Subgroup analysis and other (mis)uses of baseline data in clinical trials

Metformin for low back pain: Study protocol for a randomised, double-blind, placebo-controlled trial

Background

Chronic low back pain is a major cause of pain and disability with limited effective therapies. Metformin is a safe, inexpensive, well-tolerated drug that has pleotropic effects, including effects on pain pathways that may influence low back pain. The aim of this randomised, double-blind, placebo-controlled trial is to determine whether metformin reduces low back pain over 4 months in individuals with chronic low back pain.

Methods and analysis

One hundred and twenty-three participants with chronic low back pain will be recruited from the community in Melbourne, Australia, and randomly allocated in a 1:1 ratio to receive either metformin 2g or identical placebo daily for 4 months. The primary outcome will be change in pain intensity assessed using a 100 ​mm visual analogue scale at 4 months and the secondary outcomes will be change in low back disability, physical activity and narcotic use. Adverse events will be recorded. The primary analysis will be by intention to treat.

Discussion

Given the societal burden of LBP and the limited effective treatment options available, this study that evaluates the efficacy of metformin in LBP, if proves to be effective, will offer an important therapeutic approach for this disabling condition.

Ethics and dissemination

Ethics approval has been obtained from the Alfred Hospital Ethics Committee (392/21) and Monash University Human Research Ethics Committee (30607). Written informed consent will be obtained from all the participants. The findings will be disseminated through peer-review publications and conference presentations.

Trial registration

Australian New Zealand Clinical Trials Registry, ACTRN12621001453875 (registered 25th October 2021).

Semi-supervised learning from small annotated data and large unlabeled data for fine-grained Participants, Intervention, Comparison, and Outcomes entity recognition

OBJECTIVE

Extracting PICO elements-Participants, Intervention, Comparison, and Outcomes-from clinical trial literature is essential for clinical evidence retrieval, appraisal, and synthesis. Existing approaches do not distinguish the attributes of PICO entities. This study aims to develop a named entity recognition (NER) model to extract PICO entities with fine granularities.

MATERIALS AND METHODS

Using a corpus of 2511 abstracts with PICO mentions from 4 public datasets, we developed a semi-supervised method to facilitate the training of a NER model, FinePICO, by combining limited annotated data of PICO entities and abundant unlabeled data. For evaluation, we divided the entire dataset into 2 subsets: a smaller group with annotations and a larger group without annotations. We then established the theoretical lower and upper performance bounds based on the performance of supervised learning models trained solely on the small, annotated subset and on the entire set with complete annotations, respectively. Finally, we evaluated FinePICO on both the smaller annotated subset and the larger, initially unannotated subset. We measured the performance of FinePICO using precision, recall, and F1.

RESULTS

Our method achieved precision/recall/F1 of 0.567/0.636/0.60, respectively, using a small set of annotated samples, outperforming the baseline model (F1: 0.437) by more than 16%. The model demonstrates generalizability to a different PICO framework and to another corpus, which consistently outperforms the benchmark in diverse experimental settings (P-value < .001).

DISCUSSION

We developed FinePICO to recognize fine-grained PICO entities from text and validated its performance across diverse experimental settings, highlighting the feasibility of using semi-supervised learning (SSL) techniques to enhance PICO entities extraction. Future work can focus on optimizing SSL algorithms to improve efficiency and reduce computational costs.

CONCLUSION

This study contributes a generalizable and effective semi-supervised approach leveraging large unlabeled data together with small, annotated data for fine-grained PICO extraction.

Unsupervised clustering approach to assess heterogeneity of treatment effects across patient phenotypes in randomized clinical trials

BACKGROUND

Primary results from randomized clinical trials (RCT) only inform on the average treatment effect in the studied population, and it is critical to understand how treatment effect varies across subpopulations. In this paper we describe a clustering-based approach for the assessment of Heterogeneity of Treatment Effect (HTE) over patient phenotypes, which maintains the unsupervised nature of classical subgroup analysis while jointly accounting for relevant patient characteristics.

METHODS

We applied phenotype-based stratification in the ENGAGE AF-TIMI 48 trial, a non-inferiority trial comparing the effects of higher-dose edoxaban regimen (direct anticoagulant) versus warfarin (vitamin K antagonist) on a composite endpoint of stroke and systemic embolism in 14,062 patients with atrial fibrillation.

RESULTS

We identified three distinct phenotypes: non-white participants, mostly from Asia (A); white participants without previous use of vitamin-K antagonists (B); and white participants with previous use of vitamin-K antagonist (C). The effect of the higher-dose edoxaban regimen vs warfarin significantly varied over phenotypes (p for interaction = 0.03) with the strongest benefit in cluster A (HR = 0.72, 95 % CI: 0.52-1.00), moderate effect in cluster B (HR = 0.80, 95 % CI: 0.61, 1.06) and no observed effect in cluster C (HR = 1.01, 95 % CI: 0.80, 1.27).

CONCLUSIONS

Assessing HTE over patients' phenotypes might represent a relevant complement to other stratification approaches to elucidate results from subgroups analyses, especially in those settings where an overwhelming superiority overall effect was not observed. Cluster analysis allows a clear discrimination of patients with direct interpretability of who are the patients that would most benefit from the investigated strategy or treatment.

Amygdala activity after subchronic escitalopram administration in healthy volunteers: A pharmaco-functional magnetic resonance imaging study

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) are used for the treatment of several conditions including anxiety disorders, but the basic neurobiology of serotonin function remains unclear. The amygdala and prefrontal cortex are strongly innervated by serotonergic projections and have been suggested to play an important role in anxiety expression. However, serotonergic function in behaviour and SSRI-mediated neurobiological changes remain incompletely understood.

AIMS

To investigate the neural correlates of subchronic antidepressant administration.

METHODS

We investigated whether the 2- to 3-week administration of a highly selective SSRI (escitalopram) would alter brain activation on a task robustly shown to recruit the bilateral amygdala and frontal cortices in a large healthy volunteer sample. Participants performed the task during a functional magnetic resonance imaging acquisition before (n = 96) and after subchronic escitalopram (n = 46, days of administration mean (SD) = 15.7 (2.70)) or placebo (n = 40 days of administration mean (SD) = 16.2 (2.90)) self-administration.

RESULTS

Compared to placebo, we found an elevation in right amygdala activation to the task after escitalopram administration without significant changes in mood. This effect was not seen in the left amygdala, the dorsomedial region of interest, the subgenual anterior cingulate cortex or the right fusiform area. There were no significant changes in connectivity between the dorsomedial cortex and amygdala or the subgenual anterior cingulate cortex after escitalopram administration.

CONCLUSIONS

To date, this most highly powered study of subchronic SSRI administration indicates that, contrary to effects often seen in patients with anxiety disorders, subchronic SSRI treatment may increase amygdala activation in healthy controls. This finding highlights important gaps in our understanding of the functional role of serotonin.

A Causal Mediation Approach to Account for Interaction of Treatment and Intercurrent Events: Using Hypothetical Strategy

Hypothetical strategy is a common strategy for handling intercurrent events (IEs). No current guideline or study considers treatment-IE interaction to target the estimand in any one IE-handling strategy. Based on the hypothetical strategy, we aimed to (1) assess the performance of three estimators with different considerations for the treatment-IE interaction in a simulation and (2) compare the estimation of these estimators in a real trial. Simulation data were generalized based on realistic clinical trials of Alzheimer's disease. The estimand of interest was the effect of treatment with no IE occurring under the hypothetical strategy. Three estimators, namely, G-estimation with and without interaction and IE-ignored estimation, were compared in scenarios where the treatment-IE interaction effect was set as -50% to 50% of the main effect. Bias was the key performance measure. The real case was derived from a randomized trial of methadone maintenance treatment. Only G-estimation with interaction exhibited unbiased estimations regardless of the existence, direction or magnitude of the treatment-IE interaction in those scenarios. Neglecting the interaction and ignoring the IE would introduce a bias as large as 0.093 and 0.241 (true value, -1.561) if the interaction effect existed. In the real case, compared with G-estimation with interaction, G-estimation without interaction and IE-ignored estimation increased the estimand of interest by 33.55% and 34.36%, respectively. This study highlights the importance of considering treatment-IE interaction in the estimand framework. In practice, it would be better to include the interaction in the estimator by default.

Six-month outcomes after traumatic brain injury in the Augmented versus Routine Approach to Giving Energy multicentre, double-blind, randomised controlled Trial (TARGET)

BACKGROUND

Critically ill patients with a traumatic brain injury (TBI) may require prolonged intensive care unit (ICU) admission and hence receive greater exposure to hospital enteral nutrition. It is unknown if augmented energy delivery with enteral nutrition during ICU admission impacts quality of life in survivors or gastrointestinal tolerance during nutrition delivery in the ICU.

OBJECTIVES

The objective of this study was to compare health-related quality of life, using the EuroQol five-dimensions five-level visual analogue scale at 6 months, in survivors who presented with a TBI and received augmented energy (1.5 kcal/ml) to those who received routine energy (1.0 kcal/ml). Secondary objectives were to explore differences in total energy and protein delivery, gastrointestinal tolerance, and mortality between groups.

METHODS

Secondary analysis of participants admitted with a TBI in the Augmented versus Routine Approach to Giving Energy Trial (TARGET) randomised controlled trial. Data are represented as n (%) or median (interquartile range).

