Multiply robust generalized estimating equations for cluster randomized trials with missing outcomes.

Generalized estimating equations (GEEs) provide a useful framework for estimating marginal regression parameters based on data from cluster randomized trials (CRTs), but they can result in inaccurate parameter estimates when some outcomes are informatively missing. Existing techniques to handle missing outcomes in CRTs rely on correct specification of a propensity score model, a covariate-conditional mean outcome model, or require at least one of these two models to be correct, which can be challenging in practice. In this article, we develop new weighted GEEs to simultaneously estimate the marginal mean, scale, and correlation parameters in CRTs with missing outcomes, allowing for multiple propensity score models and multiple covariate-conditional mean models to be specified. The resulting estimators are consistent provided that any one of these models is correct. An iterative algorithm is provided for implementing this more robust estimator and practical considerations for specifying multiple models are discussed. We evaluate the performance of the proposed method through Monte Carlo simulations and apply the proposed multiply robust estimator to analyze the Botswana Combination Prevention Project, a large HIV prevention CRT designed to evaluate whether a combination of HIV-prevention measures can reduce HIV incidence.

Group Coping Intervention in Patients With Chronic Graft-Versus-Host Disease: A Pilot Randomized Clinical Trial.

BACKGROUND: More than half the long-term survivors of allogeneic hematopoietic cell transplantation develop chronic graft-versus-host disease (GVHD), a debilitating inflammatory syndrome. Supportive interventions to assist survivors in coping with chronic GVHD are critically needed. PATIENTS AND METHODS: We conducted a pilot randomized clinical trial of a multidisciplinary group intervention (Horizons Program; n=39) versus minimally enhanced usual care (n=41) for patients with moderate or severe chronic GVHD. Horizons participants received 8 weekly sessions about GVHD and coping co-led by a transplant clinician and a behavioral health expert via a secure videoconferencing platform. Participants completed the following surveys before randomization, at 10 weeks, and at 18 weeks: Functional Assessment of Cancer Therapy-Bone Marrow Transplant Scale (FACT-BMT) for quality of life (QoL), Lee Symptom Scale for symptom burden, and Hospital Anxiety and Depression Scale-Depression Symptoms (HADS) for mood. The primary endpoint was feasibility (≥50% enrollment, ≥80% attendance in half the sessions for the Horizons arm only, and ≥80% retention). We also explored preliminary efficacy of the Horizons intervention on changes in patient-reported outcomes with linear mixed effects models and estimates of effect size at 10 weeks. RESULTS: We enrolled and registered 80 (67.2%) of 119 eligible patients (mean age, 62 years; 48.8% female). Of the participants in the Horizons Program, 84.6% attended at least half the sessions. Of registered participants, 91.3% completed assessment follow-ups (Horizons, 35/39 [89.7%]; minimally enhanced usual care, 38/41 [92.7%]). Horizons participants reported improvements in QoL (b = 2.24; d=0.53), anxiety symptoms (b = -0.10; d=0.34), and depression symptoms (b = -0.71; d=0.44) compared with participants who received minimally enhanced usual care. CONCLUSIONS: Participation in a multidisciplinary group intervention study was feasible for patients with chronic GVHD, with promising signals for improving QoL and mood. A full-scale efficacy trial is needed to confirm effects on patient-reported outcomes.

Quality of Life, Physical Functioning, and Psychological Distress of Older Adults Undergoing Hematopoietic Stem Cell Transplantation.

