Duration of Adjunctive Antidepressant Maintenance in Bipolar I Depression.

BACKGROUND: Antidepressants are used to treat acute depression in patients with bipolar I disorder, but their effect as maintenance treatment after the remission of depression has not been well studied. METHODS: We conducted a multisite, double-blind, randomized, placebo-controlled trial of maintenance of treatment with adjunctive escitalopram or bupropion XL as compared with discontinuation of antidepressant therapy in patients with bipolar I disorder who had recently had remission of a depressive episode. Patients were randomly assigned in a 1:1 ratio to continue treatment with antidepressants for 52 weeks after remission or to switch to placebo at 8 weeks. The primary outcome, assessed in a time-to-event analysis, was any mood episode, as defined by scores on scales measuring symptoms of hypomania or mania, depression, suicidality, and mood-episode severity; additional treatment or hospitalization for mood symptoms; or attempted or completed suicide. Key secondary outcomes included the time to an episode of mania or hypomania or depression. RESULTS: Of 209 patients with bipolar I disorder who participated in an open-label treatment phase, 150 who had remission of depression were enrolled in the double-blind phase in addition to 27 patients who were enrolled directly. A total of 90 patients were assigned to continue treatment with the prescribed antidepressant for 52 weeks (52-week group) and 87 were assigned to switch to placebo at 8 weeks (8-week group). The trial was stopped before full recruitment was reached owing to slow recruitment and funding limitations. At 52 weeks, 28 of the patients in the 52-week group (31%) and 40 in the 8-week group (46%) had a primary-outcome event. The hazard ratio for time to any mood episode in the 52-week group relative to the 8-week group was 0.68 (95% confidence interval [CI], 0.43 to 1.10; P = 0.12 by log-rank test). A total of 11 patients in the 52-week group (12%) as compared with 5 patients in the 8-week group (6%) had mania or hypomania (hazard ratio, 2.28; 95% CI, 0.86 to 6.08), and 15 patients (17%) as compared with 35 patients (40%) had recurrence of depression (hazard ratio, 0.43; 95% CI, 0.25 to 0.75). The incidence of adverse events was similar in the two groups. CONCLUSIONS: In a trial involving patients with bipolar I disorder and a recently remitted depressive episode, adjunctive treatment with escitalopram or bupropion XL that continued for 52 weeks did not show a significant benefit as compared with treatment for 8 weeks in preventing relapse of any mood episode. The trial was stopped early owing to slow recruitment and funding limitations. (Funded by the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00958633.).

Study of Rivaroxaban for Cerebral Venous Thrombosis: A Randomized Controlled Feasibility Trial Comparing Anticoagulation With Rivaroxaban to Standard-of-Care in Symptomatic Cerebral Venous Thrombosis.

BACKGROUND: Emerging data suggest that direct oral anticoagulants may be a suitable choice for anticoagulation for cerebral venous thrombosis (CVT). However, conducting high-quality trials in CVT is challenging as it is a rare disease with low rates of adverse outcomes such as major bleeding and functional dependence. To facilitate the design of future CVT trials, SECRET (Study of Rivaroxaban for Cerebral Venous Thrombosis) assessed (1) the feasibility of recruitment, (2) the safety of rivaroxaban compared with standard-of-care anticoagulation, and (3) patient-centered functional outcomes. METHODS: This was a phase II, prospective, open-label blinded-end point 1:1 randomized trial conducted at 12 Canadian centers. Participants were aged ≥18 years, within 14 days of a new diagnosis of symptomatic CVT, and suitable for oral anticoagulation; they were randomized to receive rivaroxaban 20 mg daily, or standard-of-care anticoagulation (warfarin, target international normalized ratio, 2.0-3.0, or low-molecular-weight heparin) for 180 days, with optional extension up to 365 days. Primary outcomes were annual rate of recruitment (feasibility); and a composite of symptomatic intracranial hemorrhage, major extracranial hemorrhage, or mortality at 180 days (safety). Secondary outcomes included recurrent venous thromboembolism, recanalization, clinically relevant nonmajor bleeding, and functional and patient-reported outcomes (modified Rankin Scale, quality of life, headache, mood, fatigue, and cognition) at days 180 and 365. RESULTS: Fifty-five participants were randomized. The rate of recruitment was 21.3 participants/year; 57% of eligible candidates consented. Median age was 48.0 years (interquartile range, 38.5-73.2); 66% were female. There was 1 primary event (symptomatic intracranial hemorrhage), 2 clinically relevant nonmajor bleeding events, and 1 recurrent CVT by day 180, all in the rivaroxaban group. All participants in both arms had at least partial recanalization by day 180. At enrollment, both groups on average reported reduced quality of life, low mood, fatigue, and headache with impaired cognitive performance. All metrics improved markedly by day 180. CONCLUSIONS: Recruitment targets were reached, but many eligible participants declined randomization. There were numerically more bleeding events in patients taking rivaroxaban compared with control, but rates of bleeding and recurrent venous thromboembolism were low overall and in keeping with previous studies. Participants had symptoms affecting their well-being at enrollment but improved over time. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03178864.

