A theory of consciousness from a theoretical computer science perspective: Insights from the Conscious Turing Machine.

This paper examines consciousness from the perspective of theoretical computer science (TCS), a branch of mathematics concerned with understanding the underlying principles of computation and complexity, including the implications and surprising consequences of resource limitations. We propose a formal TCS model, the Conscious Turing Machine (CTM). The CTM is influenced by Alan Turing's simple yet powerful model of computation, the Turing machine (TM), and by the global workspace theory (GWT) of consciousness originated by cognitive neuroscientist Bernard Baars and further developed by him, Stanislas Dehaene, Jean-Pierre Changeux, George Mashour, and others. Phenomena generally associated with consciousness, such as blindsight, inattentional blindness, change blindness, dream creation, and free will, are considered. Explanations derived from the model draw confirmation from consistencies at a high level, well above the level of neurons, with the cognitive neuroscience literature.

Biomarker, Imaging, and Clinical Factors Associated With Overt and Covert Stroke in Patients With Atrial Fibrillation.

BACKGROUND: Atrial fibrillation is a major risk factor for stroke and silent brain infarcts. We studied whether a multimodal approach offers additional insights to the CHA2DS2-VASc score in predicting stroke or new brain infarcts on magnetic resonance imaging (MRI) over a 2-year follow-up. METHODS: Swiss-AF is a prospective, multicenter cohort study of patients with known atrial fibrillation. We included patients with available brain MRI both at enrollment and 2 years later. The dates of the baseline and follow-up visits ranged from March 2014 to November 2020. The primary outcome was assessed 2 years after baseline and was defined as a composite of clinically identified stroke or any new brain infarct on the 2-year MRI. We compared a multivariable logistic regression model including prespecified clinical, biomarker, and baseline MRI variables to the CHA2DS2-VASc score. RESULTS: We included 1232 patients, 89.8% of them taking oral anticoagulants. The primary outcome occurred in 78 patients (6.3%). The following baseline variables were included in the final multivariate model and were significantly associated with the primary outcome: white matter lesion volume in milliliters (adjusted odds ratio [aOR], 1.91 [95% CI, 1.45-2.56]), NT-proBNP (N-terminal pro-B-type natriuretic peptide; aOR, 1.75 [95% CI, 1.20-2.63]), GDF-15 (growth differentiation factor-15; aOR, 1.68 [95% CI, 1.11-2.53]), serum creatinine (aOR, 1.50 [95% CI, 1.02-2.22]), IL (interleukin)-6 (aOR, 1.37 [95% CI, 1.00-1.86]), and hFABP (heart-type fatty acid-binding protein; aOR, 0.48 [95% CI, 0.31-0.73]). Overall performance and discrimination of the new model was superior to that of the CHA2DS2-VASc score (C statistic, 0.82 [95% CI, 0.77-0.87] versus 0.64 [95% CI, 0.58-0.70]). CONCLUSIONS: In patients with atrial fibrillation, a model incorporating white matter lesion volume on baseline MRI and selected blood markers yielded new insights on residual stroke risk despite a high proportion of patients on oral anticoagulants. This may be relevant to develop further preventive measures.

Do quantitative levels of antispike-IgG antibodies aid in predicting protection from SARS-CoV-2 infection? Results from a longitudinal study in a police cohort.

In a COVID-19 sero-surveillance cohort study with predominantly healthy and vaccinated individuals, the objectives were (i) to investigate longitudinally the factors associated with the quantitative dynamics of antispike (anti-S1) IgG antibody levels, (ii) to evaluate whether the levels were associated with protection from SARS-CoV-2 infection, and (iii) to assess whether the association was different in the pre-Omicron compared with the Omicron period. The QuantiVac Euroimmun ELISA test was used to quantify anti-S1 IgG levels. The entire study period (16 months), the 11-month pre-Omicron period and the cross-sectional analysis before the Omicron surge included 3219, 2310, and 895 reactive serum samples from 949, 919, and 895 individuals, respectively. Mixed-effect linear, mixed-effect time-to-event, and logistic regression models were used to achieve the objectives. Age and time since infection or vaccination were the only factors associated with a decline of anti-S1 IgG levels. Higher antibody levels were significantly associated with protection from SARS-CoV-2 infection (0.89, 95% confidence interval [CI] 0.82-0.97), and the association was higher during the time period when Omicron was predominantly circulating compared with the ones when Alpha and Delta variants were predominant (adjusted hazard ratio for interaction 0.66, 95% CI 0.53-0.84). In a prediction model, it was estimated that >8000 BAU/mL anti-S1 IgG was required to reduce the risk of infection with Omicron variants by approximately 20%-30% for 90 days. Though, such high levels were only found in 1.9% of the samples before the Omicron surge, and they were not durable for 3 months. Anti-S1 IgG antibody levels are statistically associated with protection from SARS-CoV-2 infection. However, the prediction impact of the antibody level findings on infection protection is limited.

