Using Propensity Scores for Causal Inference: Pitfalls and Tips

Early outcomes of robotic versus video-thoracoscopic anatomical segmentectomy: a propensity score-matched real-world study

OBJECTIVES

Minimally invasive anatomic segmentectomy for the resection of pulmonary nodules has significantly increased in the last few years. Nevertheless, there is limited evidence on the safety and feasibility of robotic segmentectomy compared to video-assisted thoracic surgery. This study aimed to compare the real-world early outcomes of robotic and video-thoracoscopic surgery in anatomic segmentectomy.

METHODS

Single-centre cohort study including all consecutive patients undergoing segmentectomy by either robotic or video-thoracoscopic from June 2018 to November 2023. Propensity score case matching analysis generated 2 matched groups undergoing robotic or video-thoracoscopic segmentectomy. Short-term outcomes were analysed and compared between groups.

RESULTS

204 patients (75 robotic and 129 video-thoracoscopic patients) were included. After matching, 146 patients (73 cases in each group) were compared. One 30-day death was observed in the robotic group (P = 1). Two conversions to thoracotomy occurred in the robotic, and none in the video-thoracoscopic group (P = 0.5). Surgical time was longer in the robotic group (P = 0.091). There were no significant differences between robotic and video-thoracoscopic groups in postoperative complications (13.7% vs 15.1%, P = 1), cardiopulmonary complications (6.8% vs 6.8%, P = 1), major complications (4.1% vs 4.1%, P = 1), prolonged air leak (4.1% vs 5.5%, P = 1), arrhythmia (1.4% vs 0%, P = 1) and reoperation (2.7% vs 2.7%, P = 1). Median length of stay was 3 days (interquartile range 2-3 days) in the robotic group vs 3 days (interquartile range 2.5-4 days) in the video-thoracoscopic group (P = 0.212).

CONCLUSIONS

Robotic segmentectomy is a safe and feasible alternative to video-thoracoscopy, as no significant differences in early postoperative outcomes were found between the 2 techniques.

Role of Doulas in Improving Maternal Health and Health Equity Among Medicaid Enrollees, 2014‒2023

Objectives. To assess the relationship between doula utilization and health outcomes of females enrolled in Medicaid-affiliated plans in the United States. Methods. In this retrospective, observational cohort study, we used Medicaid claims data from a national health insurer to compare health outcomes between females who used and who did not use a doula (2014-2023). We conducted propensity score matching using a 1:1 case‒control match, without replacement, and fit logistic regressions to analyze the relative risks for maternal health outcomes. Results. The study population included 722 matched pairs with and without a doula. Results indicate females with doulas had a 47% lower risk of cesarean delivery and a 29% lower risk of preterm birth, and were 46% more likely to attend a postpartum checkup (all differences P < .05). Conclusions. Doula care is associated with improved health outcomes among Medicaid enrollees. Public Health Implications. Doulas have garnered increasing interest from policymakers as a strategy to address increasing trends in maternal morbidity and persistent health disparities. This study provides evidence from Medicaid enrollees across the United States that doula care can improve maternal health. (Am J Public Health. 2024;114(11):1275-1285. https://doi.org/10.2105/AJPH.2024.307805).

Prognostic impact of postoperative management by an intensive care unit intensivist after colonic perforation

PURPOSE

Postoperative management for colonic perforation is an important prognostic factor, but whether intensivists perform postoperative management varies between institutions.

METHODS

We investigated 291 patients with colonic perforation between 2018 and 2022. Patients were divided into those managed by an intensivists (ICU group; n = 40) and those not managed by an intensivists (non-ICU group; n = 251). We examined how management by intensivists affected prognosis using inverse probability weighting, and clarified which patients should consult an intensivists.

RESULTS

The ICU group showed a significantly higher shock index (1.15 vs. 0.75, p < 0.01), higher APACHE II score (16.0 vs. 10.0, p < 0.001), and more severe comorbidities (Charlson Comorbidity Index 5.0 vs. 1.0, p < 0.001) and general peritonitis (85% vs. 38%, p < 0.001). Adjusted risk differences were - 24% (-34% to -13%) for 6-month mortality rate. Six-month mortality was improved by ICU intensivist management in patients with general peritonitis (risk difference - 22.8; 95% confidence interval - 34 to -11); APACHE II score ≥20 (-0.79; -1.06 to -0.52); lactate ≥1.6 (-0.38; -0.57 to -0.29); shock index ≥1.0 (-40.01; -54.87 to -25.16); and catecholamine index ≥10 (-41.16; -58.13 to -24.19).

CONCLUSIONS

Intensivists were involved in treating patients in poor general condition, but prognosis was extremely good. Appropriate case consultation with intensivists is important.

Anti-IL-4R versus anti-IL-5/5R after anti-IL-5/5R failure in asthma: An emulated target trial

BACKGROUND

Switching biologics is now common practice in severe eosinophilic asthma. After insufficient response to anti-IL-5 or 5 receptor (anti-IL-5/5R), the optimal switch between an anti-IL-4R mAb (interclass) or another anti-IL-5/5R drug (intraclass) remains unknown.

OBJECTIVE

We sought to compare the effectiveness of these 2 strategies in asthma control in patients with severe eosinophilic asthma and insufficient response to an anti-IL-5/5R mAb.

METHODS

We emulated a target randomized trial using observational data from the Recherche sur les AsthMes SEvèreS (RAMSES) cohort. Eligible patients were switched to an anti-IL-4R mAb or another anti-IL-5/5R drug after insufficient response to an anti-IL-5/5R mAb. The primary outcome was the change in Asthma Control Test score at 6 months.

RESULTS

Among the 2046 patients in the cohort, 151 were included in the study: 103 switched to an anti-IL-4R mAb and 48 to another anti-IL-5/5R. At 6 months, the difference in Asthma Control Test score improvement was not statistically significant (mean difference groups, 0.82 [-0.47 to 2.10], P = .213). The interclass group exhibited greater cumulative reduction in oral corticosteroid dose (Pinter-intra, -1.05 g [-1.76 to -0.34], P = .041). The interclass group had a better effect, although not significantly, on reducing exacerbations (Δinter-intra, -0.37 [-0.77 to 0.02], P = .124) and increasing lung function (FEV1) (126.8 mL [-12.7 to 266.4], P = .124).

CONCLUSIONS

After anti-IL-5/5R mAb insufficient response, switching to dupilumab demonstrated similar improvement in Asthma Control Test scores compared with intraclass switching. However, it appeared more effective in reducing oral corticosteroid use. Larger studies are warranted to confirm these results.

The Impact of Gardening on Dietary Inflammation: Mixed-Effect Models and Propensity Score Analyses

Introduction

Gardening has been found to increase vegetable intake and reduce BMI; this suggests that it may improve diets by lowering inflammatory content. The goal of this study goal was to evaluate the effect of gardening on Dietary Inflammatory Index scores.

Methods

Longitudinal data were collected annually between 2015 and 2018 from adults in low-income, urban neighborhoods of Cleveland and Columbus, Ohio. The authors measured the association between gardening and Dietary Inflammatory Index in the full data set using multivariable mixed-effect models with a random intercept for participant (Model 1; n=409). To further explore potential causation, the author used propensity score analyses in a subset of the data by building a 1-to-1 matched model (Model 2; n=339).

Results

Of 409 adults, 30.3% were gardeners with Dietary Inflammatory Index scores ranging from -6.228 to +6.225. Participating in gardening was associated with lower Dietary Inflammatory Index scores in the mixed-effects model (-0.45; 95% CI= -0.85, -0.04; Model 1) and the 1-to-1 matched model (-0.77; 95% CI= -1.40, -0.14; Model 2).

Conclusions

The analyses indicate that gardeners had lower Dietary Inflammatory Index scores than nongardeners, implying lower diet-driven inflammation. These findings highlight the potential for a causal relationship between gardening and Dietary Inflammatory Index, which should be confirmed in future studies. If this relationship is validated, strategies to increase gardening may be worth testing as primary prevention tools for diet-driven chronic disease.

Prevalence of right-to-left shunt in stroke patients with cancer

BACKGROUND AND OBJECTIVES

Cancer is associated with an increased risk of acute ischemic stroke (AIS) and venous thromboembolism. The role of a cardiac right-to-left shunt (RLS) as a surrogate parameter for paradoxical embolism in cancer-related strokes is uncertain. We sought to investigate the relationship between the presence of an RLS and cancer in AIS patients.

METHODS

We included consecutive AIS patients hospitalized at our tertiary stroke center between January 2015 and December 2020 with available RLS status as detected on transesophageal echocardiography (TEE). Active cancers were retrospectively identified and the association with RLS was assessed with multivariable logistic regression and inverse probability of treatment weighting to minimize the ascertainment bias of having a TEE obtained.

RESULTS

Of the 2236 AIS patients included, 103 (4.6%) had active cancer, of whom 24 (23%) were diagnosed with RLS. An RLS was present in 774 out of the 2133 AIS patients without active cancer (36%). After adjustment and weighting, the absence of RLS was associated with active cancer (adjusted odds ratio (aOR) 2.29; 95% confidence interval (CI), 1.14-4.58). When analysis was restricted to patients younger than 60 years of age or those with a high-risk RLS (Risk of Paradoxical Embolism Score ⩾ 6), there was no association between RLS and cancer (aOR, 3.07; 95% CI, 0.79-11.88 and aOR, 0.56; 95% CI, 0.10-3.10, respectively).