With advances in therapies for hematologic cancers, older adults increasingly undergo hematopoietic stem cell transplantation (HSCT). Older adults may potentially experience an exaggerated burden of toxicity from HSCT. Studies examining the quality of life (QOL), physical functioning, and psychological symptom trajectory for older adults undergoing HSCT are limited. Our primary aim was to describe the trajectory of QOL, physical functioning, and psychological distress of older adults undergoing HSCT. Secondarily, we aimed to compare the trajectory of QOL, physical functioning, and psychological distress of older and younger adults undergoing HSCT and to evaluate factors associated with QOL trajectory in older adults undergoing HSCT. We conducted secondary analyses of two prospective studies conducted at Massachusetts General Hospital. From 2011 to 2016, we enrolled 250 adults undergoing allogeneic or autologous HSCT. Older age was defined as age ≥65 years. We collected patient-reported outcomes (PROs) within 72 hours of admission for HSCT, at hematologic nadir (2 weeks), and at 6 months after HSCT. To assess QOL, physical functioning, and psychological symptoms, we used the Functional Assessment of Cancer Therapy (FACT)-Bone Marrow Transplant, FACT-Trial Outcome Index, and Patient Health Questionnaire-9, respectively. We used the post-traumatic stress disorder (PTSD) Checklist-Civilian Version to assess PTSD symptoms. We fit linear mixed effects models to characterize trajectories of changes in PROs across timepoints and to evaluate baseline factors associated with QOL trajectories in older adults. Overall 30.4% (76/250) of our cohort was 65 years or older. All older adults undergoing allogeneic HSCT received a reduced intensity conditioning regimen. At 2 weeks after HSCT, older patients experienced a decline in QOL (Δ = -16.6, P < .001), physical functioning (Δ = -15.4, P < .001) and an increase in depression symptoms (Δ = 3.8, P < .001). At 6 months after HSCT, QOL (Δ = 1.4, P = .7), physical functioning (Δ = 1.7, P = .5), and depression symptoms (Δ = 0.4, P = .6) recovered to baseline values. At 6 months after HSCT, the proportion of older patients with PTSD symptoms increased from 5.3% (4/76) at baseline to 13.2% (10/76). There was no significant difference in slopes or trajectories of PROs between older and younger patients. In older adults, baseline psychological distress was associated with significantly worse QOL trajectory (Δ= -21.6, P ≤ .001). Older adults experienced a sharp decline in QOL and physical functioning and an increase in depression symptoms within 2 weeks of HSCT hospitalization. Baseline psychological distress was associated with a pronounced worsening in post-HSCT QOL trajectory. These findings underscore the need for supportive care interventions to improve the experience of older adults undergoing HSCT.

Healthy hearts healthy minds: A randomized trial of online interventions to improve physical activity.

INTRODUCTION: Depressed individuals are more likely to die from cardiovascular disease (CVD) than those without depression. People with CVD have higher rates of depression than those without and have higher mortality rates if they have comorbid depression. While physical activity (PA) improves both, few people engage in enough. We compared self-guided internet-based cognitive behavior therapy (CBT) + Fitbit or mindfulness-based cognitive therapy (MBCT) + Fitbit, with Fitbit only to increase daily steps for participants with depression who have low PA. METHODS: Adult participants (N = 340) were recruited from two online patient-powered research networks and randomized to one of three study interventions for 8 weeks with an additional 8 weeks of follow-up. Using linear mixed effects models, we evaluated the effect of the intervention on average daily steps (NCT03373110). RESULTS: Average daily steps increased 2.8 steps per day in MBCT+Fitbit, 2.9 steps/day in CBT + Fitbit, but decreased 8.2 steps/day in Fitbit Only. These changes were not statistically different between the MBCT+Fitbit and CBT + Fitbit groups, but were different from Fitbit Only across the initial 8-week period. Group differences were not maintained across follow-up. Exploratory analyses identified comorbid anxiety disorders, self-reported PA, and employment status as moderators. DISCUSSION: Changes in daily steps over both 8- and 16-week periods-regardless of intervention group-were minimal. The results emphasize the limits of using self-guided web-based psychotherapy with an activity tracker to increase PA in participants with a history of depression and low PA.

Antiretroviral therapy adherence patterns, virological suppression, and emergence of drug resistance: A nested case-control study from Uganda and South Africa.

BACKGROUND: Relationships between distinct antiretroviral therapy (ART) adherence patterns and risk of drug resistance are not well understood. METHODS: We conducted a nested case-control analysis within a longitudinal cohort study of individuals initiating efavirenz-based ART. Primary outcomes of interest, measured at 6 and 12 months after treatment initiation, were: 1) virologic suppression, 2) virologic failure with resistance, and 3) virologic failure without resistance. Our primary exposure of interest was ART adherence, measured over the 6 months before each visit with electronic pill monitors, and categorized in three ways: 1) 6 months average adherence; 2) running adherence, defined as the proportion of days with average adherence over 9 days of less than or equal to 10%, 20%, and 30%; and 3) number of 3-, 7-, and 28-day treatment gaps in the prior 6 months. RESULTS: We analyzed data from 166 individuals (107 had virologic failure during observation and 59 had virologic suppression at 6 and 12 months). Average adherence was higher among those with virologic suppression (median 83%, IQR 58-96%) versus those with virologic failure with resistance (median 35%, IQR 20-77%, pairwise P < 0.01) and those with virologic failure without resistance (median 21%, IQR 2-54%, pairwise P < 0.01). Although treatment gaps generally predicted virologic failure (P < 0.01), they did not differentiate failure with and without drug resistance (P > 0.6). CONCLUSIONS: Average adherence patterns, but not the assessed frequency of treatment gaps, differentiated failure with versus without drug resistance among individuals initiating efavirenz-based ART. Future work should explore adherence-resistance relationships for integrase inhibitor-based regimens.