Real-World Cost-Effectiveness of Pulmonary Vein Isolation for Atrial Fibrillation: A Target Trial Approach.

OBJECTIVES: Randomized controlled trials of pulmonary vein isolation (PVI) for treating atrial fibrillation (AF) have proven the procedure's efficacy. Studies assessing its empirical cost-effectiveness outside randomized trial settings are lacking. We aimed to evaluate the effectiveness and cost-effectiveness of PVI versus medical therapy for AF. METHODS: We followed a target trial approach using the Swiss-AF cohort, a prospective observational cohort study that enrolled patients with AF between 2014 and 2017. Resource utilization and cost information were collected through claims data. Quality of life was measured with EQ-5D-3L utilities. We estimated incremental cost-effectiveness ratios (ICERs) from the perspective of the Swiss statutory health insurance system. RESULTS: Patients undergoing PVI compared with medical therapy had a 5-year overall survival advantage with a hazard ratio of 0.75 (95% CI 0.46-1.21; P = .69) and a 19.8% SD improvement in quality of life (95% CI 15.5-22.9; P < .001), at an incremental cost of 29 604 Swiss francs (CHF) (95% CI 16 354-42 855; P < .001). The estimated ICER was CHF 158 612 per quality-adjusted life-year (QALY) gained within a 5-year time horizon. Assuming similar health effects and costs over 5 additional years changed the ICER to CHF 82 195 per QALY gained. Results were robust to the sensitivity analyses performed. CONCLUSIONS: Our results show that PVI might be a cost-effective intervention within the Swiss healthcare context in a 10-year time horizon, but unlikely to be so at 5 years, if a willingness-to-pay threshold of CHF 100 000 per QALY gained is assumed. Given data availability, we find target trial designs are a valuable tool for assessing the cost-effectiveness of healthcare interventions outside of randomized controlled trial settings.

Trueperella pyogenes endocarditis in a Swiss farmer: a case report and review of the literature.

BACKGROUND: Trueperella pyogenes (T. pyogenes) is a bacterium that colonizes the skin and mucosal surfaces of various domestic and wild animals. It rarely leads to infections in humans, with only a few descriptions available in the literature. CASE PRESENTATION: A 71-year-old Swiss farmer with a history of recurring basal cell carcinoma and metastasized pancreatic neuroendocrine tumor presented with signs of sepsis after a three-day history of general weakness, malaise and fever. Clinical and echocardiographic findings, as well as persistent bacteremia were consistent with mitral valve endocarditis caused by T. pyogenes. The patient's condition gradually improved under antibiotic treatment with piperacillin/tazobactam (empiric therapy of sepsis), and later penicillin G based on resistance testing. He was discharged after 13 days and continued outpatient antibiotic therapy with ceftriaxone, resulting in a total antibiotic treatment duration of six weeks. This is the first literature review of T. pyogenes endocarditis in humans. Among nine cases of T. pyogenes endocarditis, three patients had documented contact with farm animals and five had an underlying condition that compromised the immune system. While antibiotic resistance of T. pyogenes is an emerging concern, susceptibility to beta-lactam antibiotics seems to persist. The mortality of T. pyogenes endocarditis described in the literature was high, with 66% of patients not surviving the disease. CONCLUSIONS: T. pyogenes is a rare causative organism of infectious endocarditis in humans and descriptions are mainly restricted to case reports. In our review of the literature, we found that both an impaired immune system and contact with farm animals might be risk factors. Growth of T. pyogenes in blood cultures is unlikely to be missed during routine analysis, as it shows marked beta-hemolysis on blood agar culture plates, which generally leads to further characterization of the bacteria. Susceptibility to penicillin, ceftriaxone, and macrolides seems to be retained and the reported mortality in the few patients with T. pyogenes endocarditis is high.

Adjunct prednisone in community-acquired pneumonia: 180-day outcome of a multicentre, double-blind, randomized, placebo-controlled trial.