CONCLUSION

RLS was diagnosed less frequently in AIS patients with cancer than in cancer-free patients, suggesting that arterial sources may play a larger role in cancer-related strokes than paradoxical venous embolization. Future studies are needed to validate these findings and evaluate potential therapeutic implications, such as the general indication, or lack thereof, for patent foramen ovale (PFO) closure in this patient population.

Real-world evidence of sotrovimab effectiveness for preventing severe outcomes in patients with COVID-19: A quality improvement propensity-matched retrospective cohort study of a pan-provincial program in Alberta, Canada

OBJECTIVES

Post-marketing surveillance of sotrovimab's effect during implementation in the Canadian population is limited.

METHODS

The study used a propensity score-matched retrospective cohort design. Follow-up began between the periods of December 15, 2021 and April 30 2022. The study assessed any severe outcome defined as all-cause hospital admission or mortality within 30 days of a confirmed COVID-19-positive test. Covariate-adjusted odds ratios between sotrovimab treatment and the severe outcome was conducted using logistic regression.

RESULTS

There were 22,289 individuals meeting the treatment criteria for sotrovimab. There were 1603 treated and 6299 untreated individuals included in the analysis. The outcome occurrence in the study was 5.49% (treated) and 4.21% (untreated), with a median time from diagnosis to treatment of 1.00 days (interquartile range 2.00 days). In the propensity-matched cohort, sotrovimab was not associated with lower odds of a severe outcome (odds ratio 1.20, 95% confidence interval 0.91-1.58), adjusting for confounding variables.

CONCLUSIONS

After adjusting for confounding variables, sotrovimab treatment was not associated with lower odds of a severe outcome within 30-days of COVID-19-positive date.

The impact of statin use on sepsis mortality

BACKGROUND

Statins exert pleiotropic anti-inflammatory and antioxidant effects in addition to their cholesterol-lowering properties. This study aimed to investigate whether statin use is associated with improved outcomes of sepsis.

METHODS

Data from sepsis patients were extracted from the Medical Information Mart for Intensive Care IV database. Patients with a history of receiving prescriptions for statins (i.e. atorvastatin, lovastatin, pitavastatin, pravastatin, rosuvastatin, or simvastatin) were matched with non-users using propensity-score matching, to balance confounding factors between the groups. Mendelian Randomization (MR) analyses were performed using information from the UK Biobank dataset to explore the potential causal link between low-density lipoprotein cholesterol (LDL-C) levels and LDL-C lowering effects via genetically inhibiting β‑hydroxy β-methylglutaryl-coenzyme A reductase and the susceptibility to sepsis, and the sepsis-related 28-day mortality.

MAIN RESULTS

90-day mortality rate was lower among the 10,323 statin users when compared to matched non-users [hazard ratio (HR): 0.612, 95 % CI: 0.571 to 0.655]. In-hospital mortality was also lower for statin users compared to non-users (11.3% vs. 17.8 %, p < 0.0001, HR: 0.590, 95 % CI: 0.548 to 0.634). Statin use was associated with better outcome in all investigated subpopulations apart from patients with severe liver disease. MR analyses further pointed toward pleiotropic effects beyond lipid-lowering effects of statins on sepsis-related outcomes.

CONCLUSIONS

Statin use is associated with improved outcomes following sepsis-related ICU admission, most likely from its pleiotropic properties, characterized by lower 90-day and in-hospital mortality among statin users.

Proton pump inhibitors are not associated with fundic gland polyps - a systematic review that takes into consideration all known confounders

Sporadic fundic gland polyps (FGPs) progress, albeit rarely, to dysplasia and cancer. Two meta-analyses, including 8 and 11 studies, concluded that proton pump inhibitors (PPIs) were associated with FGPs. Intervention is considered unnecessary when FGPs have a background of PPIs use. Both meta-analyses, however, disregarded known confounders: age, sex, endoscopy indications, study design (prospective or retrospective), duration of PPI use, and H. pylori infection. Confounders are known to invalidate meta-analyses. We followed PRIXMA guidelines and searched the literature for studies on FGPs in PPI-users and PPI-nonusers. In the 22 studies searched, we compared FGPs in PPI-users (n = 6534) and PPI-nonusers (n = 41 115). Heterogeneity was significant (Cochran Q = 277.8, P < 0.0001; I2 = 92.8%), annulling meta-analysis performed by blanket tallying. To offset the above confounders, we matched PPI-users and PPI-nonusers by (a) age and sex (n = 4300 and 29 307, respectively) and (b) their propensity scores derived from the confounders (n = 2950 and 4729, respectively). After both matching, FGPs were not significantly different between PPI-users and PPI-nonusers [odds ratio (OR) = 1.1, P = 0.3078; OR = 0.9, P = 0.3258, respectively]. Furthermore, FGP frequency did not correlate with increasing duration of PPI use (Pearson and Spearman correlation coefficients = 0.1162, 0.0386, P < 0.6064, 0.8646, respectively); it was not significantly different between any of the duration periods of observation, namely, <10, 10-20, 20-40, >40 months, nor was it significantly different between PPI-users and PPI-nonusers within each duration period (P > 0.05). We conclude that PPIs are not associated with FGPs, implying that a background history of PPI use is not a justification for nonintervention in the management of FGPs.

No evidence of difference in mortality with amoxicillin versus co-amoxiclav for hospital treatment of community-acquired pneumonia

OBJECTIVES

Current guidelines recommend broad-spectrum antibiotics for high-severity community-acquired pneumonia (CAP), potentially contributing to antimicrobial resistance (AMR). We aim to compare outcomes in CAP patients treated with amoxicillin (narrow-spectrum) versus co-amoxiclav (broad-spectrum), to understand if narrow-spectrum antibiotics could be used more widely.

METHODS

We analysed electronic health records from adults (≥16 y) admitted to hospital with a primary diagnosis of pneumonia between 01-January-2016 and 30-September-2023 in Oxfordshire, United Kingdom. Patients receiving baseline ([-12 h,+24 h] from admission) amoxicillin or co-amoxiclav were included. The association between 30-day all-cause mortality and baseline antibiotic was examined using propensity score (PS) matching and inverse probability treatment weighting (IPTW) to address confounding by baseline characteristics and disease severity. Subgroup analyses by disease severity and sensitivity analyses with missing covariates imputed were also conducted.

RESULTS

Among 16,072 admissions with a primary diagnosis of pneumonia, 9685 received either baseline amoxicillin or co-amoxiclav. There was no evidence of a difference in 30-day mortality between patients receiving initial co-amoxiclav vs. amoxicillin (PS matching: marginal odds ratio 0.97 [0.76-1.27], p = 0.61; IPTW: 1.02 [0.78-1.33], p = 0.87). Results remained similar across stratified analyses of mild, moderate, and severe pneumonia. Results were also similar with missing data imputed. There was also no evidence of an association between 30-day mortality and use of additional macrolides or additional doxycycline.

CONCLUSIONS

There was no evidence of co-amoxiclav being advantageous over amoxicillin for treatment of CAP in 30-day mortality at a population-level, regardless of disease severity. Wider use of narrow-spectrum empirical treatment of moderate/severe CAP should be considered to curb potential for AMR.

Regional trends in diagnosis of advanced lung cancer in Michigan over 33 years

Background

Lung cancer is the most common cancer killer worldwide. Nearly 80 percent of lung cancers are diagnosed at advanced stages. Lack of access to medical care and undwerutilized lung cancer screening are key reasons for advanced diagnoses. We sought to understand the regional differences in presentation of lung cancer across Michigan. Utilizing a comprehensive cancer registry over 33 years, our goal was to examine associations between sociodemographic patient factors and diagnoses at advanced stages.

Methods

The Michigan Cancer Registry was queried from 1985 to 2018 to include all new diagnoses of non-small cell lung cancer (NSCLC) using International Classification of Diseases for Oncology (ICD-O) version 3 codes. NSCLC was categorized as early, regional and distant disease. Advanced disease was considered to be any disease that was regional or distant. NSCLC rates were calculated and mapped at the zip code level using the 2010 population as the denominator and spatial empirical Bayes methodology. Regional hospital service areas were constructed using travel time to treatment from the patient's zip code centroid. Logistic regression models were estimated to investigate the significance of rural vs. urban and travel time on level of disease at presentation. Kaplan-Meier and multivariate survival analysis was performed to evaluate the association between distance from the nearest medical center and length of survival controlling for known risk factors for lung cancer.

Results

From 1985 to 2018, there were 141,977 patients in Michigan diagnosed with NSCLC. In 1985, men were 2.2 times more likely than women to be diagnosed but by 2018 women and men developed disease at equal rates. Mean age was 67.8 years. Among all patients with known stage of disease, 72.5% of patients were diagnosed with advanced disease. Regional and distant NSCLC rates were both higher in the northern parts of the state. Longer drive times in rural regions also significantly increased the likelihood of advanced NSCLC diagnoses, in particular regional lung cancer. Patients with longer drive times also experienced overall worse survival after controlling for other factors.

Conclusions

Regional disparities exist in Michigan for diagnoses of NSCLC at advanced stages. Factors such as lack of screening in urban regions and distances to treating institutions in rural areas likely contribute to the increased likelihood of advanced NSCLC. Future interventions should target the specific needs of residents to detect disease at earlier stages and improve overall outcomes.

