between 2004 and 2015 were included. TO was defined according to negative margins; >15 lymph nodes sampled; no severe complications; no re-interventions; no unplanned ICU admission; length of stay ≤21 days; no 30-day readmission; and no 30-day mortality. Three-year survival was estimated using the Kaplan-Meier method. A marginal multivariable Cox proportional-hazards model was used to estimate the association between achieving TO metrics and long-term survival. E-value methodology was used to assess for risk of residual confounding.

RESULTS

Of the 1836 patients included in this study, 402 (22%) achieved all TO metrics. TO patients had a higher 3-year survival rate compared to non-TO patients (75% vs 55%, log-rank P < 0.001). After adjustments for covariates and clustering within hospitals, TO was associated with a 41% reduction in mortality (adjusted hazards ratio 0.59, 95% confidence interval 0.48, 0.72, P < 0.001). These results were robust to potential residual confounding.

CONCLUSIONS

Achieving TO is strongly associated with improved long-term survival in gastric cancer patients and merits further focus in surgical quality improvement efforts.

The association of statin subgroups with lower urinary tract symptoms following a prostate biopsy

INTRODUCTION

This was a secondary analysis aiming to assess whether hydrophilic or hydrophobic statins have a differential effect on urinary retention (UR) and lower urinary tract symptoms (LUTS) in men following a prostate biopsy (PB), who were at risk for prostate cancer development.

METHODS

This was a population-based cohort study with data incorporated from the Institute for Clinical and Evaluative Sciences database to identify all Ontarian men aged 66 and above with a history of a single negative PB between 1994 and 2016, with no drug prescription history of any of several putative chemopreventative medications (statins, proton pump inhibitors, five-alpha-reductase inhibitors, and alpha-blockers). Multivariable Cox regression models with time-dependent covariates were used to assess the association of hydrophilic and hydrophobic statins with UR and LUTS within 30 days of a PB. All models were adjusted for other known putative chemopreventive medications, age, rurality, pharmacologically treated diabetes, comorbidity score, and study inclusion year.

RESULTS

Overall, 21 512 men were included, with a median followup time of 9.4 years (interquartile range [IQR] 5.4-13.4 years). Hydrophobic and hydrophilic statins were initiated by 30.7% and 19.6% of men, respectively, after the first negative PB. UR and LUTS were experienced by 2.2% and 10% of men, respectively. Cox models demonstrated hydrophilic statins were associated with a lower risk of UR (hazard ratio [HR] 0.56, 95% confidence interval [CI] 0.38-0.83, p=0.0038) and LUTS (HR 0.86, 95% CI 0.76-0.98, p=0.022), while no such association was shown for hydrophobic statins.

CONCLUSIONS

Initiation of hydrophilic statins in men older than 66 appears to be inversely associated with the risk of UR and LUTS within 30 days of a PB.

Instrumental variable estimation of early treatment effect in randomized screening trials

The primary analysis of randomized screening trials for cancer typically adheres to the intention-to-screen principle, measuring cancer-specific mortality reductions between screening and control arms. These mortality reductions result from a combination of the screening regimen, screening technology and the effect of the early, screening-induced, treatment. This motivates addressing these different aspects separately. Here we are interested in the causal effect of early versus delayed treatments on cancer mortality among the screening-detectable subgroup, which under certain assumptions is estimable from conventional randomized screening trial using instrumental variable type methods. To define the causal effect of interest, we formulate a simplified structural multi-state model for screening trials, based on a hypothetical intervention trial where screening detected individuals would be randomized into early versus delayed treatments. The cancer-specific mortality reductions after screening detection are quantified by a cause-specific hazard ratio. For this, we propose two estimators, based on an estimating equation and a likelihood expression. The methods extend existing instrumental variable methods for time-to-event and competing risks outcomes to time-dependent intermediate variables. Using the multi-state model as the basis of a data generating mechanism, we investigate the performance of the new estimators through simulation studies. In addition, we illustrate the proposed method in the context of CT screening for lung cancer using the US National Lung Screening Trial data.

Establishing a global quality of care benchmark report

BACKGROUND

The Movember funded TrueNTH Global Registry (TNGR) aims to improve care by collecting and analysing a consistent dataset to identify variation in disease management, benchmark care delivery in accordance with best practice guidelines and provide this information to those in a position to enact change. We discuss considerations of designing and implementing a quality of care report for TNGR.

METHODS

Eleven working group sessions were held prior to and as reports were being built with representation from clinicians, data managers and investigators contributing to TNGR. The aim of the meetings was to understand current data display approaches, share literature review findings and ideas for innovative approaches. Preferred displays were evaluated with two surveys (survey 1: 5 clinicians and 5 non-clinicians, 83% response rate; survey 2: 17 clinicians and 18 non-clinicians, 93% response rate).

RESULTS

Consensus on dashboard design and three data-display preferences were achieved. The dashboard comprised two performance summary charts; one summarising site's relative quality indicator (QI) performance and another to summarise data quality. Binary outcome QIs were presented as funnel plots. Patient-reported outcome measures of function score and the extent to which men were bothered by their symptoms were presented in bubble plots. Time series graphs were seen as providing important information to supplement funnel and bubble plots. R Markdown was selected as the software program principally because of its excellent analytic and graph display capacity, open source licensing model and the large global community sharing program code enhancements.