T1Gd is reduced in bone marrow lesions overlying cartilage in the hip.

OBJECTIVE: Bone Marrow Lesions (BMLs) are areas in bone with high fluid signal on MRI associated with painful and progressive OA. While cartilage near BMLs in the knee has been shown to be degenerated, this relationship has not been investigated in the hip. RESEARCH QUESTION: is T1Gd lower in areas of cartilage overlying BMLs in the hip? DESIGN: 128 participants were recruited from a population-based study of hip pain in 20-49-year-olds. Proton-density weighted fat-suppressed and delayed Gadolinium Enhanced MR Imaging of Cartilage (dGEMRIC) images were acquired to locate BMLs and quantify hip cartilage health. BML and cartilage images were registered and cartilage was separated into BML overlying and surrounding regions. Mean T1Gd was measured in 32 participants with BMLs in both cartilage regions and in matched regions in 32 age- and sex-matched controls. Mean T1Gd in the overlying cartilage was compared using linear mixed-effects models between BML and control groups for acetabular and femoral BMLs, and between cystic and non-cystic BML groups. RESULTS: Mean T1Gd of overlying cartilage was lower in the BML group compared to the control group (acetabular: -105 ms; 95% CI: -175, -35; femoral: -8 ms; 95% CI: -141, 124). Mean T1Gd in overlying cartilage was lower in cystic compared to non-cystic BML subjects, but the confidence interval is too large to provide certainty in this difference (-3 [95% CI: -126, 121]). CONCLUSIONS: T1Gd is reduced in overlying cartilage in hips from a population-based sample of adults aged 20-49, which suggests BMLs are associated with local cartilage degeneration in hips.

Role of latent tuberculosis infection on elevated risk of cardiovascular disease: a population-based cohort study of immigrants in British Columbia, Canada, 1985-2019.

We investigated cardiovascular disease (CVD) risk associated with latent tuberculosis infection (LTBI) (Aim-1) and LTBI therapy (Aim-2) in British Columbia, a low-tuberculosis-incidence setting. 49,197 participants had valid LTBI test results. Cox proportional hazards model was fitted, adjusting for potential confounders. Compared with the participants who tested LTBI negative, LTBI positive was associated with an 8% higher CVD risk in complete case data (adjusted hazard ratio (HR): 1.08, 95% CI: 0.99-1.18), a statistically significant 11% higher risk when missing confounder values were imputed using multiple imputation (HR: 1.11, 95% CI: 1.02-1.20), and 10% higher risk when additional proxy variables supplementing known unmeasured confounders were incorporated in the highdimensional disease risk score technique to reduce residual confounding (HR: 1.10, 95% CI: 1.01-1.20). Also, compared with participants who tested negative, CVD risk was 27% higher among people who were LTBI positive but incomplete LTBI therapy (HR: 1.27, 95% CI: 1.04-1.55), whereas the risk was similar in people who completed LTBI therapy (HR: 1.04, 95% CI: 0.87-1.24). Findings were consistent in different sensitivity analyses. We concluded that LTBI is associated with an increased CVD risk in low-tuberculosis-incidence settings, with a higher risk associated with incomplete LTBI therapy and attenuated risk when therapy is completed.

Age and sex-related comparison of referral-based telemedicine service utilization during the COVID-19 pandemic in Ontario: a retrospective analysis.