Association between allostatic load and accelerated white matter brain aging: findings from the UK Biobank

White matter (WM) brain age, a neuroimaging-derived biomarker indicating WM microstructural changes, helps predict dementia and neurodegenerative disorder risks. The cumulative effect of chronic stress on WM brain aging remains unknown. In this study, we assessed cumulative stress using a multi-system composite allostatic load (AL) index based on inflammatory, anthropometric, respiratory, lipidemia, and glucose metabolism measures, and investigated its association with WM brain age gap (BAG), computed from diffusion tensor imaging data using a machine learning model, among 22 951 European ancestries aged 40 to 69 (51.40% women) from UK Biobank. Linear regression, Mendelian randomization, along with inverse probability weighting and doubly robust methods, were used to evaluate the impact of AL on WM BAG adjusting for age, sex, socioeconomic, and lifestyle behaviors. We found increasing one AL score unit significantly increased WM BAG by 0.29 years in association analysis and by 0.33 years in Mendelian analysis. The age- and sex-stratified analysis showed consistent results among participants 45-54 and 55-64 years old, with no significant sex difference. This study demonstrated that higher chronic stress was significantly associated with accelerated brain aging, highlighting the importance of stress management in reducing dementia and neurodegenerative disease risks.

Comparative analysis of hemodialysis and peritoneal dialysis on the risk of new onset diabetes mellitus

BACKGROUND

Diabetes mellitus is a significant risk factor for cardiovascular events and mortality in dialysis patients. The impact of different dialysis modalities on the risk of new onset diabetes mellitus (NODM) remains a subject of debate. Previous studies did not adequately account for critical confounding factors such as pre-dialysis glycemic status, medication use, and nutritional status, which may influence the association between dialysis modality and NODM risk.

METHODS

We conducted a retrospective cohort study of 1426 non-diabetic end-stage renal disease (ESRD) patients who underwent either hemodialysis (HD) or peritoneal dialysis (PD) at a single medical center. We used different statistical methods, adjusting for potential confounding factors, and accounted for competing risk of death.

RESULTS

Over 12 years, 331 patients (23 %) developed NODM. After adjusting for potential confounding factors and mortality, PD patients had a significantly higher risk of NODM compared to HD patients (adjusted HR 1.52, p = 0.001). A propensity-matched cohort sensitivity analysis yielded similar results. Among patients with prediabetes, those receiving PD had a 2.93 times higher risk of developing NODM than those receiving HD (p for interaction <0.001), whereas no significant difference was observed among euglycemic patients. NODM was also associated with a 1.78 times increased risk of major cardiovascular events.

CONCLUSION

Our study provides evidence that PD treatment may increase the risk of NODM in ESRD patients, particularly among those with preexisting prediabetes. These findings highlight the importance of personalized treatment approaches, and nephrologists should consider prediabetes when choosing the dialysis modality for their patients.

Identifying optimal surgical approach among T1N2-3M0 non-small cell lung cancer patients: a population-based analysis

Background

Whether stage T1N2-3M0 non-small cell lung cancer (NSCLC) patients could benefit from surgery and the optimal surgical procedure have remained controversial and unclear. This study aimed to investigate whether stage T1N2-3M0 NSCLC can benefit from different surgery types and develop a tool for survival prediction.

Methods

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients diagnosed with stage T1N2-3M0 NSCLC between 2000 and 2015. A 1:1 propensity score-matched (PSM) analysis was used to balance the distribution of clinical characteristics. Survival analyses were performed by using the Kaplan-Meier (KM) curves and Cox proportional hazards regression. All patients were randomly split at a ratio of 7:3 into training and validation cohorts. The nomogram was constructed by integrating all independent predictors for overall survival (OS) and cancer-specific survival (CSS). The model's performance was evaluated by discrimination, calibration ability, and risk stratification ability.

Results

A total of 4,671 patients were enrolled. After 1:1 PSM, the distribution proportions of clinical characteristics in 1,146 patients were balanced (all P>0.05). The non-surgical approach was associated with worse survival compared with sublobectomy and lobectomy in the unmatched and matched cohorts. The multivariate Cox analysis showed that sublobectomy and lobectomy were both related to better OS and CSS rates compared with no surgery (P<0.001). Moreover, the results of subgroup analyses based on age, N stage, and radiotherapy or chemotherapy strategy were consistent. A total of 801 patients were included in the training cohort and 345 cases constituted the validation cohort. The nomogram constructed for the 1-, 3-, and 5-year OS and CSS prediction showed good discrimination, performance, and calibration both in the training and validation sets. Significant distinctions in survival curves between different risk groups stratified by prognostic scores were also observed (all P<0.001).

Conclusions

Stage T1N2-3M0 NSCLC patients could benefit from sublobectomy or lobectomy, and lobectomy provides better survival benefits. We developed and validated nomograms, which could offer clinicians instructions for strategy making.

Estimating the Effect of PrEP in Black Men Who Have Sex with Men: A Framework to Utilize Data from Multiple Non-Randomized Studies to Estimate Causal Effects

Black men who have sex with men (MSM) are disproportionately burdened by the HIV epidemic in the US. The effectiveness of pre-exposure prophylaxis (PrEP) in preventing HIV infection has been demonstrated through randomized placebo-controlled clinical trials in several populations. Importantly, no such trial has been conducted exclusively among Black MSM in the US, and it would be unethical and infeasible to do so now. To estimate the causal effects of PrEP access, initiation, and adherence on HIV risk, we utilized causal inference methods to combine data from two non-randomized studies that exclusively enrolled Black MSM. The estimated relative risks of HIV were: (i) 0.52 (95% confidence interval: 0.21, 1.22) for individuals with versus without PrEP access, (ii) 0.48 (0.12, 0.89) for individuals who initiated PrEP but were not adherent versus those who did not initiate, and (iii) 0.23 (0.02, 0.80) for individuals who were adherent to PrEP versus those who did not initiate. Beyond addressing the knowledge gap around the effect of PrEP in Black MSM in the US, which may have ramifications for public health, we have provided a framework to combine data from multiple non-randomized studies to estimate causal effects, which has broad utility.

Sequence of Epinephrine and Advanced Airway Placement After Out-of-Hospital Cardiac Arrest

Importance

While epinephrine and advanced airway management (AAM) (supraglottic airway insertion and endotracheal intubation) are commonly used for out-of-hospital cardiac arrest (OHCA), the optimal sequence of these interventions remains unclear.

Objective

To evaluate the association of the sequence of epinephrine administration and AAM with patient outcomes after OHCA.

Design, Setting, and Participants

This cohort study analyzed the nationwide, population-based OHCA registry in Japan and included adults (aged ≥18 years) with OHCA for whom emergency medical services personnel administered epinephrine and/or placed an advanced airway between January 1, 2014, and December 31, 2019. The data analysis was performed between October 1, 2022, and May 12, 2023.

Exposure

The sequence of intravenous epinephrine administration and AAM.

Main Outcomes and Measures

The primary outcome was 1-month survival. Secondary outcomes were 1-month survival with favorable functional status and prehospital return of spontaneous circulation. To control imbalances in measured patient demographics, cardiac arrest characteristics, and bystander and prehospital interventions, propensity scores and inverse probability of treatment weighting (IPTW) were performed for shockable and nonshockable initial rhythm subcohorts.

Results

Of 259 237 eligible patients (median [IQR] age, 79 [69-86] years), 152 289 (58.7%) were male. A total of 21 592 patients (8.3%) had an initial shockable rhythm, and 237 645 (91.7%) had an initial nonshockable rhythm. Using IPTW, all covariates between the epinephrine-first and AAM-first groups were well balanced, with all standardized mean differences less than 0.100. After IPTW, the epinephrine-first group had a higher likelihood of 1-month survival for both shockable (odds ratio [OR], 1.19; 95% CI, 1.09-1.30) and nonshockable (OR, 1.28; 95% CI, 1.19-1.37) rhythms compared with the AAM-first group. For the secondary outcomes, the epinephrine-first group experienced an increased likelihood of favorable functional status and prehospital return of spontaneous circulation for both shockable and nonshockable rhythms compared with the AAM-first group.

Conclusions and Relevance

These findings suggest that for patients with OHCA, administration of epinephrine before placement of an advanced airway may be the optimal treatment sequence for improved patient outcomes.

Effect of Huaier granule on prognosis of breast cancer: A single-center propensity score matching retrospective study

BACKGROUND

Huaier granule is an important medicinal fungus extract widely used in cancer treatment. Previous retrospective studies have reported its effectiveness in breast cancer patients, but the imbalanced baseline characteristics of participants could have biased the results. Therefore, this retrospective study aimed to examine the efficacy of Huaier granule on the prognosis of breast cancer patients.

METHODS

In this single-center cohort study, breast cancer patients diagnosed and treated at the Guangdong Provincial Hospital of Chinese Medicine between 2009 and 2017 were selected. The data were retrospectively analyzed and divided into two groups according to whether the patients received Huaier granules. The propensity score matching (PSM) method was used to eliminate selection bias. The disease-free survival (DFS) and overall survival (OS) for these groups were compared using the Kaplan-Meier method and the Cox regression.