RESULTS

Of the 3957 patients in TARGET, 231 (5.8%) were admitted after a TBI (augmented = 124; routine = 107). Patients within TARGET who were admitted with a TBI were relatively young (42 [27, 61] years) and received TARGET enteral nutrition for an extended period (9 [5, 15] days). At 6 months, EuroQol five-dimensions five-level quality-of-life scores were available for 166 TBI survivors (72% of TBI cohort randomised, augmented = 97, routine = 69). There was no evidence of a difference in quality of life (augmented = 70 [52, 90]; routine = 70 [55, 85]; median difference augmented vs routine = 0 [95% confidence interval: -5, 10]). TBI participants assigned to augmented energy received more energy with a similar protein than the routine group. Gastrointestinal tolerance was similar between groups.

CONCLUSION

While patients admitted after a TBI received enteral nutrition for an extended period, an increased exposure to augmented energy did not affect survivors' quality-of-life scores.

Interest in and Willingness to Use PrEP: A Cross-Sectional Study of Individuals with Problematic Substance Use Residing in a High HIV Prevalence Jurisdiction

Although it is an effective HIV prevention method, pre-exposure prophylaxis (PrEP) is underutilized in the Southern US. Many people who use drugs (PWUD) have increased susceptibility to HIV which could be lessened by using PrEP. Potential barriers to PrEP use include lack of awareness of PrEP, low knowledge about HIV prevention, low self-efficacy for HIV prevention, inaccurate risk perceptions, and anticipated stigma. The current study examined predisposing, enabling, and reinforcing factors that may predict interest in PrEP. The purpose of the current study was to explore factors associated with interest in and willingness to use daily oral and long acting injectable PrEP among sexually active adult PWUD. The data were collected from adult participants (n = 270) residing in Harris County, TX, who self-reported problematic substance use and who reported oral, anal, or vaginal sex in the six months prior to completing the survey. The survey was distributed and completed online via Qualtrics Panels in March of 2022 and included measures of PrEP and HIV knowledge, PrEP stigma, sexual health self-efficacy, experiences of discrimination, health literacy, and medical mistrust. The majority of participants reported circumstances or behaviors that increased their susceptibility to HIV. Findings indicated that PrEP user stereotypes and PrEP anticipated disapproval by others were associated with interest in using daily oral PrEP and willingness to use long acting injectable PrEP. These results provide insight into reasons for low PrEP uptake among PWUD who live in a high HIV prevalence jurisdiction. Implications for HIV prevention intervention are discussed.

Effects of dexmedetomidine on renal function after cardiac surgery for infective endocarditis: An interim analysis of a randomized controlled trial

BACKGROUND

Patients undergoing cardiac surgery for infective endocarditis (IE) are at a high risk of postoperative acute kidney injury (AKI) owing to heightened systemic inflammation. Therefore, we aimed to investigate the effect of dexmedetomidine on postoperative AKI in patients who underwent cardiac surgery for IE.

METHODS

A total of 63 patients who underwent cardiac surgery for IE were randomly assigned to receive either intravenous dexmedetomidine infusion of 0.4 μg kg-1 h-1 (DEX group) or normal saline infusion (control group) for 24 h after induction of anesthesia. The occurrence of AKI within seven days postoperation, epinephrine, norepinephrine, and interleukin-6 levels, as well as postoperative morbidities, were assessed. An intertrim analysis was conducted using Pocock's alpha spending function at α = 0.05 and β = 0.2.

RESULTS

This trial was early terminated according to the results of interim analysis performed when 60 % of the pre-set number of patients have been collected. The incidence of AKI was significantly lower in the DEX group than in the control group (32.3 % vs. 9.4 %, p = 0.025). Patients in the DEX group had significantly lower epinephrine levels than those in the control group, whereas norepinephrine and interleukin-6 levels were similar. Perioperative mean arterial pressure or heart rate did not differ between the groups.

CONCLUSIONS

Dexmedetomidine administration for 24 h starting from induction of anesthesia significantly reduced the incidence of postoperative AKI after cardiac surgery for IE (by 29 % vs. control) without hemodynamic side effects. This was accompanied by a significant attenuation of postoperative increase in serum epinephrine levels.

Uncovering individualised treatment effects for educational trials

Large-scale Randomised Controlled Trials (RCTs) are widely regarded as "the gold standard" for testing the causal effects of school-based interventions. RCTs typically present the statistical significance of the average treatment effect (ATE), which captures the effect an intervention has had on average for a given population. However, key decisions in child health and education are often about individuals who may be very different from those averages. One way to identify heterogeneous treatment effects across different individuals, not captured by the ATE, is to conduct subgroup analyses. For example, free school meal (FSM) pupils as required for projects funded by the Education Endowment Foundation (EEF) in England. These subgroup analyses, as we demonstrate in 48 EEF-funded RCTs involving over 200,000 students, are usually not standardised across studies and offer flexible degrees of freedom to researchers, potentially leading to mixed, if not misleading, results. Here, we develop and deploy an alternative to ATE and subgroup analysis, a machine-learning and regression-based framework to predict individualised treatment effects (ITEs). ITEs could show where an intervention worked, for which individuals, and to what extent. Our findings have implications for decision-makers in fields like education, healthcare, law, and clinical practices concerning children and adolescents.

Tailoring the treatment of inflammatory rheumatic diseases by a better stratification and characterization of the clinical patient heterogeneity. Findings from a systematic literature review and experts' consensus

Inflammatory rheumatic diseases are different pathologic conditions associated with a deregulated immune response, codified along a spectrum of disorders, with autoinflammatory and autoimmune diseases as two-end phenotypes of this continuum. Despite pathogenic differences, inflammatory rheumatic diseases are commonly managed with a limited number of immunosuppressive drugs, sometimes with partial evidence or transferring physicians' knowledge in different patients. In addition, several randomized clinical trials, enrolling these patients, did not meet the primary pre-established outcomes and these findings could be linked to the underlying molecular diversities along the spectrum of inflammatory rheumatic disorders. In fact, the resulting patient heterogeneity may be driven by differences in underlying molecular pathology also resulting in variable responses to immunosuppressive drugs. Thus, the identification of different clinical subsets may possibly overcome the major obstacles that limit the development more effective therapeutic strategies for these patients with inflammatory rheumatic diseases. This clinical heterogeneity could require a diverse therapeutic management to improve patient outcomes and increase the frequency of clinical remission. Therefore, the importance of better patient stratification and characterization is increasingly pointed out according to the precision medicine principles, also suggesting a new approach for disease treatment. In fact, based on a better proposed patient profiling, clinicians could more appropriately balance the therapeutic management. On these bases, we synthetized and discussed the available literature about the patient profiling in regard to therapy in the context of inflammatory rheumatic diseases, mainly focusing on randomized clinical trials. We provided an overview of the importance of a better stratification and characterization of the clinical heterogeneity of patients with inflammatory rheumatic diseases identifying this point as crucial in improving the management of these patients.

Are there patients with an intracapsular fracture of the hip who may benefit from an uncemented hemiarthroplasty?

Aims

Cemented hemiarthroplasty is an effective form of treatment for most patients with an intracapsular fracture of the hip. However, it remains unclear whether there are subgroups of patients who may benefit from the alternative operation of a modern uncemented hemiarthroplasty - the aim of this study was to investigate this issue. Knowledge about the heterogeneity of treatment effects is important for surgeons in order to target operations towards specific subgroups who would benefit the most.

Methods

We used causal forest analysis to compare subgroup- and individual-level treatment effects between cemented and modern uncemented hemiarthroplasty in patients aged > 60 years with an intracapsular fracture of the hip, using data from the World Hip Trauma Evaluation 5 (WHiTE 5) multicentre randomized clinical trial. EuroQol five-dimension index scores were used to measure health-related quality of life at one, four, and 12 months postoperatively.

Results

Our analysis revealed a complex landscape of responses to the use of a cemented hemiarthroplasty in the 12 months after surgery. There was heterogeneity of effects with regard to baseline characteristics, including age, pre-injury health status, and lifestyle factors such as alcohol consumption. This heterogeneity was greater at the one-month mark than at subsequent follow-up timepoints, with particular regard to subgroups based on age. However, for all subgroups, the effect estimates for quality of life lay within the confidence intervals derived from the analysis of all patients.

Conclusion

The use of a cemented hemiarthroplasty is expected to increase health-related quality of life compared with modern uncemented hemiarthroplasty for all subgroups of patients aged > 60 years with a displaced intracapsular fracture of the hip.

Predicting subgroup treatment effects for a new study: Motivations, results and learnings from running a data challenge in a pharmaceutical corporation

We present the motivation, experience, and learnings from a data challenge conducted at a large pharmaceutical corporation on the topic of subgroup identification. The data challenge aimed at exploring approaches to subgroup identification for future clinical trials. To mimic a realistic setting, participants had access to 4 Phase III clinical trials to derive a subgroup and predict its treatment effect on a future study not accessible to challenge participants. A total of 30 teams registered for the challenge with around 100 participants, primarily from Biostatistics organization. We outline the motivation for running the challenge, the challenge rules, and logistics. Finally, we present the results of the challenge, the participant feedback as well as the learnings. We also present our view on the implications of the results on exploratory analyses related to treatment effect heterogeneity.

Description of subgroup reporting in clinical trials of chronic diseases: a meta-epidemiological study

INTRODUCTION

In trials, subgroup analyses are used to examine whether treatment effects differ by important patient characteristics. However, which subgroups are most commonly reported has not been comprehensively described.

DESIGN AND SETTINGS

Using a set of trials identified from the US clinical trials register (ClinicalTrials.gov), we describe every reported subgroup for a range of conditions and drug classes.

METHODS

We obtained trial characteristics from ClinicalTrials.gov via the Aggregate Analysis of ClinicalTrials.gov database. We subsequently obtained all corresponding PubMed-indexed papers and screened these for subgroup reporting. Tables and text for reported subgroups were extracted and standardised using Medical Subject Headings and WHO Anatomical Therapeutic Chemical codes. Via logistic and Poisson regression models we identified independent predictors of result reporting (any vs none) and subgroup reporting (any vs none and counts). We then summarised subgroup reporting by index condition and presented all subgroups for all trials via a web-based interactive heatmap (https://ihwph-hehta.shinyapps.io/subgroup_reporting_app/).