CONCLUSIONS

International collaboration in creating and maintaining clinical quality registries has allowed benchmarking of process and outcome measures on a large scale. A registry report system was developed with stakeholder engagement to produce dynamic reports that provide user-specific feedback to 132 participating sites across 13 countries.

Comparison of Joint and Landmark Modeling for Predicting Cancer Progression in Men With Castration-Resistant Prostate Cancer: A Secondary Post Hoc Analysis of the PREVAIL Randomized Clinical Trial

IMPORTANCE

Dynamic prediction models may help predict radiographic disease progression in advanced prostate cancer.

OBJECTIVE

To assess whether dynamic prediction models aid prognosis of radiographic progression risk, using ongoing longitudinal prostate-specific antigen (PSA) assessments.

DESIGN, SETTING, AND PARTICIPANTS

This prognostic study used data from the PREVAIL study to compare dynamic models for predicting disease progression. The PREVAIL study was a phase 3, multinational, double-blind, placebo-controlled randomized clinical trial of enzalutamide for prostate cancer conducted from September 2010 to September 2012. A total of 773 men with metastatic castration-resistant prostate cancer (CRPC) who had never received chemotherapy and had no baseline visceral disease were treated with enzalutamide. For illustration, 4 patients were selected based on PSA kinetics or PSA response in case studies. Data were analyzed from July 2018 to September 2019.

MAIN OUTCOMES AND MEASURES

Landmark and joint models were applied to dynamically predict radiographic progression-free survival (PFS) using longitudinal PSA profile, baseline PSA, lactate dehydrogenase, and hemoglobin levels. The main outcome was radiographic PFS as predicted using landmark and joint models. Current PSA and PSA change were considered longitudinal biomarkers possibly associated with radiographic PFS. Predictive performance was evaluated using Brier score for overall prediction errors (PEs) and area under the curve (AUC) for model discriminative capability. Case studies were illustrated using dynamic prediction plots.

RESULTS

A total of 763 men with metastatic CRPC treated with enzalutamide (mean [SD] age, 71.2 [8.5] years; mean [SD] body mass index [calculated as weight in kilograms divided by height in meters squared], 28.4 [4.6]) were included in the analysis. Current PSA and PSA change were associated with radiographic PFS in all models. Adding the PSA slope, compared with the landmark models using current PSA alone, improved the prediction of 5-month prospect of radiographic progression, with relative gains of 5.7% in prediction (PE [SE], 0.132 [0.008] vs 0.140 [0.008]) and 7.7% in discrimination (AUC [SE], 0.800 [0.018] vs 0.743 [0.018]) at month 10. In joint models with linear vs nonlinear PSA, prediction of 5-month risk of radiographic progression was improved when PSA trajectories were not assumed to be linear, with 8.0% relative gain in prediction (PE [SE], 0.150 [0.006] vs 0.138 [0.005]) and 19.4% relative gain in discrimination (AUC [SE], 0.653 [0.022] vs 0.780 [0.016]) at month 10. Predictions were affected by amount of marker information accumulated and prespecified assumptions. PSA changes affected progression risk more strongly at later vs earlier follow-up.

CONCLUSIONS AND RELEVANCE

This prognostic study found that prediction of radiographic PFS was improved when longitudinal PSA information was added to baseline variables. In a population of patients with metastatic CRPC, dynamic predictions using landmark or joint models may help identify patients at risk of progression.

Low human papillomavirus (HPV) knowledge related to low risk perception among men living with HIV: Implications for HPV-associated disease prevention

Human papillomavirus (HPV)-associated anal cancer is orders of magnitude higher among men living with HIV than the general male population. Our objective was to examine factors associated with HPV awareness and self-perceived risk for HPV-associated anal cancer among men living with HIV, which may influence uptake of cancer prevention strategies. A cross-sectional questionnaire on HPV was administered from 2016 to 2017 to 1677 men in a multisite, HIV clinical cohort in Ontario, Canada. We used logistic regression and proportional odds models to identify factors associated with being familiar with HPV and increasing self-perceived risk for anal cancer, respectively. We used correspondence analysis to examine associations of specific HPV-related knowledge with self-perceived risk. Only 52% were familiar with HPV, and 72% felt they had no or low risk for anal cancer. Familiarity with HPV was more common among men who have sex with men than heterosexual men (58% vs. 21%). Older men were less likely to be familiar with HPV (adjusted odds ratio [aOR] per 10 years = 0.77; 95% confidence interval [CI]: 0.69, 0.85). Familiarity with HPV was associated with increasing self-perceived risk (aOR = 2.39; 95% CI: 1.87, 3.04). After accounting for differences in HPV awareness and sexual orientation, racialized men had lower self-perceived risk (aOR = 0.68; 95% CI: 0.52, 0.88). In the correspondence analysis, risk-focused HPV-related knowledge (e.g., knowing smoking increases risk) was associated with highest risk perception. Efforts are needed to improve HPV-related health literacy in this population. Our findings suggest specific HPV-related knowledge may differentially influence self-perceived risk for anal cancer.

Reliability and validity of the RS14 in orphaned and separated adolescents and youths in western Kenya

PURPOSE

The 14-item Resilience Scale (RS14) is a tool designed to measure psychological resilience. It has been used effectively in diverse populations. However, its applicability is largely unknown for Sub-Saharan adolescent populations and completely unknown for orphaned and separated adolescents and youths (OSAY), a highly vulnerable population for whom resilience may be critical. This study assesses the RS14's psychometric properties for OSAY in Uasin Gishu County, Kenya.