Web-Based Mindfulness-Based Interventions for Well-being: Randomized Comparative Effectiveness Trial.

BACKGROUND: Mindfulness can improve overall well-being by training individuals to focus on the present moment without judging their thoughts. However, it is unknown how much mindfulness practice and training are necessary to improve well-being. OBJECTIVE: The primary aim of this study was to determine whether a standard 8-session web-based mindfulness-based cognitive therapy (MBCT) program, compared with a brief 3-session mindfulness intervention, improved overall participant well-being. In addition, we sought to explore whether the treatment effects differed based on the baseline characteristics of the participants (ie, moderators). METHODS: Participants were recruited from 17 patient-powered research networks, web-based communities of stakeholders interested in a common research area. Participants were randomized to either a standard 8-session MBCT or a brief 3-session mindfulness training intervention accessed on the web. The participants were followed for 12 weeks. The primary outcome of the study was well-being, as measured by the World Health Organization-Five Well-Being Index. We hypothesized that MBCT would be superior to a brief mindfulness training. RESULTS: We randomized 4411 participants, 3873 (87.80%) of whom were White and 3547 (80.41%) of female sex assigned at birth. The mean baseline World Health Organization-Five Well-Being Index score was 50.3 (SD 20.7). The average self-reported well-being in each group increased over the intervention period (baseline to 8 weeks; model-based slope for the MBCT group: 0.78, 95% CI 0.63-0.93, and brief mindfulness group: 0.76, 95% CI 0.60-0.91) as well as the full study period (ie, intervention plus follow-up; baseline to 20 weeks; model-based slope for MBCT group: 0.41, 95% CI 0.34-0.48; and brief mindfulness group: 0.33, 95% CI 0.26-0.40). Changes in self-reported well-being were not significantly different between MBCT and brief mindfulness during the intervention period (model-based difference in slopes: -0.02, 95% CI -0.24 to 0.19; P=.80) or during the intervention period plus 12-week follow-up (-0.08, 95% CI -0.18 to 0.02; P=.10). During the intervention period, younger participants (P=.05) and participants who completed a higher percentage of intervention sessions (P=.005) experienced greater improvements in well-being across both interventions, with effects that were stronger for participants in the MBCT condition. Attrition was high (ie, 2142/4411, 48.56%), which is an important limitation of this study. CONCLUSIONS: Standard MBCT improved well-being but was not superior to a brief mindfulness intervention. This finding suggests that shorter mindfulness programs could yield important benefits across the general population of individuals with various medical conditions. Younger people and participants who completed more intervention sessions reported greater improvements in well-being, an effect that was more pronounced for participants in the MBCT condition. This finding suggests that standard MBCT may be a better choice for younger people as well as treatment-adherent individuals. TRIAL REGISTRATION: ClinicalTrials.gov NCT03844321; https://clinicaltrials.gov/ct2/show/NCT03844321.

The relationship between suicidal thoughts and well-being among individuals with a history of depression and cardiovascular risk.

Prior work demonstrates a relationship between suicidal behavior and mood disorders, as well as between suicidal behavior and cardiovascular risk. When cardiovascular risk and mood disorders co-occur, people with these comorbid conditions tend to experience worse outcomes than people with only one of these conditions. As such, given the relevance of suicidal thoughts and behaviors among those with cardiovascular risk and mood disorders, suicidal thoughts and behaviors may be of particular concern in the comorbid population. However, the factors that differentiate those with or without suicidal thoughts or behaviors are unknown. Self-reported well-being is one factor that is shown to hold a relationship with suicidal risk, and may be relevant in the comorbid population. Thus, we evaluated whether different levels of well-being relate to suicidal thoughts and behaviors among individuals (N = 340) with lifetime mood disorders and cardiovascular risk who participated in a 16-week online exercise study. Participants completed self-report assessments of lifetime (per the MINI International Neuropsychiatric Interview) and current (per the Patient Health Questionnaire-9) suicidal thoughts and behaviors, as well as a self-report assessment of well-being (per the WHO-5 Well-Being Index). We found that individuals with lifetime and current suicidal thinking had lower total WHO-5 scores over the study period. These data suggest that, among those with a history of depression and who have or are at-risk for cardiovascular disease, the risk of current or lifetime suicidal thoughts and behaviors may be increased for those who experience decreased well-being.