RESULTS

This study included 214 early invasive breast cancer patients, 107 in the Huaier group and 107 in the control group. In the Kaplan-Meier analysis, the 2-year and 5-year DFS rates were significantly different in the Huaier group and control group (hazard ratio [HR], 0.495; 95% confidence interval [CI], 0.257-0.953; P = 0.023). The 2-year and 5-year OS rates were also significantly different (HR, 0.308; 95% CI, 0.148-0.644; P = 0.001). On multivariable Cox regression, Huaier granule was associated with improved DFS (HR, 0.440; 95% CI, 0.223-0.868; P = 0.018) and OS (HR, 0.236; 95% CI, 0.103-0.540; P = 0.001).

CONCLUSION

In this retrospective study, Huaier granules improved the DFS and OS of early invasive breast cancer patients, providing real-world evidence for further prospective studies on treating breast cancer with Huaier granules.

Effects of Low-Osmolar Contrast Media on Long-Term Renal Impairment After Coronary Angiography: Iohexol Versus Iopromide

To investigate the long-term effects of 2 commonly used low-osmolar contrast media, iohexol and iopromide, on renal function and survival in patients who underwent coronary angiography. A total of 14,141 cardiology patients from 2006 to 2013 were recruited, of whom 1,793 patients (679 patients on iohexol and 1,114 on iopromide) were evaluated for long-term renal impairment and 5,410 patients (1,679 patients on iohexol and 3,731 on iopromide) were admitted for survival analyses spanning as long as 15 years. Univariate and multivariate logistic regression were used to explore the risk factors for long-term renal impairment. Cox proportional hazard regression was used to investigate the risk factors affecting survival. Propensity score matching and inverse probability of treatment weighting were applied to balance the baseline clinical characteristics. Patients receiving iohexol demonstrated a greater occurrence of renal impairment compared with those who received iopromide. Such difference remained consistent both before and after propensity score matching or inverse probability of treatment weighting, with a statistical significance of p <0.05. Among clinical variables, receiving contrast-enhanced contrast tomography/magnetic resonance imaging during follow-up, antihypertensive medication usage, presence of proteinuria, and anemia were identified as risk factors for long-term renal impairment (p = 0.041, 0.049, 0.006, and 0.029, respectively). During survival analyses, the difference was insignificant after propensity score matching and inverse probability of treatment weighting. In conclusion, administration of iohexol was more likely to induce long-term renal impairment than iopromide, particularly among patients diagnosed with anemia and proteinuria and those taking antihypertensive medication and with additional contrast exposure. The all-cause mortality, however, showed no significant difference between iohexol and iopromide administration.

Characteristics and outcomes of patients undergoing transcatheter mitral valve replacement with the Tendyne system

BACKGROUND

Transcatheter mitral valve replacement (TMVR) has emerged as alternative to transcatheter edge-to-edge repair (TEER) for treatment of mitral regurgitation (MR); however, the role of TMVR with the Tendyne system among established treatments of MR is not well defined. We assessed characteristics and outcomes of patients treated with the Tendyne system in the current clinical practice.

METHODS

We reviewed patients who underwent cardiac computed tomography and were judged eligible for the Tendyne system.

RESULTS

A total of 63 patients were eligible for TMVR with the Tendyne system. Of these, 17 patients underwent TMVR, and 46 were treated by TEER. Patients treated with the Tendyne system were more likely to have a high transmitral pressure gradient and unsuitable mitral valve morphology for TEER than those treated with TEER. TMVR with the Tendyne system reduced the severity of MR to less than 1 + in 94.1% of the patients at discharge and achieved a greater reduction in left ventricular (LV) end-diastolic volume at the 30-day follow-up compared with TEER. In contrast, patients treated with the Tendyne system had a higher 30-day mortality than those treated with TEER, while the mortality between 30 days and one year was comparable between Tendyne and TEER.

CONCLUSIONS

Among patients eligible for the Tendyne system, approximately a quarter of the patients underwent TMVR with the Tendyne system, which led substantial reduction of MR and LV reverse remodeling than TEER. In contrast, the 30-day mortality rate was higher after TMVR with the Tendyne compared to TEER.

Artificial light at night, MRI-based measures of brain iron deposition and incidence of multiple mental disorders

BACKGROUND

Epidemiologic evidence on whether iron accumulation in brain modified the association between artificial light at night (ALAN) and incident mental disorders is lacking. The authors aims to investigate modification of brain iron deposition on the associations of ALAN with multiple mental disorders in the middle-aged and older adults.

METHODS

This prospective study used data from the UK Biobank. ALAN was drawn from satellite datasets. Susceptibility-weighted magnetic resonance imaging was used to ascertain iron content of each brain region. T2* signal loss was used as indices of iron deposition. The main outcomes are impacts of ALAN exposure on onset of wide spectrum of physician-diagnosed mental disorders, which was estimated by time-varying Cox proportional hazard model. The authors further conducted stratified analyses by levels of iron brain deposition to examine the potential modifying effects.

RESULTS

Among 298,283 participants followed for a median of 10.91 years, higher ALAN exposure was associated with increased risk of mental disorders. An IQR (11.37 nW/cm2/sr) increase in annual levels of ALAN was associated with an HR of 1.050 (95 % CI: 1.034,1.066) for any mental disorder, 1.076 (95 % CI: 1.053,1.099) for substance use disorder, and 1.036 (95 % CI: 1.004,1.069) for depression disorder in fully adjusted models. The exposure-response curves showed steeper trends at lower ALAN levels and a plateau at higher exposures. The associations were stronger in participants with high iron deposition in left hippocampus, left accumbens and left pallidum.

CONCLUSIONS

ALAN was associated with multiple mental disorders in the middle-aged and older adults, and the findings indicated stricter standards of ALAN is needed and targeted preventive measures are warranted, especially with high brain iron deposition.

Comparing the Oncologic Outcomes of Proton Therapy and Intensity-Modulated Radiation Therapy for Head and Neck Squamous Cell Carcinoma

PURPOSE

To compare the oncologic outcomes between proton therapy and intensity-modulated radiation therapy (IMRT) for head and neck squamous cell carcinoma (HNSCC) patients undergoing curative radiotherapy (RT).

EXPERIMENTAL DESIGN

We studied HNSCC patients who underwent curative-intent RT from 2015 to 2019, comparing the oncologic outcomes of proton therapy and IMRT. Our national retrospective HNSCC cohort study involved three institutes with proton therapy and 17 institutes (medical center levels) with IMRT in Taiwan. We utilized the Taiwan Cancer Registry Database to collect medical data for this study. We classified patients into two groups based on treatment method: Group 1 received IMRT, while Group 2 received proton therapy. 3:1 propensity score matching was performed to minimize the impact of potential confounders. Cox proportional hazards models were used to evaluate oncologic outcomes.

RESULTS

This study of 60,485 patients with HNSCC found that proton therapy was associated with better overall and cancer-specific survival and lower locoregional recurrence rates than IMRT. After matching, 982 patients were analyzed, with well-balanced factors. Proton therapy was a significant predictor of all-cause mortality, cancer-specific death, and locoregional recurrence (LRR). Patients who received proton therapy had significantly lower risks of all-cause mortality (adjusted hazard ratio, aHR=0.43), cancer-specific death (aHR=0.44), and LRR (aHR=0.61) than those who received IMRT.

CONCLUSION

Proton therapy is associated with superior outcomes in terms of overall survival, cancer-specific survival, and locoregional recurrence rates compared to IMRT in patients with HNSCC. These results provide valuable evidence for clinicians and patients in decision-making regarding the choice of radiation therapy for HNSCC.

Mathematical Modeling of COVID-19 Cases and Deaths and the Impact of Vaccinations during Three Years of the Pandemic in Peru

The COVID-19 pandemic has caused widespread infections, deaths, and substantial economic losses. Vaccine development efforts have led to authorized candidates reducing hospitalizations and mortality, although variant emergence remains a concern. Peru faced a significant impact due to healthcare deficiencies. This study employed logistic regression to mathematically model COVID-19's dynamics in Peru over three years and assessed the correlations between cases, deaths, and people vaccinated. We estimated the critical time (tc) for cases (627 days), deaths (389 days), and people vaccinated (268 days), which led to the maximum speed values on those days. Negative correlations were identified between people vaccinated and cases (-0.40) and between people vaccinated and deaths (-0.75), suggesting reciprocal relationships between those pairs of variables. In addition, Granger causality tests determined that the vaccinated population dynamics can be used to forecast the behavior of deaths (p-value < 0.05), evidencing the impact of vaccinations against COVID-19. Also, the coefficient of determination (R2) indicated a robust representation of the real data. Using the Peruvian context as an example case, the logistic model's projections of cases, deaths, and vaccinations provide crucial insights into the pandemic, guiding public health tactics and reaffirming the essential role of vaccinations and resource distribution for an effective fight against COVID-19.