METHODS

Survey responses from a representative sample of 1016 OSAY (51.3% female) aged 10-25 (mean = 16; SD = 3.5) living in institutional and home-based environments in Uasin Gishu County were analyzed. The RS14's psychometric properties were assessed by examining internal consistency reliability, confirmatory factor analyses, and convergent validity using correlations between resilience and each of social support and depression. Sub-analyses were conducted by age and sex.

RESULTS

Resilience scores ranged from 14-98 (mean = 66; SD = 19) with no sex-based significant difference. Resilience was higher for those aged ≥18 (mean = 69; range = 14-98) versus age <18 (mean = 65; range = 14-98). Internal consistency was good (Cronbach's α = .90). Confirmatory factor analysis indicated a 1-factor solution, though the model fit was only moderate. Resilience was positively correlated with social support in all ages (.22; p < .001) and negatively correlated with depression in individuals age <18 (-.22; p < .001). The relationship between resilience and depression in individuals age ≥18 was statistically significant only in females (-.17; p = .026).

CONCLUSION

This study demonstrates reasonable evidence that the RS14 is both valid and reliable for measuring psychological resilience in the population of OSAY in western Kenya.

Constructing inverse probability weights for institutional comparisons in healthcare

In comparing quality of care between hospitals, disease-specific quality indicators measure structural, process, or outcome elements related to the care of a particular condition. Such comparisons can be framed in terms of causal contrasts, answering the question of whether a patient (or a population of patients on average) would receive different care if treated at the care level of a different hospital. Fair comparisons have to be adjusted for patient case-mix, which is equivalent to controlling for confounding by the patient-level factors, including demographic factors, comorbidities, and disease progression. The methodological choice for such comparisons is usually between direct and indirect standardization methods. In this article, we discuss the alternative of inverse probability weighting as a tool for standardization in hospital comparisons. This involves fitting multinomial logistic hospital assignment models and using these to construct the inverse probability weights. The challenge in the present context is the presence of large number of hospitals being compared, many of which have a small patient volume. We propose methods to include small categories in the weighted analysis, as well as metrics and visualizations for checking the positivity/overlap and covariate balance in constructing such weights. The methods are illustrated in a running example using linked administrative data on surgical treatment of kidney cancer patients in Ontario.

A population-based study of fall-related traumatic brain injury identified in older adults in hospital emergency departments

OBJECTIVE

The purpose of this study was to examine the population-based trends and factors associated with hospitalization of patients with traumatic brain injury (TBI) treated in the Emergency Department (ED) among those 65 years and older. The implications of these trends for neurosurgery and the broader society are discussed.

METHOD

With a national, mandatory reporting system of ED visits, the authors used Poisson regression controlling for age and sex to analyze trends in fall-related TBI of those aged 65 years and older between 2002 and 2017.

RESULTS

The overall rate of ED visits for TBI increased by 78%—from 689.51 per 100,000 (95% CI 676.5–702.8) to 1229 per 100,000 (95% CI 1215–1243) between 2002 and 2017. Females consistently experienced higher rates of fall-related TBI than did males. All age groups 65 years and older experienced significant increases in fall-related TBI rate over the study period; however, the highest rates occurred among the oldest individuals (90+ and 85–89 years). The hospital admission rate increased with age and Charlson Comorbidity Index. Males experienced both a higher admission rate and a greater percentage change in admission rate than females.

CONCLUSIONS

Rates of ED visits for fall-related TBI, hospitalization, and in-ED mortality in those aged 65 years and older are increasing for both sexes. The increasing hospital admission rate is related to more advanced comorbidities, male sex, and increasing age. These findings have significant implications for neurosurgical resources; they emphasize that health professionals should work proactively with patients, families, and caregivers to clarify goals of care, and they also outline the need for more high-level and, preferably, randomized evidence to support outcomes-based decisions. Additionally, the findings highlight the urgent need for improved population-based measures for prevention in not only this age demographic but in younger ones, and the need for changes in the planning of health service delivery and long-term care.

The suggested chemopreventive association of metformin with prostate cancer in diabetic patients

PURPOSE

Metformin, an insulin sensitizer, is the most common first-line antidiabetic therapy. There is increasing evidence suggesting metformin can prevent the emergence of prostate cancer (CaP). We aimed to analyze the chemopreventive role of metformin, in conjunction with other putative chemopreventive medications (statins, proton-pump-inhibitors, alpha-blockers, 5-alpha-reductase inhibitors, diabetic medications) in a population-based cohort study.

METHODS

Data were incorporated from the Institute for Clinical and Evaluative Sciences to identify all diabetic men aged 66 and above with prior history of a negative prostate biopsy (PB) between 1994 and 2016, who were not on any of the medications prior to study inclusion. Multivariable Cox regression models with time-dependent covariates were used to assess the association of metformin to CaP diagnosis, subsequent PB, and use of androgen deprivation therapy (ADT). All models were adjusted for age, rurality, comorbidity, and year of study inclusion.