Study protocol for a randomised trial evaluating the non-inferiority of stepped palliative care versus early integrated palliative care for patients with advanced lung cancer.

INTRODUCTION: Integrating palliative care (PC) early in the illness course for patients with serious cancers improves their outcomes and is recommended by national organisations such as the American Society of Clinical Oncology. However, monthly visits with PC clinicians from the time of diagnosis can be challenging to implement due to the lack of specialty-trained PC clinicians and resources. Therefore, we developed a stepped care model to triage PC service based on patients' needs. METHODS AND ANALYSIS: We are conducting a non-blinded, randomised trial to evaluate the non-inferiority of a stepped PC model compared with an early integrated PC model for improving patients' quality of life (QOL) at 24 weeks (primary outcome). Patients assigned to early integrated PC meet with PC every 4 weeks throughout their illness. Patients assigned to stepped PC have PC visits only at clinically significant points in their illness (eg, cancer progression) unless their QOL decreases, at which time they are 'stepped up' and meet with PC every 4 weeks throughout the remainder of their illness. Secondary aims include assessing whether stepped PC is non-inferior to early integrated PC regarding patient-clinician communication about end of life care and length of stay on hospice as well as comparing resource utilisation. Patients are recruited from the Massachusetts General Hospital Cancer Center, Boston, Massachusetts; Duke Cancer Center, Durham, North Carolina and University of Pennsylvania Abramson Cancer Center, Philadelphia, Pennsylvania. The target sample size is 510 patients. ETHICS AND DISSEMINATION: The study is funded by the National Cancer Institute, approved by the Dana-Farber/Harvard Cancer Center Institutional Review Board and will be reported in accordance with the Consolidated Standards of Reporting Trials statement. We will disseminate results through professional society meetings, peer-reviewed publications and presentations to patient organisations. TRIAL REGISTRATION NUMBER: NCT03337399.

Moderators of a resiliency group intervention for frontline clinicians during the COVID-19 pandemic.

BACKGROUND: To mitigate the psychological burdens of COVID-19 for frontline clinicians (FCs), we adapted an existing evidence-based resiliency program, Stress Management and Resilience Training Relaxation Response Program (SMART-3RP), for FCs. This analysis explores moderators of stress coping to determine which subgroups of FCs benefited most from SMART-3RP. METHODS: 102 FCs from Mass General Brigham hospitals engaged in the adapted SMART-3RP. Assessments were completed at group entry (Week 0) and completion (Week 4). The primary outcome was stress coping, and we examined 15 possible baseline moderators. We fit linear mixed effects regression models and assessed potential baseline moderators using a likelihood ratio test. We report model-based estimates and confidence intervals for each moderator-by-time interaction (i.e., differential effect), where positive/negative values indicate more/less improvement in average perceived stress coping. RESULTS: Stress coping improved from Week 0 to Week 4 (mean improvement [95% CI] = 0.9 [0.6 to 1.2]). FCs with higher anxiety (differential effect [95% CI] = 0.3 [0.1 to 0.4]), depression (0.4 [0.2 to 0.6]), and loneliness (0.4 [0.1 to 0.6]), but lower levels of mindfulness (CAMS-Rfocus: 1.0 [0.4 to 1.6]; CAMS-Raccept: 1.3 [0.7 to 2.0]) and self-compassion (0.4, [0.1 to 0.8]) at baseline experienced greater benefits in perceived stress coping from the SMART-3RP. Baseline health uncertainty along with sociodemographic and work characteristics did not moderate stress coping. DISCUSSION: Results highlight particular sub-populations of FCs that may benefit more from a stress management intervention, especially during emergency responses (e.g., COVID-19 pandemic).

