Estimating the effect of diuretics and inhaled corticosteroids for evolving bronchopulmonary dysplasia in preterm infants

BACKGROUND

Off-label treatment of extremely preterm infants with diuretics and inhaled corticosteroids (ICS) for evolving bronchopulmonary dysplasia (BPD) is common. Their effectiveness in reducing mortality or BPD severity, and optimal treatment timing, are unclear.

OBJECTIVES

To determine whether diuretic treatment or ICS administration for infants with early evolving (between 10-27 days postnatal) and progressively evolving (28th-day-36th-week postnatal) BPD are independently associated with reduced mortality and moderate or severe BPD at 36-weeks postmenstrual age (PMA).

METHODS

We examined neonates born before 28 weeks' gestation and admitted to neonatal intensive care units on postnatal Day 0 between 2006 and 2016 using data collected during routine care recorded within the Paediatric Health Information System (PHIS). An early evolving BPD cohort consisted of infants treated with oxygen, positive pressure or mechanical ventilation at 10 days postnatal. The progressively evolving BPD cohort consisted of infants treated with these modalities at 28 days. In new users, we evaluated the effect of diuretic and ICS treatment on mortality or BPD severity at 36 weeks PMA, adjusting for time-dependent confounding by respiratory status using marginal structural models.

RESULTS

Early evolving BPD was present in 10,135 patients; progressively evolving BPD in 11,728. New diuretic exposure during early evolving BPD (adjusted risk ratio [aRR] 0.77, 95% confidence interval [CI] 0.65, 0.93) was associated with decreased mortality or moderate/severe BPD risk. New diuretics (aRR 0.86, 95% CI 0.75, 0.99) during progressively evolving BPD between 28-days-36-weeks PMA were less strongly associated with mortality or moderate/severe BPD reduction. There was no strong association for ICS in patients with early evolving (aRR: 1.40; 95% CI: 0.79, 2.51) or progressively evolving BPD (aRR 1.16, 95% CI 0.95, 1.49).

CONCLUSION

Diuretics, but not ICS, for evolving BPD were associated with mortality and BPD risk reduction.

Prospective longitudinal relations among frequent social media use, nicotine vaping and experiencing internalizing mental health problems

AIMS

To compare four a priori rival mediated pathways of frequent social media use, electronic nicotine delivery systems (ENDS) use and internalizing mental health (MH) problems across five waves of nationally representative data.

DESIGN, SETTING AND PARTICIPANTS

This was a longitudinal study using data drawn from waves 2-5 (October 2014-November 2019) of the Population Assessment of Tobacco and Health Study, a nationally representative cohort study spanning approximately 5 years, conducted in the United States. The analytical sample of participants included those who were aged 12-14 years at wave 2 and who provided data in subsequent waves until wave 4.5 (n = 4627, 69.7% were White and 51.4% were male).

MEASUREMENTS

Frequent social media use (several times a day), ENDS use (past 30-day use) and internalizing MH problems (endorsed symptoms on four items in the past year) were dichotomized for analysis.

FINDINGS

The weighted proportions of the three key variables increased over time. From wave 2 to wave 5, frequent social media use grew from 56.9 to 77.2%; internalizing MH problems from 18.9 to 29.0%; and ENDS use from 1.4 to 11.4%. In weighted logistic regressions using generalized linear mixed models with random effects, there was a significant within-person association between frequent social media use at time t and greater ENDS use at t + 1 [adjusted odds ratio (aOR) = 1.87; 95% confidence interval (CI) = 1.47, 2.37] and worsened internalizing MH problems at t + 1 (aOR = 1.19; 95% CI = 1.04, 1.37). A model-based causal mediation analysis and marginal structural models were fitted to estimate the average causal mediation effect. Among all four examined mediation pathways throughout the three constructs, partial mediation was observed, and all the pathways were significant for both boys and girls. Sex differences did not emerge in the examined prospective mediated pathways.

CONCLUSIONS

Among youth in the United States, frequent social media use appears to mediate the prospective association between experiencing internalizing mental health problems and using electronic nicotine delivery systems.

Sodium-glucose cotransporter-2 inhibitors for hypergycemia in phosphoinositide 3-kinase pathway inhibition

PURPOSE

Phosphoinositide 3-kinase (PI3K) inhibition is used for the treatment of certain cancers, but can cause profound hyperglycemia and insulin resistance, for which sodium-glucose cotransporter-2 (SGLT2) inhibitors have been proposed as a preferred therapy. The objective of this research is to assess the effectiveness and safety of SGLT2 inhibitors for hyperglycemia in PI3K inhibition.

METHODS

We conducted a single-center retrospective review of adults initiating the PI3K inhibitor alpelisib. Exposure to different antidiabetic drugs and adverse events including diabetic ketoacidosis (DKA) were assessed through chart review. Plasma and point-of-care blood glucoses were extracted from the electronic medical record. Change in serum glucose and the rate of DKA on SGLT2 inhibitor versus other antidiabetic drugs were examined as co-primary outcomes.

RESULTS

We identified 103 patients meeting eligibility criteria with median follow-up of 92 days after starting alpelisib. When SGLT2 inhibitors were used to treat hyperglycemia, they were associated with a decrease in mean random glucose by -46 mg/dL (95% CI - 77 to - 15) in adjusted linear modeling. Five cases of DKA were identified, two occurring in patients on alpelisib plus SGLT2 inhibitor. Estimated incidence of DKA was: alpelisib plus SGLT2 inhibitor, 48 DKA cases per 100 patient-years (95% CI 6, 171); alpelisib with non-SGLT2 inhibitor antidiabetic drugs, 15 (95% CI 2, 53); alpelisib only, 4 (95% CI 0.1, 22).

CONCLUSIONS

SGLT2 inhibitors are effective treatments for hyperglycemia in the setting of PI3K inhibition.

Phosphodiesterase-5 Inhibitors and Dementia Risk: Confounding by Indication in Real-World Studies

Pharmacoepidemiologic studies using routinely collected data allow researchers to propose drugs for repurposing trials for dementia prevention or treatment. A recent cohort study reported a 54% lower dementia risk among users of sildenafil compared to users of certain cardiovascular medications. We caution that "confounding by indication" can arise when outcomes are compared between a drug of interest and an inappropriate comparator. Here, we emphasize important considerations in selecting an active comparator. We assess the implications of substantial risk of confounding by indication in pharmacoepidemiologic studies linking phosphodiesterase-5 inhibitors to lower dementia risk.

Effects of a clinic-based reproductive empowerment intervention on proximal outcomes of contraceptive use, self-efficacy, attitudes, and awareness and use of survivor services: a cluster-controlled trial in Nairobi, Kenya

This study was undertaken to evaluate the effect of a reproductive empowerment contraceptive counselling intervention (ARCHES) adapted to private clinics in Nairobi, Kenya on proximal outcomes of contraceptive use and covert use, self-efficacy, awareness and use of intimate partner violence (IPV) survivor services, and attitudes justifying reproductive coercion (RC) and IPV. We conducted a cluster-controlled trial among female family planning patients (N = 659) in six private clinics non-randomly assigned to ARCHES or control in and around Nairobi, Kenya. Patients completed interviews immediately before (baseline) and after (exit) treatment and at three- and six-month follow-up. We use inverse probability by treatment weighting (IPTW) applied to difference-in-differences marginal structural models to estimate the treatment effect using a modified intent-to-treat approach. After IPTW, women receiving ARCHES contraceptive counselling, relative to controls, were more likely to receive a contraceptive method at exit (86% vs. 75%, p < 0.001) and had a significantly greater relative increase in awareness of IPV services at from baseline to three- (beta 0.84, 95% CI 0.13, 1.55) and six-month follow-up (beta 0.92, 95% CI 0, 1.84) and a relative decrease in attitudes justifying RC from baseline to six-month follow-up (beta -0.34, 95% CI -0.65, -0.04). In the first evaluation of a clinic-based approach to address both RC and IPV in a low- or middle-income country (LMIC) context, we found evidence that ARCHES contraceptive counselling improved proximal outcomes related to contraceptive use and coping with RC and IPV. We recommend further study and refinement of this approach in Kenya and other LMICs.Plain Language Summary Reproductive coercion (RC) and intimate partner violence (IPV) are two forms of gender-based violence that are known to harm women's reproductive health. While one intervention, ARCHES - Addressing Reproductive Coercion in Health Settings, has shown promise to improve contraceptive use and help women cope with RC and IPV in the United States, no approach has been proven effective in a low- or middle-income country (LMIC) context. In the first evaluation of a reproductive empowerment contraceptive counselling intervention in an LMIC setting, we found that ARCHES contraceptive counselling, relative to standard contraceptive counselling, improved proximal outcomes on contraceptive uptake, covert contraceptive use, awareness of local violence survives, and reduced attitudes justifying RC among women seeking contraceptive services in Nairobi, Kenya. Distal outcomes will be reported separately. Findings from this study support the promise of addressing RC and IPV within routine contraceptive counselling in Kenya on women's proximal outcomes related to contraceptive use and coping with violence and coercion and should be used to inform the further study of this approach in Kenya and other LMICs.

Kidney function estimators for drug dose adjustment of direct oral anticoagulants in older adults with atrial fibrillation

Background

The Cockcroft-Gault equation (CrClC-G) is recommended for dose adjustment of direct oral anticoagulant drugs (DOACs) to kidney function. We aimed to assess whether defining DOAC dose appropriateness according to various kidney function estimators changed the associations between dose appropriateness and adverse events in older adults with atrial fibrillation (AF).

Methods

Participants of the Berlin Initiative Study with AF and treated with DOACs were included. We investigated CrClC-G and estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration and European Kidney Function Consortium equations based on creatinine and/or cystatin C. Marginal structural Cox models yielded confounder-adjusted hazard ratios for the risk of mortality, thromboembolism and bleeding associated with dose status.