BACKGROUND: The COVID-19 pandemic has led to increased utilization of telemedicine services. METHODS: A retrospective analysis of all referral-based ambulatory telemedicine services in Ontario from November 2019 to June 2021 was collected from the Ontario Health Insurance Plan (OHIP) billing database. Only fee-for-service billings were included in the present analysis. Coincident COVID-19 cases were obtained from Public Health Ontario. Comparisons were made based on age bracket, sex, telemedicine and in-person care. RESULTS: Billings for telemedicine services in Ontario increased from $1.7 million CAD in November 2019 to $64 million CAD in April 2020 and the proportions reached a mean peak of 72% in April 2020 and declined to 46% in June 2021. A positive correlation was found between the use of telemedicine and COVID-19 cases (p = 0.05). The age group with the highest proportion of telemedicine use was the 10-20-year-olds, followed by the 20-50-year-olds (61 ± 9.0%, 55 ± 7.3%, p = 0.01). Both age groups remained above 50% telemedicine services at the end of the study period. There seemed to be higher utilization by females (females 54.2 ± 8.0%, males 47.9 ± 7.7%, ANCOVA p = 0.05) for all specialties, however, after adjusting for male to female ratio m:f of 0.952:1.0 according to the 2016 census, this was no longer significant. CONCLUSIONS: The use of telemedicine services remained at a high level across groups, particularly the 10-50-year-olds. There were clear age preferences for using telemedicine. Studying these differences may provide insights into how the delivery of non-hospital-based medicine has changed during the COVID-19 pandemic.

Reducing the burden of low back pain: results from a new microsimulation model.

BACKGROUND: Low back pain (LBP) causes the highest morbidity burden globally. The purpose of the present study was to project and compare the impact of three strategies for reducing the population health burden of LBP: weight loss, ergonomic interventions, and an exercise program. METHODS: We have developed a microsimulation model of LBP in Canada using a new modeling platform called SimYouLate. The initial population was derived from Cycle 1 (2001) of the Canadian Community Health Survey (CCHS). We modeled an open population 20 years of age and older. Key variables included age, sex, education, body mass index (BMI), type of work, having back problems, pain level in persons with back problems, and exercise participation. The effects of interventions on the risk of LBP were obtained from the CCHS for the effect of BMI, the Global Burden of Disease Study for occupational risks, and a published meta-analysis for the effect of exercise. All interventions lasted from 2021 to 2040. The population health impact of the interventions was calculated as a difference in years lived with disability (YLDs) between the base-case scenario and each intervention scenario, and expressed as YLDs averted per intervention unit or a proportion (%) of total LBP-related YLDs. RESULTS: In the base-case scenario, LBP in 2020 was responsible for 424,900 YLDs in Canada and the amount increased to 460,312 YLDs in 2040. The effects of the interventions were as follows: 27,993 (95% CI 23,373, 32,614) YLDs averted over 20 years per 0.1 unit change in log-transformed BMI (9.5% change in BMI) among individuals who were overweight and those with obesity, 19,416 (16,275, 22,557) YLDs per 1% reduction in the proportion of workers exposed to occupational risks, and 26,058 (22,455, 29,661) YLDs averted per 1% increase in the proportion of eligible patients with back problems participating in an exercise program. CONCLUSIONS: The study provides new data on the relationship between three types of interventions and the resultant reductions in LBP burden in Canada. According to our model, each of the interventions studied could potentially result in a substantial reduction in LBP-related disability.

Magnetic resonance imaging predictors (cartilage, osteophytes and meniscus) of prevalent and 3-year incident medial and lateral tibiofemoral knee joint tenderness and patellofemoral grind.

OBJECTIVE: To identify magnetic resonance imaging (MRI) predictors (cartilage [C], osteophytes [O] and meniscus [M] scores) of prevalent and 3-year incident medial tibiofemoral (MTF) and lateral tibiofemoral (LTF) knee joint tenderness and patellofemoral (PF) grind.  METHODS: Population-based knee pain cohort aged 40-79 was assessed at baseline (N = 255), 3- and 7-year follow-up (N = 108 × 2 = 216). COM scores were measured at 6/8/6 subregions respectively. Age-sex-BMI adjusted logistic models predicted prevalence versus relevant COM predictors (medial, lateral or patellar / trochlear groove scores). Fully adjusted models also included all relevant COM predictors. Binary generalized estimating equations models predicting 3-year incidence were also adjusted for individual follow-up time between cycles. RESULTS: Significant predictors of prevalent MTF tenderness: medial femoral cartilage (fully adjusted odds ratio [aOR] 1.84; 95% confidence interval [CI] 1.11, 3.05), female (aOR = 3.05; 1.67, 5.58), BMI (aOR = 1.53 per 5 units BMI; 1.10, 2.11). Predictors of prevalent LTF tenderness: female (aOR = 2.18; 1.22, 3.90). There were no predictors of prevalent PF grind in the fully adjusted model. However, medial patellar osteophytes was predictive in the age-sex-BMI adjusted model. There were no predictors of 3-year incident MTF tenderness. Predictors of 3-year incident LTF tenderness: female (aOR = 3.83; 1.25, 11.77). Predictors of 3-year incident PF grind: lateral patellar osteophytes (aOR = 4.82; 1.69, 13.77). In the age-sex-BMI adjusted model, patellar cartilage was also a predictor. CONCLUSION: We explored potential MRI predictors of prevalent and 3-year incident MTF/LTF knee joint tenderness and PF grind. These findings could guide preemptive strategies aimed at reducing these symptoms in the present and future (3-year incidence).