Illness stage and predominant polarity in bipolar disorder: Correlation with burden of illness and moderation of treatment outcome.

Bipolar disorder often follows a set progression best described in stages where advanced stages are associated with poorer outcomes. Bipolar disorder is also often characterized by a predominance of episode polarity, where some individuals experience more depressive episodes (termed predominant depressive polarity) while others experience more hypo/manic episodes (termed predominant hypo/manic polarity). We examined the associations between staging and predominant polarity with measures of illness burden and treatment outcome utilizing data from a six-month comparative effectiveness trial of lithium and quetiapine in bipolar disorder (Bipolar CHOICE). We used number of self-reported lifetime mood (depressive and hypo/manic) episodes as a proxy for staging and ratio of depressive to manic episodes to define predominant polarity. Polarity and staging were correlated with several measures of burden of illness. Childhood abuse was correlated with more lifetime mood episodes, while more depressive episodes and depressive polarity were correlated with more anxiety disorder comorbidity. Depressive polarity was also correlated with more past trials of psychotropics, particularly antidepressants. However, neither staging nor predominant polarity moderated the randomized treatment effect of lithium vs. quetiapine. Number of depressive episodes in the past year was identified as a potential predictor of overall worse treatment outcome, regardless of medication condition. In conclusion, though staging and predominant episode polarity correlated with several measures of illness burden, they were not associated with differential treatment outcomes. This could be because many of our patients presented for treatment at advanced stages of illness and further highlights the need for early intervention in bipolar disorder.

Randomization-based inference for a marginal treatment effect in stepped wedge cluster randomized trials.

In a cross-sectional stepped wedge cluster randomized trial (SWT), clusters are randomized to crossover from control to intervention at different time periods and outcomes are assessed for a different set of individuals in each cluster-period. Randomization-based inference is an attractive analysis strategy for SWTs because it does not require full parametric specification of the outcome distribution or correlation structure and its validity does not rely on having a large number of clusters. Existing randomization-based approaches for SWTs, however, either focus on hypothesis testing and omit technical details on confidence interval (CI) calculation with noncontinuous outcomes, or employ weighted cluster-period summary statistics for p-value and CI calculation, which can result in suboptimal efficiency if weights do not incorporate information on varying cluster-period sizes. In this article, we propose a framework for calculating randomization-based p-values and CIs for a marginal treatment effect in SWTs by using test statistics derived from individual-level generalized linear models. We also investigate how study design features, such as stratified randomization, subsequently impact various SWT analysis methods including the proposed approach. Data from the XpertMTB/RIF tuberculosis trial are reanalyzed to illustrate our method and compare it to alternatives.

Randomization-based confidence intervals for cluster randomized trials.

In a cluster randomized trial (CRT), groups of people are randomly assigned to different interventions. Existing parametric and semiparametric methods for CRTs rely on distributional assumptions or a large number of clusters to maintain nominal confidence interval (CI) coverage. Randomization-based inference is an alternative approach that is distribution-free and does not require a large number of clusters to be valid. Although it is well-known that a CI can be obtained by inverting a randomization test, this requires testing a non-zero null hypothesis, which is challenging with non-continuous and survival outcomes. In this article, we propose a general method for randomization-based CIs using individual-level data from a CRT. This approach accommodates various outcome types, can account for design features such as matching or stratification, and employs a computationally efficient algorithm. We evaluate this method's performance through simulations and apply it to the Botswana Combination Prevention Project, a large HIV prevention trial with an interval-censored time-to-event outcome.

Bipolar depression and suicidal ideation: Moderators and mediators of a complex relationship.

INTRODUCTION: Not all patients with bipolar depression have suicidal ideation (SI). This study examines some factors that link bipolar depression to SI. METHODS: 482 individuals with bipolar I or II were randomized to either lithium or quetiapine plus adjunctive personalized therapy in a 24 week comparative effectiveness trial. Severity of depression and SI were assessed with the Bipolar Inventory of Symptoms Scale (BISS). We examined potential moderators (age, gender, age of illness onset, bipolar type, comorbid anxiety, substance use, past suicide attempts, childhood abuse and treatment arm) and mediators (severity of anxiety, mania, irritability, impairment in functioning (LIFE-RIFT) and satisfaction and enjoyment of life (Q-LES-Q)) of the effect of depression on SI. Statistical analyses were conducted using generalized estimating equations with repeated measures. RESULTS: Bipolar type and past suicide attempts moderated the effect of depression on SI. Life satisfaction mediated the effect of depression and SI. The relationship between anxiety, depression and SI was complex due to the high level of correlation. Treatment with lithium or quetiapine did not moderate the effect of depression on SI. LIMITATIONS: Suicide assessment was only done using an item on BISS. Patient population was not specifically chosen for high suicide risk. DISCUSSION: Individuals with Bipolar II experienced more SI with lower levels of depression severity. A history of suicide predisposed patients to higher levels of SI given the same severity of depression. Reduced life satisfaction mediates the effect of depression on SI and may be a target for therapeutic interventions.