Results

A total of 224 patients were included in the analysis (median age 87 years). Using CrClC-G, 154 (69%) had an appropriate dose of DOACs, 52 (23%) were underdosed and 18 (8%) were overdosed. During a 39-month median follow-up period, 109 (14.9/100 person-years) participants died, 25 (3.6/100 person-years) experienced thromboembolism and 60 (9.8/100 person-years) experienced bleeding. Dose status was not associated with mortality and thromboembolism, independent of the equation. Underdose status was associated with a lower risk of bleeding with all the equations compared with the appropriate dose group. In participants with discrepancies in dose status using CrClC-G and eGFR equations, the occurrence of endpoints did not differ between participants having an appropriate dose using CrClC-G or eGFR.

Conclusion

In older adults with AF, the association of DOAC dose status with adverse events did not differ when using CrClC-G or eGFR. Our results suggest that eGFR equations are not inferior to CrClC-G within this context.

Target Trial Emulation to Improve Causal Inference from Observational Data: What, Why, and How?

ABSTRACT

Target trial emulation has drastically improved the quality of observational studies investigating the effects of interventions. Its ability to prevent avoidable biases that have plagued many observational analyses has contributed to its recent popularity. This review explains what target trial emulation is, why it should be the standard approach for causal observational studies that investigate interventions, and how to do a target trial emulation analysis. We discuss the merits of target trial emulation compared with often used, but biased analyses, as well as potential caveats, and provide clinicians and researchers with the tools to better interpret results from observational studies investigating the effects of interventions.

Strategies to Address Current Challenges in Real-World Evidence Generation in Japan

The generation of real-world evidence (RWE), which describes patient characteristics or treatment patterns using real-world data (RWD), is rapidly growing more popular as a tool for decision-making in Japan. The aim of this review was to summarize challenges to RWE generation in Japan related to pharmacoepidemiology, and to propose strategies to address some of these challenges. We first focused on data-related issues, including the lack of transparency of RWD sources, linkage across different care settings, definitions of clinical outcomes, and the overall assessment framework of RWD when used for research purposes. Next the study reviewed methodology-related challenges. As lack of design transparency impairs study reproducibility, transparent reporting of study design is critical for stakeholders. For this review, we considered different sources of biases and time-varying confounding, along with potential study design and methodological solutions. Additionally, the implementation of robust assessment of definition uncertainty, misclassification, and unmeasured confounders would enhance RWE credibility in light of RWD source-related limitations, and is being strongly considered by task forces in Japan. Overall, the development of guidance for best practices on data source selection, design transparency, and analytical methods to address different sources of biases and robustness in the process of RWE generation will enhance credibility for stakeholders and local decision-makers.

Effect of anesthesia administration method on apgar scores of infants born to women undergoing elective cesarean section

BACKGROUND

Neonatal health at delivery as measured by apgar scores is an important outcome. This study was done to assess the impact of anesthesia on Apgar 1-minute and 5-minute scores of infants delivered through elective cesarean section in Zimbabwe.

METHODS

We carried out a secondary analysis of data from the Efficacy of Tranexamic Acid in Preventing Postpartum Hemorrhage (ETAPPH) clinical trial in Zimbabwe. Outcomes measured were infant Apgar scores at 1 and 5 min, exposure was the administration of either a general (intravenous propofol/ketamine/sodium thiopental) or spinal (hyperbaric bupivacaine 0.5%) anesthesia for anesthesia during the elective cesarean section procedure. Marginal Structural Logistic Modelling (MSM) using an unstabilized Inverse Probability Treatment Weight (IPTW) estimator was used to assess the relationship between anesthetic administration method and infant Apgar scores.

RESULTS

Four hundred and twenty-one (421) women who had an elective caesarean section in the ETAPPH study had their infants assessed for Apgar scores. Comparing general anesthesia to spinal anesthesia, spinal anesthesia was related to good Apgar scores at 1-minute (adjusted odds ratio [aOR] = 4.0, 95% Confidence Interval = 1.5-10.7, sensitivity analysis E-value = 3.41). Spinal anesthetic administration was also related to good Apgar scores at 5 min (adjusted odds ratio [aOR] = 6.2, 95% Confidence Interval = 1.6-23.1, sensitivity analysis E-value = 4.42).

CONCLUSIONS

When providing anesthesia for patients undergoing elective cesarean section, care should be taken on the method of administration of anesthetic agents. General anesthesia tends to depress Apgar scores at 1 min, although most neonates recover and have better scores at 5 min. Spinal anesthesia should be the first choice whenever possible.

TRIAL REGISTRATION

The clinical trial from which data of this study was abstracted was registered under clinical trials registration number NCT04733157.

Antimicrobial exposure is associated with decreased survival in triple-negative breast cancer

Antimicrobial exposure during curative-intent treatment of triple-negative breast cancer (TNBC) may lead to gut microbiome dysbiosis, decreased circulating and tumor-infiltrating lymphocytes, and inferior outcomes. Here, we investigate the association of antimicrobial exposure and peripheral lymphocyte count during TNBC treatment with survival, using integrated electronic medical record and California Cancer Registry data in the Oncoshare database. Of 772 women with stage I-III TNBC treated with and without standard cytotoxic chemotherapy - prior to the immune checkpoint inhibitor era - most (654, 85%) used antimicrobials. Applying multivariate analyses, we show that each additional total or unique monthly antimicrobial prescription is associated with inferior overall and breast cancer-specific survival. This antimicrobial-mortality association is independent of changes in neutrophil count, is unrelated to disease severity, and is sustained through year three following diagnosis, suggesting antimicrobial exposure negatively impacts TNBC survival. These results may inform mechanistic studies and antimicrobial prescribing decisions in TNBC and other hormone receptor-independent cancers.

Dynamics of Plasma Refill Rate and Intradialytic Hypotension During Hemodialysis: Retrospective Cohort Study With Causal Methodology

Key Points

Directly studying plasma refill rate (PRR) during hemodialysis (HD) can offer insight into physiologic mechanisms that change throughout HD. PRR at the start and during HD is associated with intradialytic hypotension, independent of ultrafiltration rate. A rising PRR during HD may be an early indicator of compensatory mechanisms for impending circulatory instability.

Background

Attaining the optimal balance between achieving adequate volume removal while preserving organ perfusion is a challenge for patients receiving maintenance hemodialysis (HD). Current strategies to guide ultrafiltration are inadequate.

Methods

We developed an approach to calculate the plasma refill rate (PRR) throughout HD using hematocrit and ultrafiltration data in a retrospective cohort of patients receiving maintenance HD at 17 dialysis units from January 2017 to October 2019. We studied whether (1 ) PRR is associated with traditional risk factors for hemodynamic instability using logistic regression, (2 ) low starting PRR is associated with intradialytic hypotension (IDH) using Cox proportional hazard regression, and (3 ) time-varying PRR throughout HD is associated with hypotension using marginal structural modeling.

Results

During 180,319 HD sessions among 2554 patients, PRR had high within-patient and between-patient variability. Female sex and hypoalbuminemia were associated with low PRR at multiple time points during the first hour of HD. Low starting PRR has a higher hazard of IDH, whereas high starting PRR was protective (hazard ratio [HR], 1.26, 95% confidence interval [CI], 1.18 to 1.35 versus HR, 0.79, 95% CI, 0.73 to 0.85, respectively). However, when accounting for time-varying PRR and time-varying confounders, compared with a moderate PRR, while a consistently low PRR was associated with increased risk of hypotension (odds ratio [OR], 1.09, 95% CI, 1.02 to 1.16), a consistently high PRR had a stronger association with hypotension within the next 15 minutes (OR, 1.38, 95% CI, 1.30 to 1.45).

Conclusions

We present a straightforward technique to quantify plasma refill that could easily integrate with devices that monitor hematocrit during HD. Our study highlights how examining patterns of plasma refill may enhance our understanding of circulatory changes during HD, an important step to understand how current technology might be used to improve hemodynamic instability.

Variability of the response to immunotherapy among subgroups of patients with multiple sclerosis

BACKGROUND AND PURPOSE

This study assessed the effect of patient characteristics on the response to disease-modifying therapy (DMT) in multiple sclerosis (MS).

METHODS

We extracted data from 61,810 patients from 135 centers across 35 countries from the MSBase registry. The selection criteria were: clinically isolated syndrome or definite MS, follow-up ≥ 1 year, and Expanded Disability Status Scale (EDSS) score ≥ 3, with ≥1 score recorded per year. Marginal structural models with interaction terms were used to compare the hazards of 12-month confirmed worsening and improvement of disability, and the incidence of relapses between treated and untreated patients stratified by their characteristics.

RESULTS

Among 24,344 patients with relapsing MS, those on DMTs experienced 48% reduction in relapse incidence (hazard ratio [HR] = 0.52, 95% confidence interval [CI] = 0.45-0.60), 46% lower risk of disability worsening (HR = 0.54, 95% CI = 0.41-0.71), and 32% greater chance of disability improvement (HR = 1.32, 95% CI = 1.09-1.59). The effect of DMTs on EDSS worsening and improvement and the risk of relapses was attenuated with more severe disability. The magnitude of the effect of DMT on suppressing relapses declined with higher prior relapse rate and prior cerebral magnetic resonance imaging activity. We did not find any evidence for the effect of age on the effectiveness of DMT. After inclusion of 1985 participants with progressive MS, the effect of DMT on disability mostly depended on MS phenotype, whereas its effect on relapses was driven mainly by prior relapse activity.

CONCLUSIONS

DMT is generally most effective among patients with lower disability and in relapsing MS phenotypes. There is no evidence of attenuation of the effect of DMT with age.

Hypothetical intervention of targeted systolic blood pressure control of < 120 mmHg on renal prognosis for persons with stage 3-4 chronic kidney disease: an application of parametric g-formula using health checkup data in Japan

BACKGROUND

The revised KDIGO guidelines recommend maintaining systolic blood pressure (sBP) < 120 mmHg in patients with chronic kidney disease (CKD), based on cardiovascular and survival benefits. However, the renal benefit of this strategy remains less clear.

METHODS

We used data of routine health checkups in Japan. Persons whose estimated glomerular filtration rate (eGFR) was < 60 mL/min/1.73 m² in 2015 without end-stage disease were followed until 2020. We estimated the 5-year benefit of hypothetical targeted sBP control using parametric g-formula modeling, accounting for both time-fixed and time-varying confounding variables. Four sensitivity analyses, including analysis using a marginal structural model (MSM) and positive control outcome analysis, were also done.