The Community-Level Interventions for Pre-eclampsia (CLIP) cluster randomised trials in Mozambique, Pakistan, and India: an individual participant-level meta-analysis.

BACKGROUND: To overcome the three delays in triage, transport and treatment that underlie adverse pregnancy outcomes, we aimed to reduce all-cause adverse outcomes with community-level interventions targeting women with pregnancy hypertension in three low-income countries. METHODS: In this individual participant-level meta-analysis, we de-identified and pooled data from the Community-Level Interventions for Pre-eclampsia (CLIP) cluster randomised controlled trials in Mozambique, Pakistan, and India, which were run in 2014-17. Consenting pregnant women, aged 12-49 years, were recruited in their homes. Clusters, defined by local administrative units, were randomly assigned (1:1) to intervention or control groups. The control groups continued local standard of care. The intervention comprised community engagement and existing community health worker-led mobile health-supported early detection, initial treatment, and hospital referral of women with hypertension. For this meta-analysis, as for the original studies, the primary outcome was a composite of maternal or perinatal outcome (either maternal, fetal, or neonatal death, or severe morbidity for the mother or baby), assessed by unmasked trial surveillance personnel. For this analysis, we included all consenting participants who were followed up with completed pregnancies at trial end. We analysed the outcome data with multilevel modelling and present data with the summary statistic of adjusted odds ratios (ORs) with 95% CIs (fixed effects for maternal age, parity, maternal education, and random effects for country and cluster). This meta-analysis is registered with PROSPERO, CRD42018102564. FINDINGS: Overall, 44 clusters (69 330 pregnant women) were randomly assigned to intervention (22 clusters [36 008 pregnancies]) or control (22 clusters [33 322 pregnancies]) groups. 32 290 (89·7%) pregnancies in the intervention group and 29 698 (89·1%) in the control group were followed up successfully. Median maternal age of included women was 26 years (IQR 22-30). In the intervention clusters, 6990 group and 16 691 home-based community engagement sessions and 138 347 community health worker-led visits to 20 819 (57·8%) of 36 008 women (of whom 11 095 [53·3%] had a visit every 4 weeks) occurred. Blood pressure and dipstick proteinuria were assessed per protocol. Few women were eligible for methyldopa for severe hypertension (181 [1%] of 20 819) or intramuscular magnesium sulfate for pre-eclampsia (198 [1%]), of whom most accepted treatment (162 [89·5%] of 181 for severe hypertension and 133 [67·2%] of 198 for pre-eclampsia). 1255 (6%) were referred to a comprehensive emergency obstetric care facility, of whom 864 (82%) accepted the referral. The primary outcome was similar in the intervention (7871 [24%] of 32 290 pregnancies) and control clusters (6516 [22%] of 29 698; adjusted OR 1·17, 95% CI 0·90-1·51; p=0·24). No intervention-related serious adverse events occurred, and few adverse effects occurred after in-community treatment with methyldopa (one [2%] of 51; India only) and none occurred after in-community treatment with magnesium sulfate or during transport to facility. INTERPRETATION: The CLIP intervention did not reduce adverse pregnancy outcomes. Future community-level interventions should expand the community health worker workforce, assess general (rather than condition-specific) messaging, and include health system strengthening. FUNDING: University of British Columbia, a grantee of the Bill & Melinda Gates Foundation.

Rapid Agitation Control With Ketamine in the Emergency Department: A Blinded, Randomized Controlled Trial.