Comorbid anxiety in bipolar CHOICE: Insights from the bipolar inventory of symptoms scale.

BACKGROUND: Approximately 86-89% of patients with BD have a comorbid anxiety disorder associated with poor quality of life and reduced likelihood of recovery from an acute mood episode. The purpose of this study is to assess the prevalence and impact of comorbid anxiety using the Bipolar Inventory of Symptoms Scale (BISS) in patients with BD who participated in a 6-month pragmatic trial. METHODS: Participants (N = 482) in the Bipolar Clinical Health Outcomes Initiative in Comparative Effectiveness (CHOICE) study were adults with BD I or II. Anxiety diagnoses were assessed with the MINI. Global illness severity was assessed using the Clinical Global Impression-Bipolar Version. Mood symptoms and anxiety severity were assessed using the BISS. RESULTS: 61% of the study sample met criteria for a current anxiety disorder. Patients with a higher BISS anxiety score at baseline had a higher overall BD illness severity, depressive severity, and manic episode severity (p < 0.001). A single cutoff value of BISS anxiety had great sensitivity, yet poor specificity for determining a comorbid anxiety diagnosis. There were no significant differences in outcomes for individuals treated for anxiety disorders with anxiolytics compared with those who were not treated with anxiolytics. LIMITATIONS: Sample size limitations prevented an analysis of whether the BISS cutoff score of 10 performed differently across varied anxiety disorders. CONCLUSIONS: Given its ability to identify patients with co-occurring anxiety, the BISS anxiety subscale shows clinical utility as a screening measure though its application as a clinical assessment measure may not be advisable.

Sleep disturbance may impact treatment outcome in bipolar disorder: A preliminary investigation in the context of a large comparative effectiveness trial.

BACKGROUND: Bipolar patients experience sleep disturbances during and between mood episodes. Yet the impact of sleep on treatment with different medications has not been fully explored. The purpose of this paper is to explore the potential impact of poor sleep at baseline on outcomes in a randomized effectiveness trial of quetiapine and lithium. METHODS: The Bipolar CHOICE study was a 6-month, parallel group, multisite randomized controlled trial. Participants with bipolar disorder (N = 482; 59% female and age 18-70 years) received quetiapine or lithium. Patients were allowed to also receive adjunctive personalized treatments, which were guideline-informed, empirically-based medications added to treatment as needed. Medication changes were recorded as necessary clinical adjustments (NCA). Fisher's exact tests, mixed-regression models, and Mann-Whitney U tests were used to assess demographic and clinical characteristics as well as whether sleep disturbance would predict outcomes. RESULTS: 63% of patients had baseline sleep disturbance. Individuals with sleep disturbance had worse bipolar illness severity, greater severity of depression, mania, anxiety, irritability, and psychosis, were less likely to have sustained response (17% vs. 29%; adjusted RR: 0.55, 95% CI: 0.38-0.78, p = 0.0006) and had more NCAs (median 0.71 vs. 0.59, p = 0.03). LIMITATIONS: Our findings were limited by how we defined sleep disturbance, and by how severity of sleep disturbance was assessed with one item with a non-sleep specific measure. CONCLUSIONS: Baseline sleep disturbance was associated with more severe bipolar symptoms and worse 6-month outcomes. Further research is warranted on improving sleep in bipolar disorder, especially the role of psychosocial interventions.

Implementing Generalized Additive Models to Estimate the Expected Value of Sample Information in a Microsimulation Model: Results of Three Case Studies.