RESULTS

Among 2235 eligible trials, 23% (524 trials) reported subgroups. Follow-up time (OR, 95%CI: 1.13, 1.04-1.24), enrolment (per 10-fold increment, 3.48, 2.25-5.47), trial starting year (1.07, 1.03-1.11) and specific index conditions (eg, hypercholesterolaemia, hypertension, taking asthma as the reference, OR ranged from 0.15 to 10.44), predicted reporting, sponsoring source and number of arms did not. Results were similar on modelling any result reporting (except number of arms, 1.42, 1.15-1.74) and the total number of subgroups. Age (51%), gender (45%), racial group (28%) were the most frequently reported subgroups. Characteristics related to the index condition (severity/duration/types etc) were frequently reported (eg, 69% of myocardial infarction trials reported on its severity/duration/types). However, reporting on comorbidity/frailty (five trials) and mental health (four trials) was rare.

CONCLUSION

Other than age, sex, race ethnicity or geographic location and characteristics related to the index condition, information on variation in treatment effects is sparse.

PROSPERO REGISTRATION NUMBER

CRD42018048202.

Opioid Risk Tool, in-hospital opioid exposure, and opioid demand predict pain outcomes following traumatic injury

Prescribed opioids are a mainstay pain treatment after traumatic injury, but a subgroup of patients may be at risk for continued opioid use. We evaluated the predictive utility of a traditional screening tool, the Opioid Risk Tool (ORT), and two other measures: average in-hospital milligram morphine equivalents (MME) per day and an assessment of opioid demand in predicting pain outcomes. Assessments of pain-related outcomes (pain intensity, interference, injury-related stress, and need for additional pain treatment) were administered at 2 weeks and 12 months post-discharge in a sample of 34 patients hospitalized for traumatic injury. Bayesian linear models were used to evaluate changes in responses over time as a function of predictors. High-risk ORT, higher MME per day, and greater opioid demand predicted less change in outcomes over time. This report provides first evidence that malleable factors of opioid and opioid demand have utility in predicting pain outcomes following traumatic injury.

Individualized Treatment Effect Prediction with Machine Learning - Salient Considerations

BACKGROUND

Machine learning-based approaches that seek to accomplish individualized treatment effect prediction have gained traction; however, some salient challenges lack wider recognition.

METHODS

We describe key methodologic considerations for individualized treatment effect prediction models using data from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist Trial for spironolactone in heart failure with preserved ejection fraction. The causal survival forest algorithm was used for model development. Calibration and discrimination were evaluated using a bootstrapping-based internal validation procedure. Observed benefits were described for predicted benefit quartiles and quartiles of a known effect modifier: ejection fraction. A negative control analysis with noncardiovascular death as the outcome was implemented to detect confounding.

RESULTS

Among 3445 participants, 671 events occurred over a median of 3.3 years of follow-up. In internal validation, a higher average observed benefit was noted among patients in the highest quartile of predicted benefit. The median (interquartile range) of the observed restricted mean survival time difference at 3.3 years at the highest quartile of model-predicted benefit was 62 days (32 to 83) and was 47 days (26 to 67) at the lowest quartile of ejection fraction. Body-mass index had higher contribution to prediction of benefit relative to other included measures (33.7% vs. glomerular filtration rate [27.3%], ejection fraction [15.1%], and younger age [12.8%]) No benefit was observed for noncardiovascular death at higher model-predicted benefit quartiles, although benefit for noncardiovascular death was observed at lower quartiles.

CONCLUSIONS

Carefully applied and validated predictive models hold promise in identifying heterogeneous treatment effects and are useful for hypothesis generation regarding the role of phenotypic characteristics in modifying the benefit of experimental interventions in clinical trials. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT00094302.).

Do medications increase the efficacy of digital interventions for smoking cessation? Secondary results from the iCanQuit randomized trial

BACKGROUND AND AIMS

iCanQuit is a smartphone application (app) proven efficacious for smoking cessation in a Phase III randomized controlled trial (RCT). This study aimed to measure whether medications approved by the US Food and Drug Administration (FDA) for smoking cessation would further enhance the efficacy of iCanQuit, relative to its parent trial comparator-the National Cancer Institute's (NCI's) QuitGuide app.

DESIGN

Secondary analysis of the entire parent trial sample of a two-group (iCanQuit and QuitGuide), stratified, doubled-blind RCT.

SETTING

United States.

PARTICIPANTS

Participants who reported using an FDA-approved cessation medication on their own (n = 619) and those who reported no use of cessation medications (n = 1469).

INTERVENTIONS

Participants were randomized to receive iCanQuit app or NCI's QuitGuide app.

MEASUREMENTS

Use of FDA-approved medications was measured at 3 months post-randomization. Smoking cessation outcomes were measured at 3, 6 and 12 months. The primary outcome was 12-month self-reported 30-day point prevalence abstinence (PPA).

FINDINGS

The data retention rate at the 12-month follow-up was 94.0%. Participants were aged 38.5 years, 71.0% female, 36.6% minority race/ethnicity, 40.6% high school or less education, residing in all 50 US States and smoking 19.2 cigarettes/day. The 29.6% of all participants who used medications were more likely to choose nicotine replacement therapy (NRT; 78.8%) than other cessation medications (i.e. varenicline or bupropion; 18.3 and 10.5%, respectively) and use did not differ by app treatment assignment (all P > 0.05). There was a significant (P = 0.049) interaction between medication use and app treatment assignment on PPA. Specifically, 12-month quit rates were 34% for iCanQuit versus 20% for QuitGuide [odds ratio (OR) = 2.36, 95% confidence interval (CI) = 1.59, 3.49] among participants reporting any medication use, whereas among participants reporting no medication use, quit rates were 28% for iCanQuit versus 22% for QuitGuide (OR = 1.41, 95% CI = 1.09, 1.82). Results were stronger for those using only NRT: 40% quit rates for iCanQuit versus 18% quit rates for QuitGuide (OR = 3.57, 95% CI = 2.20, 5.79).

CONCLUSIONS

The iCanQuit smartphone app for smoking cessation was more efficacious than the QuitGuide smartphone app, regardless of whether participants used medications to aid cessation. Smoking cessation medications, especially nicotine replacement therapy, might enhance the efficacy of the iCanQuit app.

Heterogeneity of Benefit from Earlier Time-to-Antibiotics for Sepsis

Rationale: Shorter time-to-antibiotics improves survival from sepsis, particularly among patients in shock. There may be other subgroups for whom faster antibiotics are particularly beneficial.Objectives: Identify patient characteristics associated with greater benefit from shorter time-to-antibiotics.Methods: Observational cohort study of patients hospitalized with community-onset sepsis at 173 hospitals and treated with antimicrobials within 12 hours. We used three approaches to evaluate heterogeneity of benefit from shorter time-to-antibiotics: 1) conditional average treatment effects of shorter (⩽3 h) versus longer (>3-12 h) time-to-antibiotics on 30-day mortality using multivariable Poisson regression; 2) causal forest to identify characteristics associated with greatest benefit from shorter time-to-antibiotics; and 3) logistic regression with time-to-antibiotics modeled as a spline.Measurements and Main Results: Among 273,255 patients with community-onset sepsis, 131,094 (48.0%) received antibiotics within 3 hours. In Poisson models, shorter time-to-antibiotics was associated with greater absolute mortality reduction among patients with metastatic cancer (5.0% [95% confidence interval; CI: 4.3-5.7] vs. 0.4% [95% CI: 0.2-0.6] for patients without cancer, P < 0.001); patients with shock (7.0% [95% CI: 5.8-8.2%] vs. 2.8% [95% CI: 2.7-3.5%] for patients without shock, P = 0.005); and patients with more acute organ dysfunctions (4.8% [95% CI: 3.9-5.6%] for three or more dysfunctions vs. 0.5% [95% CI: 0.3-0.8] for one dysfunction, P < 0.001). In causal forest, metastatic cancer and shock were associated with greatest benefit from shorter time-to-antibiotics. Spline analysis confirmed differential nonlinear associations of time-to-antibiotics with mortality in patients with metastatic cancer and shock.Conclusions: In patients with community-onset sepsis, the mortality benefit of shorter time-to-antibiotics varied by patient characteristics. These findings suggest that shorter time-to-antibiotics for sepsis is particularly important among patients with cancer and/or shock.

Cost-effectiveness of prehabilitation of elderly frail or pre-frail patients prior to elective surgery (PRAEP-GO) versus usual care - Protocol for a health economic evaluation alongside a randomized controlled trial

BACKGROUND

Prehabilitation aims to improve patients' functional capacity before surgery to reduce perioperative complications, promote recovery and decrease probability of disability. The planned economic evaluation is performed alongside a large German multi-centre pragmatic, two-arm parallel-group, randomized controlled trial on prehabilitation for frail elderly patients before elective surgery compared to standard care (PRAEP-GO RCT). The aim is to determine the cost-effectiveness and cost-utility of prehabilitation for frail elderly before an elective surgery.