RESULTS

We enrolled 28,972 persons with CKD (median age: 54 years, male: 69%, baseline eGFR [median]: 56 mL/min/1.73m²). As compared with the natural course without a targeted intervention, there was no renoprotective effect of targeted sBP control, with a 5-year difference in eGFR of 0.65 mL/min/1.73 m² (95% confidence interval - 0.42 to 1.65 mL/min/1.73 m²). MSM analysis found a similar result. In contrast, the positive control analysis using the cardiovascular outcome showed that targeted sBP control would reduce the cardiovascular disease incidence by 6.0% over 5 years.

CONCLUSIONS

A targeted sBP control strategy maintaining < 120 mmHg may not yield a renoprotective effect for patients with stage 3-4 CKD, although it was expected to offer a cardiovascular benefit. Future research may be warranted in higher-risk populations, such as elderly people or those with more advanced kidney disease.

Sodium-Glucose Cotransporter-2 Inhibitors for Hyperglycemia in Phosphoinositide 3-kinase Pathway Inhibition

Purpose Phosphoinositide 3-kinase (PI3K) inhibition is used for the treatment of certain cancers, but can cause profound hyperglycemia and insulin resistance, for which sodium-glucose cotransporter-2 (SGLT2) inhibitors have been proposed as a preferred therapy. The objective of this research is to assess the effectiveness and safety of SGLT2 inhibitors for hyperglycemia in PI3K inhibition. Methods We conducted a single-center retrospective review of adults initiating the PI3k inhibitor alpelisib. Exposure to different antidiabetic drugs and adverse events including diabetic ketoacidosis (DKA) were assessed through chart review. Plasma and point-of-care blood glucoses were extracted from the electronic medical record. Change in serum glucose and the rate of DKA on SGLT2 inhibitor versus other antidiabetic drugs were examined as co-primary outcomes. Results We identified 103 patients meeting eligibility criteria with median follow-up of 85 days after starting alpelisib. When SGLT2 inhibitors were used to treat hyperglycemia, they were associated with a decrease in mean random glucose by -54 mg/dL (95% CI -99 to -8) in adjusted linear modeling. Five cases of DKA were identified, two occurring in patients on alpelisib plus SGLT2 inhibitor. Estimated incidence of DKA was: alpelisib plus SGLT2 inhibitor, 24 DKA cases per 100 patient-years (95% CI 6, 80); alpelisib with non-SGLT2 inhibitor antidiabetic drugs, 7 (95% CI 0.1, 34); alpelisib only, 4 (95% CI 0.1, 21). Conclusions SGLT2 inhibitors are effective treatments for hyperglycemia in the setting of PI3K inhibition, but given possible adverse events, SGLT2 inhibitors should be used with caution.

A healthful plant-based eating pattern is longitudinally associated with higher insulin sensitivity in Australian adults

BACKGROUND

A healthful plant-based eating pattern is associated with lower type 2 diabetes risk; however, the association with its preceding state, compromised insulin sensitivity, is less well-established, particularly in younger populations with repeated measures of diet over time.

OBJECTIVE

We aimed to examine the longitudinal relationship between a healthful plant-based eating pattern and insulin sensitivity in young to middle-aged adults.

METHODS

We included 667 participants from the Childhood Determinants of Adult Health (CDAH) study, a population-based cohort in Australia. Healthful plant-based diet index (hPDI) scores were derived from food frequency questionnaire data. Plant foods considered 'healthful' were scored positively (e.g., whole grains, fruit, vegetables), with all remaining foods scored reversely (e.g., refined grains, soft drinks, meat). Updated homeostatic model assessment (HOMA2) estimated insulin sensitivity from fasting insulin and glucose concentrations. We used linear mixed-effects regression to analyse data from two time points: CDAH-1 (2004-06, aged 26-36 years) and CDAH-3 (2017-19, aged 36-49 years). hPDI scores were modelled as between- and within-person effects (i.e., a participant's overall mean and their deviation from said mean at each time point, respectively).

RESULTS

The median follow-up duration was 13 years. In our primary analysis, each 10-unit difference in hPDI score was associated with higher log-HOMA2 insulin sensitivity [95% confidence interval], with between-person (β = 0.11 [0.05, 0.17], P < .001) and within-person effects (β = 0.10 [0.04, 0.16], P = .001). The within-person effect persisted despite accounting for compliance with dietary guidelines. Adjustment for waist circumference attenuated the between-person effect by 70% (P = .26) and the within-person effect by 40% (P = .04).

CONCLUSIONS

In young to middle-aged Australian adults, a healthful plant-based eating pattern (determined using hPDI scores) was longitudinally associated with higher insulin sensitivity, and therefore, potentially lower type 2 diabetes risk later in life.

Risk of Underlying Diseases and Effectiveness of Drugs on COVID-19 Inpatients Assessed Using Medical Claims in Japan: Retrospective Observational Study

Background

Results of earlier studies have demonstrated underlying diseases such as cancer, diabetes mellitus, immunodeficiency, hypertension and heart failure to be risk factors for severe outcomes and mortality. Furthermore, clinical trials have shown that drugs such as antiviral drugs, antibody cocktails, steroids and anti-inflammatory drugs can be expected to prevent severe COVID-19 outcomes and death.

Methods

This study, using inpatient records from the Medical Information Analysis Databank covering national hospital organizations in Japan, was conducted to evaluate the effects of underlying diseases and/or administered drugs on mortality. Subjects were all inpatients receiving oxygen administration and inpatients using respiratory ventilators, categorized by three age classes: all ages, patients 65 years old or older, and patients younger than 65 years old. We used logistic regression to analyze outcomes for underlying diseases, administered drugs, age, sex, the proportion of the mutated strains, and vaccine coverage.

Results

Patients with hypertension, except for younger inpatients, have a lower risk of mortality (estimated coefficient 0.67 among all inpatients (p < 0.01): 0.77 among inpatients with oxygen therapy (p = 0.02) and 0.57 among inpatients with respiratory ventilation w (p = 0.01)). Except for younger inpatients, antibody cocktail (casirivimab/imdevimab or sotrovimab) administration was associated with a higher probability of survival (estimated coefficient 0.27 among all inpatients (p < 0.01)). It raised the survival probability consistently, although other drugs might have reduced the probability of survival.

Conclusion

These findings suggest that antiviral drugs (remdesivir, estimated coefficient 1.44 (p < 0.01)), steroids (dexamethasone, estimated coefficient 1.85 (p < 0.01)), and anti-inflammatory drugs (baricitinib, estimated coefficient 1.62 (p < 0.01), and tocilizumab, estimated coefficient 2.73 (p < 0.01)) might not contribute to survival. These results have not been reported from earlier studies. More sophisticated estimation procedures, such as treatment effect models, are necessary to obtain conclusive results.

Moderate Alcohol Consumption and Depression: A Marginal Structural Model Approach Promoting Causal Inference

OBJECTIVE

Moderate alcohol consumption is associated with decreased risk for depression, but it remains unclear whether this is a causal relationship or a methodological artifact. To compare the effects of consistent abstinence and occasional, moderate, and above-guideline alcohol consumption throughout early to middle adulthood on depression at age 50, the authors conducted a secondary analysis of the National Longitudinal Survey of Youth 1979 cohort and employed a marginal structural model (MSM) approach.

METHODS

Baseline was set at 1994, when individuals were ages 29-37. The MSM incorporated measurements of alcohol consumption in 1994, 2002, and 2006, baseline and time-varying covariates, and repeated measurements with the Center for Epidemiologic Studies Depression Scale-Short Form (CES-D-SF). A total of 5,667 eligible participants provided valid data at baseline, 3,593 of whom provided valid outcome data. The authors used all observed data to predict CES-D-SF means and rates of probable depression for hypothetical trajectories of consistent alcohol consumption.

RESULTS

The results approximated J-curve relationships. Specifically, both consistent occasional and consistent moderate drinkers were predicted to have reduced CES-D-SF scores and rates of probable depression at age 50 compared with consistent abstainers (CES-D-SF scores: b=-0.84, 95% CI=-1.47, -0.11; probable depression: odds ratio=0.58, 95% CI=0.36, 0.88 for consistent occasional drinkers vs. abstainers; CES-D-SF scores: b=-1.08, 95% CI=-1.88, -0.20; probable depression: odds ratio=0.59, 95% CI=0.26, 1.13 for consistent moderate drinkers vs. consistent abstainers). Consistent above-guideline drinkers were predicted to have slightly increased risk compared with consistent abstainers, but this was not significant. In sex-stratified analyses, results were similar for females and males.

CONCLUSIONS

This study contributes preliminary evidence that associations between moderate alcohol consumption and reduced risk for depression may reflect genuine causal effects. Further research using diverse methodologies that promote causal inference is required.

Fatty liver mediates the association of hyperuricemia with prediabetes and diabetes: a weighting-based mediation analysis

Background

Fatty liver, obesity, and dyslipidemia are associated with prediabetes or diabetes risk, and hyperuricemia co-exists. The present study evaluated the role of multiple mediators, namely, fatty liver, body mass index (BMI), and dyslipidemia, in the association between hyperuricemia and diabetes status.

Methods

Baseline data from the ongoing Fuqing cohort (5,336 participants) were analyzed to investigate the association of hyperuricemia with diabetes status using a multinomial logistic regression model. Furthermore, causal mediation analysis with the weighting-based approach was performed to estimate hyperuricemia's total natural direct effect (tnde), total natural indirect effect (tnie), and total effect (te) on prediabetes and diabetes risk, mediating jointly via fatty liver, BMI, and dyslipidemia.

Results

In multinomial analysis without considering mediators' effects, hyperuricemia was associated with a higher risk of prediabetes only (odds ratio: 1.25; 95% CI: 1.09-1.43; p < 0.001). When fatty liver, BMI, and dyslipidemia were considered as multiple mediators in the association, hyperuricemia was linked to both prediabetes [tnde: 1.11, 95% CI: 1.04-1.11; tnie: 1.07, 95% CI: 1.05-1.09; and overall proportion mediated (pm): 42%, 95% CI: 27%-73%] and diabetes risk (tnde: 0.96, 95% CI: 0.82-1.14; tnie: 1.25, 95% CI: 1.18-1.33; and pm: 100%, 95% CI: 57%-361%). Hyperuricemia showed significant tnde, te, and tnie, mediated by fatty liver jointly with dyslipidemia (pm = 17%) or BMI (pm = 35%), on prediabetes risk.