STUDY OBJECTIVE: We hypothesized that the use of intramuscular ketamine would result in a clinically relevant shorter time to target sedation. METHODS: We conducted a randomized clinical trial comparing the rapidity of onset, level of sedation, and adverse effect profile of ketamine compared to a combination of midazolam and haloperidol for behavioral control of emergency department patients with severe psychomotor agitation. We included patients with severe psychomotor agitation measured by a Richmond Agitation Score (RASS) ≥+3. Patients in the ketamine group were treated with a 5 mg/kg intramuscular injection. Patients in the midazolam and haloperidol group were treated with a single intramuscular injection of 5 mg midazolam and 5 mg haloperidol. The primary outcome was the time, in minutes, from study medication administration to adequate sedation, defined as RASS ≤-1. Secondary outcomes included the need for rescue medications and serious adverse events. RESULTS: Between June 30, 2018, and March 13, 2020, we screened 308 patients and enrolled 80. The median time to sedation was 14.7 minutes for midazolam and haloperidol versus 5.8 minutes for ketamine (difference 8.8 minutes [95% confidence interval (CI) 3.0 to 14.5]). Adjusted Cox proportional model analysis favored the ketamine arm (hazard ratio 2.43, 95% CI 1.43 to 4.12). Five (12.5%) patients in the ketamine arm and 2 (5.0%) patients in the midazolam and haloperidol arm experienced serious adverse events (difference 7.5% [95% CI -4.8% to 19.8%]). CONCLUSION: In ED patients with severe agitation, intramuscular ketamine provided significantly shorter time to adequate sedation than a combination of intramuscular midazolam and haloperidol.

Improving efficiency in the stepped-wedge trial design via Bayesian modeling with an informative prior for the time effects.

BACKGROUND: In a cross-sectional stepped-wedge cluster randomized trial comparing usual care to a new intervention, treatment allocation and time are correlated by design because participants enrolled early in the trial predominantly receive usual care while those enrolled late in the trial predominantly receive the new intervention. Current guidelines recommend adjustment for time effects when analyzing stepped-wedge cluster randomized trials to remove the confounding bias induced by this correlation. However, adjustment for time effects impacts study power. Within the Frequentist framework, adopting a sample size calculation that includes time effects would ensure the trial having adequate power regardless of the magnitude of the effect of time on the outcome. But if in fact time effects were negligible, this would overestimate the required sample size and could lead to the trial being deemed infeasible due to cost or unavailability of the required numbers of clusters or participants. In this study, we explore the use of prior information on time effects to potentially reduce the required sample size of the trial. METHODS: We applied a Bayesian approach to incorporate the prior information on the time effects into cluster-level statistical models (for continuous, binary, or count outcomes) for the stepped-wedge cluster randomized trial. We conducted simulations to illustrate how the bias in the intervention effect estimate and the trial power vary as a function of the prior precision and the mis-specification of the prior means of the time effects in an example scenario. RESULTS: When a nearly flat prior for the time effects was used, the power or sample size calculated using the Bayesian approach matched the result obtained using the Frequentist approach with time effects included. When a highly precise prior for the time effects (with accurately specified prior means) was used, the Bayesian result matched the Frequentist result obtained with time effects excluded. When the prior means of the time effects were nearly correctly specified, including this information improved the efficiency of the trial with little bias introduced into the intervention effect estimate. When the prior means of the time effects were greatly mis-specified and a precise prior was used, this bias was substantial. CONCLUSION: Including prior information on time effects using a Bayesian approach may substantially reduce the required sample size. When the prior can be justified, results from applying this approach could support the conduct of a trial, which would be deemed infeasible if based on the larger sample size obtained using a Frequentist calculation. Caution is warranted as biased intervention effect estimates may arise when the prior distribution for the time effects is concentrated far from their true values.

Explaining the variation in the attained power of a stepped-wedge trial with unequal cluster sizes.

BACKGROUND: In a cross-sectional stepped-wedge trial with unequal cluster sizes, attained power in the trial depends on the realized allocation of the clusters. This attained power may differ from the expected power calculated using standard formulae by averaging the attained powers over all allocations the randomization algorithm can generate. We investigated the effect of design factors and allocation characteristics on attained power and developed models to predict attained power based on allocation characteristics. METHOD: Based on data simulated and analyzed using linear mixed-effects models, we evaluated the distribution of attained powers under different scenarios with varying intraclass correlation coefficient (ICC) of the responses, coefficient of variation (CV) of the cluster sizes, number of cluster-size groups, distributions of group sizes, and number of clusters. We explored the relationship between attained power and two allocation characteristics: the individual-level correlation between treatment status and time period, and the absolute treatment group imbalance. When computational time was excessive due to a scenario having a large number of possible allocations, we developed regression models to predict attained power using the treatment-vs-time period correlation and absolute treatment group imbalance as predictors. RESULTS: The risk of attained power falling more than 5% below the expected or nominal power decreased as the ICC or number of clusters increased and as the CV decreased. Attained power was strongly affected by the treatment-vs-time period correlation. The absolute treatment group imbalance had much less impact on attained power. The attained power for any allocation was predicted accurately using a logistic regression model with the treatment-vs-time period correlation and the absolute treatment group imbalance as predictors. CONCLUSION: In a stepped-wedge trial with unequal cluster sizes, the risk that randomization yields an allocation with inadequate attained power depends on the ICC, the CV of the cluster sizes, and number of clusters. To reduce the computational burden of simulating attained power for allocations, the attained power can be predicted via regression modeling. Trial designers can reduce the risk of low attained power by restricting the randomization algorithm to avoid allocations with large treatment-vs-time period correlations.