Real-world clinical outcomes of treatment with molnupiravir for patients with mild-to-moderate coronavirus disease 2019 during the Omicron variant pandemic

It is unclear whether molnupiravir has a beneficial effect on vaccinated patients infected with the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We here evaluated the efficacy of molnupiravir in patients with mild-to-moderate coronavirus disease 2019 (COVID-19) during the Omicron variant surge in Fukushima Prefecture, Japan. We enrolled patients with mild-to-moderate COVID-19 who were admitted to hospitals between January and April, 2022. Clinical deterioration after admission was compared between molnupiravir users (n = 230) and non-users (n  = 690) after 1:3 propensity score matching. Additionally, we performed forward stepwise multivariate logistic regression analysis to evaluate the association between clinical deterioration after admission and molnupiravir treatment in the 1:3 propensity score-matched subjects. The characteristics of participants in both groups were balanced as indicated by covariates with a standardized mean difference of < 0.1. Regarding comorbidities, there was no imbalance between the two groups, except for the presence of hypertension, dyslipidemia, diabetes mellitus, and cardiac disease. The clinical deterioration rate was significantly lower in the molnupiravir users compared to the non-users (3.90% vs 8.40%; P = 0.034). Multivariate logistic regression analysis demonstrated that receiving molnupiravir was a factor for preventing deterioration (odds ratio 0.448; 95% confidence interval 0.206-0.973; P = 0.042), independent of other covariates. This real-world study demonstrates that molnupiravir contributes to the prevention of deterioration in COVID-19 patients after hospitalization during the Omicron variant phase.

Association of SGLT-2 Inhibitors With Treatment Satisfaction and Diabetes-Specific and General Health Status in Adults With Cardiovascular Disease and Type 2 Diabetes

Background It is unknown if initiation of a sodium-glucose cotransporter-2 inhibitor (SGLT-2i) is associated with changes in patient-reported health status outside of clinical trials. Methods and Results Using a prospective observational study design, adults with type 2 diabetes and cardiovascular disease were recruited from 14 US hospitals between November 2019 and December 2021 if they were new users of noninsulin antidiabetic medications. The primary outcome was change in 6-month diabetes treatment satisfaction. Secondary outcomes included diabetes-related symptom distress, diabetes-specific quality of life, and general health status for all patients and based on cardiovascular disease type. Inverse probability of treatment weight using propensity score was performed to compare outcome changes based on medication use. Of 887 patients (SGLT-2i: n=242) included in the inverse probability of treatment weight analyses, there was no difference in changes in treatment satisfaction in SGLT-2i users compared with other diabetes medication users (0.99 [95% CI, -0.14 to 2.13] versus 1.54 [1.08 to 2.00], P=0.38). Initiating an SGLT-2i versus other diabetes medications was associated with a greater reduction in ophthalmological symptoms (-3.09 [95% CI, -4.99 to -1.18] versus -0.38 [-1.54 to 0.77], P=0.018) but less improvement in hyperglycemia (1.08 [-2.63 to 4.79] versus -3.60 [-5.34 to -1.86], P=0.026). In subgroup analyses by cardiovascular disease type, SGLT-2i use was associated with a greater reduction in total diabetes symptom burden and neurological sensory symptoms in patients with heart failure. Conclusions Among patients with type 2 diabetes and cardiovascular disease, initiating an SGLT-2i was not associated with changes in diabetes treatment satisfaction, total diabetes symptoms, diabetes-specific quality of life, or general health status.

Do patients with prediabetes managed with metformin achieve better glycaemic control? A national study using primary care medical records

AIMS

To estimate the effectiveness of metformin on glycaemic parameters among participants with incident prediabetes attending Australian general practices.

METHODS

This retrospective cohort study used electronic health records of regular participants (3+ visits in two consecutive years) attending 383 Australian general practices (MedicineInsight). Participants with 'incident' prediabetes (newly recorded diagnosis between 2012 and 2017) and their glycaemic parameters (haemoglobin A1c [HbA1c] or fasting blood glucose [FBG]) at 6-, 12-, and 18-24 months post diagnosis (unexposed) or post-management with metformin (treatment) were identified from the database. We estimated the average treatment effect (ATE) of metformin management on glycaemic parameters using both linear regression and augmented inverse probability weighting.

RESULTS

Of the 4770 investigated participants with 'incident' prediabetes, 10.2% were managed with metformin. Participants on metformin had higher HbA1c levels at the baseline than those unexposed (mean 45 mmol/mol [6.2%] and 41 mmol/mol [5.9%], respectively), but no differences were observed at 6-12 months (mmol/mol ATE 0.0, 95% CI -0.4; 0.7) or 12-18 months (ATE -0.3, 95% CI -1.2; 0.3). However, participants on metformin had lower mean HbA1c mmol/mol at 18-24 months (ATE -1.1, 95% CI -2.0; 0.1) than those unexposed. Consistent results were observed for FBG (ATE at 6-12 months -0.14 [95% CI -0.25; -0.04], 12-18 months 0.02 [95% CI -0.08; 0.13] and 18-24 months -0.07 [95% CI -0.25; 0.12]).

CONCLUSION

The higher HbA1c and FBG baseline levels among participants with 'incident' prediabetes managed with metformin improved after 6-12 months of starting pharmacological management, and the effect persisted for up to 24 months. Management with metformin could prevent further deterioration of glycaemic levels.

Intra-Arterial Thrombolysis is Associated with Delayed Reperfusion of Remaining Vessel Occlusions following Incomplete Thrombectomy

BACKGROUND AND PURPOSE

Intra-arterial thrombolytics may be used to treat distal vessel occlusions, which cause incomplete reperfusion following mechanical thrombectomy. Because immediate reperfusion after intra-arterial thrombolytics occurs rarely, the aim of this study was to assess the delayed effect of intra-arterial thrombolytics using follow-up perfusion imaging.

MATERIALS AND METHODS

We included patients from a prospective stroke registry (February 2015 to September 2022) who had undergone mechanical thrombectomy and had incomplete reperfusion (expanded TICI 2a-2c) and available 24 hour perfusion imaging. Perfusion imaging was rated as delayed reperfusion if time-sensitive perfusion maps did not show wedge-shaped delays suggestive of persisting occlusions corresponding to the post-mechanical thrombectomy angiographic deficit. Patients treated with intra-arterial thrombolytics were compared with controls using multivariable logistic regression and inverse probability of treatment weighting matching for baseline differences and factors associated with delayed reperfusion.

RESULTS

The median age of the final study population (n = 459) was 74 years (interquartile range, 63-81 years), and delayed reperfusion occurred in 61% of cases. Patients treated with additional intra-arterial thrombolytics (n = 40) were younger and had worse expanded TICI scores. After matching was performed, intra-arterial thrombolytics was associated with higher rates of delayed reperfusion (adjusted OR = 2.7; 95% CI, 1.1-6.4) and lower rates of new infarction in the residually hypoperfused territory after mechanical thrombectomy (adjusted OR = 0.3; 95% CI, 0.1-0.7). No difference was found in the rates of functional independence (90-day mRS, 0-2; adjusted OR = 1.4; 95% CI, 0.4-4.1).

CONCLUSIONS

Rescue intra-arterial thrombolytics is associated with delayed reperfusion of remaining vessel occlusions following incomplete mechanical thrombectomy. The value of intra-arterial thrombolytics as a potential therapy for incomplete reperfusions after mechanical thrombectomy should be assessed in the setting of randomized controlled trials.

Causal inference indicates that poor responders have similar outcomes with the antagonist protocol compared with flare

OBJECTIVE

To use causal inference to investigate whether the flare or antagonist protocol is better for poor responders going through controlled ovarian stimulation.

DESIGN

A retrospective study.

SETTING

Retrieval cycles from the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System.

PATIENTS

Patients in the United States underwent autologous in vitro fertilization cycles from 2014 to 2019 using either the flare or antagonist protocol.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURE

Primary outcomes included oocytes retrieved, fertilized oocytes (2PNs), blastocysts, the cumulative live birth rate (CLBR), and cycle cancelation rate.

RESULTS

After propensity score matching, patients with a predicted poor response (antimüllerian hormone, <0.5) on their first in vitro fertilization cycle had similar outcomes on the antagonist protocol (CLBR of 14.2%, 95% confidence intervals [CIs]: 13.6%, 14.8%) compared with flare (CLBR of 13.6%, 95% CIs: 12.4%, 14.8%). We evaluated patients undergoing a second cycle after having a poor response (<4 oocytes retrieved) on their first cycle. Patients in the antagonist-to-antagonist group had a similar change in outcomes between the first and second cycles (average CLBR improvement of 13.9%, 95% CIs: 12.1%, 15.6%) compared with the antagonist-to-flare group (average CLBR improvement of 14.4%, 95% CIs: 10.9%, 18.3%). In addition, patients in the flare-to-antagonist group had a similar change in outcomes between the first and second cycles (average CLBR improvement of 10.4%, 95% CIs: 6.6%, 14.5%) compared with the flare-to-flare group (average CLBR improvement of 9.0%, 95% CIs: 5.1%, 13.4%).

CONCLUSION

Poor responders have similar outcomes on an antagonist protocol compared with a flare protocol for both the first and second cycles.

Propensity Scores in Health Disparities Research: The Example of Cognitive Aging and the Hispanic Paradox

BACKGROUND

Individuals of Mexican ancestry in the United States experience substantial socioeconomic disadvantages compared with non-Hispanic white individuals; however, some studies show these groups have similar dementia risk. Evaluating whether migration selection factors (e.g., education) associated with risk of Alzheimer disease and related dementia (ADRD) explain this paradoxical finding presents statistical challenges. Intercorrelation of risk factors, common with social determinants, could make certain covariate patterns very likely or unlikely to occur for particular groups, which complicates their comparison. Propensity score (PS) methods could be leveraged here to diagnose nonoverlap and help balance exposure groups.