BACKGROUND: Several trials and meta-analyses found a benefit of adjunct corticosteroids for community-acquired pneumonia with respect to short-term outcome, but there is uncertainty about longer-term health effects. Herein, we evaluated clinical outcomes at long term in patients participating in the STEP trial (Corticosteroid Treatment for Community-Acquired Pneumonia). METHODS: This predefined secondary analysis investigated 180-day outcomes in 785 adult patients hospitalized with community-acquired pneumonia included in STEP, a randomised, placebo-controlled, double-blind trial. The primary endpoint was time to death from any cause at 180 days verified by telephone interview. Additional secondary endpoints included pneumonia-related death, readmission, recurrent pneumonia, secondary infections, new hypertension, and new insulin dependence. RESULTS: From the originally included 785 patients, 727 were available for intention-to-treat analysis at day 180. There was no difference between groups with respect to time to death from any cause (HR for corticosteroid use 1.15, 95% CI 0.68 to 1.95, p = 0.601). Compared to placebo, corticosteroid-treated patients had significantly higher risks for recurrent pneumonia (OR 2.57, 95% CI 1.29 to 5.12, p = 0.007), secondary infections (OR 1.94, 95% CI 1.25 to 3.03, p = 0.003) and new insulin dependence (OR 8.73, 95% CI 1.10 to 69.62, p = 0.041). There was no difference regarding pneumonia-related death, readmission and new hypertension. CONCLUSIONS: In patients with community-acquired pneumonia, corticosteroid use was associated with an increased risk for recurrent pneumonia, secondary infections and new insulin dependence at 180 days. Currently, it is uncertain whether these long-term adverse effects outweigh the short-term effects of corticosteroids in moderate CAP. TRIAL REGISTRATION: This trial was registered with ClinicalTrials. gov, number NCT00973154 before the recruitment of the first patient. First posted: September 9, 2009. Last update posted: April 21, 2015.

The complexity of human computation via a concrete model with an application to passwords.

What can humans compute in their heads? We are thinking of a variety of cryptographic protocols, games like sudoku, crossword puzzles, speed chess, and so on. For example, can a person compute a function in his or her head so that an eavesdropper with a powerful computer-who sees the responses to random inputs-still cannot infer responses to new inputs? To address such questions, we propose a rigorous model of human computation and associated measures of complexity. We apply the model and measures first and foremost to the problem of 1) humanly computable password generation and then, consider related problems of 2) humanly computable "one-way functions" and 3) humanly computable "pseudorandom generators." The theory of human computability developed here plays by different rules than standard computability; the polynomial vs. exponential time divide of modern computability theory is irrelevant to human computation. In human computability, the step counts for both humans and computers must be more concrete. As an application and running example, password generation schemas are humanly computable algorithms based on private keys. Humanly computable and/or humanly usable mean, roughly speaking, that any human needing-and capable of using-passwords can if sufficiently motivated generate and memorize a secret key in less than 1 h (including all rehearsals) and can subsequently use schema plus key to transform website names (challenges) into passwords (responses) in less than 1 min. Moreover, the schemas have precisely defined measures of security against all adversaries, human and/or machine.

[Internal differential diagnoses in acute back pain : An internal perspective on the possible causes of acute back pain]. / Internistische Differenzialdiagnosen bei akuten Rückenschmerzen : Eine internistische Perspektive zu den möglichen Ursachen von akuten Rückenschmerzen.

The majority of patients with acute back pain have no serious underlying disease; however, many internal diseases can be manifested as acute or chronic back pain. Therefore, in the assessment of patients with back pain the clinical history and clinical examination are important in order to detect indications for a possible underlying disease. Particularly red flags that indicate an acute or life-threatening disease should not be missed. In most cases where such red flags, risk factors or clinical indications are not present, no systematic search for internal underlying diseases is necessary. This article summarizes the most relevant differential diagnoses and clinical indications as well as warning symptoms.

Thyroid antibodies and levothyroxine effects in subclinical hypothyroidism: A pooled analysis of two randomized controlled trials.