Outcomes of Critically Ill Patients Who Have Serotype 5 Invasive Pneumococcal Disease.

PURPOSE: To determine whether invasive pneumococcal disease (IPD) due to serotype 5, which occurred as a local outbreak in 2006 to 2007, is associated with intensive care unit (ICU) admission, hospital mortality, or organ supports in those who are critically ill. MATERIALS AND METHODS: Retrospective review of patients who presented with IPD to 2 tertiary hospitals in Vancouver, Canada, from July 2004 to June 2007. We compared patient characteristics, interventions, and outcomes between patients who had serotype 5 and other serotypes using bivariate and multivariate analyses. RESULTS: A total of 149 patients had serotype 5 and 106 had nonserotype 5. Patients with serotype 5 were younger, had lower prevalence of comorbid diseases, and had higher rates of substance use than patients with nonserotype 5. There were no differences in chest tube placement for complications of pneumonia or in ICU admission. Frequency of necrotizing pneumonia and hospital mortality were lower in the serotype 5 group. For the 71 patients with IPD who were admitted to ICU, there was no difference in severity of illness, ICU length of stay, or ICU mortality between the groups. There was also no difference in organ supports except that the serotype 5 group was more likely to receive vasopressors. CONCLUSION: Serotype 5 in patients who have IPD is associated with no difference in ICU admission but with increased use of vasopressors and lower hospital mortality.

Lithium vs valproate in the maintenance treatment of bipolar I disorder: A post- hoc analysis of a randomized double-blind placebo-controlled trial.

OBJECTIVE: Lithium and valproate are commonly used either in monotherapy or in combination with atypical antipsychotics in maintenance treatment of bipolar I disorder; however, their comparative efficacy is not well understood. This study aimed to compare the efficacy of valproate and lithium on mood stability either in monotherapy or in combination with atypical antipsychotics. METHODS: We performed a post hoc analysis using data from a 52-week randomized double-blind, placebo-controlled trial, that recruited 159 patients with recently remitted mania during treatment with lithium or valproate and adjunctive atypical antipsychotic therapy. Patients were randomized to discontinue adjunctive atypical antipsychotic at 0, 24 or 52 weeks. RESULTS: No significant differences in efficacy were observed between valproate and lithium (hazard ratio: 0.99; 95% confidence interval: [0.66, 1.48]) in time to any mood event. Valproate with 24 weeks of atypical antipsychotic was significantly superior to valproate monotherapy in preventing any mood relapse (hazard ratio: 0.46; 95% confidence interval: [0.22, 0.97]) while lithium with 24 weeks of atypical antipsychotic was superior to lithium monotherapy in preventing mania (hazard ratio: 0.27; 95% confidence interval: [0.09, 0.85]) but not depression. CONCLUSION: Overall, this study did not find significant differences in efficacy between the two mood-stabilizing agents when used as monotherapy or in combination with atypical antipsychotics. However, study design and small sample size might have precluded from detecting an effect if true difference in efficacy existed. Further head-to-head investigations with stratified designs are needed to evaluate maintenance therapies.

Specific manifestations of knee osteoarthritis predict depression and anxiety years in the future: Vancouver Longitudinal Study of Early Knee Osteoarthritis.