Conclusion

Hyperuricemia could increase prediabetes or diabetes risk, partially mediated by fatty liver, BMI, and dyslipidemia. Fatty liver is the crucial mediator in the association between hyperuricemia and prediabetes.

Association of fluoroquinolones or cephalosporin plus macrolide with Clostridioides difficile infection (CDI) after treatment for community-acquired pneumonia

OBJECTIVE

Clostridioides difficile infection (CDI) is the most common cause of gastroenteritis, and community-acquired pneumonia (CAP) is the most common infection treated in hospitals. American Thoracic Society (ATS)/Infectious Diseases Society of America (IDSA) CAP guidelines recommend empiric therapy with a respiratory fluoroquinolone or cephalosporin plus macrolide combination, but the CDI risk of these regimens is unknown. We examined the association between each antibiotic regimen and the development of hospital-onset CDI.

METHODS

We conducted a retrospective cohort study using data from 638 US hospitals contributing administrative including 177 also contributing microbiologic data to Premier, Inc. We included adults admitted with pneumonia and discharged from July 2010 through June 2015 with a pneumonia diagnosis code who received ≥3 days of either empiric regimen. Hospital-onset CDI was defined by a diagnosis code not present on admission and positive laboratory test on day 4 or later or readmission for CDI. Mixed propensity-weighted multiple logistic regression was used to estimate the associations of CDI with antibiotic regimens.

RESULTS

Our sample included 58,060 patients treated with either cephalosporin plus macrolide (36,796 patients) or a fluoroquinolone alone (21,264 patients) and with microbiological data; 127 (0.35%) patients who received cephalosporin plus macrolide and 65 (0.31%) who received a fluoroquinolone developed CDI. After adjustment for patient demographics, comorbidities, risk factors for antimicrobial resistance, and hospital characteristics, CDI risks were similar for fluoroquinolones versus cephalosporin plus macrolide (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.70-1.38).

CONCLUSION

Among patients with CAP at US hospitals, CDI was uncommon, occurring in ∼0.33% of patients. We did not detect a significant association between the choice of empiric guideline recommended antibiotic therapy and the development of CDI.

These Are Not the Effects You Are Looking for: Causality and the Within-/Between-Persons Distinction in Longitudinal Data Analysis

In psychological science, researchers often pay particular attention to the distinction between within- and between-persons relationships in longitudinal data analysis. Here, we aim to clarify the relationship between the within- and between-persons distinction and causal inference and show that the distinction is informative but does not play a decisive role in causal inference. Our main points are threefold. First, within-persons data are not necessary for causal inference; for example, between-persons experiments can inform about (average) causal effects. Second, within-persons data are not sufficient for causal inference; for example, time-varying confounders can lead to spurious within-persons associations. Finally, despite not being sufficient, within-persons data can be tremendously helpful for causal inference. We provide pointers to help readers navigate the more technical literature on longitudinal models and conclude with a call for more conceptual clarity: Instead of letting statistical models dictate which substantive questions researchers ask, researchers should start with well-defined theoretical estimands, which in turn determine both study design and data analysis.

The effect of time-varying capacity utilization on 14-day in-hospital mortality: a retrospective longitudinal study in Swiss general hospitals

BACKGROUND

High bed-occupancy (capacity utilization) rates are commonly thought to increase in-hospital mortality; however, little evidence supports a causal relationship between the two. This observational study aimed to assess three time-varying covariates-capacity utilization, patient turnover and clinical complexity level- and to estimate causal effect of time-varying high capacity utilization on 14 day in-hospital mortality.

METHODS

This retrospective population-based analysis was based on routine administrative data (n = 1,152,506 inpatient cases) of 102 Swiss general hospitals. Considering the longitudinal nature of the problem from available literature and expert knowledge, we represented the underlying data generating mechanism as a directed acyclic graph. To adjust for patient turnover and patient clinical complexity levels as time-varying confounders, we fitted a marginal structure model (MSM) that used inverse probability of treatment weights (IPTWs) for high and low capacity utilization. We also adjusted for patient age and sex, weekdays-vs-weekend, comorbidity weight, and hospital type.

RESULTS

For each participating hospital, our analyses evaluated the ≥85th percentile as a threshold for high capacity utilization for the higher risk of mortality. The mean bed-occupancy threshold was 83.1% (SD 8.6) across hospitals and ranged from 42.1 to 95.9% between hospitals. For each additional day of exposure to high capacity utilization, our MSM incorporating IPTWs showed a 2% increase in the odds of 14-day in-hospital mortality (OR 1.02, 95% CI: 1.01 to 1.03).

CONCLUSIONS

Exposure to high capacity utilization increases the mortality risk of inpatients. Accurate monitoring of capacity utilization and flexible human resource planning are key strategies for hospitals to lower the exposure to high capacity utilization.

Use of low-dose quetiapine increases the risk of major adverse cardiovascular events: results from a nationwide active comparator-controlled cohort study

At standard doses used for schizophrenia or bipolar disorder, quetiapine has been associated with weight gain and increased levels of triglycerides, to-tal cholesterol and low-density lipoprotein (LDL) cholesterol, which are risk factors for cardiovascular morbidity and mortality. However, this drug is also commonly used off-label at low doses for anxiolytic or hypnotic purposes, and its cardiovascular safety at these doses is unknown. We aimed to assess the risk of major adverse cardiovascular events with use of low-dose quetiapine compared to use of Z-drug hypnotics in a nationwide, active comparator-controlled cohort study. The cohort included new users of either drugs in Denmark from 2003 to 2017, aged 18-85 years, without history of ischemic stroke, myocardial infarction, cancer, and severe mental illness. The main outcome was the occurrence of major adverse cardiovascular events, defined as non-fatal myocardial infarction or ischemic stroke, or death from cardiovascular causes. Selective serotonin reuptake inhibitors (SSRIs) were used as an alternative comparator in sensitivity analyses. Altogether, we compared 60,566 low-dose quetiapine users with 454,567 Z-drug users, followed for 890,198 person-years in intent-to-treat analysis, and 330,334 person-years in as-treated analysis. In intention-to-treat analysis, low-dose quetiapine was associated with an increased risk of major adverse cardiovascular events (adjusted hazard ratio, aHR=1.13, 95% CI: 1.02-1.24, p=0.014) and cardiovascular death (aHR=1.26, 95% CI: 1.11-1.43, p<0.001). In as-treated analysis, continuous low-dose quetiapine use was associated with increased risk of major adverse cardiovascular events (aHR=1.52, 95% CI: 1.35-1.70, p<0.001), non-fatal ischemic stroke (aHR=1.37, 95% CI: 1.13-1.68, p=0.002) and cardiovascular death (aHR=1.90, 95% CI: 1.64-2.19, p<0.001). The risk of major adverse cardiovascular events was greater in women (aHR=1.28, p=0.02) and those aged ≥65 years at initiation (aHR=1.24, p<0.001). Compared to SSRIs, low-dose quetiapine use was associated with an increased risk of major adverse cardiovascular events (aHR=1.42, p<0.001), non-fatal ischemic stroke (aHR=1.27, p=0.0028) and cardiovascular death (aHR=1.72, p<0.001). So, we conclude that the use of low-dose quetiapine is associated with an increased risk of major adverse cardiovascular events, especially in women and the elderly. On the basis of these findings, we suggest that use of off-label low-dose quetiapine for sedative or hypnotic purposes should be discouraged.

Superior effects of natalizumab versus other DMTs on patient-reported outcomes in people with multiple sclerosis

BACKGROUND

Little is known about the comparative effectiveness of multiple sclerosis (MS) disease-modifying therapies (DMTs) on patient-reported outcomes in MS. We compared the effects of natalizumab to other DMTs in relation to MS symptom severity, quality of life, disability, disease progression and employment outcomes using real-world data.

METHODS

We included 2817 observations in 2015, 2016 and 2017 from 1382 participants in the Australian MS Longitudinal Study. Information on treatment, health and employment outcomes was prospectively collected by questionnaires. Marginal structural models with interaction terms for DMT×time were used to compare natalizumab and other comparator treatment groups.

RESULTS

Natalizumab was associated with improvements over time, or general trends of improvement, in the severity of many symptoms and work productivity loss. Compared with any other DMTs, natalizumab was associated with superior effects over time for 8 of 23 patient-reported outcomes, with similar directions of effect observed for another 6, demonstrating consistency. There were no differences in effect for spasticity, fatigue, pain, feelings of depression, disability, European quality of life five dimension index, presenteeism and work status. Natalizumab did not perform significantly worse over time compared with any other DMTs for any of the outcomes.

CONCLUSIONS

Natalizumab was associated with superior outcomes over time for many patient-reported health and employment outcomes when compared with other DMTs in this large prospective cohort study. These findings may influence treatment selection in clinical practice and future treatment cost-effectiveness analyses.

Strategies to manage auxiliary pain medications in chronic pain trials: a topical review

Chronic pain trials commonly allow auxiliary pain medications such as rescue and concomitant analgesics in addition to the randomized treatment. Changes in auxiliary pain medications after randomization represent intercurrent events that may affect either the interpretation or the existence of the measurements associated with the clinical question of interest, complicating the assessment of treatment efficacy. In chronic pain trials, pain intensity typically varies and patients may take the auxiliary medications 1 day but not the next or increase and decrease the dosages temporarily while continuing their randomized study medication. This distinctive feature of auxiliary pain medications as an intercurrent event has received little attention in the literature. Further clarifications on how to manage these issues are therefore pressing. Here we provide perspectives on issues related to auxiliary pain medication-related intercurrent events in randomized controlled chronic pain trials considering the strategies suggested in the E9(R1) addendum to the ICH guideline on statistical principles for clinical trials.