METHODS

The planned health economic evaluation comprises cost-effectiveness, and cost-utility analyses. Analyses are conducted in the German context from different perspectives including the payer perspective, i.e. the statutory health insurance, the societal perspective and the health care provider perspective. Data on outcomes and costs, are collected alongside the ongoing PRAEP-GO RCT. The trial population includes frail or pre-frail patients aged ≥70 years with planned elective surgery. The intervention consists of frailty screening (Fried phenotype), a shared decision-making conference determining modality (physiotherapy and unsupervised physical exercises, nutrition counselling, etc.) and setting (inpatient, day care, outpatient etc.) of a 3-week individual multimodal prehabilitation prior to surgery. The control group receives standard preoperative care. Costs include the intervention costs, the costs of the index hospital stay for surgery, and health care resources consumed during a 12-month follow-up. Clinical effectiveness outcomes included in the economic evaluation are the level of care dependency, the degree of disability as measured by the WHO Disability Assessment Schedule 2.0 (WHODAS 2.0), quality-adjusted life years (QALY) derived from the EQ-5D-5L and the German utility set, and complications occurring during the index hospital stay. Each adopted perspective considers different types of costs and outcomes as outlined in the protocol. All analyses will feature Intention-To-Treat analysis. To explore methodological and parametric uncertainties, we will conduct probabilistic and deterministic sensitivity analyses. Subgroup analyses will be performed as secondary analyses.

DISCUSSION

The health economic evaluation will provide insights into the cost-effectiveness of prehabilitation in older frail populations, informing decision-making processes and contributing to the evidence base in this field. Potential limitation includes a highly heterogeneous trial population.

TRIAL REGISTRATION

PRAEP-GO RCT: NCT04418271; economic evaluation: OSF ( https://osf.io/ecm74 ).

Differential Treatment Effects of Subgroup Analyses in Phase 3 Oncology Trials From 2004 to 2020

Importance

Subgroup analyses are often performed in oncology to investigate differential treatment effects and may even constitute the basis for regulatory approvals. Current understanding of the features, results, and quality of subgroup analyses is limited.

Objective

To evaluate forest plot interpretability and credibility of differential treatment effect claims among oncology trials.

Design, Setting, and Participants

This cross-sectional study included randomized phase 3 clinical oncology trials published prior to 2021. Trials were screened from ClinicalTrials.gov.

Main Outcomes and Measures

Missing visual elements in forest plots were defined as a missing point estimate or use of a linear x-axis scale for hazard and odds ratios. Multiplicity of testing control was recorded. Differential treatment effect claims were rated using the Instrument for Assessing the Credibility of Effect Modification Analyses. Linear and logistic regressions evaluated associations with outcomes.

Results

Among 785 trials, 379 studies (48%) enrolling 331 653 patients reported a subgroup analysis. The forest plots of 43% of trials (156 of 363) were missing visual elements impeding interpretability. While 4148 subgroup effects were evaluated, only 1 trial (0.3%) controlled for multiple testing. On average, trials that did not meet the primary end point conducted 2 more subgroup effect tests compared with trials meeting the primary end point (95% CI, 0.59-3.43 tests; P = .006). A total of 101 differential treatment effects were claimed across 15% of trials (55 of 379). Interaction testing was missing in 53% of trials (29 of 55) claiming differential treatment effects. Trials not meeting the primary end point were associated with greater odds of no interaction testing (odds ratio, 4.47; 95% CI, 1.42-15.55, P = .01). The credibility of differential treatment effect claims was rated as low or very low in 93% of cases (94 of 101).

Conclusions and Relevance

In this cross-sectional study of phase 3 oncology trials, nearly half of trials presented a subgroup analysis in their primary publication. However, forest plots of these subgroup analyses largely lacked essential features for interpretation, and most differential treatment effect claims were not supported. Oncology subgroup analyses should be interpreted with caution, and improvements to the quality of subgroup analyses are needed.

Evaluation of intensive community care services for young people with psychiatric emergencies: study protocol for a multi-centre parallel-group, single-blinded randomized controlled trial with an internal pilot phase

BACKGROUND

Over 3000 young people under the age of 18 are admitted to Tier 4 Child and Adolescent Mental Health Services (CAMHS) inpatient units across the UK each year. The average length of hospital stay for young people across all psychiatric units in the UK is 120 days. Research is needed to identify the most effective and efficient ways to care for young people (YP) with psychiatric emergencies. This study aims to evaluate the clinical effectiveness and cost-effectiveness of intensive community care service (ICCS) compared to treatment as usual (TAU) for young people with psychiatric emergencies.

METHODS

This is a multicentre two-arm randomized controlled trial (RCT) with an internal pilot phase. Young people aged 12 to < 18 considered for admission at participating NHS organizations across the UK will be randomized 1:1 to either TAU or ICCS. The primary outcome is the time to return to or start education, employment, or training (EET) at 6 months post-randomization. Secondary outcomes will include evaluations of mental health and overall well-being and patient satisfaction. Service use and costs and cost-effectiveness will also be explored. Intention-to-treat analysis will be adopted. The trial is expected to be completed within 42 months, with an internal pilot phase in the first 12 months to assess the recruitment feasibility. A process evaluation using visual semi-structured interviews will be conducted with 42 young people and 42 healthcare workers.

DISCUSSION

This trial is the first well-powered randomized controlled trial evaluating the clinical and cost-effectiveness of ICCS compared to TAU for young people with psychiatric emergencies in Great Britain.

TRIAL REGISTRATION

ISRCTN ISRCTN42999542, Registration on April 29, 2020.

CLEAR - clozapine in early psychosis: study protocol for a multi-centre, randomised controlled trial of clozapine vs other antipsychotics for young people with treatment resistant schizophrenia in real world settings

BACKGROUND

Clozapine is an antipsychotic drug with unique efficacy, and it is the only recommended treatment for treatment-resistant schizophrenia (TRS: failure to respond to at least two different antipsychotics). However, clozapine is also associated with a range of adverse effects which restrict its use, including blood dyscrasias, for which haematological monitoring is required. As treatment resistance is recognised earlier in the illness, the question of whether clozapine should be prescribed in children and young people is increasingly important. However, most research to date has been in older, chronic patients, and evidence regarding the efficacy and safety of clozapine in people under age 25 is lacking. The CLEAR (CLozapine in EARly psychosis) trial will assess whether clozapine is more effective than treatment as usual (TAU), at the level of clinical symptoms, patient rated outcomes, quality of life and cost-effectiveness in people below 25 years of age. Additionally, a nested biomarker study will investigate the mechanisms of action of clozapine compared to TAU.

METHODS AND DESIGN

This is the protocol of a multi-centre, open label, blind-rated, randomised controlled effectiveness trial of clozapine vs TAU (any other oral antipsychotic monotherapy licenced in the British National Formulary) for 12 weeks in 260 children and young people with TRS (12-24 years old).

AIM AND OBJECTIVES

The primary outcome is the change in blind-rated Positive and Negative Syndrome Scale scores at 12 weeks from baseline. Secondary outcomes include blind-rated Clinical Global Impression, patient-rated outcomes, quality of life, adverse effects, and treatment adherence. Patients will be followed up for 12 months and will be invited to give consent for longer term follow-up using clinical records and potential re-contact for further research. For mechanism of action, change in brain magnetic resonance imaging (MRI) biomarkers and peripheral inflammatory markers will be measured over 12 weeks.

DISCUSSION

The CLEAR trial will contribute knowledge on clozapine effectiveness, safety and cost-effectiveness compared to standard antipsychotics in young people with TRS, and the results may guide future clinical treatment recommendation for early psychosis.

TRIAL REGISTRATION

ISRCTN Number: 37176025, IRAS Number: 1004947.

TRIAL STATUS

In set-up. Protocol version 4.0 01/08/23. Current up to date protocol available here: https://fundingawards.nihr.ac.uk/award/NIHR131175# /.

Relative Efficacy of an Acceptance and Commitment Therapy-Based Smartphone App with a Standard US Clinical Practice Guidelines-Based App for Smoking Cessation in Dual Users of Combustible and Electronic Cigarettes: Secondary Findings from a Randomized Trial

BACKGROUND

While smartphone apps for smoking cessation have shown promise for combustible cigarette smoking cessation, their efficacy in helping dual users of combustible and electronic cigarettes (e-cigarettes) to quit cigarettes remains unknown. This study utilized data from a randomized trial to determine if an Acceptance and Commitment Therapy (ACT)-based app (iCanQuit) was more efficacious than a US Clinical Practice Guidelines-based app (QuitGuide) for combustible cigarette smoking cessation among 575 dual users.

METHODS

The primary cessation outcome was self-reported, complete-case 30-day abstinence from combustible cigarettes at 12 months. Logistic regression assessed the interaction between dual use and treatment arm on the primary outcome in the full trial sample (N = 2,415). We then compared the primary outcome between arms among dual users (iCanQuit: n = 297; QuitGuide: n = 178). Mediation analyses were conducted to explore mechanisms of action of the intervention: acceptance of cues to smoke and app engagement. Results: There was an interaction between dual use of combustible and e-cigarettes and treatment arm on the primary outcome (p = 0.001). Among dual users, 12-month abstinence from cigarettes did not differ between arms (23% for iCanQuit vs. 27% for QuitGuide, p = 0.40). Mediation analysis revealed a significant positive indirect effect of the iCanQuit app on 12-month abstinence from cigarettes through acceptance of emotions that cue smoking (p = 0.004).

CONCLUSIONS

Findings from this study of dual users of combustible and e-cigarettes showed no evidence of a difference in quit rates between arms. Acceptance of emotions that cue smoking is a potential mechanism contributing to cigarette smoking abstinence among dual users.

Systematic literature review of traits and outcomes reported in randomised controlled trials of asthma with regular dosing of inhaled corticosteroids with short-acting β2-agonist reliever, as-needed ICS/formoterol, or ICS/formoterol maintenance and reliever therapy

INTRODUCTION

Asthma treatments based solely on diagnostic label do not benefit patients equally. To identify patient traits that may be associated with improved treatment response to regular inhaled corticosteroid (ICSs) dosing with short-acting β2-agonist reliever or ICS/formoterol-containing therapy, a systematic literature review (SLR) was conducted.