BACKGROUND: Antithyroid antibodies increase the likelihood of developing overt hypothyroidism, but their clinical utility remains unclear. No large randomized controlled trial (RCT) has assessed whether older adults with subclinical hypothyroidism (SHypo) caused by autoimmune thyroid disease derive more benefits from levothyroxine treatment (LT4). OBJECTIVE: To determine whether older adults with SHypo and positive antibodies derive more clinical benefits from LT4 than those with negative antibodies. METHODS: We pooled individual participant data from two RCTs, Thyroid Hormone Replacement for Untreated Older Adults with Subclinical Hypothyroidism and IEMO 80+. Participants with persistent SHypo were randomly assigned to receive LT4 or placebo. We compared the effects of LT4 versus placebo in participants with and without anti-thyroid peroxidase (TPO) at baseline. The two primary outcomes were 1-year change in Hypothyroid Symptoms and Tiredness scores on the Thyroid-Related Quality-of-Life Patient-Reported Outcome Questionnaire. RESULTS: Among 660 participants (54% women) ≥65 years, 188 (28.5%) had positive anti-TPO. LT4 versus placebo on Hypothyroid Symptoms lead to an adjusted between-group difference of -2.07 (95% confidence interval: -6.04 to 1.90) for positive antibodies versus 0.89 (-1.76 to 3.54) for negative antibodies (p for interaction = 0.31). Similarly, there was no treatment effect modification by baseline antibody status for Tiredness scores-adjusted between-group difference 1.75 (-3.60 to 7.09) for positive antibodies versus 1.14 (-1.90 to 4.19) for negative antibodies (p for interaction = 0.98). Positive anti-TPO were not associated with better quality of life, improvement in handgrip strength, or fewer cardiovascular outcomes with levothyroxine treatment. CONCLUSIONS: Among older adults with SHypo, positive antithyroid antibodies are not associated with more benefits on clinical outcomes with LT4.

Prognostic factors, disease course, and treatment efficacy in Duchenne muscular dystrophy: A systematic review and meta-analysis.

INTRODUCTION/AIMS: Prognostic factors in Duchenne muscular dystrophy (DMD) predict the disease course and may help individualize patient care. The aim was to summarize the evidence on prognostic factors that may support treatment decisions. METHODS: We searched six databases for prospective studies that each included ≥50 DMD patients with a minimum follow-up of 1 y. Primary outcomes were age at loss of ambulation (LoA), pulmonary function (forced vital capacity percent of predicted, FVC%p), and heart failure. RESULTS: Out of 5074 references, 59 studies were analyzed. Corticosteroid use was associated with a delayed LoA (pooled effect hazard ratio [HR] 0.42, 95% confidence interval [CI] 0.23-0.75, I2 94%), better pulmonary function tests (higher peak FVC%, prolonged time with FVC%p > 50%, and reduced need for assisted ventilation) and delayed cardiomyopathy. Longer corticosteroid treatment was associated with later LoA (>1 y compared to <1 y; pooled HR: 0.50, 95% CI 0.27-0.90) and early treatment start (aged <5 y) may be associated with early cardiomyopathy and higher fracture risk. Genotype appeared to be an independent driver of LoA in some studies. Higher baseline physical function tests (e.g., 6-minute walk test) were associated with delayed LoA. Left ventricular dysfunction and FVC <1 L increased and the use of angiotensin-converting enzyme (ACE) inhibitors reduced the risk of heart failure and death. Fusion surgery in scoliosis may potentially preserve pulmonary function. DISCUSSION: Prognostic factors that may inform clinical decisions include age at corticosteroid treatment initiation and treatment duration, ACE-inhibitor use, baseline physical function tests, pulmonary function, and cardiac dysfunction.

The importance of intravenous immunoglobulin treatment in critically ill patients with necrotizing soft tissue infection: a retrospective cohort study.

BACKGROUND: Necrotizing soft-tissue infections are infections with high mortality. The use of immunoglobulins within a combination therapy including broad-spectrum antibiotics has been debated. We assessed potential benefits of immunoglobulins and hypothesized that they were associated with a treatment benefit in a high-resource setting. METHODS: Patients with necrotizing soft-tissue infection hospitalized in the tertiary intensive care unit of the University Hospital of Zurich, Switzerland, between 2008 and 2020 were included retrospectively. The association between immunoglobulin administration and in-hospital survival, intensive care unit length of stay, the incidences of acute renal failure, acute respiratory distress syndrome and septic shock were analyzed. RESULTS: After adjustment for confounders, no difference for in-hospital survival (hazard ratio 2.20, 95% confidence interval [CI] 0.24-20.20, p = 0.5), intensive care unit length of stay (subhazard ratio [SHR] 0.90, CI 0.41-1.98, p = 0.8) and the development of acute respiratory distress syndrome (SHR 1.2, CI 0.36-4.03, p = 0.77) was observed in patients with or without immunoglobulin treatment. The Simplified Acute Physiology Score II, the risk of developing acute renal failure (SHR 2.86, CI 1.33-6.15, p = 0.01) and septic shock (SHR 1.86, CI 1.02-3.40, p = 0.04) was higher in patients treated with immunoglobulins, possibly reflecting a higher disease severity beyond measured confounders. CONCLUSIONS: No clear evidence for a benefit of immunoglobulins in our cohort with consistent antibiotic use was found. Patients receiving immunoglobulins appeared more severely ill. Complementary to high treatment standards and appropriate antibiotics including beta lactams and protein synthesis inhibitors, immunoglobulins should be administered on a case-to-case basis, at least while more evidence from larger randomized controlled trials is missing.