Mortality Among Patients Undergoing Blood Transfusion in Relation to Donor Sex and Parity: A Natural Experiment

Importance

Prior evidence suggests that plasma and platelet transfusions from female and parous donors are associated with adverse clinical outcomes, which has led to the predominant use of male donors for plasma and platelets in many countries. However, studies on red blood cell transfusions have been conflicting.

Objective

To determine whether blood donor sex and parity affect mortality of patients undergoing transfusion with red blood cells.

Design, Setting, and Participants

This cohort study used nationwide blood bank and health register data in Sweden and involved a natural experiment created by donor sex and parity being concealed and randomly allocated. Patients were included if they were 18 to 90 years old, did not have a history of blood transfusion, and received a transfusion between January 1, 2010, and December 31, 2017. Patients were followed up from their first red blood cell transfusion until death, emigration, or end of study (June 30, 2018). Data analysis was performed between June 15 and December 15, 2021.

Exposures

(1) Female vs male donors and (2) parous or nonparous female vs male donors.

Main Outcomes and Measures

Overall survival up to 2 years estimated using inverse probability-weighted Kaplan-Meier estimates and relative risk for additional transfusions within 24 hours.

Results

Among the 368 778 included patients (mean [SD] age, 66.3 [17.7] years; 57.3% female), 2-year survival differences comparing red blood cell transfusions from female and parous donors to male donors were -0.1% (95% CI, -1.3% to 1.1%) and 0.3% (95% CI, -0.6% to 1.2%), respectively. No statistically significant survival differences were observed regardless of patient sex or age. Median (IQR) hemoglobin counts for female donors (13.5 [13.0-14.0] g/dL) were lower than for male donors (14.9 [14.4-15.5] g/dL). Red blood cell transfusions from female donors were associated with a relative risk of 1.12 (95% CI, 1.08-1.17) for additional transfusions within 24 hours but not after adjusting for donor hemoglobin counts (relative risk, 1.03; 95% CI, 0.98-1.08). Pretransfusion patient characteristics were naturally distributed as-if randomized.

Conclusions and Relevance

In this nationwide cohort study involving a natural experiment, after accounting for the lower hemoglobin values in blood from female donors, patients undergoing transfusion with blood from female or parous donors did not have higher 2-year mortality compared with recipients of blood from male donors.

Long-term weight changes and risk of rheumatoid arthritis among women in a prospective cohort: a marginal structural model approach

OBJECTIVE

To examine the association of long-term weight change with RA risk in a large prospective cohort study.

METHODS

The Nurses' Health Study II started in 1989 (baseline); after exclusions, we studied 108 505 women 25-42 years old without RA. Incident RA was reported by participants and confirmed by medical record review. Body weight was reported biennially through 2015. We investigated two time-varying exposures: weight changes from baseline and from age 18; change was divided into five categories. We used a marginal structural model approach to account for time-varying weight change and covariates.

RESULTS

Over 2 583 266 person-years, with a median follow-up time of 25.3 years, 541 women developed RA. Compared with women with stable weight from baseline, weight change was significantly associated with increased RA risk [weight gain 2-<10 kg: RR = 1.98 (95% CI 1.38, 2.85); 10-<20 kg: RR = 3.28 (95% CI 2.20, 4.89); ≥20 kg: RR = 3.81 (95% CI 2.39, 6.07); and weight loss >2 kg: RR = 2.05 (95% CI 1.28, 3.28)]. Weight gain of 10 kg or more from age 18 compared with stable weight was also associated with increased RA risk [10-< 20 kg: RR = 2.12 (95% CI 1.37, 3.27), ≥20 kg: RR = 2.31 (95% CI 1.50, 3.56)]. Consistent findings were observed for seropositive and seronegative RA.

CONCLUSION

Long-term weight gain was strongly associated with increased RA risk in women, with weight gain of ≥20 kg associated with more than a three-fold increased RA risk. Maintenance of healthy weight may be a strategy to prevent or delay RA.

Comparative Effectiveness of Dialysis Modality on Laboratory Parameters of Mineral Metabolism

INTRODUCTION

Chronic kidney disease-mineral and bone disorders (CKD-MBD) are prevalent in patients undergoing maintenance dialysis. Yet, there are limited and mixed evidence on the effects of different dialysis modalities involving longer treatment times or higher frequencies on CKD-MBD markers.

METHODS

This cohort study used data from 132,523 incident dialysis patients treated with any of the following modalities: conventional thrice-weekly in-center hemodialysis, nocturnal in-center hemodialysis (NICHD), home hemodialysis (HHD), or peritoneal dialysis (PD) from 2007 to 2011. We used marginal structural models fitted with inverse probability weights to adjust for fixed and time-varying confounding and informative censoring. We estimated the average effects of treatments with different dialysis modalities on time-varying serum concentrations of CKD-MBD markers: albumin-corrected calcium, phosphate, parathyroid hormone (PTH), and alkaline phosphatase (ALP) using pooled linear regression.

RESULTS

Most of the cohort were exclusively treated with conventional in-center hemodialysis, while few were ever treated with NICHD or HHD. At the baseline, PD patients had the lowest mean and median values of PTH, while NICHD patients had the highest median values. During follow-up, compared to hemodialysis patients, patients treated with NICHD had lower mean serum PTH (19.8 pg/mL [95% confidence interval: 2.8, 36.8] lower), whereas PD and HHD patients had higher mean PTH (39.7 pg/mL [31.6, 47.8] and 51.2 pg/mL [33.0, 69.3] higher, respectively). Compared to hemodialysis patients, phosphate levels were lower for patients treated with NICHD (0.44 mg/dL [0.37, 0.52] lower), PD (0.15 mg/dL [0.12, 0.19] lower), or HHD (0.33 mg/dL [0.27, 0.40] lower). There were no clinically meaningful associations between dialysis modalities and concentrations of calcium or ALP.

CONCLUSION

In incident dialysis patients, compared to treatment with conventional in-center hemodialysis, treatments with other dialysis modalities with longer treatment times or higher frequency were associated with different patterns of serum phosphate and PTH. Given the recent growth in the use of dialysis modalities other than hemodialysis, the associations between the treatment and the CKD-MBD markers warrant additional study.

Are there non-linear relationships between alcohol consumption and long-term health?: a systematic review of observational studies employing approaches to improve causal inference

Background

Research has long found ‘J-shaped’ relationships between alcohol consumption and certain health outcomes, indicating a protective effect of moderate consumption. However, methodological limitations in most studies hinder causal inference. This review aimed to identify all observational studies employing improved approaches to mitigate confounding in characterizing alcohol–long-term health relationships, and to qualitatively synthesize their findings.

Methods

Eligible studies met the above description, were longitudinal (with pre-defined exceptions), discretized alcohol consumption, and were conducted with human populations. MEDLINE, PsycINFO, Embase and SCOPUS were searched in May 2020, yielding 16 published manuscripts reporting on cancer, diabetes, dementia, mental health, cardiovascular health, mortality, HIV seroconversion, and musculoskeletal health. Risk of bias of cohort studies was evaluated using the Newcastle-Ottawa Scale, and a recently developed tool was used for Mendelian Randomization studies.

Results

A variety of functional forms were found, including reverse J/J-shaped relationships for prostate cancer and related mortality, dementia risk, mental health, and certain lipids. However, most outcomes were only evaluated by a single study, and few studies provided information on the role of alcohol consumption pattern.

Conclusions

More research employing enhanced causal inference methods is urgently required to accurately characterize alcohol–long-term health relationships. Those studies that have been conducted find a variety of linear and non-linear functional forms, with results tending to be discrepant even within specific health outcomes.

Trial registration

PROSPERO registration number CRD42020185861.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01486-5.

Sunscreens With High Versus Low Sun Protection Factor and Cutaneous Squamous Cell Carcinoma Risk: A Population-Based Cohort Study

Evidence on sunscreen use and cutaneous squamous cell carcinoma (cSCC) risk is limited. Most studies have not taken sun protection factor (SPF) into consideration and used nonusers of sunscreen as the reference group. Nonusers are likely a priori at lower cSCC risk than users. No study has investigated the effect of high- versus low-SPF sunscreens on cSCC, appropriately adjusting for time-varying confounding. Using data from the Norwegian Women and Cancer Study (1991–2016), we investigated whether use of SPF ≥15 versus SPF <15 sunscreens reduces cSCC risk. We used a marginal structural Cox proportional hazards model with inverse probability of treatment and censoring weights to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During follow-up of 148,781 women (mean follow-up, 14.3 years), 653 women were diagnosed with cSCC. The effect on cSCC risk of sunscreens with SPF ≥15 versus SPF <15 was close to the null when used at any latitudes (HR = 1.02, 95% CI: 0.82, 1.27) and when used in lower-latitude settings (HR = 1.05, 95% CI: 0.84, 1.32). In conclusion, we found no indication that sunscreens with SPF ≥15 reduced Norwegian women’s cSCC risk more than sunscreens with SPF <15, suggesting that either there is no difference in their effects long-term or the difference is diluted by incorrect application.

Real-World Effectiveness and Immunogenicity of BNT162b2 and mRNA-1273 SARS-CoV-2 Vaccines in Patients on Hemodialysis

BACKGROUND

Patients on hemodialysis have an elevated risk for COVID-19 but were not included in efficacy trials of SARS-CoV-2 vaccines.

METHODS

We conducted a retrospective, observational study to estimate the real-world effectiveness and immunogenicity of two mRNA SARS-CoV-2 vaccines in a large, representative population of adult hemodialysis patients in the United States. In separate, parallel analyses, patients who began a vaccination series with BNT162b2 or mRNA-1273 in January and February 2021 were matched with unvaccinated patients and risk for outcomes were compared for days 1-21, 22-42, and ≥43 after first dose. In a subset of consented patients, blood samples were collected approximately 28 days after the second dose and anti-SARS-CoV-2 immunoglobulin G was measured.