BACKGROUND: The expected value of sample information (EVSI) can help prioritize research but its application is hampered by computational infeasibility, especially for complex models. We investigated an approach by Strong and colleagues to estimate EVSI by applying generalized additive models (GAM) to results generated from a probabilistic sensitivity analysis (PSA). METHODS: For 3 potential HIV prevention and treatment strategies, we estimated life expectancy and lifetime costs using the Cost-effectiveness of Preventing AIDS Complications (CEPAC) model, a complex patient-level microsimulation model of HIV progression. We fitted a GAM-a flexible regression model that estimates the functional form as part of the model fitting process-to the incremental net monetary benefits obtained from the CEPAC PSA. For each case study, we calculated the expected value of partial perfect information (EVPPI) using both the conventional nested Monte Carlo approach and the GAM approach. EVSI was calculated using the GAM approach. RESULTS: For all 3 case studies, the GAM approach consistently gave similar estimates of EVPPI compared with the conventional approach. The EVSI behaved as expected: it increased and converged to EVPPI for larger sample sizes. For each case study, generating the PSA results for the GAM approach required 3 to 4 days on a shared cluster, after which EVPPI and EVSI across a range of sample sizes were evaluated in minutes. The conventional approach required approximately 5 weeks for the EVPPI calculation alone. CONCLUSION: Estimating EVSI using the GAM approach with results from a PSA dramatically reduced the time required to conduct a computationally intense project, which would otherwise have been impractical. Using the GAM approach, we can efficiently provide policy makers with EVSI estimates, even for complex patient-level microsimulation models.

Serial Heart Rates, Guideline-Directed Beta Blocker Use, and Outcomes in Patients With Chronic Heart Failure With Reduced Ejection Fraction.

A single heart rate (HR) measurement may inform future prognosis in chronic heart failure with reduced ejection fraction (HFrEF). The importance of elevated HR across serial assessment is uncertain, particularly with well-applied guideline-directed medical therapy (GDMT) with beta blockers (BBs). In this post hoc analysis of 129 patients with chronic HFrEF in sinus rhythm, who had aggressive medication titration over 10.6 months, HR and BB use were assessed at each visit (average of 6 visits per patient). All-cause mortality was assessed. At baseline, 81 subjects (62.8%) had HR ≥70 beats/min; 40 subjects (31.0%) had high HR despite being on ≥50% of GDMT BB dose. At final visit, 30.4% of the subjects still had high HR despite achieving ≥50% target BB dose. There were no significant baseline differences in demographics or BB doses in patients with HR <70 vs HR ≥70 beats/min. In adjusted model in which HR was treated as time-dependent covariate, an increase in HR of 10 beats/min was associated with an increased hazard of all-cause mortality during follow-up (adjusted hazard ratio per 10 beats/min = 2.46; 95% confidence interval 1.46-4.16, p <0.001). In conclusion, in well-managed patients with HFrEF, high HR was frequent even after aggressive medication titration, and often despite being on at least 50% of GDMT BB dose. An increase in HR was associated with worse clinical outcomes (Clinicaltrials.gov NCT#00351390).

Clinical correlates of acute bipolar depressive episode with psychosis.

BACKGROUND: Psychotic bipolar depressive episodes remain remarkably understudied despite being common and having a significant impact on bipolar disorder. The aim of this study is to identify the characteristics of depressed bipolar patients with current psychosis compared to those without psychosis. METHODS: We used baseline data of a comparative effectiveness study of lithium and quetiapine for bipolar disorder (the Bipolar CHOICE study) to compare demographic, clinical, and functioning variables between those with and without psychotic symptoms. Of the 482 participants, 303 (62.9%) were eligible for the present study by meeting DSM-IV criteria for an acute bipolar depressive episode. Univariate analyses were conducted first, and then included in a model controlling for symptom severity. RESULTS: The sample was composed mostly of women (60.7%) and the mean age was 39.5±12.1 years. Psychosis was present in 10.6% (n=32) of the depressed patients. Psychotic patients had less education, lower income, and were more frequently single and unemployed. Psychosis was also associated with a more severe depressive episode, higher suicidality, more comorbid conditions and worse functioning. Most group differences disappeared when controlling for depression severity. LIMITATIONS: Only outpatients were included and the presence of psychosis in previous episodes was not assessed. CONCLUSION: Psychosis during bipolar depressive episodes is present even in an outpatient sample. Psychotic, depressed patients have worse illness outcomes, but future research is necessary to confirm if these outcomes are only associated with the severity of the disorder or if some of them are independent of it.