METHODS

We compare conventional and PS-based methods to examine differences in cognitive trajectories between foreign-born Mexican American, US-born Mexican American, and US-born non-Hispanic white individuals in the Health and Retirement Study (1994-2018). We examined cognition using a global measure. We estimated trajectories of cognitive decline from linear mixed models adjusted for migration selection factors also associated with ADRD risk conventionally or with inverse probability weighting. We also employed PS trimming and match weighting.

RESULTS

In the full sample, where PS overlap was poor, unadjusted analyses showed both Mexican ancestry groups had worse baseline cognitive scores but similar or slower rates of decline compared with non-Hispanic white adults; adjusted findings were similar, regardless of method. Focusing analyses on populations where PS overlap was improved (PS trimming and match weighting) did not alter conclusions.

CONCLUSIONS

Attempting to equalize groups on migration selection and ADRD risk factors did not explain paradoxical findings for Mexican ancestry groups in our study.

Incidence of Surgical Site Infection Following Lateral Lumbar Interbody Fusion Compared With Posterior/Transforaminal Lumbar Interbody Fusion: A Propensity Score-Weighted Study

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The objective of this study was to compare the incidence of surgical site infection (SSI) after lateral lumbar interbody fusion (LLIF) and posterior/transforaminal lumbar interbody fusion ( P /TLIF).

SUMMARY OF BACKGROUND DATA

Previous studies have shown that LLIF can improve neurological symptoms to a comparable degree to P /TLIF. However, data on the risk of SSI after LLIF is lacking compared with P /TLIF.

MATERIALS AND METHODS

The study was conducted under a retrospective cohort design in patients undergoing LLIF or P /TLIF for lumbar degenerative diseases between 2013 and 2020 using a hospital administrative database. We used propensity score overlap weighting to adjust for confounding factors including age, sex, body mass index, comorbidities, number of fusion levels, hospital size, and surgery year. We estimated weighted odds ratios (ORs) and 95% CIs for SSI within 30 days postoperatively.

RESULTS

We compared the risk of SSI between 2874 patients who underwent LLIF and 24,245 patients who received P/TLIF Patients who had received LLIF were at significantly less risk of experiencing an SSI compared with those receiving P/TLIF (0.7% vs. 1.2%; weighted OR: 0.57; 95% CI: 0.36 -0.92; P=0.02). As a secondary outcome, patients who had received LLIF had less risk of transfusion (7.8% vs. 11.8%; weighted OR: 0.63; 95% CI:0.54 -0.73; P <0.001).

CONCLUSIONS

In this large retrospective cohort study of adults undergoing lumbar interbody fusion, LLIF was associated with a significantly lower risk of SSI than P /TLIF. The small, but significantly, decreased risk of SSI associated with LLIF may inform decisions regarding the technical approach for lumbar interbody fusion.

Metformin and Cancer: Solutions to a Real-World Evidence Failure

The quest to repurpose metformin, an antidiabetes drug, as an agent for cancer prevention and treatment, which began in 2005 with an observational study that reported a reduction in cancer incidence among metformin users, generated extensive experimental, observational, and clinical research. Experimental studies revealed that metformin has anticancer effects via various pathways, potentially inhibiting cancer cell proliferation. Concurrently, multiple nonrandomized observational studies reported remarkable reductions in cancer incidence and outcomes with metformin use. However, these studies were shown, in 2012, to be affected by time-related biases, such as immortal time bias, which tend to greatly exaggerate the benefit of a drug. The observational studies that avoided these biases did not find an association. Subsequently, the randomized trials of metformin for the treatment of type 2 diabetes and as adjuvant therapy for the treatment of various cancers, advanced or metastatic, did not find reductions in cancer incidence or outcomes. Most recently, the largest phase 3 randomized trial of metformin as adjuvant therapy for breast cancer, which enrolled 3,649 women with a 5-year follow-up, found no benefit for disease-free survival or overall survival with metformin. This major failure of observational real-world evidence studies in correctly assessing the effects of metformin on cancer incidence and outcomes was caused by preventable biases which, surprisingly, are still prominent in 2022. Rigorous approaches for observational studies that emulate randomized trials, such as the incident and prevalent new-user designs along with propensity scores, avoid these biases and can provide more accurate real-world evidence for the repurposing of drugs such as metformin.

Extensive Intraductal Component in Breast Cancer: What Role in Disease-Free Survival?

INTRODUCTION

Extensive intraductal component (EIC) associated to early breast cancer could increase the risk locoregional recurrence, but its impact on distant metastases is still unclear. The aim of the present study was to assess the role of EIC on 5-year survival outcomes in patients affected by early breast cancer treated with breast-conserving surgery.

METHODS

A total of 414 consecutive patients with a minimum follow-up of 60 mo were collected from January 2007 to December 2015. Disease-free survival (DFS), distant metastasis-free survival (DMFS), and locoregional recurrence-free survival at 5 y were assessed considering the presence or absence of EIC and other clinical and pathological features.

RESULTS

Absence of EIC was independently associated with worse 5-year DFS (hazard ratio [HR] 1.68, P = 0.008) and 5-year DMFS (HR 1.93, P = 0.007), whereas 5-year locoregional recurrence-free survival was not affected (HR 1.50, P = 0.16). Five-year DFS was increased by EIC in T1 patients (P = 0.03) but not in T2 stage. Moreover, EIC was associated to better DFS in G2 (P = 0.03) and G3 patients (P = 0.01) but not in G1 cases.

CONCLUSIONS

Our results suggest that EIC is independently correlated with increased 5-year DFS and in particular with 5-year DMFS.

Association of health literacy with short-term postoperative outcomes in older adult patients with abdominal tumors undergoing surgery and perioperative rehabilitation program: A prospective cohort study

INTRODUCTION

Low health literacy (HL) is associated with poor surgical outcomes in patients with abdominal tumors, despite enhanced recovery programs. However, the relationship between HL and postoperative outcomes, including health-related quality of life (HRQOL) and physical functions, has been unclear in patients with abdominal tumors receiving perioperative rehabilitation programs (PRPs). Our objective was to identify associations of HL with postoperative functional and general outcomes in patients with abdominal tumors undergoing surgery and PRPs, controlling for critical covariates.

MATERIALS AND METHODS

The prospective cohort study was conducted from April 2020 to December 2021 in a single acute care hospital in Akita City, Japan. Out of 112 consecutive older adults with abdominal tumors referred to PRPs before surgery for tumors, 101 participated. Three patients declined undergoing follow-up assessment, and thus 97 were analyzed. Demographic data, comorbidities, education, surgical procedure, frailty status, cognitive functions, physical activity, nutritional status, tumor sites, types, and stages were collected as covariates at baseline. All participants underwent PRPs. HL was measured using the Japanese version of the European Health Literacy Survey Questionnaire, a comprehensive HL measurement. Primary endpoints were changes in HRQOL, measured using the EuroQol 5-dimension 5-level (EQ-5D-5L) index and EuroQol-visual analog scale (EQ-VAS), and physical functions (chair-stand ability, usual gait speed, and grip strength) from before surgery to discharge. Secondary endpoints were 90-day readmissions, postoperative complications, and length of hospital stay. Multivariate regression with inverse probability weighting, using propensity scores, estimeted associations of HL with the outcomes.

RESULTS

Of the 97 patients (36 [37.1%] women, mean [standard deviation] age 74.4 [6.3] years), 42 (43.3%) reported low HL. At baseline, patients with low HL exhibited worse EQ-5D-5L scores (P = .001), EQ-VAS values (P = .03), chair-stand ability (P = .001), and gait speed (P = .03) than controls. Low HL was associated with a low risk of grip strength declines (risk ratio, 0.13; 95% confidence interval, 0.12-0.99) but not with any other outcome.

DISCUSSION

There appeared to be no apparent associations of HL with surgical outcomes in patients with abdominal tumors receiving PRPs. Thus, HL might not be a crucial predictor of surgical outcomes when combined with PRPs.

Association of statin use with outcomes of patients admitted with COVID-19: an analysis of electronic health records using superlearner

IMPORTANCE

Statin use prior to hospitalization for Coronavirus Disease 2019 (COVID-19) is hypothesized to improve inpatient outcomes including mortality, but prior findings from large observational studies have been inconsistent, due in part to confounding. Recent advances in statistics, including incorporation of machine learning techniques into augmented inverse probability weighting with targeted maximum likelihood estimation, address baseline covariate imbalance while maximizing statistical efficiency.

OBJECTIVE

To estimate the association of antecedent statin use with progression to severe inpatient outcomes among patients admitted for COVD-19.

DESIGN, SETTING AND PARTICIPANTS

We retrospectively analyzed electronic health records (EHR) from individuals ≥ 40-years-old who were admitted between March 2020 and September 2022 for ≥ 24 h and tested positive for SARS-CoV-2 infection in the 30 days before to 7 days after admission.

EXPOSURE

Antecedent statin use-statin prescription ≥ 30 days prior to COVID-19 admission.

MAIN OUTCOME

Composite end point of in-hospital death, intubation, and intensive care unit (ICU) admission.