METHODS

Searches of databases including MEDLINE and Embase identified randomised controlled trials (RCTs) of patients with asthma, aged ≥12 years, published 1998-2022, containing ≥1 regular ICS dosing or ICS/formoterol-containing treatment arm, and reporting patient traits and outcomes of interest. Relevant data was extracted and underwent a feasibility assessment to determine suitability for meta-analysis.

RESULTS

The SLR identified 39 RCTs of 72,740 patients and 90 treatment arms, reporting 11 traits and 11 outcomes. Five patient traits (age, body mass index, FEV1, smoking history, asthma control) and five outcomes (exacerbation rate, lung function, asthma control, adherence, time to first exacerbation) were deemed feasible for inclusion in meta-analyses due to sufficient comparable reporting. Subgroups of clinical outcomes stratified by levels of patient traits were reported in 16 RCTs.

CONCLUSION

A systematic review of studies of regular ICS dosing with SABA or ICS/formoterol-containing treatment strategies in asthma identified consistent reporting of five traits and outcomes, allowing exploration of associations with treatment response. Conversely, many other traits and outcomes, although being potentially relevant, were inconsistently reported and limited subgroup reporting meant analyses of treatment response for subgroups of traits was not possible. We recommend more consistent measurement and reporting of clinically relevant patient traits and outcomes in respiratory RCTs.

Quantifying and reducing inequity in average treatment effect estimation

BACKGROUND

Across studies of average treatment effects, some population subgroups consistently have lower representation than others which can lead to discrepancies in how well results generalize.

METHODS

We develop a framework for quantifying inequity due to systemic disparities in sample representation and a method for mitigation during data analysis. Assuming subgroup treatment effects are exchangeable, an unbiased sample average treatment effect estimator will have lower mean-squared error, on average across studies, for subgroups with less representation when treatment effects vary. We present a method for estimating average treatment effects in representation-adjusted samples which enables subgroups to optimally leverage information from the full sample rather than only their own subgroup's data. Two approaches for specifying representation adjustment are offered-one minimizes average mean-squared error for each subgroup separately and the other balances minimization of mean-squared error and equal representation. We conduct simulation studies to compare the performance of the proposed estimators to several subgroup-specific estimators.

RESULTS

We find that the proposed estimators generally provide lower mean squared error, particularly for smaller subgroups, relative to the other estimators. As a case study, we apply this method to a subgroup analysis from a published study.

CONCLUSIONS

We recommend the use of the proposed estimators to mitigate the impact of disparities in representation, though structural change is ultimately needed.

Efficacy of Web-Delivered Acceptance and Commitment Therapy (ACT) for Helping Black Adults Quit Smoking

BACKGROUND

Digital smoking cessation interventions may reduce racial disparities in cessation because they are low cost, scalable, and can provide support at any place or time. Despite their promise, whether Black adults engage with and benefit from these tools is largely unknown. In a secondary analysis of a randomized trial, we explored the efficacy of an acceptance and commitment therapy (ACT)-based website (WebQuit) for smoking cessation compared to a US clinical practice guidelines-based website (Smokefree.gov) among Black adults.

METHODS

A total of 316 Black adult smokers were enrolled in the trial between May 2017 and September 2018 and received access to WebQuit or Smokefree for 12 months. Participants self-reported on 30-day and 7-day abstinence from cigarette smoking at 3, 6, and 12-months. Treatment engagement was objectively measured and compared between arms. Participants also reported on their willingness to accept cues to smoke without smoking.

RESULTS

WebQuit versus Smokefree participants engaged more with their website (higher number of logins, Incidence Rate Ratio (IRR) = 2.21; 95% CI: 1.70, 2.89). Complete-case 30-day point prevalence abstinence (PPA) at 12-months was 34% for WebQuit vs. 29% for Smokefree (OR = 1.22 95% CI: 0.73, 2.04). Increases in participants' willingness to accept cues to smoke mediated the intervention effect on abstinence from cigarette smoking at 12 months.

CONCLUSIONS

This study addressed the lack of research on the utilization and efficacy of digital interventions for helping Black adults quit smoking. WebQuit participants engaged more with their website and quit smoking at a somewhat higher rate relative to Smokefree participants, albeit nonsignificant. Findings suggest high acceptability of ACT-based digital interventions to enable Black adult smokers to engage and sustain behavior changes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01812278.

Use of e-Cigarettes in Cigarette Smoking Cessation: Secondary Analysis of a Randomized Controlled Trial

BACKGROUND

Many adults use e-cigarettes to help them quit cigarette smoking. However, the impact of self-selected use of e-cigarettes on cigarette smoking cessation, particularly when concurrently receiving app-based behavioral interventions, remains unexplored.

OBJECTIVE

This study used data from a randomized trial of 2 smartphone apps to compare 12-month cigarette smoking cessation rates between participants who used e-cigarettes on their own (ie, adopters: n=465) versus those who did not (ie, nonadopters: n=1097).

METHODS

The study population included all participants who did not use e-cigarettes at baseline. "Adopters" were those who self-reported the use of e-cigarettes at either 3- or 6-month follow-ups. "Nonadopters" were those who self-reported no use of e-cigarettes at either follow-up time point. The primary cessation outcome was self-reported, complete-case, 30-day point prevalence abstinence from cigarette smoking at 12 months. Secondary outcomes were missing-as-smoking and multiple imputation analyses of the primary outcome, prolonged abstinence, and cessation of all nicotine and tobacco products at 12 months. In logistic regression models, we first examined the potential interaction between e-cigarette use and treatment arm (iCanQuit vs QuitGuide) on the primary cessation outcome. Subsequently, we compared 12-month cigarette smoking cessation rates between adopters and nonadopters separately for each app.

RESULTS

There was suggestive evidence for an interaction between e-cigarette use and treatment arm on cessation (P=.05). In the iCanQuit arm, 12-month cigarette smoking cessation rates were significantly lower among e-cigarette adopters compared with nonadopters (41/193, 21.2% vs 184/527, 34.9%; P=.003; odds ratio 0.55, 95% CI 0.37-0.81). In contrast, in the QuitGuide arm, 12-month cigarette smoking cessation rates did not differ between adopters and nonadopters (46/246, 18.7% vs 104/522, 19.9%; P=.64; odds ratio 0.91, 95% CI 0.62-1.35).

CONCLUSIONS

The use of e-cigarettes while concurrently receiving an app-based smoking cessation intervention was associated with either a lower or an unimproved likelihood of quitting cigarette smoking compared to no use. Future behavioral treatments for cigarette smoking cessation should consider including information on the potential consequences of e-cigarette use.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02724462; https://clinicaltrials.gov/study/NCT02724462.

High-Frequency Ipsilesional versus Low-Frequency Contralesional Transcranial Magnetic Stimulation after Stroke: Differential Effects on Ipsilesional Upper Extremity Motor Recovery

Background and Objectives: Stroke is a major cause of death and disability worldwide; therefore, transcranial magnetic stimulation (TMS) is being widely studied and clinically applied to improve motor deficits in the affected arm. However, recent studies indicate that the function of both arms can be affected after stroke. It currently remains unknown how various TMS methods affect the function of the ipsilesional upper extremity. Materials and Methods: Thirty-five subacute stroke patients with upper extremity motor deficits were enrolled in this study and randomly allocated into three groups, receiving either (1) low-frequency rTMS over the contralesional hemisphere; (2) high-frequency rTMS over the ipsilesional hemisphere; or (3) no stimulation. Experimental groups received 10 rTMS sessions over two weeks alongside standard rehabilitation, and the control group received the same procedures except for rTMS. Both affected and unaffected upper extremity motor function was evaluated using hand grip strength and Functional Independence Measure (FIM) tests before and after rehabilitation (7 weeks apart). Results: All groups showed significant improvement in both the affected and unaffected hand grip and FIM scores (p < 0.05). HF-rTMS led to a notably higher increase in unaffected hand grip strength than the control group (p = 0.007). There was no difference in the improvement in affected upper extremity motor function between the groups. The FIM score increase was lower in the control group compared to experimental groups, although not statistically significant. Conclusions: This study demonstrates the positive effect of ipsilesional HF-rTMS on the improvement in unaffected arm motor function and reveals the positive effect of both LF- and HF-rTMS on the affected upper extremity motor function recovery.

Prevalence and implications of significance testing for baseline covariate imbalance in randomised cancer clinical trials: The Table 1 Fallacy

BACKGROUND

The 'Table 1 Fallacy' refers to the unsound use of significance testing for comparing the distributions of baseline variables between randomised groups to draw erroneous conclusions about balance or imbalance. We performed a cross-sectional study of the Table 1 Fallacy in phase III oncology trials.

METHODS

From ClinicalTrials.gov, 1877 randomised trials were screened. Multivariable logistic regressions evaluated predictors of the Table 1 Fallacy.

RESULTS

A total of 765 randomised controlled trials involving 553,405 patients were analysed. The Table 1 Fallacy was observed in 25% of trials (188 of 765), with 3% of comparisons deemed significant (59 of 2353), approximating the typical 5% type I error assertion probability. Application of trial-level multiplicity corrections reduced the rate of significant findings to 0.3% (six of 2345 tests). Factors associated with lower odds of the Table 1 Fallacy included industry sponsorship (adjusted odds ratio [aOR] 0.29, 95% confidence interval [CI] 0.18-0.47; multiplicity-corrected P < 0.0001), larger trial size (≥795 versus <280 patients; aOR 0.32, 95% CI 0.19-0.53; multiplicity-corrected P = 0.0008), and publication in a European versus American journal (aOR 0.06, 95% CI 0.03-0.13; multiplicity-corrected P < 0.0001).