RESULTS

Overall, 2,332 diabetic men were included, with a median follow-up time of 9.4 years (interquartile range 5.4-13.4 years). A total of 2,036 patients (87.3%) received metformin. Compared to non-metformin users, metformin use was associated with decreased CaP diagnosis rate (HR 0.69, 95%CI 0.54-0.88, P = 0.003), lower hazard of undergoing an additional PB (HR 0.64, 95%CI 0.44-0.95, P = 0.03), and receiving ADT (HR 0.72, 95%CI 0.54-0.96, P = 0.003).

CONCLUSION

Men receiving metformin were less likely to have suspected or diagnosed CaP, and in those with CaP, the use of ADT was less common. Ongoing prospective randomized studies will determine if these findings correspond to the suggested associations of metformin in the emergence and/or progression of CaP.

Hospital-level Effects Contribute to Variations in Prostate Cancer Quality of Care

A paucity of real-world data exists highlighting whether variations in prostate cancer quality of care occur at a hospital level, independent of differences in case mix. To overcome this knowledge gap, we benchmarked hospital-level quality (n = 1245 hospitals) across a broad multidisciplinary panel of previously reported disease-specific, expert-defined quality indicators (QIs), adjusting for differences in patient case mix by indirect standardization. A composite measure of prostate cancer quality-the prostate cancer quality score (PC-QS)-was derived, and associations between PC-QS and hospital volume, academic status, and location as well as patient all-cause mortality were determined. After adjusting for the case mix, of the total of 1245 hospitals evaluated, 2-37% were identified as those performing significantly below the national average for a given QI. Hospitals with a higher PC-QS displayed larger patient volumes, were more commonly academic affiliated, and had lower overall mortality. Collectively, our data-driven benchmarking analysis reveals that widespread hospital-level variations exist in prostate cancer quality of care after adjusting for differences in case mix, with the PC-QS serving as a novel, validated, quality benchmarking tool. PATIENT SUMMARY: Our statistical benchmarking method shows that the quality of prostate cancer care varies between hospitals, after accounting for differences in patient characteristics. The prostate cancer quality score is a novel, validated, quality benchmarking tool.

Oral Health and Cardiovascular Disease: Mapping Clinical Heterogeneity and Methodological Gaps

BACKGROUND

Numerous studies have examined the associations between poor oral health and the incidence of cardiovascular disease (CVD) over the past 25 y. This long history of research has resulted in a broad and heterogenous epidemiological field whose implications are difficult to understand and whose methodological gaps are hard to track.

OBJECTIVES

This systematic mapping review aims to systematically map clinical heterogeneity and methodological gaps in assessing the relationship between poor oral health and CVD outcomes.

METHODS

Medline, Embase, and Cochrane Library were searched to identify longitudinal studies that examined the relationship between any oral health indicator and CVD outcomes. Each database was searched from its inception date and June 27, 2018. Extracted data assess the clinical heterogeneity (participants' characteristics, exposure and outcome measures, length of follow-up) and methodological gaps (availability of randomized controlled trials, utilization of time-varying exposures, propensity methods, mediation analysis, and competing risks analysis).

RESULTS

Eighty-five studies met the inclusion criteria. Clinical heterogeneity is evident in participants' characteristics (age, clinical status, and occupation) and in the definitions of oral health indicators and CVD outcomes. More important, a significant proportion of studies reported unclear definitions for CVD outcomes. The search strategy did not reveal any randomized controlled trials. Time-varying exposures, propensity methods, mediation analysis, and competing risks analysis are used infrequently in the identified studies.

CONCLUSION

There is a need for a universally accepted conceptual framework on the association between oral health and CVD to derive more consistent definitions for oral health and CVD outcomes that are aligned with the investigated research questions. There is also a need to use emerging research methods to maximize the impact of research in this area.

KNOWLEDGE TRANSFER STATEMENT

Clinical heterogeneity is evident in the definitions of oral health indicators and cardiovascular disease outcomes. Propensity methods, mediation analysis, and competing risks analysis are used infrequently in the identified studies. The identified clinical heterogeneity and methodological gaps interfere with summarizing existing evidence and understanding their practical implications. Advancing the current understanding of the associations between oral health and cardiovascular disease goes hand in hand with minimizing clinical heterogeneity and closing the identified methodological gaps.

DNA methylation profiling to predict recurrence risk in meningioma: development and validation of a nomogram to optimize clinical management

BACKGROUND

Variability in standard-of-care classifications precludes accurate predictions of early tumor recurrence for individual patients with meningioma, limiting the appropriate selection of patients who would benefit from adjuvant radiotherapy to delay recurrence. We aimed to develop an individualized prediction model of early recurrence risk combining clinical and molecular factors in meningioma.

METHODS

DNA methylation profiles of clinically annotated tumor samples across multiple institutions were used to develop a methylome model of 5-year recurrence-free survival (RFS). Subsequently, a 5-year meningioma recurrence score was generated using a nomogram that integrated the methylome model with established prognostic clinical factors. Performance of both models was evaluated and compared with standard-of-care models using multiple independent cohorts.