RESULTS

Of 15,524 eligible COVID-19 patients, 4412 (20%) were antecedent statin users. Compared with non-users, statin users were older (72.9 (SD: 12.6) versus 65.6 (SD: 14.5) years) and more likely to be male (54% vs. 51%), White (76% vs. 71%), and have ≥ 1 medical comorbidity (99% vs. 86%). Unadjusted analysis demonstrated that a lower proportion of antecedent users experienced the composite outcome (14.8% vs 19.3%), ICU admission (13.9% vs 18.3%), intubation (5.1% vs 8.3%) and inpatient deaths (4.4% vs 5.2%) compared with non-users. Risk differences adjusted for labs and demographics were estimated using augmented inverse probability weighting with targeted maximum likelihood estimation using Super Learner. Statin users still had lower rates of the composite outcome (adjusted risk difference: - 3.4%; 95% CI: - 4.6% to - 2.1%), ICU admissions (- 3.3%; - 4.5% to - 2.1%), and intubation (- 1.9%; - 2.8% to - 1.0%) but comparable inpatient deaths (0.6%; - 1.3% to 0.1%).

CONCLUSIONS AND RELEVANCE

After controlling for confounding using doubly robust methods, antecedent statin use was associated with minimally lower risk of severe COVID-19-related outcomes, ICU admission and intubation, however, we were not able to corroborate a statin-associated mortality benefit.

Chemoprophylactic Anticoagulation Following Lumbar Surgery Significantly Reduces Thromboembolic Events After Instrumented Fusions, Not Decompressions

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To quantify any reduction in venous thromboembolic events (VTEs) caused by chemoprophylaxis among lumbar surgery patients.

SUMMARY OF BACKGROUND DATA

Chemoprophylactic anticoagulation (chemoprophylaxis) is used to prevent VTE after lumbar surgery. However, the treatment effect of chemoprophylaxis has not been reported among spine surgery patients, as conventional statistical methods preclude such inferences.

MATERIALS AND METHODS

A total of 1243 consecutive lumbar fusions and 1433 noninstrumented lumbar decompressions performed at our institution over a six-year period were identified, and clinical and demographic data were collected, including on VTE events within 30 days postoperatively. Instrumented lumbar fusions and noninstrumented lumbar surgeries were analyzed separately. Patients who were given chemoprophylaxis (treatment) and controls were matched according to known VTE risk factors, including age, body mass index, sex, diabetes, chronic kidney disease, history of VTE, estimated blood loss, length of surgery, transfusion, whether surgery was staged, and whether surgery used an anterior approach. K-nearest neighbor propensity score matching was performed, and the treatment effect of chemoprophylaxis was calculated.

RESULTS

Unadjusted, there was no difference in the rate of VTE between treatment and controls in either population. Baseline clinical and demographic characteristics differed significantly between treatment and control groups. In all, 575 lumbar fusion patients and 435 noninstrumented lumbar decompression patients were successfully propensity score matched, yielding balanced models (Rubin B <25, 0.5<Rubin R <2.0) and >60% reduction in known bias for both populations. The treatment effect of chemoprophylaxis after lumbar fusion in our patient population was a reduction in VTE incidence from 9.4% to 4.2% ( P <0.05), and propensity score adjusted regression confirmed a reduced odds of VTE with chemoprophylaxis (odds ratio=0.37, P =0.035). The treatment effect was not significant for noninstrumented lumbar decompression patients.

CONCLUSION

Among patients undergoing instrumented lumbar fusions, chemoprophylactic anticoagulation causes a significant reduction in VTE, but causes no significant reduction among patients undergoing noninstrumented lumbar decompression.

Clinical Outcomes of First Subsequent Therapies After Abiraterone Acetate Plus Prednisone for High-Risk Metastatic Castration-Sensitive Prostate Cancer in the LATITUDE Study

BACKGROUND

Abiraterone acetate plus prednisone with androgen deprivation therapy is a standard treatment option for patients with high-risk metastatic castration-sensitive prostate cancer (mCSPC). However, no data are available on the optimal subsequent treatment option in patients treated with abiraterone acetate plus prednisone for high-risk mCSPC.

OBJECTIVE

We aimed to compare the clinical outcomes of subsequent therapy after discontinuation of abiraterone acetate plus prednisone in patients with high-risk mCSPC.

METHODS

Overall survival and time to treatment failure from initiation of subsequent therapies were estimated by applying a marginal structural Cox proportional hazards model using inverse probability of treatment weighting with a change of time scale to time on treatment.

RESULTS

A total of 217 patients received subsequent therapies: 127 received chemotherapy, 49 received non-chemotherapy, and 41 received other treatments. For overall survival, when adjusted with the marginal structural Cox proportional hazards model using inverse probability of treatment weighting, the hazard ratio was 1.212 (95% confidence interval [CI] 0.742-1.979) for chemotherapy versus non-chemotherapy, 0.534 (95% CI 0.267-1.066) for non-chemotherapy versus other treatments, and 0.635 (95% CI 0.317-1.271) for chemotherapy versus other treatments. For time to treatment failure, the hazard ratio was 1.287 (95% CI 0.832-1.989) for chemotherapy versus non-chemotherapy, 0.785 (95% CI 0.486-1.269) for non-chemotherapy versus other treatments, and 0.898 (95% CI 0.612-1.318) for chemotherapy versus other treatments.

CONCLUSIONS

No differences were observed between the treatment effects of chemotherapy and non-chemotherapy in patients with high-risk mCSPC after abiraterone acetate plus prednisone. These findings suggest that life-extending subsequent therapy after abiraterone acetate plus prednisone for mCSPC should be chosen at the physician's discretion and patient's preference.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT01715285, registered 26 October, 2012.

Applications of propensity score matching: a case series of articles published in Annals of Coloproctology

Propensity score matching (PSM) is an increasingly applied method of ensuring comparability between groups of interest. However, PSM is often applied unconditionally, without precise considerations. The purpose of this study is to provide a nonmathematical guide for clinicians at the stage of designing a PSM-based study. We provide a seed of thought for considering whether applying PSM would be appropriate and, if so, the scope of the list of variables. Although PSM may be simple, its results could vary substantially according to how the propensity score is constructed. Misleading results can be avoided through a critical review of the process of PSM.

Allogeneic Red Blood Cell Transfusion and Infectious Complications Following Pediatric Spinal Fusion: NSQIP-P Analysis

Substantial bleeding occurs during spinal fusion surgery in the pediatric population, and many patients receive allogeneic red blood cell transfusion (ARBT) for the treatment of resulting perioperative anemia. ARBT is thought to increase vulnerability to postoperative infections following major surgical procedures, but studies of this relationship in children undergoing spinal fusion have yielded conflicting results.

Theory and practice of propensity score analysis

Propensity score analysis has been widely used in observational studies to make a causal inference. This study introduces three assumptions for causal inferences-conditional exchangeability, positivity, and consistency-and five steps for propensity score (PS) analysis-1) construct appropriate PS models, 2) check overlap in PS, 3) apply appropriate weighting (inverse probability of treatment weighting, standardized mortality ratio weighting, matching weights, and overlap weights) or matching methods according to the target of inference, 4) check the balance of covariates, and 5) estimate the effect of exposure appropriately. Finally, the advantages of PS analyses over conventional multivariable regression are discussed.

Two-stage matching-adjusted indirect comparison

BACKGROUND

Anchored covariate-adjusted indirect comparisons inform reimbursement decisions where there are no head-to-head trials between the treatments of interest, there is a common comparator arm shared by the studies, and there are patient-level data limitations. Matching-adjusted indirect comparison (MAIC), based on propensity score weighting, is the most widely used covariate-adjusted indirect comparison method in health technology assessment. MAIC has poor precision and is inefficient when the effective sample size after weighting is small.

METHODS

A modular extension to MAIC, termed two-stage matching-adjusted indirect comparison (2SMAIC), is proposed. This uses two parametric models. One estimates the treatment assignment mechanism in the study with individual patient data (IPD), the other estimates the trial assignment mechanism. The first model produces inverse probability weights that are combined with the odds weights produced by the second model. The resulting weights seek to balance covariates between treatment arms and across studies. A simulation study provides proof-of-principle in an indirect comparison performed across two randomized trials. Nevertheless, 2SMAIC can be applied in situations where the IPD trial is observational, by including potential confounders in the treatment assignment model. The simulation study also explores the use of weight truncation in combination with MAIC for the first time.

RESULTS

Despite enforcing randomization and knowing the true treatment assignment mechanism in the IPD trial, 2SMAIC yields improved precision and efficiency with respect to MAIC in all scenarios, while maintaining similarly low levels of bias. The two-stage approach is effective when sample sizes in the IPD trial are low, as it controls for chance imbalances in prognostic baseline covariates between study arms. It is not as effective when overlap between the trials' target populations is poor and the extremity of the weights is high. In these scenarios, truncation leads to substantial precision and efficiency gains but induces considerable bias. The combination of a two-stage approach with truncation produces the highest precision and efficiency improvements.

CONCLUSIONS

Two-stage approaches to MAIC can increase precision and efficiency with respect to the standard approach by adjusting for empirical imbalances in prognostic covariates in the IPD trial. Further modules could be incorporated for additional variance reduction or to account for missingness and non-compliance in the IPD trial.

Guideline-directed medical therapy after transcatheter edge-to-edge mitral valve repair

Objective

A sizeable proportion of patients with secondary mitral regurgitation (SMR) do not receive guideline-directed medical therapy (GDMT) for heart failure (HF). We investigated the association between the use of GDMT and mortality in patients with SMR who underwent transcatheter edge-to-edge repair (TEER).