RESULTS

A total of 12,169 patients received the BNT162b2 vaccine (matched with 44,377 unvaccinated controls); 23,037 patients received the mRNA-1273 vaccine (matched with 63,243 unvaccinated controls). Compared with controls, vaccinated patients' risk of being diagnosed with COVID-19 postvaccination became progressively lower during the study period (hazard ratio and 95% confidence interval for BNT162b2 was 0.21 [0.13, 0.35] and for mRNA-1273 was 0.27 [0.17, 0.42] for days ≥43). After a COVID-19 diagnosis, vaccinated patients were significantly less likely than unvaccinated patients to be hospitalized (for BNT162b2, 28.0% versus 43.4%; for mRNA-1273, 37.2% versus 45.6%) and significantly less likely to die (for BNT162b2, 4.0% versus 12.1%; for mRNA-1273, 5.6% versus 14.5%). Antibodies were detected in 98.1% (309/315) and 96.0% (308/321) of BNT162b2 and mRNA-1273 patients, respectively.

CONCLUSIONS

In patients on hemodialysis, vaccination with BNT162b2 or mRNA-1273 was associated with a lower risk of COVID-19 diagnosis and lower risk of hospitalization or death among those diagnosed with COVID-19. SARS-CoV-2 antibodies were detected in nearly all patients after vaccination. These findings support the use of these vaccines in this population.

Comparison of COVID-19 mitigation and decompression strategies among homeless shelters: a prospective cohort study

PURPOSE

To compare the effectiveness of COVID-19 mitigation strategies in two homeless shelters in Massachusetts during the pandemic.

METHODS

We conducted a prospective cohort study that followed guests in two Massachusetts homeless shelters between March 30 and May 13, 2020, which adopted different depopulation strategies. One set up temporary tents in its parking lot, while the other decompressed its guests to a gym and a hotel. The outcome was assessed by comparing the odds ratios of positive SARS-CoV-2 RT-PCR assays.

RESULTS

Guests residing at the shelter that used temporary tents had 6.21 times (95% CI = 1.86, 20.77) higher odds of testing positive for SARS-CoV-2 at follow-up after adjusting for loss to follow up, age, gender, and race. The daily COVID-19 symptoms checklist performed poorly in detecting positive infection.

CONCLUSIONS

The study highlights the importance of depopulating shelter guests with stable and adequate indoor space to prevent SARS-CoV-2 transmission. Daily temperature and symptom checks should be combined with routine testing. With the rising homelessness due to mass unemployment and eviction crisis, our study supports further governmental assistance in decompressing homeless shelters during this pandemic.

Adding a New Medication Versus Maximizing Dose to Intensify Hypertension Treatment in Older Adults : A Retrospective Observational Study

BACKGROUND

There are 2 approaches to intensifying antihypertensive treatment when target blood pressure is not reached, adding a new medication and maximizing dose. Which strategy is better is unknown.

OBJECTIVE

To assess the frequency of intensification by adding a new medication versus maximizing dose, as well as the association of each method with intensification sustainability and follow-up systolic blood pressure (SBP).

DESIGN

Large-scale, population-based, retrospective cohort study. Observational data were used to emulate a target trial with 2 groups, new medication and maximizing dose, who underwent intensification of their drug regimen.

SETTING

Veterans Health Administration (2011 to 2013).

PATIENTS

Veterans aged 65 years or older with hypertension, an SBP of 130 mm Hg or higher, and at least 1 antihypertensive medication at less than the maximum dose.

MEASUREMENTS

The following 2 intensification approaches were emulated: adding a new medication, defined as a total dose increase with new medication, and maximizing dose, defined as a total dose increase without new medication. Inverse probability weighting was used to assess the observational effectiveness of the intensification approach on sustainability of intensified treatment and follow-up SBP at 3 and 12 months.

RESULTS

Among 178 562 patients, 45 575 (25.5%) had intensification by adding a new medication and 132 987 (74.5%) by maximizing dose. Compared with maximizing dose, adding a new medication was associated with less intensification sustainability (average treatment effect, -15.2% [95% CI, -15.7% to -14.6%] at 3 months and -15.1% [CI, -15.6% to -14.5%] at 12 months) but a slightly larger reduction in mean SBP (-0.8 mm Hg [CI, -1.2 to -0.4 mm Hg] at 3 months and -1.1 mm Hg [CI, -1.6 to -0.6 mm Hg] at 12 months).

LIMITATION

Observational data; largely male population.

CONCLUSION

Adding a new antihypertensive medication was less frequent and was associated with less intensification sustainability but slightly larger reductions in SBP. Trials would provide the most definitive support for our findings.

PRIMARY FUNDING SOURCE

National Institute on Aging and Veterans Health Administration.

Evaluating Montréal's harm reduction interventions for people who inject drugs: protocol for observational study and cost-effectiveness analysis

INTRODUCTION

The main harm reduction interventions for people who inject drugs (PWID) are supervised injection facilities, needle and syringe programmes and opioid agonist treatment. Current evidence supporting their implementation and operation underestimates their usefulness by excluding skin, soft tissue and vascular infections (SSTVIs) and anoxic/toxicity-related brain injury from cost-effectiveness analyses (CEA). Our goal is to conduct a comprehensive CEA of harm reduction interventions in a setting with a large, dispersed, heterogeneous population of PWID, and include prevention of SSTVIs and anoxic/toxicity-related brain injury as measures of benefit in addition to HIV, hepatitis C and overdose morbidity and mortalities averted.

METHODS AND ANALYSIS

This protocol describes how we will develop an open, retrospective cohort of adult PWID living in Québec between 1 January 2009 and 31 December 2020 using administrative health record data. By complementing this data with non-linkable paramedic dispatch records, regional monthly needle and syringe dispensation counts and repeated cross-sectional biobehavioural surveys, we will estimate the hazards of occurrence and the impact of Montréal's harm reduction interventions on the incidence of drug-use-related injuries, infections and deaths. We will synthesise results from our empirical analyses with published evidence to simulate infections and injuries in a hypothetical population of PWID in Montréal under different intervention scenarios including current levels of use and scale-up, and assess the cost-effectiveness of each intervention from the public healthcare payer's perspective.

ETHICS AND DISSEMINATION

This study was approved by McGill University's Institutional Review Board (Study Number: A08-E53-19B). We will work with community partners to disseminate results to the public and scientific community via scientific conferences, a publicly accessible report, op-ed articles and open access peer-reviewed journals.

Estimating the causal effect of transient anemia status on renal and cardiovascular outcomes in community-dwelling patients in Japan at the beginning of impaired renal function using marginal structural modeling

Background

Anemia status may be transient. Causal associations between changes in anemia status over time and adverse outcome development are not well characterized in community-dwelling subjects at the beginning of impaired kidney function.

Methods

This retrospective cohort study used annual health checkup and medical and pharmacy claims data from the JMDC between January 2005 and June 2019. Community-dwelling subjects in Japan with a pre-index estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73 m² followed by a subsequent eGFR < 60 mL/min/1.73 m² (index) were included. The composite renal outcome was ≥ 30% eGFR reduction over 3 years from baseline, serum creatinine doubling, progression to chronic dialysis, kidney transplantation, or eGFR < 15 mL/min/1.73 m². The composite cardiovascular outcome was fatal and non-fatal unstable angina, myocardial infarction, heart failure, or cerebrovascular event. Time-dependent anemia risk was evaluated using Breslow’s estimator and marginal structural Cox models (MSM).

Results

In 32,870 included subjects, 1,396 had anemia at baseline. Adverse outcome incidence was higher in the baseline anemic group, but absolute differences in renal and cardiovascular outcomes between groups were diminished after adjusting for baseline characteristics. In MSM, time-dependent anemia status was associated with higher risk of renal (hazard ratio [95% confidence interval]; 2.6 [1.7–3.8]) and cardiovascular (1.6 [1.2–2.2]) outcomes and mortality (2.8 [1.8–4.3]). Absolute differences in survival probabilities were retained over time but were clinically marginal (1.1–2.7% over 6 years).

Conclusions

Even in subjects at the very early stage of impaired kidney function, early detection and treatment of anemia may help reduce the development of negative sequelae.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10157-021-02137-1.

Socioeconomic inequalities in treatment and relative survival among patients with diffuse large B-cell lymphoma: a Hong Kong population-based study

The influence of socioeconomic status (SES) on access to standard chemotherapy and/or monoclonal antibody therapy, and associated secular trends, relative survival, and excess mortality, among diffuse large B-cell lymphoma (DLBCL) patients is not clear. We conducted a Hong Kong population-based cohort study and identified adult patients with histologically diagnosed DLBCL between 2000 and 2018. We examined the association of SES levels with the odds and the secular trends of receipt of chemotherapy and/or rituximab. Additionally, we estimated the long-term relative survival by SES utilizing Hong Kong life tables. Among 4017 patients with DLBCL, 2363 (58.8%) patients received both chemotherapy and rituximab and 740 (18.4%) patients received chemotherapy alone, while 1612 (40.1%) and 914 (22.8%) patients received no rituximab or chemotherapy, respectively. On multivariable analysis, low SES was associated with lesser use of chemotherapy (odd ratio [OR] 0.44; 95% CI 0.34-0.57) and rituximab (OR 0.41; 95% CI 0.32-0.52). The socioeconomic disparity for either treatment showed no secular trend of change. Additionally, patients with low SES showed increased excess mortality, with a hazard ratio of 2.34 (95% CI 1.67-3.28). Improving survival outcomes for patients with DLBCL requires provision of best available medical care and securing access to treatment regardless of patients' SES.

Tofacitinib versus tocilizumab in the treatment of biological-naïve or previous biological-failure patients with methotrexate-refractory active rheumatoid arthritis

Objectives

To compare effectiveness between tofacitinib and tocilizumab treatments for biological disease-modifying antirheumatic drug (bDMARD)-naïve patients or previous bDMARD-failure patients with active rheumatoid arthritis (RA) refractory to methotrexate (MTX).

Methods

We used two ongoing real-world registries of patients with RA who had first started tofacitinib or tocilizumab between August 2013 and February 2019 at our institutions. Clinical disease activity index (CDAI)-based improvements at 12 months were used for comparisons between tofacitinib and tocilizumab treatments, separately for bDMARD-naïve and previous bDMARD-failure patients.