RESULTS

The methylome-based predictor of 5-year RFS performed favorably compared with a grade-based predictor when tested using the 3 validation cohorts (ΔAUC = 0.10, 95% CI: 0.03-0.018) and was independently associated with RFS after adjusting for histopathologic grade, extent of resection, and burden of copy number alterations (hazard ratio 3.6, 95% CI: 1.8-7.2, P < 0.001). A nomogram combining the methylome predictor with clinical factors demonstrated greater discrimination than a nomogram using clinical factors alone in 2 independent validation cohorts (ΔAUC = 0.25, 95% CI: 0.22-0.27) and resulted in 2 groups with distinct recurrence patterns (hazard ratio 7.7, 95% CI: 5.3-11.1, P < 0.001) with clinical implications.

CONCLUSIONS

The models developed and validated in this study provide important prognostic information not captured by previously established clinical and molecular factors which could be used to individualize decisions regarding postoperative therapeutic interventions, in particular whether to treat patients with adjuvant radiotherapy versus observation alone.

The deleterious association between proton pump inhibitors and prostate cancer-specific mortality - a population-based cohort study

BACKGROUND

Proton pump inhibitors (PPIs) are commonly prescribed medications that have been shown to have contradicting effects on cancer. We aimed to investigate the effect of pantoprazole and other PPIs on prostate cancer (PCa) specific mortality (PCSM), use of androgen deprivation therapy (ADT), and PCa diagnosis using a large Canadian population-based cohort.

METHODS

We identified 21,512 men aged ≥ 66, with a history of a single negative prostate biopsy and no previous use of any of the analyzed medications between 1994 and 2016. Multivariable Cox regression models with time-dependent covariates were used to assess the associations of PPIs with PCa outcomes. All models included other medications with a putative chemopreventative effect on PCa-outcomes, and were adjusted for age, rurality, comorbidity, and study inclusion year.

RESULTS

Over a mean follow-up of 8.06 years (SD 5.44 years), 10,999 patients (51.1%) used a PPI, 5187 patients (24.1%) had PCa, 2043 patients (9.5%) were treated with ADT, and 805 patients (3.7%) died from PCa. For every 6 months of cumulative use, pantoprazole was associated with a 3.0% (95% CI 0.3-6.0%) increased rate of ADT use, while any use of other PPIs was associated with a 39.0% (95% CI 18.0-64.0%) increased risk of PCSM. No association was found with PCa diagnosis.

CONCLUSIONS

Upon validation of the potentially negative association of PPIs with PCa, PPI use may need to be reassessed in PCa patients.

The Suggested Unique Association Between the Various Statin Subgroups and Prostate Cancer

BACKGROUND

The chemopreventive effect of various medications in prostate cancer (PCa) has gained interest. Specifically, the potential impact of statins on PCa incidence has been studied, but solely as a "drug family" overlooking the distinctive pharmacological properties of its two main subgroups: hydrophilic and hydrophobic statins.

OBJECTIVE

To assess the impact of statin subgroups on PCa-specific mortality (PCSM), PCa diagnosis, and undergoing another prostate biopsy.

DESIGN, SETTING, AND PARTICIPANTS

This is a population-based cohort study in Ontario identifying all men aged ≥66 yr with a history of a single negative prostate biopsy (representing healthy men at risk for PCa) between 1994 and 2016, who were not on any of the analyzed medications prior to the study, with a median follow-up of 9.42 yr (interquartile range 8.03 yr).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Using multivariable cause-specific hazard models with time-dependent covariates, the association of hydrophobic and hydrophilic statins with all study outcomes was analyzed. Other putative chemopreventive medications (including alpha-blockers, 5-alpha-reductase inhibitors, and proton-pump inhibitors), age, rurality, comorbidities, and study inclusion year were included in the models.

RESULTS AND LIMITATIONS

Overall, 21 512 men were identified. Statins were taken by 11 401 patients (50.3%), 5184 men (24.1%) were diagnosed with PCa, and 805 (3.7%) died from it. Overall, 7556 patients (35.1%) underwent another biopsy. Any use of hydrophilic statins was associated with a 32.4% (95% confidence interval [CI] 12.9-47.5%), a 20% (95% CI 10-28%), and an 18% (95% CI 6.1-27.3%) decreased risk of PCSM, undergoing another prostate biopsy, and being diagnosed with PCa, respectively. Hydrophobic statins were associated with 17% (95% CI 2-31%) decreased PCSM. The study is limited by its retrospective nature, selection bias, and accompanying health-administrative database inaccuracies.

CONCLUSIONS

Use of any statin may be associated with a lower hazard of PCSM, with hydrophilic statins showing a greater association with decreased PCa diagnosis rates. Preferentially prescribing one statin subgroup over another in men needs further exploration.

PATIENT SUMMARY

Use of any statin may be associated with a lower probability of dying from prostate cancer. Hydrophilic statins (rosuvastatin and pravastatin) may also be more positively associated with a lower risk of undergoing an additional prostate biopsy and being diagnosed with prostate cancer in men aged ≥66 yr.

Long-term outcomes after radical or partial nephrectomy for T1a renal cell carcinoma: A population-based study

INTRODUCTION

The benefit of partial nephrectomy (PN) compared to radical nephrectomy (RN) for T1a renal cell carcinoma (RCC) remains uncertain, with observational studies conflicting with level 1 evidence. Therefore, the purpose of this population-based study was to compare long-term outcomes in patients undergoing PN or RN for T1a RCC.