Methods

We retrospectively analysed patients with SMR and a left ventricular ejection fraction of <50% who underwent TEER at three centres. According to current HF guidelines, GDMT was defined as triple therapy consisting of beta-blockers, renin–angiotensin system (RAS) inhibitors and mineralocorticoid receptor antagonists (MRAs). Patients were divided into two groups: GDMT and non-GDMT groups. We calculated the propensity scores and carried out inverse probability of treatment weighting (IPTW) analyses to compare 2-year mortality between the two groups.

Results

Of 463 patients, 228 (49.2%) were treated with GDMT upon discharge. IPTW-adjusted Kaplan-Meier curve showed patients with GDMT had a lower incidence of mortality than those without GDMT (19.8% vs 31.1%, p=0.011). In IPTW-adjusted Cox proportional hazards analysis, GDMT was associated with a reduced risk of 2-year mortality (HR: 0.58; 95% CI: 0.35 to 0.95; p=0.030), which was consistent among clinical subgroups. Moreover, patients with GDMT had a higher rate of left ventricular reverse remodelling at 1 year after TEER than those without GDMT.

Conclusion

GDMT, defined as triple therapy consisting of beta-blockers, RAS inhibitors and MRAs, was associated with a reduced risk of 2-year mortality after TEER for SMR. Optimisation of medical therapy is crucial to improve clinical outcomes in patients undergoing TEER for SMR.

Real-world clinical outcomes of treatment with casirivimab-imdevimab among patients with mild-to-moderate coronavirus disease 2019 during the Delta variant pandemic

Background: Mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may reduce the efficacy of neutralizing monoclonal antibody therapy against coronavirus disease 2019 (COVID-19). We here evaluated the efficacy of casirivimab-imdevimab in patients with mild-to-moderate COVID-19 during the Delta variant surge in Fukushima Prefecture, Japan. Methods: We enrolled 949 patients with mild-to-moderate COVID-19 who were admitted to hospital between July 24, 2021 and September 30, 2021. Clinical deterioration after admission was compared between casirivimab-imdevimab users (n = 314) and non-users (n = 635). Results: The casirivimab-imdevimab users were older (P < 0.0001), had higher body temperature (≥ 38°C) (P < 0.0001) and greater rates of history of cigarette smoking (P = 0.0068), hypertension (P = 0.0004), obesity (P < 0.0001), and dyslipidemia (P < 0.0001) than the non-users. Multivariate logistic regression analysis demonstrated that receiving casirivimab-imdevimab was an independent factor for preventing deterioration (odds ratio 0.448; 95% confidence interval 0.263-0.763; P = 0.0023). Furthermore, in 222 patients who were selected from each group after matching on the propensity score, deterioration was significantly lower among those receiving casirivimab-imdevimab compared to those not receiving casirivimab-imdevimab (7.66% vs 14.0%; p = 0.021). Conclusion: This real-world study demonstrates that casirivimab-imdevimab contributes to the prevention of deterioration in COVID-19 patients after hospitalization during a Delta variant surge.

Risks of Comorbidities in Patients With Palmoplantar Pustulosis vs Patients With Psoriasis Vulgaris or Pompholyx in Korea

Importance

Palmoplantar pustulosis (PPP) has been reported to be accompanied by systemic conditions. However, the risks of comorbidities in patients with PPP have rarely been evaluated.

Objective

To assess the risks of comorbidities in patients with PPP compared with patients with psoriasis vulgaris or pompholyx.

Design, Setting, and Participants

This nationwide population-based cross-sectional study used data from the Korean National Health Insurance database and the National Health Screening Program collected from January 1, 2010, to December 31, 2019. Data were analyzed from July 1, 2020, to October 31, 2021. Korean patients diagnosed with PPP, psoriasis vulgaris, or pompholyx who visited a dermatologist between January 1, 2010, and December 31, 2019, were enrolled.

Exposures

Presence of PPP.

Main Outcomes and Measures

The risks of comorbidities among patients with PPP vs patients with psoriasis vulgaris or pompholyx were evaluated using a multivariable logistic regression model.

Results

A total of 37 399 patients with PPP (mean [SD] age, 48.98 [17.20] years; 51.7% female), 332 279 patients with psoriasis vulgaris (mean [SD] age, 47.29 [18.34] years; 58.7% male), and 365 415 patients with pompholyx (mean [SD] age, 40.92 [17.63] years; 57.4% female) were included in the analyses. Compared with patients with pompholyx, those with PPP had significantly higher risks of developing psoriasis vulgaris (adjusted odds ratio [aOR], 72.96; 95% CI, 68.19-78.05; P < .001), psoriatic arthritis (aOR, 8.06; 95% CI, 6.55-9.92; P < .001), ankylosing spondylitis (aOR, 1.91; 95% CI, 1.61-2.27; P < .001), type 1 diabetes (aOR, 1.33; 95% CI, 1.16-1.52; P < .001), type 2 diabetes (aOR, 1.33; 95% CI, 1.29-1.38; P < .001), Graves disease (aOR, 1.25; 95% CI, 1.11-1.42; P < .001), Crohn disease (aOR, 1.63; 95% CI, 1.11-2.40; P = .01), and vitiligo (aOR, 1.87; 95% CI, 1.65-2.12; P < .001) after adjusting for demographic covariates. The risks of ankylosing spondylitis (aOR, 1.37; 95% CI, 1.16-1.62; P < .001) and Graves disease (aOR, 1.40; 95% CI, 1.23-1.58; P < .001) were significantly higher among patients with PPP vs psoriasis vulgaris. However, the risks of psoriatic arthritis (aOR, 0.54; 95% CI, 0.47-0.63; P < .001), systemic lupus erythematosus (aOR, 0.67; 95% CI, 0.46-0.97; P = .04), Sjögren syndrome (aOR, 0.70; 95% CI, 0.50-0.96; P = .03), systemic sclerosis (aOR, 0.29; 95% CI, 0.11-0.77; P = .01), vitiligo (aOR, 0.53; 95% CI, 0.47-0.60; P < .001), and alopecia areata (aOR, 0.88; 95% CI, 0.81-0.95; P = .001) were significantly lower among those with PPP vs psoriasis vulgaris.

Conclusions and Relevance

The results of this cross-sectional study suggest that patients with PPP have an overlapping comorbidity profile with patients with psoriasis vulgaris but not patients with pompholyx. However, the risks of comorbidities among patients with PPP may be substantially different from those among patients with psoriasis vulgaris.

General health checks and incident dementia: A six-year follow-up study of community-dwelling older adults in Japan

General health checks to detect cardiovascular risk factors form part of routine health care in many countries. Cardiovascular disease and dementia share a number of risk factors; however it remains unclear whether general health checks can reduce the incidence of dementia. We used longitudinal data from the Japan Gerontological Evaluation Study with up to 6.4 years follow-up (from 2010 to 2016). A total of 31,012 disability-free adults aged 65-74 were included. The outcome variable was dementia onset certified under the national long-term care insurance system. The treatment variable was defined as having health checks within the past 12 months prior to the baseline survey in 2010. After multiple imputation, we performed propensity score matching (PSM) to exclude off-support individuals who were the least likely to have health checks. We also performed inverse probability treatment weighting (IPTW) to estimate the effect of the treatment if everyone within the population was compliant to health checks. The hazard ratios for dementia onset among those reporting health checks within the previous year was 0.89 (95% confidence interval (CI): 0.78, 1.02) in the PSM analysis and 0.84 (95% CI: 0.75, 0.95) in the IPTW analysis. We then estimated the effect of health checks on 5-year incident dementia. The 5-year cumulative incidence difference based on the PSM analysis was -0.0046 (95%CI: -0.0101, 0.0009), while that based on the IPTW analysis was -0.0046 (95%CI, -0.0090, -0.0002). The PSM and IPTW approaches yielded similar findings that the incidence of dementia was lower among people having health checks.

Being left alone at home and dental caries of children aged 6-7 years

BACKGROUND

Leaving children alone at home is considered child neglect in some countries but is not prohibited in Japan. We investigated the association between being left alone at home and dental caries of children aged 6-7 years in Japan.

METHOD

The data on first graders in all 69 public elementary schools in Adachi, Tokyo, obtained from repeated cross-sectional surveys in 2015, 2017, and 2019 were analyzed. Caregivers answered the questionnaire, and the data were linked to the information on children's dental caries evaluated in school dental health checkups (N = 12,029). Poisson regression analysis with propensity score matching (PSM) was applied to account for confounders.

RESULTS

Leaving children alone at home for ≥1 hour during the weekdays was reported by 46.4% of the caregivers, which did not vary across years. The PSM analysis showed that, compared with children never being left alone at home, children being left alone at home for ≥1 time per week had more dental caries (mean ratio (MR) 1.11; 95% confidence interval (CI), 1.02-1.21; P-value 0.016), while <1 time per week was not associated (MR 0.97; 95% CI, 0.92-1.03; P-value 0.345). The difference between those being left alone at home for <1 time per week and those being left alone for ≥1 time per week was not significant after applying Bonferroni correction (MR 1.12; 95% CI, 1.00-1.26; P-value 0.041).

CONCLUSION

Leaving children alone at home for ≥1 hour every week might be a risk factor for dental caries of children aged 6-7 years.