[Should dyslipidemia be treated in the elderly and very old people?] / Faut-il traiter les dyslipidémies chez les personnes âgées et très âgées ?

The beneficial effect of statins on the risk of recurrence of cardiovascular disease (secondary prevention) is well demonstrated. In primary prevention (no symptomatic cardiovascular disease), the benefit of statins after the age of 70 years is less clear and elderly patients with comorbidities have often been excluded from large, randomized trials. Some ongoing clinical trials will provide more information on the potential benefits and risks of starting or stopping statins in older adults. In clinical practice, the decision to treat with statins needs to take into account age, comorbidities, life expectancy, functional and cognitive status and patient preferences (shared decision), but statin discontinuation is only recommended in the context of a clinical trial, as reviewed in this article.

L'effet bénéfique des statines sur le risque de récidive de maladie cardiovasculaire (prévention secondaire) est bien démontré. En prévention primaire (pas de maladie cardiovasculaire symptomatique), le bénéfice des statines après 70 ans est moins clair et les patients âgés avec des comorbidités ont souvent été exclus des grandes études randomisées. Des essais cliniques sont en cours et apporteront plus d'informations sur les potentiels effets bénéfiques et risques de débuter ou d'arrêter les statines chez les personnes âgées. Dans la pratique, en sus de l'âge, la décision de traiter par statine nécessite de prendre en compte les comorbidités, l'espérance de vie, l'état fonctionnel et cognitif et les souhaits du patient (décision partagée), mais un arrêt n'est recommandé que dans le cadre d'un essai clinique, comme revu dans cet article.

[Polypharmacy and inappropriate medications in multimorbid elderly patients - What OPERAM taught us and will teach us]. / Polypharmacie et medicaments inappropriés chez les patients âgés multimorbides - Ce que l'étude OPERAM nous apprend et va nous apprendre.

Polypharmacy and inappropriate medication use are very common in multimorbid older patients. This population has unfortunately been excluded from most large, randomized studies. In a recent multicenter randomized study (OPERAM), we included over 2000 multimorbid patients. We found that 86% of the patients aged 70 years and more had inappropriate medications and that these medications could be discontinued without negative impact on the health of these patients. This cohort of multimorbid patients will be followed for 10 years to evaluate their prognosis, life expectancy, treatments and quality of life, with numerous projects to better understand the inappropriate prescribing of individual drugs and their consequences on the health of this population.

La polypharmacie et les médicaments inappropriés sont très fréquents chez les patients âgés multimorbides. Cette population a malheureusement été exclue de la plupart des grandes études randomisées. Dans une récente étude randomisée multicentrique (OPERAM), nous avons inclus plus de 2000 patients multimorbides. Celle-ci a montré que 86 % des patients âgés de 70 ans et plus avaient des médicaments inappropriés et qu'il était possible de stopper leur administration, sans répercussion négative sur leur santé. Ces patients multimorbides constituent une cohorte qui va être suivie sur 10 ans pour évaluer leurs pronostic, espérance de vie, traitements et qualité de vie. Cela permettra la réalisation de nombreux projets, notamment pour mieux comprendre les conséquences de la prescription inappropriée de médicaments.

Cost-Effectiveness of Transitional Care Services After Hospitalization With Heart Failure.

Background: Patients with heart failure (HF) discharged from the hospital are at high risk for death and rehospitalization. Transitional care service interventions attempt to mitigate these risks. Objective: To assess the cost-effectiveness of 3 types of postdischarge HF transitional care services and standard care. Design: Decision analytic microsimulation model. Data Sources: Randomized controlled trials, clinical registries, cohort studies, Centers for Disease Control and Prevention life tables, Centers for Medicare & Medicaid Services data, and National Inpatient Sample (Healthcare Cost and Utilization Project) data. Target Population: Patients with HF who were aged 75 years at hospital discharge. Time Horizon: Lifetime. Perspective: Health care sector. Intervention: Disease management clinics, nurse home visits (NHVs), and nurse case management. Outcome Measures: Quality-adjusted life-years (QALYs), costs, net monetary benefits, and incremental cost-effectiveness ratios (ICERs). Results of Base-Case Analysis: All 3 transitional care interventions examined were more costly and effective than standard care, with NHVs dominating the other 2 interventions. Compared with standard care, NHVs increased QALYs (2.49 vs. 2.25) and costs ($81 327 vs. $76 705), resulting in an ICER of $19 570 per QALY gained. Results of Sensitivity Analysis: Results were largely insensitive to variations in in-hospital mortality, age at baseline, or costs of rehospitalization. Probabilistic sensitivity analysis confirmed that transitional care services were preferred over standard care in nearly all 10 000 samples, at willingness-to-pay thresholds of $50 000 or more per QALY gained. Limitation: Transitional care service designs and implementations are heterogeneous, leading to uncertainty about intervention effectiveness and costs when applied in particular settings. Conclusion: In older patients with HF, transitional care services are economically attractive, with NHVs being the most cost-effective strategy in many situations. Transitional care services should become the standard of care for postdischarge management of patients with HF. Primary Funding Source: Swiss National Science Foundation, Research Council of Norway, and an Intermountain-Stanford collaboration.