METHODS

We studied 5670 patients in Ontario, Canada undergoing PN or RN for T1a RCC. The primary outcome was overall survival (OS). Secondary outcomes were cancer-specific survival (CSS), chronic kidney disease (CKD), renal replacement therapy, and myocardial infarction (MI). We used multivariable Cox proportional hazard models to evaluate the association between PN or RN and these outcomes. A sensitivity analysis was performed in patients with a preoperative serum creatinine available.

RESULTS

Median followup was 77 months. Compared to RN, PN was associated with significantly improved OS (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.63-0.84), reduced risk of CKD (HR 0.18, 95% CI 0.12-0.27), and improved CSS (HR 0.45, 95% CI 0.30-0.65). The risk of MI was not significantly different between groups (HR 0.91, 95% CI 0.62-1.34). Few patients (n=15) required renal replacement therapy. In the sensitivity analysis, the association between type of surgery and OS and CKD persisted, while the association with CSS did not.

CONCLUSIONS

Our study found that in patients undergoing surgery for T1a RCC, PN was associated with improved OS and reduced risk of CKD compared to RN. However, few patients in either group required renal replacement therapy.

Gastrectomy case volume and textbook outcome: an analysis of the Population Registry of Esophageal and Stomach Tumours of Ontario (PRESTO)

OBJECTIVE

To determine the association between gastric cancer surgery case-volume and Textbook Outcome, a new composite quality measurement.

BACKGROUND

Textbook Outcome included (a) negative resection margin, (b) greater than 15 lymph nodes sampled, (c) no severe complication, (d) no re-intervention, (e) no unplanned ICU admission, (f) length of stay of 21 days or less, (g) no 30-day readmission and (h) no 30-day mortality following surgery.

METHODS

All patients undergoing gastrectomy for non-metastatic gastric adenocarcinoma registered in the Population Registry of Esophageal and Stomach Tumours of Ontario between 2004 and 2015 were included. We used multivariable generalized estimating equation (GEE) logistic regression modelling to estimate the association between gastrectomy volume (surgeon and hospital annual volumes) and Textbook Outcome. Volumes were considered as continuous variables and quintiles.

RESULTS

Textbook Outcome was achieved in 378 of 1660 patients (22.8%). The quality metrics least often achieved were inadequate lymph node sampling and presence of severe complications, which occurred in 46.1% and 31.7% of patients, respectively. Accounting for covariates and clustering, neither surgeon volume nor hospital volume were significantly associated with Textbook Outcome. However, hospital volume was associated with adequate lymphadenectomy and fewer unplanned ICU admissions.

CONCLUSIONS

Higher case volume can impact certain measures of quality of care but may not address all care structures necessary for ideal Textbook recovery. Future quality improvement strategies should consider using case-mix adjusted Textbook Outcome rates as a surgical quality metric.

Pilot Study of the Juvenile Dermatomyositis Consensus Treatment Plans: A CARRA Registry Study

OBJECTIVES

To determine the feasibility of comparing the Childhood Arthritis and Rheumatology ResearchAlliance (CARRA) consensus treatment plans (CTP) in treating moderate new-onset juvenile dermatomyositis (JDM) using the CARRA registry, and to establish appropriate analytic methods to control for confounding by indication and missing data.

METHODS

A pilot cohort of 39 patients with JDM from the CARRA registry was studied. Patients were assigned by the treating physician, considering patient/family preferences, to 1 of 3 CTP: methotrexate (MTX) and prednisone (MP); intravenous (IV) methylprednisolone, MTX, and prednisone (MMP); or IV methylprednisolone, MTX, prednisone, and IV immunoglobulin (MMPI). The primary outcome was the proportion of patients achieving moderate improvement at 6 months under each CTP. Statistical methods including multiple imputation and inverse probability of treatment weighting were used to handle missing data and confounding by indication.

RESULTS

Patients received MP (n = 13), MMP (n = 18) and MMPI (n = 8). Patients in all CTP had significant improvement in disease activity. Of the 36 patients who remained in our pilot study at 6 months, 16 (44%) of them successfully achieved moderate improvement at 6 months (6/13, 46% for MP; 7/15, 47% for MMP; 3/8, 38% for MMPI). After correcting for confounding, there were no statistically significant pairwise differences between the CTP (P = 0.328-0.88).

CONCLUSION

We gained valuable experience and insight from our pilot study that can be used to guide the design and analysis of comparative effectiveness studies using the CARRA registry CTP approach. Our analytical methods can be adopted for future comparative effectiveness studies and applied to other rare disease observational studies.

The deleterious association between proton pump inhibitors and prostate cancer specific death

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Background: Proton pump inhibitors (PPIs) are a commonly prescribed class of medications. Although in-vitro and in-vivo data have shown PPIs to have anti-tumor effects, more recent studies suggest an increased cancer risk in several solid organs. Pantoprazole, a commonly prescribed PPI, has been shown to harbor a protective effect in human prostate cancer (PCa) cells. We aimed to investigate the effect of pantoprazole and other PPIs on PCa-specific death and additional PCa outcomes. Methods: In this retrospective, population-based cohort study, data were incorporated from the Institute for Clinical and Evaluative Sciences to identify all men aged 66 and above with a history of a single negative prostate biopsy between 1994 and 2016. We used multivariable Cox regression models with time-dependent covariates, to assess the effect of PPIs on PCa diagnosis, androgen deprivation therapy (ADT) use, and PCa-specific death. All models included other medications with a putative effect on PCa. All models were adjusted for age, rurality, comorbidity, and year of patient study inclusion. Results: Overall, 21,512 men were included, with a mean follow-up time of 8.06 years (SD 5.44 years). A total of 10,999 patients (51.1%) used a PPI. A total of 5,187 patients (24.1%) were diagnosed with PCa, 2,043 patients (9.5%) were treated with ADT, and 805 patients (3.7%) died from PCa. Pantoprazole was associated with a 3.0% (95% CI 0.3%-6,0%) increased rate of being treated with ADT for every six months of cumulative use, while any use of all other PPIs was associated with a 39.0% (95% CI 18.0%-64.0%) increased PCa-specific mortality. No significant association was found with PCa diagnosis. Conclusions: Upon validation of the potentially negative association of PPIs with PCa outcomes, the expansive use of PPIs may need to be reassessed, especially in PCa patients.