Results

A total of 464 patients with RA with high or moderate CDAI were enrolled (247 with tofacitinib and 217 with tocilizumab). After adjustments for treatment-selection bias by propensity score matching, we showed that tofacitinib was more likely to induce and maintain ≥85% improvement in CDAI (CDAI85), CDAI70 and remission at 12 months compared with tocilizumab in bDMARD-naïve patients. After adjusting for concurrent use of MTX and prednisolone, the ORs of tofacitinib versus tocilizumab were 3.88 (95% CI 1.87 to 8.03) for CDAI85, 2.89 (95% CI 1.43 to 5.84) for CDAI70 and 3.31 (95% CI 1.69 to 6.48) for remission. These effects were not observed in bDMARD-failure patients. In tofacitinib treatment for bDMARD-failure patients, the number of previously failed bDMARD classes was not associated with CDAI-based improvements. The rate of overall adverse events was similar between both treatments. Similar ORs were obtained from patients adjusted by inverse probability of treatment weighting.

Conclusions

Compared with tocilizumab, tofacitinib can induce greater improvements during the first 12-month treatment in bDMARD-naïve patients, but this difference was not observed in previous bDMARD-failure patients.

A counterfactual approach on the effect of metabolic syndrome on tooth loss: A population-based study

BACKGROUND

This study aimed to investigate the effect of metabolic syndrome (MetS) on tooth loss in adults from a population-based sample.

METHODS

Cross-sectional analysis based on data from a cohort study (2009-2014) with adults from Southern Brazil. MetS (exposure), lack of functional dentition and number of lost teeth (outcomes) were assessed using self-reported, lab and clinical data. Possible confounders included sex, age, family income, educational level, smoking status and sugar consumption. The effect of MetS on the outcomes was estimated using conventional logistic or negative binomial regression models. Marginal structural modeling (MSM) with stabilized weights (a counterfactual analytical method) was also used to enhance group comparability and estimate causal effects.

RESULTS

1,283 participants had available information for the outcomes. Individuals with MetS were more likely to experience a lack of functional dentition than those without MetS [odds ratio (OR) from logistic regression 1.7, 95% CI 1.0-2.9; OR from MSM 3.2, 95% CI 2.3-4.6]. Moreover, the number of teeth lost was 20% higher in participants with MetS compared to those without MetS in conventional analysis (mean ratio [MR] 1.2, 95% CI 1.1- 1.3). The MR increased to 1.7 (95% CI 1.5-2.0) when using MSM.

CONCLUSION

Our findings provide evidence on the effect of MetS on tooth loss. This article is protected by copyright. All rights reserved.

The impact of statins on coronary atherosclerosis progression and long-term cardiovascular disease risk in rheumatoid arthritis

OBJECTIVES

To evaluate whether statins lower cardiovascular disease (CVD) risk in rheumatoid arthritis (RA) and if tentative benefits are related to changes in coronary plaque burden or composition.

METHODS

In an observational cohort study, 150 patients without CVD underwent coronary atherosclerosis evaluation (total, noncalcified, partially and fully calcified plaque) with computed tomography angiography. Prespecified cardiovascular events including cardiac death, myocardial infarction, unstable angina, revascularization, stroke, claudication, and heart failure were prospectively recorded. Change in plaque burden and composition was re-assessed in 102 patients within 6.9±0.3 years.

RESULTS

Time varying statin therapy, modeled using inverse probability treatment and censoring weights, did not significantly attenuate CVD risk in RA overall (adjusted- OR = 0.39 [95%CI=0.15-1.07], p = 0.067). However, statins associated with lower CVD risk in patients with baseline CRP>0.5mg/dL (adjusted-OR=0.09 [95%CI=0.03-0.30], p < 0.001) but not in those with CRP<0.5mg/dL (p-interaction=0.023), after controlling for Framingham-CVD score and time-varying bDMARD use. In patients treated with statin >50% of follow-up time, CRP did not associate with new plaque formation (adjusted-OR=0.42 [95%CI=0.09-1.94]), in contrast to statin-naïve (adjusted-OR=1.89 [95%CI=1.41-2.54]) and statin-treated <50% time (adjusted-OR=1.41 [95%CI=1.03-1.95], p-interaction=0.029). Statin therapy >50% follow-up time predicted dissipation (adjusted-OR=5.84 [95%CI=1.29-26.55]) and calcification of prevalent noncalcified lesions (adjusted-OR=4.16 [95%CI=1.11-15.54]), as well as new calcified plaque formation in segments without baseline plaque (adjusted-OR=2.84 [95%CI=1.09-7.41]).

CONCLUSION

Statin therapy associated with lower long-term cardiovascular risk in RA patients with higher inflammation. Moreover, statin therapy modified the impact of inflammation on new coronary plaque formation and predicted both regression and calcification of prevalent noncalcified lesions.

Association Between Attempted Arteriovenous Fistula Creation and Mortality in People Starting Hemodialysis via a Catheter: A Multicenter, Retrospective Cohort Study

Background:

In North America, most people start hemodialysis via a central venous catheter (“catheter”). These patients are counseled to undergo arteriovenous fistula (“fistula”) creation within weeks of starting hemodialysis because fistulas are associated with improved survival.

Objectives:

To determine whether attempting to create a fistula in patients who start hemodialysis via a catheter is associated with improved mortality. We also sought to determine whether differences in baseline patient characteristics, vascular procedures for access-related complications, or days in hospital may confound or mediate the relationship between attempted fistula creation and mortality.

Design:

Multicenter, retrospective cohort study.

Setting:

Six dialysis programs located in Ontario, Alberta, and Manitoba.

Patients:

Patients aged ≥18 years who initiated hemodialysis via a catheter between January 1, 2004, and May 31, 2012, who had not had a previous attempt at fistula creation. We excluded those who had a life expectancy less than 1 year, who transitioned to peritoneal dialysis within 6 months of starting dialysis, and people who started hemodialysis via a graft.

Measurements:

Attempted fistula creation, all-cause mortality, patient characteristics and comorbidities, vascular procedures for access-related complications, and days spent in hospital.

Methods:

We used survival methods, including marginal structural models, to account for immortal time bias and time-varying confounding.

Results:

In total, 1832 patients initiated hemodialysis via a catheter during the study period and met inclusion criteria. Of these patients, 565 (31%) underwent an attempt at fistula creation following hemodialysis start. As compared to those who did not receive a fistula attempt, these people were younger, had fewer comorbidities, and were more likely to have started dialysis as an outpatient and to have received pre-dialysis care. In a marginal structural model controlling for baseline characteristics and comorbidities, attempted fistula creation was associated with a significantly lower mortality (hazard ratio [HR] = 0.53; 95% confidence interval [CI] = 0.43-0.66). This effect did not appear to be confounded or mediated by differences in the number of days spent in hospital or vascular procedures for access-related complications. It also remained similar in analyses restricted to patients who survived at least 6 months (HR = 0.60; 95% CI = 0.47-0.77) and to patients who started hemodialysis as an outpatient (HR = 0.48; 95% CI = 0.33-0.68).

Limitations:

There is likely residual confounding and treatment selection bias.

Conclusions:

In this multicenter cohort study, attempting fistula creation in people who started hemodialysis via a catheter was associated with significantly reduced mortality. This reduction in mortality could not be explained by differences in patient characteristics or comorbidities, days spent in hospital, or vascular procedures for access-related complications. Residual confounding or selection bias may explain the observed benefits of fistulas for hemodialysis access.

Trial Registration:

Not applicable (cohort study).

Attributable nephrotoxicity of vancomycin in critically ill patients: a marginal structural model study

BACKGROUND

Although vancomycin nephrotoxicity is recognizable, critically ill patients have other potential reasons for acute kidney injury (AKI) and determining its attributable nephrotoxic risk in this population can be cumbersome.

OBJECTIVES

To determine the risk of AKI attributable to vancomycin, controlling for baseline and time-dependent confounders.

METHODS

Time-fixed and daily time-varying variables were extracted from a large public database. The exposures analysed were: (i) IV vancomycin; (ii) serum trough level greater than 15 and 20 mg/L; and (iii) concomitant exposure to vancomycin and piperacillin/tazobactam or other antipseudomonal β-lactams. Censoring and exposure inverse probability of treatment weighting were calculated. Marginal structural models were plotted to evaluate AKI, severe AKI (stage 2/3) and need of renal replacement therapy (RRT).

RESULTS

A total of 26 865 patients were included; 19.7% received vancomycin during ICU stay. After adjusting for fixed and time-variable confounders, vancomycin exposure was associated with AKI (HR = 1.24, 95% CI = 1.09-1.38), but not with severe AKI or need of RRT (HR = 1.05, 95% CI = 0.91-1.23 and HR = 0.97, 95% CI = 0.74-1.29, respectively). A serum trough level greater than 20 mg/L was associated with AKI (HR = 1.90, 95% CI = 1.52-2.30) and severe AKI (HR = 1.69, 95% CI = 1.31-2.19), but showed no statistically significant association with need of RRT (HR = 1.48, 95% CI = 0.92-2.56). The vancomycin + piperacillin/tazobactam combination was not associated with a greater risk than vancomycin alone.

CONCLUSIONS

The attributable nephrotoxicity of vancomycin in critically ill patients is significantly lower than previously suggested and severe AKI is related to vancomycin only when trough serum levels are greater than 20 mg/L.

Uncontrolled Pain and Risk for Depression and Behavioral Symptoms in Residents With Dementia

OBJECTIVES

Limited cohort studies have assessed the association between uncontrolled pain and risk for behavioral and psychological symptoms of dementia (BPSDs). We conducted a longitudinal cohort study to examine whether associations exist between uncontrolled pain and risk for 2 common BPSDs-depression and behavioral symptoms-among long-term care (LTC) residents with Alzheimer disease and related dementia (ADRD).

DESIGN

This retrospective cohort study analyzed quarterly data from the 5% Medicare sample linked to Minimum Data Set (MDS) 3.0 between January 1, 2011, and December 31, 2015.

SETTING AND PARTICIPANTS

LTC residents aged 50 years or older with ADRD who had chronic pain and at least 2 quarterly MDS 3.0 assessments.