Thyroid Hormone Therapy for Older Adults with Subclinical Hypothyroidism.

BACKGROUND: The use of levothyroxine to treat subclinical hypothyroidism is controversial. We aimed to determine whether levothyroxine provided clinical benefits in older persons with this condition. METHODS: We conducted a double-blind, randomized, placebo-controlled, parallel-group trial involving 737 adults who were at least 65 years of age and who had persisting subclinical hypothyroidism (thyrotropin level, 4.60 to 19.99 mIU per liter; free thyroxine level within the reference range). A total of 368 patients were assigned to receive levothyroxine (at a starting dose of 50 µg daily, or 25 µg if the body weight was <50 kg or the patient had coronary heart disease), with dose adjustment according to the thyrotropin level; 369 patients were assigned to receive placebo with mock dose adjustment. The two primary outcomes were the change in the Hypothyroid Symptoms score and Tiredness score on a thyroid-related quality-of-life questionnaire at 1 year (range of each scale is 0 to 100, with higher scores indicating more symptoms or tiredness, respectively; minimum clinically important difference, 9 points). RESULTS: The mean age of the patients was 74.4 years, and 396 patients (53.7%) were women. The mean (±SD) thyrotropin level was 6.40±2.01 mIU per liter at baseline; at 1 year, this level had decreased to 5.48 mIU per liter in the placebo group, as compared with 3.63 mIU per liter in the levothyroxine group (P<0.001), at a median dose of 50 µg. We found no differences in the mean change at 1 year in the Hypothyroid Symptoms score (0.2±15.3 in the placebo group and 0.2±14.4 in the levothyroxine group; between-group difference, 0.0; 95% confidence interval [CI], -2.0 to 2.1) or the Tiredness score (3.2±17.7 and 3.8±18.4, respectively; between-group difference, 0.4; 95% CI, -2.1 to 2.9). No beneficial effects of levothyroxine were seen on secondary-outcome measures. There was no significant excess of serious adverse events prespecified as being of special interest. CONCLUSIONS: Levothyroxine provided no apparent benefits in older persons with subclinical hypothyroidism. (Funded by European Union FP7 and others; TRUST ClinicalTrials.gov number, NCT01660126 .).

Limitations and Misinterpretations of E-Values for Sensitivity Analyses of Observational Studies.

The E-value was recently introduced on the basis of earlier work as "the minimum strength of association…that an unmeasured confounder would need to have with both the treatment and the outcome to fully explain away a specific treatment-outcome association, conditional on the measured covariates." E-values have been proposed for wide application in observational studies evaluating causality. However, they have limitations and are prone to misinterpretation. E-values have a monotonic, almost linear relationship with effect estimates and thus offer no additional information beyond what effect estimates can convey. Whereas effect estimates are based on real data, E-values may make unrealistic assumptions. No general rule can exist about what is a "small enough" E-value, and users of the biomedical literature are not familiar with how to interpret a range of E-values. Problems arise for any measure dependent on effect estimates and their CIs-for example, bias due to selective reporting and dependence on choice of exposure contrast and level of confidence. The automation of E-values may give an excuse not to think seriously about confounding. Moreover, biases other than confounding may still undermine results. Instead of misused or misinterpreted E-values, the authors recommend judicious use of existing methods for sensitivity analyses with careful assumptions; systematic assessments of whether and how known confounders have been handled, along with consideration of their prevalence and magnitude; thorough discussion of the potential for unknown confounders considering the study design and field of application; and explicit caution in making causal claims from observational studies.

Cosyntropin testing does not predict response to glucocorticoids in community-acquired pneumonia in a randomized controlled trial.