Hospital-level quality indicators for kidney cancer surgery: A Veteran’s Affairs national health system validation of concept

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Background: Validation and implementation of quality indicators (QIs) for oncological surgical care is imperative in national health care systems. However, QIs must be adjusted for significant case-mix variations among hospitals and to capture disparate patient outcomes. Here, we explore and validate a compound quality score (CQS) as a metric for hospital-level quality of care in kidney cancer patients. Methods: Kidney cancer patients (n = 8233) treated at the VA (2005-2015) were identified. Two previously described and validated process QIs were explored: the proportion of patients with a) T1a tumors undergoing partial nephrectomy; and b) T1-T2 tumors undergoing minimally invasive radical nephrectomy. Demographics, comorbidity, tumor characteristics and treatment year were used for case-mix adjustment using indirect standardization / multivariable regression models. The predicted vs observed ratio of cases was calculated to generate each QI score. CQS represents the sum of both QIs scores. Ninety-six hospitals were benchmarked by CQS and patient-level outcomes were regressed on CQS levels to assess for length of stay (LOS), 30 days complications/readmission, 90 days overall mortality and total cost of surgical admission. Results: CQS identified 25, 33 and 38 hospitals with higher, lower and average performance, respectively. Total CQS score was independently associated with LOS [β = -0.04, p< 0.01, predicted LOS 0.84 days shorter for CQS = 2 vs. CQS = -2], 30 days surgical complications [OR = 0.88, p < 0.01] or 30 days medical complications [OR = 0.93, p < 0.01] and total cost of surgical admission [β = -0.014, p< 0.01, predicted 12% lower cost for CQS = 2 vs. CQS = -2]. No association was found between CQS and 30 day readmissions or 90 days mortality (all p>0.05), although low event rates were observed (8.9% and 1.7%, respectively). Conclusions : Variability in quality of surgical care at a hospital-level can be captured with the CQS among kidney cancer patients. CQS is associated with length of stay, post-operative complications and total cost of surgical admission. Quality indicators should be used to identify, audit and implement quality improvement strategies across health systems.

Estimation of causal effects with repeatedly measured outcomes in a Bayesian framework

Constructing causal inference methods to handle longitudinal data in observational studies is of high interest. In an observational setting, treatment assignment at each clinical visit follows a decision strategy where the treating clinician selects treatment based on current and past clinical measurements as well as treatment histories. These time-dependent structures, coupled with inherent correlations between and within each visit, add on to the data complexity. Despite recent interest in Bayesian causal methods, only a limited literature has explored approaches to handle longitudinal data and no method handles repeatedly measured outcomes. In this paper, we extended two Bayesian approaches: Bayesian estimation of marginal structural models and two-stage Bayesian propensity score analysis to handle a repeatedly measured outcome. Our proposed methods permit causal estimation of treatment effects at each visit. Time-dependent inverse probability of treatment weights are obtained from the Markov chain Monte Carlo samples of the posterior treatment assignment model for each follow-up visit. We use a simulation study to validate and compare the proposed methods and illustrate our approaches through a study of intravenous immunoglobulin therapy in treating newly diagnosed juvenile dermatomyositis.

Medical Assessment of Head Collision Events in Elite Women's and Men's Soccer

This study uses data from the 2019 Fédération Internationale de Football Association Women’s World Cup to determine the incidence rate and subsequent medical assessment of head collision events.

Causal variance decompositions for institutional comparisons in healthcare

There is increasing interest in comparing institutions delivering healthcare in terms of disease-specific quality indicators (QIs) that capture processes or outcomes showing variations in the care provided. Such comparisons can be framed in terms of causal models, where adjusting for patient case-mix is analogous to controlling for confounding, and exposure is being treated in a given hospital, for instance. Our goal here is to help identify good QIs rather than comparing hospitals in terms of an already chosen QI, and so we focus on the presence and magnitude of overall variation in care between the hospitals rather than the pairwise differences between any two hospitals. We consider how the observed variation in care received at patient level can be decomposed into that causally explained by the hospital performance adjusting for the case-mix, the case-mix itself, and residual variation. For this purpose, we derive a three-way variance decomposition, with particular attention to its causal interpretation in terms of potential outcome variables. We propose model-based estimators for the decomposition, accommodating different link functions and either fixed or random effect models. We evaluate their performance in a simulation study and demonstrate their use in a real data application.