BACKGROUND: To evaluate whether knee osteoarthritis (OA) manifestations predict depression and anxiety using cross-sectional and longitudinal prediction models. METHODS: A population-based cohort (n = 122) with knee pain, aged 40-79, was evaluated at baseline, 3 and 7 years. Baseline predictors were: age decade; sex; BMI ≥ 25; physical exam knee effusion; crepitus; malalignment; quadriceps atrophy; flexion; flexion contracture; Kellgren-Lawrence (KL) x-ray grade (0/1/2/3+); WOMAC pain ≥25; WOMAC stiffness ≥25; self-reported knee swelling; and knee OA diagnosis (no/probable/definite). Depression and anxiety, cutoffs 5+ and 7+ respectively, were measured via the Hospital Anxiety and Depression Scale. We fit logistic models at each cycle using multivariable models selected via lowest Akaike's information criterion. RESULTS: Baseline depression model: sex (female OR = 0.27; 0.10, 0.76) and KL grade (KL 1 OR = 4.21; 1.31, 13.48). Three-year depression model: KL grade (KL 1 OR = 18.92; 1.73, 206.25). Seven-year depression model: WOMAC stiffness ≥25 (OR = 3.49; 1.02, 11.94) and flexion contracture ≥1 degree (OR = 0.23; 0.07, 0.81). Baseline anxiety model: knee swelling (OR = 4.11; 1.51, 11.13) and age (50-59 vs. 40-49 OR = 0.31 [0.11, 0.85]; 60-69 OR = 0.07 [0.01, 0.42]). Three-year anxiety model: WOMAC stiffness ≥25 (OR = 5.80; 1.23, 27.29) and KL grade (KL 1 OR = 6.25; 1.04, 37.65). Seven-year anxiety model: sex (female OR = 2.71; 0.87, 8.46). CONCLUSION: Specific knee OA-related manifestations predict depression and anxiety cross-sectionally, 3 years in the future, and for depression, 7 years in the future. This information may prove useful to clinicians in helping to identify patients most at risk of present or future depression and anxiety, thus facilitating preemptive discussions that may help counter that risk.

The impact of pediatric emergency department crowding on patient and health care system outcomes: a multicentre cohort study.

BACKGROUND: Emergency department overcrowding has been associated with increased odds of hospital admission and mortality after discharge from the emergency department in predominantly adult cohorts. The objective of this study was to evaluate the association between crowding and the odds of several adverse outcomes among children seen at a pediatric emergency department. METHODS: We conducted a retrospective cohort study involving all children visiting 8 Canadian pediatric emergency departments across 4 provinces between 2010 and 2014. We analyzed the association between mean departmental length of stay for each index visit and hospital admission within 7 days or death within 14 days of emergency department discharge, as well as hospital admission at index visit and return visits within 7 days, using mixed-effects logistic regression modelling. RESULTS: A total of 1 931 465 index visits occurred across study sites over the 5-year period, with little variation in index visit hospital admission or median length of stay. Hospital admission within 7 days of discharge and 14-day mortality were low across provinces (0.8%-1.5% and < 10 per 100 000 visits, respectively), and their association with mean departmental length of stay varied by triage categories and across sites but was not significant. There were increased odds of hospital admission at the index visit with increasing departmental crowding among visits triaged to Canadian Triage and Acuity Scale (CTAS) score 1-2 (odds ratios [ORs] ranged from 1.01 to 1.08) and return visits among patients with a CTAS score of 4-5 discharged at the index visit at some sites (ORs ranged from 1.00 to 1.06). INTERPRETATION: Emergency department crowding was not significantly associated with hospital admission within 7 days of the emergency department visit or mortality in children. However, it was associated with increased hospital admission at the index visit for the sickest children, and with return visits to the emergency department for those less sick.

A mechanistic nonlinear model for censored and mismeasured covariates in longitudinal models, with application in AIDS studies.

When modeling longitudinal data, the true values of time-varying covariates may be unknown because of detection-limit censoring or measurement error. A common approach in the literature is to empirically model the covariate process based on observed data and then predict the censored values or mismeasured values based on this empirical model. Such an empirical model can be misleading, especially for censored values since the (unobserved) censored values may behave very differently than observed values due to the underlying data-generation mechanisms or disease status. In this paper, we propose a mechanistic nonlinear covariate model based on the underlying data-generation mechanisms to address censored values and mismeasured values. Such a mechanistic model is based on solid scientific or biological arguments, so the predicted censored or mismeasured values are more reasonable. We use a Monte Carlo EM algorithm for likelihood inference and apply the methods to an AIDS dataset, where viral load is censored by a lower detection limit. Simulation results confirm that the proposed models and methods offer substantial advantages over existing empirical covariate models for censored and mismeasured covariates.

Gains of Continuing Resuscitation in Refractory Out-of-hospital Cardiac Arrest: A Model-based Analysis to Identify Deaths Due to Intra-arrest Prognostication.