OBJECTIVE: Glucocorticoids have been shown to improve outcome in community-acquired pneumonia (CAP). However, glucocorticoids have potential side-effects, and treatment response may vary. It is thus crucial to select patients with high likelihood to respond favourably. In critical illness, cosyntropin testing is recommended to identify patients in need for glucocorticoids. We investigated whether cosyntropin testing predicts treatment response to glucocorticoids in CAP. DESIGN: Predefined secondary analysis of a randomized controlled trial. PATIENTS: Hospitalized patients with CAP. MEASUREMENTS: We performed 1 µg cosyntropin tests in a randomized trial comparing prednisone 50 mg for 7 days to placebo. We investigated whether subgroups based on baseline and stimulated cortisol levels responded differently to glucocorticoids with regard to time to clinical stability (TTCS) and other outcomes by inclusion of interaction terms into statistical models. RESULTS: A total of 326 patients in the prednisone and 309 patients in the placebo group were evaluated. Neither basal cortisol nor a Δcortisol <250 nmol/L after stimulation nor the combination of basal cortisol and Δcortisol predicted treatment response as measured by TTCS (all P for interaction >0.05). Similarly, we found no effect modification with respect to mortality, rehospitalization, antibiotic treatment duration or CAP-related complications (all P for interaction >0.05). However, glucocorticoids had a stronger effect on shortening length of hospital stay in patients with a baseline cortisol of ≥938 nmol/L (P for interaction = 0.015). CONCLUSIONS: Neither baseline nor stimulated cortisol after low-dose cosyntropin testing at a dose of 1 µg predicted glucocorticoid responsiveness in mild to moderate CAP. A treatment decision for or against adjunct glucocorticoids in CAP should not be made depending on cortisol values or cosyntropin testing results.

How does exercise treatment compare with antihypertensive medications? A network meta-analysis of 391 randomised controlled trials assessing exercise and medication effects on systolic blood pressure.

OBJECTIVE: To compare the effect of exercise regimens and medications on systolic blood pressure (SBP). DATA SOURCES: Medline (via PubMed) and the Cochrane Library. ELIGIBILITY CRITERIA: Randomised controlled trials (RCTs) of angiotensin-converting enzyme inhibitors (ACE-I), angiotensin-2 receptor blockers (ARBs), ß-blockers, calcium channel blockers (CCBs) and diuretics were identified from existing Cochrane reviews. A previously published meta-analysis of exercise interventions was updated to identify recent RCTs that tested the SBP-lowering effects of endurance, dynamic resistance, isometric resistance, and combined endurance and resistance exercise interventions (up to September 2018). DESIGN: Random-effects network meta-analysis. OUTCOME: Difference in mean change from baseline SBP between comparator treatments (change from baseline in one group minus that in the other group) and its 95% credible interval (95% CrI), measured in mmHg. RESULTS: We included a total of 391 RCTs, 197 of which evaluated exercise interventions (10 461 participants) and 194 evaluated antihypertensive medications (29 281 participants). No RCTs compared directly exercise against medications. While all medication trials included hypertensive populations, only 56 exercise trials included hypertensive participants (≥140 mmHg), corresponding to 3508 individuals. In a 10% random sample, risk of bias was higher in exercise RCTs, primarily due to lack of blinding and incomplete outcome data. In analyses that combined all populations, antihypertensive medications achieved higher reductions in baseline SBP compared with exercise interventions (mean difference -3.96 mmHg, 95% CrI -5.02 to -2.91). Compared with control, all types of exercise (including combination of endurance and resistance) and all classes of antihypertensive medications were effective in lowering baseline SBP. Among hypertensive populations, there were no detectable differences in the SBP-lowering effects of ACE-I, ARB, ß-blocker and diuretic medications when compared with endurance or dynamic resistance exercise. There was no detectable inconsistency between direct and indirect comparisons. Although there was evidence of small-study effects, this affected both medication and exercise trials. CONCLUSIONS: The effect of exercise interventions on SBP remains under-studied, especially among hypertensive populations. Our findings confirm modest but consistent reductions in SBP in many studied exercise interventions across all populations but individuals receiving medications generally achieved greater reductions than those following structured exercise regimens. Assuming equally reliable estimates, the SBP-lowering effect of exercise among hypertensive populations appears similar to that of commonly used antihypertensive medications. Generalisability of these findings to real-world clinical settings should be further evaluated.

Association Between Levothyroxine Treatment and Thyroid-Related Symptoms Among Adults Aged 80 Years and Older With Subclinical Hypothyroidism.