METHODS

LTC residents were followed up quarterly from first observed quarterly MDS 3.0 until first outcome event or last observed quarterly MDS 3.0. Uncontrolled pain was defined as numerical rating scale >4, verbal descriptor scale of moderate or severe pain, or ≥1 pain indicators on the Checklist of Nonverbal Pain Indicators. Depression was defined as ≥10 on the Patient Health Questionnaire 9; behavioral symptoms were defined as the presence of psychotic (delusions or hallucinations) or disruptive behaviors (rejection of care, or physical, verbal, or other aggressive behaviors). Generalized linear models (GLMs) with marginal structural modeling (MSM) stabilized weights were used to examine uncontrolled pain and outcome risk.

RESULTS

The incidence rate of depression and behavioral symptoms during follow-up was 9.4 and 23.1 per 100 resident-years, respectively. Results from the MSM-GLMs showed that LTC residents with uncontrolled pain had a higher risk than those with controlled pain for developing depression [hazard ratio 1.67, 95% confidence interval (CI) 1.54-1.81] and behavioral symptoms (hazard ratio 1.28, 95% CI 1.19-1.37).

CONCLUSIONS AND IMPLICATIONS

Uncontrolled pain was associated with elevated risk for depressive and behavioral symptoms in dementia, underscoring the importance of pain assessment and control among LTC residents with ADRD.

Pharmacoepidemiology for nephrologists (part 2): potential biases and how to overcome them

Observational pharmacoepidemiological studies using routinely collected healthcare data are increasingly being used in the field of nephrology to answer questions on the effectiveness and safety of medications. This review discusses a number of biases that may arise in such studies and proposes solutions to minimize them during the design or statistical analysis phase. We first describe designs to handle confounding by indication (e.g. active comparator design) and methods to investigate the influence of unmeasured confounding, such as the E-value, the use of negative control outcomes and control cohorts. We next discuss prevalent user and immortal time biases in pharmacoepidemiology research and how these can be prevented by focussing on incident users and applying either landmarking, using a time-varying exposure, or the cloning, censoring and weighting method. Lastly, we briefly discuss the common issues with missing data and misclassification bias. When these biases are properly accounted for, pharmacoepidemiological observational studies can provide valuable information for clinical practice.

Using marginal structural models to analyze the impact of subsequent therapy on the treatment effect in survival data: Simulations and clinical trial examples

We explore the impact of time-varying subsequent therapy on the statistical power and treatment effects in survival analysis. The marginal structural model (MSM) with stabilized inverse probability treatment weights (sIPTW) was used to account for the effects due to the subsequent therapy. Simulations were performed to compare the MSM-sIPTW method with the conventional method without accounting for the time-varying covariate such as subsequent therapy that is dependent on the initial response of the treatment effect. The results of the simulations indicated that the statistical power, thereby the Type I error, of the trials to detect the frontline treatment effect could be inflated if no appropriate adjustment was made for the impact due to the add-on effects of the subsequent therapy. Correspondingly, the hazard ratio between the treatment groups may be overestimated by the conventional analysis methods. In contrast, MSM-sIPTW can maintain the Type I error rate and gave unbiased estimates of the hazard ratio for the treatment. Two real examples were used to discuss the potential clinical implications. The study demonstrated the importance of accounting for time-varying subsequent therapy for obtaining unbiased interpretation of data.

Association of Preeclampsia With Incident Stroke in Later Life Among Women in the Framingham Heart Study

IMPORTANCE

Contemporary research suggests an association between preeclampsia and later-life stroke among women. To our knowledge, no research to date has accounted for the time-varying nature of shared risk factors for preeclampsia and later-life stroke incidence.

OBJECTIVE

To assess the relative risk of incident stroke in later life among women with and without a history of preeclampsia after accounting for time-varying covariates.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study was a secondary analysis of data from the Framingham Heart Study, which was conducted from 1948 to 2016. Women were included in the analysis if they were stroke free at enrollment and had a minimum of 3 study visits and 1 pregnancy before menopause, hysterectomy, or age 45 years. Data on vascular risk factors, history of preeclampsia, and stroke incidence were collected biannually. Participants were followed up until incident stroke or censorship from the study. Marginal structural models were used to evaluate the relative risk of incident stroke among participants with and without a history of preeclampsia after accounting for time-varying covariates. Data were analyzed from May 2019 to December 2020.

EXPOSURES

Presence or absence of preeclampsia among women with 1 or more pregnancies.

MAIN OUTCOMES AND MEASURES

Incident stroke in later life.

RESULTS

A total of 1435 women (mean [SD] age, 44.4 [7.7] years at the beginning of the study; 100% White) with 41 422 person-years of follow-up were included in the analytic sample. Of those, 169 women had a history of preeclampsia, and 231 women experienced strokes during follow-up. At baseline, women with preeclampsia were more likely to be younger, to be receiving cholesterol-lowering medications, to have lower cholesterol and higher diastolic blood pressure, and to currently smoke. The association between preeclampsia and stroke in the marginal structural model was only evident when adjustment was made for all vascular risk factors over the life course, which indicated that women with a history of preeclampsia had a higher risk of stroke in later life compared with women without a history of preeclampsia (relative risk, 3.79; 95% CI, 1.24-11.60).

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that preeclampsia may be a risk factor for later-life stroke among women after adjustment for time-varying vascular and demographic factors. Future research is warranted to fully explore the mediation of this association by midlife vascular risk factors.

Methodological evaluation of bias in observational coronavirus disease 2019 studies on drug effectiveness

Background and objective

Observational studies may provide valuable evidence on real-world causal effects of drug effectiveness in patients with coronavirus disease 2019 (COVID-19). As patients are usually observed from hospital admission to discharge and drug initiation starts during hospitalization, advanced statistical methods are needed to account for time-dependent drug exposure, confounding and competing events. Our objective is to evaluate the observational studies on the three common methodological pitfalls in time-to-event analyses: immortal time bias, confounding bias and competing risk bias.

Methods

We performed a systematic literature search on 23 October 2020, in the PubMed database to identify observational cohort studies that evaluated drug effectiveness in hospitalized patients with COVID-19. We included articles published in four journals: British Medical Journal, New England Journal of Medicine, Journal of the American Medical Association and The Lancet as well as their sub-journals.

Results

Overall, out of 255 articles screened, 11 observational cohort studies on treatment effectiveness with drug exposure–outcome associations were evaluated. All studies were susceptible to one or more types of bias in the primary study analysis. Eight studies had a time-dependent treatment. However, the hazard ratios were not adjusted for immortal time in the primary analysis. Even though confounders presented at baseline have been addressed in nine studies, time-varying confounding caused by time-varying treatment exposure and clinical variables was less recognized. Only one out of 11 studies addressed competing event bias by extending follow-up beyond patient discharge.

Conclusions

In the observational cohort studies on drug effectiveness for treatment of COVID-19 published in four high-impact journals, the methodological biases were concerningly common. Appropriate statistical tools are essential to avoid misleading conclusions and to obtain a better understanding of potential treatment effects.

Are there non-linear relationships between alcohol consumption and long-term health? Protocol for a systematic review of observational studies employing approaches to improve causal inference

INTRODUCTION

There is a substantial literature finding that moderate alcohol consumption is protective against certain health conditions. However, more recent research has highlighted the possibility that these findings are methodological artefacts, caused by confounding and other biases. While modern analytical and study design approaches can mitigate confounding and thus enhance causal inference in observational studies, they are not routinely applied in research assessing the relationship between alcohol use and long-term health outcomes. The purpose of this systematic review is to identify observational studies that employ these analytical/design-based approaches in assessing whether relationships between alcohol consumption and health outcomes are non-linear. This review seeks to evaluate, on a per-outcome basis, what these studies find the strength and form of the relationship between alcohol consumption and health to be.

METHODS AND ANALYSIS

Electronic databases (MEDLINE, PsycINFO, Embase and SCOPUS) were searched in May 2020. Study selection will comply with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Articles will be screened against eligibility criteria intended to capture studies using observational data to assess the relationship between varying levels of alcohol exposure and any long-term health outcome (actual or surrogate), and that have employed at least one of the prespecified approaches to enhancing causal inference. Risk of bias of included articles will be assessed using study design-specific tools. A narrative synthesis of the results is planned.

ETHICS AND DISSEMINATION

Formal ethics approval is not required given there will be no primary data collection. The results of the study will be disseminated through published manuscripts, conferences and seminar presentations.

PROSPERO REGISTRATION NUMBER

CRD42020185861.

Cavitary Coccidioidomycosis: Impact of azole antifungal therapy

Approximately 5 to 15% of patients with pulmonary coccidioidomycosis subsequently develop pulmonary cavities. These cavities may resolve spontaneously over a number of years; however, some cavities never close, and a small proportion causes complications such as hemorrhage, pneumothorax or empyema. The impact of azole antifungal treatment on coccidioidal cavities has not been studied. Because azoles are a common treatment for symptomatic pulmonary coccidioidomycosis, we aimed to assess the impact of azole therapy on cavity closure. From January 1, 2004, through December 31, 2014, we retrospectively identified 313 patients with cavitary coccidioidomycosis and excluded 42 who had the cavity removed surgically, leaving 271 data sets available for study. Of the 271 patients, 221 (81.5%) received azole therapy during 5-year follow-up; 50 patients did not receive antifungal treatment. Among the 271 patients, cavities closed in 38 (14.0%). Statistical modeling showed that cavities were more likely to close in patients in the treated group than in the nontreated group (hazard ratio, 2.14 [95% CI: 1.45-5.66]). Cavities were less likely to close in active smokers than nonsmokers (11/41 [26.8%] vs 97/182 [53.3%]; P = 0.002) or in persons with than without diabetes (27/74 [36.5%] vs 81/149 [54.4%]; P = 0.01).We did not find an association between cavity size and closure. Our findings provide rationale for further study of treatment protocols in this subset of patients with coccidioidomycosis.

LAY SUMMARY

Coccidioidomycosis, known as valley fever, is a fungal infection that infrequently causes cavities to form in the lungs, which potentially results in long-term lung symptoms. We learned that cavities closed more often in persons who received antifungal drugs, but most cavities never closed completely.