CONCLUSIONS

This study highlights the persistence of the Table 1 Fallacy in contemporary oncology randomised controlled trials, with one of every four trials testing for baseline differences after randomisation. Significance testing is a suboptimal method for identifying unsound randomisation procedures and may encourage misleading inferences. Journal-level enforcement is a possible strategy to help mitigate this fallacy.

Does information on age-related fertility decline and fertility policies affect university students' family and career expectations? Evidence from a randomized controlled trial

BACKGROUND

Past research shows that young adults have poor knowledge of age-related fertility decline and that the provision of information can improve fertility knowledge. We provide university students with information on age-related fertility and fertility-related policies and investigate whether the provision of such information affects their family formation and career expectations.

METHODS

A three-armed randomized controlled trial was conducted online in Singapore between September and October 2021. A total of 1000 undergraduate students were recruited through campus advertisements to complete a 30- to 45-minute online survey, which randomly exposed participants to one of three informational brochures on age-related fertility decline, fertility policies, or diabetes (control group). Participants answered questions on family formation and career expectations both before and after the information intervention. Analysis of covariance was used to assess the effects of the information intervention.

RESULTS

Exposure to age-related fertility information resulted in significant reductions in the ideal age at first childbirth, significant increases in the expected probability of marriage before age 30, and (among female participants) significant increases in the expected likelihood of undergoing social egg-freezing. No difference existed in child-number ideals, educational aspirations, and income expectations between groups after exposure. No difference existed between the fertility policy information group and the control group after exposure in any of the outcomes of interest.

CONCLUSIONS

Information on age-related fertility decline brought forward university students' expected timing of childbearing and marriage without reducing their educational and career expectations. The provision of fertility information at early ages, such as during university, can help correct widespread inaccurate beliefs about fertility and promote realistic family formation planning without adversely affecting educational and career goals.

TRIAL REGISTRATION

ClinicalTrials.gov.

Characteristics of post hoc subgroup analyses of oncology clinical trials: a systematic review

BACKGROUND

Subgroup analyses in clinical trials assess intervention effects on specific patient subgroups, ensuring generalizability. However, they are usually only able to generate hypotheses rather than definitive conclusions. This study examined the prevalence and characteristics of post hoc subgroup analysis in oncology.

METHODS

We systematically reviewed published subgroup analyses from 2000 to 2022. We included articles presenting secondary, post hoc, or subgroup analyses of interventional clinical trials in oncology, cancer survivorship, or cancer screening, published separately from the original clinical trial publication. We collected cancer type, year of publication, where and how subgroup analyses were reported, and funding.

RESULTS

Out of 16 487 screened publications, 1612 studies were included, primarily subgroup analyses of treatment trials for solid tumors (82%). Medical writers contributed to 31% of articles, and 58% of articles reported conflicts of interest. Subgroup analyses increased significantly over time, with 695 published between 2019 and 2022, compared to 384 from 2000 to 2014. Gastrointestinal tumors (25%) and lymphoid lineage tumors (39%) were the most frequently studied solid and hematological malignancies, respectively. Industry funding and reporting of conflicts of interest increased over time. Subgroup analyses often neglected to indicate their secondary nature in the title. Most authors were from high-income countries, most commonly North America (45%).

CONCLUSIONS

This study demonstrates the rapidly growing use of post hoc subgroup analysis of oncology clinical trials, revealing that the majority are supported by pharmaceutical companies, and they frequently fail to indicate their secondary nature in the title. Given the known methodological limitations of subgroup analyses, caution is recommended among authors, readers, and reviewers when conducting and interpreting these studies.

Exploring treatment effect heterogeneity of a PROMs alert intervention in knee and hip arthroplasty patients: A causal forest application

Patient reported outcome measures (PROMs) experience an uptake in use for hip (HA) and knee arthroplasty (KA) patients. As they may be used for patient monitoring interventions, it remains unclear whether their use in HA/KA patients is effective, and which patient groups benefit the most. Nonetheless, knowledge about treatment effect heterogeneity is crucial for decision makers to target interventions towards specific subgroups that benefit to a greater extend. Therefore, we evaluate the treatment effect heterogeneity of a remote PROM monitoring intervention that includes ∼8000 HA/KA patients from a randomized controlled trial conducted in nine German hospitals. The study setting gave us the unique opportunity to apply a causal forest, a recently developed machine learning method, to explore treatment effect heterogeneity of the intervention. We found that among both HA and KA patients, the intervention was especially effective for patients that were female, >65 years of age, had a blood pressure disease, were not working, reported no backpain and were adherent. When transferring the study design into standard care, policy makers should make use of the knowledge obtained in this study and allocate the treatment towards subgroups for which the treatment is especially effective.

Change-plane analysis for subgroup detection with a continuous treatment

Detecting and characterizing subgroups with differential effects of a binary treatment has been widely studied and led to improvements in patient outcomes and population risk management. Under the setting of a continuous treatment, however, such investigations remain scarce. We propose a semiparametric change-plane model and consequently a doubly robust test statistic for assessing the existence of two subgroups with differential treatment effects under a continuous treatment. The proposed testing procedure is valid when either the baseline function for the covariate effects or the generalized propensity score function for the continuous treatment is correctly specified. The asymptotic distributions of the test statistic under the null and local alternative hypotheses are established. When the null hypothesis of no subgroup is rejected, the change-plane parameters that define the subgroups can be estimated. This paper provides a unified framework of the change-plane method to handle various types of outcomes, including the exponential family of distributions and time-to-event outcomes. Additional extensions with nonparametric estimation approaches are also provided. We evaluate the performance of our proposed methods through extensive simulation studies under various scenarios. An application to the Health Effects of Arsenic Longitudinal Study with a continuous environmental exposure of arsenic is presented.

Deficits in consummatory reward relate to severity of cocaine use

BACKGROUND AND AIMS

Identifying modifiable neuropsychological factors associated with more severe CUD could improve CUD treatment. Impairments in processing of non-drug rewards may be one such factor. This study assessed the relationship between reward functioning and cocaine use severity using multi-modal measures of three distinct reward functions: consummatory reward (pleasure or "liking"); motivational reward ("wanting") and reward learning.

METHODS

Fifty-three adults with at least moderate CUD completed self-report and behavioral measures of consummatory reward, motivational reward and reward learning, and a composite cocaine use severity measure including quantity, frequency and life impacts of cocaine use. We conducted parallel Frequentist and Bayesian multiple regressions with measures of reward functioning as predictors of cocaine use severity.

RESULTS

Less self-reported ability to experience pleasure, a hypothesized measure of consummatory reward, significantly predicted greater severity after adjustment for covariates and multiple hypothesis testing, β = 0.39, t(38) = 2.86, p = 0.007. Bayesian analyses confirmed a highly likely association between severity and ability to experience pleasure, and provided moderate evidence for associations with willingness to exert effort and reward learning.

CONCLUSIONS

Our results suggest that less experience of subjective pleasure is related to greater cocaine use severity. This cross-sectional study cannot establish whether differences in consummatory reward are pre-existing, a result of CUD, or both. However, these results suggest interventions focused on increasing subjective pleasure, such as mindful "savoring", should be investigated for CUD.

Abdominal massage and laxative use for constipation: a pilot study

BACKGROUND

Constipation is a very frequent condition. Pharmacological treatment leads to the onset of complications in the long term.

AIM

To study the effects of abdominal massage and bowel training combined with polyethene glycol compared with laxative alone. Researchers studied the frequency of evacuations, use of laxatives, appetite, and food intake of older persons. In addition, feasibility in the daily routine of nursing care was studied.

METHODS

A pilot, randomised controlled trial was conducted. Older people living in a facility for self-sufficient residents were enrolled and randomised to the intervention or control group. The massage was administered for 4 weeks. The stool type according to the Bristol Stool Form Scale and secondary outcomes were collected at baseline, before any massage session and at the end of the intervention.

FINDINGS

32 participants were enrolled. Significant improvements were found in the number of evacuations, need for enemas, Bristol scores, appetite and food intake.

CONCLUSION

Significant improvements were found in all major outcomes.

Evaluation of randomised controlled trials published in Indian specialty dental journals for statistical testing of baseline differences: A meta-epidemiological study

Background

In randomised controlled trials (RCTs), the application of a test of significance to compare the baseline differences between the intervention groups is a common practice, though it has been condemned by many researchers.

Objective

This study aimed to assess the proportion of RCTs on human participants comparing the baseline differences between intervention groups using the test of significance in nine dental specialty journals published in India and to estimate the proportion of studies reporting baseline demographic and clinical characteristics in a table.

Materials and Methods

RCTs published in nine dental journals published by dental specialty associations of India were screened. A literature search was limited to the time duration of five years from 2017 to 2021.

Results

The authors analysed 326 RCTs. Of 326 RCTs published, 237 RCTs (72.7%) did not report the baseline demographic and clinical characteristics table. Tests of significance were applied to compare baseline differences between the intervention arms in 148 (45.4%) RCTs published.

Conclusions

Although criticised by the Consolidated Standards of Reporting Trials (CONSORT) statement, the majority of the trials published in dental specialty journals failed to avoid comparison of baseline differences with significance test and failed to report baseline characteristic table.

Single-group studies in leading physical therapy journals commonly make inappropriate conclusions regarding treatment effect modifiers. A systematic review

BACKGROUND

Characteristics that identify patients who respond differently to certain interventions are called treatment effect modifiers. Some studies inappropriately report the presence of treatment effect modifiers without adequate study designs.

OBJECTIVES

To evaluate what proportion of single-group studies published in leading physical therapy journals inappropriately report treatment effect modifiers, and to assess whether the proportion varies over time or between journals.