IMPORTANCE: It is unclear whether levothyroxine treatment provides clinically important benefits in adults aged 80 years and older with subclinical hypothyroidism. OBJECTIVE: To determine the association of levothyroxine treatment for subclinical hypothyroidism with thyroid-related quality of life in adults aged 80 years and older. DESIGN, SETTING, AND PARTICIPANTS: Prospectively planned combined analysis of data involving community-dwelling adults aged 80 years and older with subclinical hypothyroidism. Data from a randomized clinical trial were combined with a subgroup of participants aged 80 years and older from a second clinical trial. The trials were conducted between April 2013 and May 2018. Final follow-up was May 4, 2018. EXPOSURES: Participants were randomly assigned to receive levothyroxine (n = 112; 52 participants from the first trial and 60 from the second trial) or placebo (n = 139; 53 participants from the first trial and 86 from the second trial). MAIN OUTCOMES AND MEASURES: Co-primary outcomes were Thyroid-Related Quality of Life Patient-Reported Outcome (ThyPRO) questionnaire scores for the domains of hypothyroid symptoms and tiredness at 1 year (range, 0-100; higher scores indicate worse quality of life; minimal clinically important difference, 9). RESULTS: Of 251 participants (mean age, 85 years; 118 [47%] women), 105 were included from the first clinical trial and 146 were included from the second clinical trial. A total of 212 participants (84%) completed the study. The hypothyroid symptoms score decreased from 21.7 at baseline to 19.3 at 12 months in the levothyroxine group vs from 19.8 at baseline to 17.4 at 12 months in the placebo group (adjusted between-group difference, 1.3 [95% CI, -2.7 to 5.2]; P = .53). The tiredness score increased from 25.5 at baseline to 28.2 at 12 months in the levothyroxine group vs from 25.1 at baseline to 28.7 at 12 months in the placebo group (adjusted between-group difference, -0.1 [95% CI, -4.5 to 4.3]; P = .96). At least 1 adverse event occurred in 33 participants (29.5%) in the levothyroxine group (the most common adverse event was cerebrovascular accident, which occurred in 3 participants [2.2%]) and 40 participants (28.8%) in the placebo group (the most common adverse event was pneumonia, which occurred in 4 [3.6%] participants). CONCLUSIONS AND RELEVANCE: In this prospectively planned analysis of data from 2 clinical trials involving adults aged 80 years and older with subclinical hypothyroidism, treatment with levothyroxine, compared with placebo, was not significantly associated with improvement in hypothyroid symptoms or fatigue. These findings do not support routine use of levothyroxine for treatment of subclinical hypothyroidism in adults aged 80 years and older. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01660126; Netherlands Trial Register: NTR3851.

[Subclinical hypothyroidism : should we still treat elderly patients? Clinical implications of a new trial in primary care]. / Hypothyroïdie infraclinique : faut-il encore traiter les personnes âgées ? Implications cliniques d'une nouvelle étude en médecine de famille.

Subclinical hypothyroidism, defined as an elevated level of thyrotropin hormone (TSH) and normal thyroxin, is more frequent in women and above 65 years old. This condition is associated with an increased cardiovascular risk, in particular with TSH > 10,0 mIU/L. Although overt hypothyroidism is rare (prevalence of 0,3 %), levothyroxine has become the most prescribed medication in the US, while its indications are still debated. The European-funded TRUST trial showed no improvement in Hypothyroid Symptoms and Tiredness scores among patients ≥ 65 years with subclinical hypothyroidism treated with levothyroxine, and no improvement in blood pressure, weight, muscle strength and cognition. The results of this study call for a revision of the current international recommendations on the treatment of subclinical hypothyroidism.

L'hypothyroïdie infraclinique, soit un taux élevé d'hormone thyréotrope (TSH) et une thyroxine normale, est plus fréquente chez les femmes et après 65 ans. Cette condition est associée à une élévation du risque cardiovasculaire, en particulier lors de TSH > 10,0 mUl/l. Bien que l'hypothyroïdie franche soit peu fréquente (prévalence de 0,3 %), la lévothyroxine est devenue le médicament le plus prescrit aux Etats-Unis, alors que ses indications restent controversées. L'étude européenne TRUST a montré l'absence d'amélioration des scores de fatigue et d'hypothyroïdie chez des personnes âgées ≥ 65 ans avec hypothyroïdie infraclinique sous lévothyroxine, ainsi qu'une absence de bénéfice pour la tension artérielle, le poids, la force et la cognition. Nous proposons ici d'adapter les recommandations internationales sur l'hypothyroïdie infraclinique.