Outcomes and prognosticators of stage 4 renal cell carcinoma with pathological T4 primary lesion using a large, Canadian, multi-institutional database

INTRODUCTION

The primary objective of this study was to evaluate outcomes and prognosticators in patients who underwent radical nephrectomy (RN) or cytoreductive nephrectomy (CN), depending on the clinical stage of disease preoperatively, with a pathological T4 (pT4) renal cell carcinoma (RCC) outcome. There is little data on the outcome of this specific subset of patients.

METHODS

From 2009-2016, we identified patients in the Canadian Kidney Cancer information system (CKCis) who underwent RN or CN and were found to have pT4 RCC. Clinical, operative, and pathological variables were analyzed with univariable and multivariable Cox proportional hazard models to identify factors associated with overall survival (OS). Survival curves were created using Kaplan-Meier methods and compared using the log-rank test.

RESULTS

A total of 82 patients were included in the study cohort. Median patient age was 62 years (interquartile range [IQR] 55, 70). Fifty (61%) patients had clear-cell histology and 14 (17%) had sarcomatoid characteristics. Median followup was 12 months (IQR 3, 24). At last followup, eight (10%) patients are alive with no evidence of disease, 27 (33%) are alive with disease, four (5%) were lost to followup, 36 (44%) died of disease, and seven (8%) died of other causes. Tumor histological subtype (clear-cell vs. non-clear-cell) (p=0.0032), larger tumor size (cm) (p=0.012), and Fuhrman grade (G4 vs. G2-G3) (p=0.045) were significantly associated with mortality in a multivariable Cox regression model.

CONCLUSIONS

For patients with pT4 RCC after RN or CN, survival is poor. Sarcomatoid features, non-clear-cell histology, and presence of systemic symptoms were associated with worse OS.

Causal Mediation Analysis for Standardized Mortality Ratios

Indirectly standardized mortality ratios (SMR) are often used to compare patient outcomes between health care providers as indicators of quality of care. Observed differences in the outcomes raise the question of whether these could be causally attributable to earlier processes or outcomes in the pathway of care that the patients received. Such pathways can be naturally addressed in a causal mediation analysis framework. Adopting causal mediation models allows the total provider effect on outcome to be decomposed into direct and indirect (mediated) effects. This in turn enables quantification of the improvement in patient outcomes due to a hypothetical intervention on the mediator. We formulate the effect decomposition for the indirectly standardized SMR when comparing to a health care system-wide average performance, propose novel model-based and semiparametric estimators for the decomposition, study the properties of these through simulations, and demonstrate their use through application to Ontario kidney cancer data.

Mendelian Randomization and mediation analysis of leukocyte telomere length and risk of lung and head and neck cancers

BACKGROUND

Evidence from observational studies of telomere length (TL) has been conflicting regarding its direction of association with cancer risk. We investigated the causal relevance of TL for lung and head and neck cancers using Mendelian Randomization (MR) and mediation analyses.

METHODS

We developed a novel genetic instrument for TL in chromosome 5p15.33, using variants identified through deep-sequencing, that were genotyped in 2051 cancer-free subjects. Next, we conducted an MR analysis of lung (16 396 cases, 13 013 controls) and head and neck cancer (4415 cases, 5013 controls) using eight genetic instruments for TL. Lastly, the 5p15.33 instrument and distinct 5p15.33 lung cancer risk loci were evaluated using two-sample mediation analysis, to quantify their direct and indirect, telomere-mediated, effects.

RESULTS

The multi-allelic 5p15.33 instrument explained 1.49-2.00% of TL variation in our data (p = 2.6 × 10-9). The MR analysis estimated that a 1000 base-pair increase in TL increases risk of lung cancer [odds ratio (OR) = 1.41, 95% confidence interval (CI): 1.20-1.65] and lung adenocarcinoma (OR = 1.92, 95% CI: 1.51-2.22), but not squamous lung carcinoma (OR = 1.04, 95% CI: 0.83-1.29) or head and neck cancers (OR = 0.90, 95% CI: 0.70-1.05). Mediation analysis of the 5p15.33 instrument indicated an absence of direct effects on lung cancer risk (OR = 1.00, 95% CI: 0.95-1.04). Analysis of distinct 5p15.33 susceptibility variants estimated that TL mediates up to 40% of the observed associations with lung cancer risk.

CONCLUSIONS

Our findings support a causal role for long telomeres in lung cancer aetiology, particularly for adenocarcinoma, and demonstrate that telomere maintenance partially mediates the lung cancer susceptibility conferred by 5p15.33 loci.

Estimating Case-Fatality Reduction from Randomized Screening Trials

In randomized cancer screening trials where asymptomatic individuals are assigned to undergo a regimen of screening examinations or standard care, the primary objective typically is to estimate the effect of screening assignment on cancer-specific mortality by carrying out an ’intention-to-screen’ analysis. However, most of the participants in the trial will be cancer-free; only those developing a genuine cancer that is screening-detectable can potentially benefit from screening induced early treatments. Here we consider measuring the effect of early treatments in this partially latent subpopulation in terms of reduction in case fatality. To formalize the estimands and identifying assumptions in a causal modeling framework, we first define two measures, namely proportional and absolute case-fatality reduction, using potential outcomes notation. We re-derive an earlier proposed estimator for the former, and propose a new estimator for the latter motivated by the instrumental variable approach. The methods are illustrated using data from the US National Lung Screening Trial, with specific attention to estimation in the presence of censoring and competing risks.