OBJECTIVE: Prognostication bias, in which a clinician predicts a negative outcome and terminates resuscitation (TR) thereby ensuring a poor outcome, is a rarely identified limitation of out-of-hospital cardiac arrest (OHCA) research. We sought to estimate the number of deaths due to intra-arrest prognostication in a cohort of OHCA's, and use this data to estimate the incremental benefit of continuing resuscitation. METHODS: This study examined a cohort of consecutive non-traumatic EMS-treated OHCAs from a provincial ambulance service, between 2007 and 2011 inclusive. We used Cox and logistic regression modeling, adjusting for Utstein covariates, to estimate the probability of ROSC, survival, and favorable neurological outcomes as a function of resuscitation time, and applied these models to estimate the number of missed survivors in those who had TR (prior to 20, 30, or 40 minutes). We determined the time juncture at which (1) the likelihood of survival fell below 1%, and (2) the proportion of survivors who had achieved ROSC exceeded 99%. RESULTS: Of 5674 adult EMS-treated cases, 46% achieved ROSC, and 12% survived. The median time of TR was 27.0 minutes (IQR 19.0-35.0). Continuing resuscitation until 40 minutes yielded an estimated 17 additional survivors (95% CI 13-21), 10 (95% CI 7-13) with favorable neurological outcomes. The probability of survival of those in refractory arrest decreased below 1% at 28 minutes (95% CI 24-30 minutes). At 36 minutes (95% CI 34-38 minutes) >99% of survivors had achieved ROSC. CONCLUSION: We identified possible deaths due to intra-arrest prognostication. Resuscitation should be continued for a minimum of 30 minutes in all patients, however for those with initial shockable rhythms 40 minutes appears to be warranted. Interventional trials and observational studies should standardize or adjust for duration of resuscitation prior to TR.

Is the Road to Mental Health Paved With Good Incentives? Estimating the Population Impact of Physician Incentives on Mental Health Care Using Linked Administrative Data.

OBJECTIVES: The use of physician incentives to improve health care, in general, has been extensively studied but its value in mental health care has rarely been demonstrated. In this study the population-level impact of physician incentives on mental health care was estimated using indicators for receipt of counseling/psychotherapy (CP); antidepressant therapy (AT); minimally adequate counseling/psychotherapy; and minimally adequate antidepressant therapy. The incentives' impacts on overall continuity of care and of mental health care were also examined. MATERIALS AND METHODS: Monthly cohorts of individuals diagnosed with major depression were identified between January 2005 and December 2012 and their use of mental health services tracked for 12 months following initial diagnosis. Linked health administrative data were used to ascertain cases and measure health service use. Pre-post changes associated with the introduction of physician incentives were estimated using segmented regression analyses, after adjusting for seasonal variation. RESULTS: Physician incentives reversed the downward and upward trends in CP and AT. Five years postintervention, the estimated impacts in percentage points for CP, AT, minimally adequate counseling/psychotherapy, and minimally adequate antidepressant therapy were +3.28 [95% confidence interval (CI), 2.05-4.52], -4.47 (95% CI, -6.06 to -2.87), +1.77 (95% CI, 0.94-2.59), and -2.24 (95% CI, -4.04 to -0.45). Postintervention, the downward trends in continuity of care failed to reverse, but were disrupted, netting estimated impacts of +7.53 (95% CI, 4.54-10.53) and +4.37 (95% CI, 2.64-6.09) for continuity of care and of mental health care. CONCLUSIONS: The impact of physician incentives on mental health care was modest at best. Other policy interventions are needed to close existing gaps in mental health care.

A Practical ANOVA Approach for Uncertainty Analysis in Population-Based Disease Microsimulation Models.

OBJECTIVES: To provide a practical approach for calculating uncertainty intervals and variance components associated with initial-condition and dynamic-equation parameters in computationally expensive population-based disease microsimulation models. METHODS: In the proposed uncertainty analysis approach, we calculated the required computational time and the number of runs given a user-defined error bound on the variance of the grand mean. The equations for optimal sample sizes were derived by minimizing the variance of the grand mean using initial estimates for variance components. Finally, analysis of variance estimators were used to calculate unbiased variance estimates. RESULTS: To illustrate the proposed approach, we performed uncertainty analysis to estimate the uncertainty associated with total direct cost of osteoarthritis in Canada from 2010 to 2031 according to a previously published population health microsimulation model of osteoarthritis. We first calculated crude estimates for initial-population sampling and dynamic-equation parameters uncertainty by performing a small number of runs. We then calculated the optimal sample sizes and finally derived 95% uncertainty intervals of the total cost and unbiased estimates for variance components. According to our results, the contribution of dynamic-equation parameter uncertainty to the overall variance was higher than that of initial parameter sampling uncertainty throughout the study period. CONCLUSIONS: The proposed analysis of variance approach provides the uncertainty intervals for the mean outcome in addition to unbiased estimates for each source of uncertainty. The contributions of each source of uncertainty can then be compared with each other for validation purposes so as to improve the model accuracy.