METHODS

A systematic review was conducted of studies published in eight leading physical therapy journals since 2000. Eligible studies were single-group studies (e.g., cohort study or secondary analysis of treatment arm of randomised controlled trial) that investigated any condition, treatment or outcome. Studies that suggested participants with certain baseline characteristics responded better/or worse to the treatment, were considered to have reported inappropriately. Studies reporting that participants with certain baseline characteristics had improved outcomes but did not state it was due to the treatment were considered to have reported appropriately. The proportion of inappropriate reporting was compared over time and between journals.

RESULTS

Of the 145 included studies, 73 (50.3%) were categorised as inappropriately reporting treatment effect modifiers. The proportion of inappropriate reporting was highest in the most recent period, 2018 - 2022 (59.6%) and 2006 - 2011 (55.6%). The proportion of inappropriate reporting varied substantially between journals from 0% (Journal of Physiotherapy) to 91.7% (Journal of Neurologic Physical Therapy).

CONCLUSIONS

A large proportion (50.3%) of single-arm studies in leading physical therapy journals inappropriately report treatment effect modifiers. This inappropriate reporting risks misleading clinicians when selecting interventions for individual patients.

Preventive interventions in individuals at risk for Rheumatoid Arthritis: State of the art and perspectives

During the last decade, the outlook for patients with rheumatoid arthritis (RA) has improved greatly, especially for patients with autoantibody-positive RA. To further improve long-term disease outcomes, the field has turned to investigating the efficacy of treatment initiated in the pre-arthritic phase of RA, based on the adage "the sooner the better." In this review, the concept of prevention is evaluated and different risk stages are being examined for their pre-test risks of RA development. These risks affect the post-test risk of biomarkers used at these stages and, consequently, the accuracy with which the risk of RA can be estimated. Furthermore, through their effect on accurate risk stratification, these pre-test risks ultimately also associate with the likelihood of false-negative trial results (the so-called "clinicostatistical tragedy"). Outcome measures to assess preventive effects are evaluated and relate to either the occurrence of disease itself or to the severity of risk factors for RA development. Results of recently completed prevention studies are discussed in the light of these theoretical considerations. The results vary, but clear prevention of RA has not been demonstrated. While some treatments (e.g. methotrexate) persistently reduced symptom severity, physical disability, and the severity of imaging joint inflammation, other treatments were not reported to produce long-lasting effects (hydroxychloroquine, rituximab, atorvastatin). The review concludes with future perspectives regarding the design of new prevention studies and considerations and requirements before findings can be implemented in daily practice in individuals at risk of RA attending rheumatology practices.

Allocation concealment appraisal of clinical therapy trials using the extended Composite Quality Score (CQS-2)-An empirically based update

Objectives

The objective of this study was to revise CQS-2/Criterion II concerning allocation concealment appraisal for prospective, controlled clinical therapy trials.

Methods

Meta-analyses of trials with inadequate allocation concealment were tested for in-between trial heterogeneity (I2 > 0) due to imbalances in baseline variables. Meta-analyses with positive test results were used as a basis to deduce criteria for adequate allocation concealment. The CQS-2/Criterion II was reformulated in line with the findings.

Result

One suitable meta-analysis was identified. Two forest plots with data from five and four trials with inadequate/unclear allocation concealment were selected for testing. In addition, a total of five trials with adequate allocation concealment were identified. The meta-analysis test results were positive, and keywords for the judgment of adequate allocation concealment were extracted verbatim from the text of the meta-analysis. The extracted keywords indicated "central allocation" as the main criterion for adequate allocation concealment. Criterion II of the CQS-2 was revised accordingly.

Conclusion

Criterion II of the CQS-2 trial appraisal tool was revised. The revised appraisal tool was specified as version CQS-2B.

Methylprednisolone in acute traumatic spinal cord injury: case-matched outcomes from the NASCIS2 and Sygen historical spinal cord injury studies with contemporary statistical analysis

OBJECTIVE

Methylprednisolone (MP) to treat acute traumatic spinal cord injury (ATSCI) remains controversial since the release of the second National Acute Spinal Cord Injury Study (NASCIS2) in 1990. As two historical studies, NASCIS2 and Sygen in ATSCI, used identical MP dosages, it was possible to construct a new case-level pooled ATSCI data set satisfying contemporary criteria and able to clarify the effect of MP.

METHODS

The new pooled data set was first modernized by excluding patients with injury levels caudal to T10, lower-extremity American Spinal Injury Association (ASIA) motor scores (LEMSs) ≥ 46, Glasgow Coma Scale scores ≤ 11, and age < 15 or > 75 years, and then standardized to the ASIA grading and scoring format. A new updated NASCIS2 data set from this pooled data set contained 31.6% fewer patients than the 1990 NASCIS2 data set.

RESULTS

In the new pooled data set, recovery of LEMSs from baseline to 26 weeks, the primary outcome variable, was separated statistically into five different injury severity cohorts (p < 0.0001). The severity cohorts contained groups with severe floor (62.9%) and ceiling (10.7%) effects, which do not contribute to drug effects. The new NASCIS2 data set duplicated the p value for MP versus placebo in the sub-subgroup analysis of MP initiated ≤ 8 hours (the subgroup) and recovery of motor function on only the right side of the body (a further subgroup within the ≤ 8-hour subgroup), presented as the positive MP effect in the original NASCIS2 reporting. However, current statistical interpretation considers results seen only in post hoc sub-subgroups, without multi-test corrections, to be random effects without clinical significance. The combined case-level pooled data set from the NASCIS2 and Sygen studies increased the MP group from 106 to 431 patients, creating a new MP combined group. This new data set served as a surrogate for a contemporary MP study and found that administration of MP did not enhance ASIA motor score improvement in the lower extremities at 26 weeks. Secondary analysis of descending ASIA motor and sensory cervical neurological levels in cervical ATSCI patients at 26 weeks also found no MP drug effect.

CONCLUSIONS

Analysis of both the new updated NASCIS2 data set and the new case-matched pooled data set from two historical ATSCI studies revealed that administration of MP after spinal cord injury did not demonstrate any enhancement in neurological recovery at 26 weeks. The results of this analysis warrant review by clinical guideline groups.

Heterogeneous Treatment Effects of Therapeutic-Dose Heparin in Patients Hospitalized for COVID-19

IMPORTANCE

Randomized clinical trials (RCTs) of therapeutic-dose heparin in patients hospitalized with COVID-19 produced conflicting results, possibly due to heterogeneity of treatment effect (HTE) across individuals. Better understanding of HTE could facilitate individualized clinical decision-making.

OBJECTIVE

To evaluate HTE of therapeutic-dose heparin for patients hospitalized for COVID-19 and to compare approaches to assessing HTE.

DESIGN, SETTING, AND PARTICIPANTS

Exploratory analysis of a multiplatform adaptive RCT of therapeutic-dose heparin vs usual care pharmacologic thromboprophylaxis in 3320 patients hospitalized for COVID-19 enrolled in North America, South America, Europe, Asia, and Australia between April 2020 and January 2021. Heterogeneity of treatment effect was assessed 3 ways: using (1) conventional subgroup analyses of baseline characteristics, (2) a multivariable outcome prediction model (risk-based approach), and (3) a multivariable causal forest model (effect-based approach). Analyses primarily used bayesian statistics, consistent with the original trial.

EXPOSURES

Participants were randomized to therapeutic-dose heparin or usual care pharmacologic thromboprophylaxis.

MAIN OUTCOMES AND MEASURES

Organ support-free days, assigning a value of -1 to those who died in the hospital and the number of days free of cardiovascular or respiratory organ support up to day 21 for those who survived to hospital discharge; and hospital survival.

RESULTS

Baseline demographic characteristics were similar between patients randomized to therapeutic-dose heparin or usual care (median age, 60 years; 38% female; 32% known non-White race; 45% Hispanic). In the overall multiplatform RCT population, therapeutic-dose heparin was not associated with an increase in organ support-free days (median value for the posterior distribution of the OR, 1.05; 95% credible interval, 0.91-1.22). In conventional subgroup analyses, the effect of therapeutic-dose heparin on organ support-free days differed between patients requiring organ support at baseline or not (median OR, 0.85 vs 1.30; posterior probability of difference in OR, 99.8%), between females and males (median OR, 0.87 vs 1.16; posterior probability of difference in OR, 96.4%), and between patients with lower body mass index (BMI <30) vs higher BMI groups (BMI ≥30; posterior probability of difference in ORs >90% for all comparisons). In risk-based analysis, patients at lowest risk of poor outcome had the highest propensity for benefit from heparin (lowest risk decile: posterior probability of OR >1, 92%) while those at highest risk were most likely to be harmed (highest risk decile: posterior probability of OR <1, 87%). In effect-based analysis, a subset of patients identified at high risk of harm (P = .05 for difference in treatment effect) tended to have high BMI and were more likely to require organ support at baseline.

CONCLUSIONS AND RELEVANCE

Among patients hospitalized for COVID-19, the effect of therapeutic-dose heparin was heterogeneous. In all 3 approaches to assessing HTE, heparin was more likely to be beneficial in those who were less severely ill at presentation or had lower BMI and more likely to be harmful in sicker patients and those with higher BMI. The findings illustrate the importance of considering HTE in the design and analysis of RCTs.

TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT02735707, NCT04505774, NCT04359277, NCT04372589.

No long-term effects after a 3-week open-label placebo treatment for chronic low back pain: a 3-year follow-up of a randomized controlled trial

ABSTRACT

Chronic low back pain is prevalent, highly disabling, and a relevant socioeconomic health concern. Although allocated to placebo groups, patients in randomized controlled trials show significant pain relief, pointing to the relevance of placebo effects. Overcoming ethical and legal concerns related to deceptive placebos, recent studies have demonstrated the efficacy of short-term treatments for chronic low back pain with open-label (ie, nondeceptive) placebos. However, data on long-term efficacy of open-label placebos are sparse. Here, we report a 3-year follow-up of our previously published randomized controlled trial demonstrating pain reduction, improvement in disability, and depressive symptoms after a 3-week treatment with open-label placebos. Including records from 89 previously enrolled patients, we investigated changes between the groups with and without previous open-label placebo treatment in pain intensity (primary outcome), disability and mood (secondary outcomes), biopsychosocial factors and lifestyle (exploratory outcomes) from parent baseline to follow-up. Over the 3-year period, there were no differences in any outcome between groups with and without open-label placebo treatment. Therefore, our follow-up data do not support the previously suggested assumption that a 3-week open-label placebo treatment has long-term effects. This study was preregistered on April 14, 2020, in the German Clinical Trials Register (registration number DRKS00021405).

Telehealth acceptance and commitment therapy for weight loss: Protocol of the WeLNES full scale randomized controlled trial

Behavioral interventions delivered via one-on-one telephone coaching (hereafter referred to as telehealth) for weight loss have had great population-level reach but to date limited efficacy. Acceptance and Commitment Therapy (ACT) has promise to improve behavioral weight loss treatment efficacy by addressing the fundamental challenges of weight loss and maintenance: overeating in response to internal (e.g., stress) and external (e.g., high calorie foods) cues. Here we describe the Weight Loss, Nutrition, and Exercise Study (WeLNES) randomized controlled trial that is testing the efficacy of an ACT-based telehealth coaching intervention for weight loss in comparison to a Standard Behavioral Therapy (SBT)-based telehealth coaching intervention. A total of 398 adults with overweight or obesity are being recruited and randomized to either ACT or SBT telehealth coaching. Participants in both arms are offered twenty-five telehealth coaching sessions in year one and nine booster sessions in year two. All participants receive a Bluetooth-enabled scale to self-monitor weight and a Fitbit Inspire + Fitbit app for tracking diet and physical activity. The primary aim is to determine whether a greater proportion of ACT participants will achieve a clinically significant weight loss of ≥10% compared with SBT participants at 12-months. Secondary outcomes include change in weight from baseline to 6, 12, and 24-months. Whether the effect of ACT on weight loss is mediated by ACT processes and is moderated by baseline factors will also be examined. If ACT proves efficacious, ACT telehealth coaching will offer an effective, broadly scalable weight loss treatment-thereby making a high public health impact.

A survey with interventional components delivered on tablet devices versus usual care to increase pre-exposure prophylaxis uptake among cisgender Black women: a pilot randomized controlled trial

BACKGROUND

Cisgender (cis) Black women in the USA are more likely to become HIV positive during their lifetime than other women. We developed and implemented a behavioral intervention, Increasing PrEP (iPrEP), the first pilot randomized controlled trial (RCT) aimed at motivating cis Black women to be willing to use PrEP for HIV prevention and attend an initial PrEP clinic visit following an emergency department visit.

METHODS

Eligible participants were Black cisgender women ages 18-55 years who acknowledged recent condomless sex and substance use. Participants were randomized to iPrEP or usual care (UC). iPrEP is a survey-based intervention designed to raise awareness and knowledge about PrEP. Participants completed an assessment of knowledge of and willingness to use PrEP before and after the intervention, then received a warm-hand off with referral to a local PrEP clinic. Enrolled participants were followed for 6 months.

RESULTS

Forty enrolled participants were ages 18-54 years. Education levels varied evenly between some high school education and graduate education. Most participants were single (n = 25) or married (n = 7). Twenty-two participants were employed full-time. Pre-test results indicated that 21 of 40 participants had heard of PrEP. All participants identified PrEP as a daily HIV prevention medication. For those randomized to iPrEP, the odds of knowing about PrEP at post-test, when controlling for baseline, were higher relative to UC (OR = 5.22, 95%CrI = 0.50, 94.1]. iPrEP did not have any effect on willingness relative to UC. The estimate for iPrEP on willingness is marginally higher (4.16 vs. 4.04; i.e., 0.12 points higher); however, the posterior probability of 67.9% does not suggest a strong degree of evidence in favor of an effect. During the post-test, those receiving iPrEP were less ready to take PrEP than those receiving UC.

CONCLUSIONS

Findings suggest that iPrEP increased knowledge about the PrEP medication but had a negative impact on readiness to take PrEP relative to UC. It is imperative that future research among cisgender Black women carefully considers the content provided in interventions designed to increase PrEP use, balancing the benefits of PrEP with the side effects and daily pill burden.

TRIAL REGISTRATION

clinicaltrial.gov Identifier: NCT03930654, 29/04/2019.

Acceptance and Commitment Therapy-Based Smartphone Applications for Cessation of Tobacco Use among Adults with High Nicotine Dependence: Results from the iCanQuit Randomized Trial

Background: With 1 in 2 adult tobacco users being highly dependent on nicotine, population-based interventions specifically designed for this group are urgently needed. This study used data from a randomized trial to evaluate whether (1) Acceptance and Commitment Therapy (ACT) delivered via a smartphone application (iCanQuit) would be more efficacious for cessation of nicotine-containing tobacco products than the US Clinical Practice Guidelines (USCPG)-based application (QuitGuide) among highly nicotine-dependent adults, (2) the effect of treatment on cessation was mediated by increases in acceptance of cravings to smoke, and (3) treatment utilization and satisfaction differed by arm. Methods: A total of 1452 highly nicotine-dependent adults received the iCanQuit or QuitGuide application for 12-months. Cessation outcomes were self-reported complete-case 30-day abstinence of nicotine-containing tobacco products (e.g., combustible cigarettes, e-cigarettes, chewing tobacco, snus, hookahs, cigars, cigarillos, tobacco pipes, and kreteks) at 3, 6, and 12-month post-randomization timepoints, missing-as-smoking, and multiple imputation analyses. Acceptance of cues to smoke and satisfaction with the applications was also reported. Results: Participants who received iCanQuit were significantly more likely to report 30-day abstinence of nicotine-containing tobacco products than those who received QuitGuide at 12-months (24% vs. 17%; OR = 1.47 95% CI: 1.11, 1.95). iCanQuit participants utilized their application more frequently and reported greater satisfaction than those who received QuitGuide. Increases in participants' acceptance of cues to smoke mediated the intervention effect on cessation of nicotine-containing tobacco products. Conclusions: Among nicotine-dependent adults, an application-delivered ACT-based intervention was more engaging and efficacious than a USCPG-based intervention for cessation of nicotine-containing tobacco products.

Apathy as a Predictor of Conversion from Mild Cognitive Impairment to Alzheimer's Disease: A Texas Alzheimer's Research and Care Consortium (TARCC) Cohort-Based Analysis

BACKGROUND

Apathy is among the neuropsychiatric symptoms frequently observed in people with cognitive impairment. It has been postulated to be a potential predictor of conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD).

OBJECTIVE

To detect conversion rates from MCI to AD, and to determine the effect of apathy on the progression to AD in patients with MCI enrolled in the Texas Alzheimer's Research and Care Consortium (TARCC) cohort.

METHODS

Apathy was determined by a positive response to the respective item in the Neuropsychiatric Inventory -Questionnaire (NPI-Q) completed by family members or caregivers. The final dataset included 2,897 observations from 1,092 individuals with MCI at the baseline. Kaplan-Meier survival curves were estimated to provide indices of the probability of conversion to AD over time across all individuals as well as between those with and without apathy. Cox proportional hazards regression measured the hazard associated with apathy and several other predictors of interest.

RESULTS

Over a period of 8.21 years, 17.3% of individuals had conversion from MCI to AD (n = 190 of 1,092 total individuals) across observations. The median time-to-conversion across all participants was 6.41 years. Comparing individuals with apathy (n = 158) versus without apathy (n = 934), 36.1% and 14.2% had conversion to AD, respectively. The median time-to-conversion was 3.79 years for individuals with apathy and 6.83 years for individuals without apathy. Cox proportional hazards regression found significant effects of several predictors, including apathy, on time-to-conversion. Age and cognitive performance were found to moderate the relationship between apathy and time-to-conversion.

CONCLUSIONS

Apathy is associated with progression from MCI to AD, suggesting that it might improve risk prediction and aid targeted intervention delivery.

Alcohol Use Severity, Anger and Drinking Motives among Firefighters

Background: Firefighters represent an understudied population with high rates of hazardous alcohol use and alcohol use disorder. This population is also at an increased risk of mental health disorders and related symptoms such as anger. Anger is a relatively understudied negative mood state with clinical relevance to alcohol use among firefighters. Anger is associated with greater alcohol use and may spur more approach-motivated reasons for drinking compared to other negative emotions. Objectives: This study sought to examine: 1. whether anger significantly contributes to alcohol use severity in firefighters above and beyond general negative mood; 2. which of four validated drinking motives (e.g., coping, social, enhancement and conformity) act as moderators in the relationship between anger and alcohol use severity in this population. The current study is a secondary analysis of data from a larger study examining health and stress behaviors among firefighters (N = 679) at a large urban fire department in the southern United States. Results: Results revealed that anger was positively associated with alcohol use severity, even after controlling for general negative mood. Further, social and enhancement motives for drinking were significant moderators of the relationship between anger and alcohol use severity. Conclusions: These findings identify anger specifically as an important factor to be considered when assessing alcohol use in firefighters, especially those who are drinking to make social experiences more enjoyable or to enhance their mood. These findings can be used to inform more specialized interventions for alcohol use by targeting anger more specifically in firefighters and other male-dominated first-responder populations.