Look left, look right: censoring in clinical research

In this methodology editorial, the problem of censored survival (or time-to-event) data in clinical research is discussed. In case of censored observations, part of the observation time for some participants in a study is unobserved, which means that measures such as an average survival time cannot be calculated. Instead, censored survival time should explicitly be accounted for in the analysis of a study, for example using the Kaplan-Meier method. Implications of censoring and how to deal with it in the analysis of a study or when reading a research paper are discussed.

Comorbidities in mild autonomous cortisol secretion and the effect of treatment: systematic review and meta-analysis

OBJECTIVE

To assess (1) comorbidities associated with and (2) treatment strategies for patients with adrenal incidentalomas and mild autonomous cortisol secretion (MACS; > 1.8 µg/dL (>50 nmol/L) cortisol level cut-off following the 1 mg dexamethasone suppression test).

DESIGN

Systematic review and meta-analysis.

METHODS

Seven databases were searched up to July 14, 2022. Eligible studies were (randomized) trials, cohort studies, and cross-sectional studies assessing comorbidities potentially attributable to cortisol excess or mortality in patients with adrenal incidentaloma with or without MACS or the effects of conservative or surgical management of MACS. Random-effects meta-analysis was performed to estimate pooled proportions (with 95% CIs).

RESULTS

In 30 cross-sectional and 16 cohort studies (n = 17 156 patients in total), patients with MACS had a higher prevalence of diabetes (relative risk [RR] 1.44 [1.23-1.69]), hypertension (RR = 1.24 [1.16-1.32]), and dyslipidemia (RR = 1.23 [1.13-1.34]). All-cause mortality (adjusted for confounders) in patients with MACS, assessed in 4 studies (n = 5921), was increased (hazard ratio [HR] = 1.54 [1.27-1.81]). Nine observational studies (n = 856) and 2 randomized trials (n = 107) suggest an improvement in glucometabolic control (RR = 7.99 [2.95-21.90]), hypertension (RR = 8.75 [3.99-19.18]), and dyslipidemia (RR = 3.24 [1.19-8.82]) following adrenalectomy.

CONCLUSIONS

The present systematic review and meta-analysis highlight the relevance of MACS, since both cardiometabolic morbidities and mortality appeared to have increased in patients with MACS compared to patients with non-functioning incidentalomas. However, due to heterogeneous definitions, various outcomes, selective reporting, and missing data, the reported pooled estimates need to be interpreted with caution. The small number of patients in randomized trials prevents any strong conclusion on the causality between MACS and these comorbidities.

[Influenza vaccination as secondary prevention for cardiovascular disease]

Influenza infection increases the risk of cardiovascular complications and mortality in patients with heart disease. In patients with coronary artery disease influenza vaccination has been shown to reduce cardiovascular mortality, but high-quality evidence was missing. New trial data from a RCT in patients shortly after myocardial infarction has confirmed the significant reduction of the risk of major adverse cardiovascular events (MACE) and cardiovascular death after influenza vaccination. Also in patients with heart failure the first published RCT in heart failure shows a clinical benefit of influenza vaccination versus placebo during the influenza season, confirming preceding observational studies. Meta-analyses from the study data estimate that after influenza vaccination a risk reduction of MACE of at least 25% is possible in patients with heart disease. The current underutilization of influenza vaccines in heart patients should be addressed because influenza vaccination has proven to be an effective and safe instrument for secondary prevention.

Diagnostic and societal impact of implementing the syncope guidelines of the European Society of Cardiology (SYNERGY study)

BACKGROUND

Syncope management is fraught with unnecessary tests and frequent failure to establish a diagnosis. We evaluated the potential of implementing the 2018 European Society of Cardiology (ESC) Syncope Guidelines regarding diagnostic yield, accuracy and costs.

METHODS

A multicentre pre-post study in five Dutch hospitals comparing two groups of syncope patients visiting the emergency department: one before intervention (usual care; from March 2017 to February 2019) and one afterwards (from October 2017 to September 2019). The intervention consisted of the simultaneous implementation of the ESC Syncope Guidelines with quick referral routes to a syncope unit when indicated. The primary objective was to compare diagnostic accuracy using logistic regression analysis accounting for the study site. Secondary outcome measures included diagnostic yield, syncope-related healthcare and societal costs. One-year follow-up data were used to define a gold standard reference diagnosis by applying ESC criteria or, if not possible, evaluation by an expert committee. We determined the accuracy by comparing the treating physician's diagnosis with the reference diagnosis.

RESULTS

We included 521 patients (usual care, n = 275; syncope guidelines intervention, n = 246). The syncope guidelines intervention resulted in a higher diagnostic accuracy in the syncope guidelines group than in the usual care group (86% vs.69%; risk ratio 1.15; 95% CI 1.07 to 1.23) and a higher diagnostic yield (89% vs. 76%, 95% CI of the difference 6 to 19%). Syncope-related healthcare costs did not differ between the groups, yet the syncope guideline implementation resulted in lower total syncope-related societal costs compared to usual care (saving €908 per patient; 95% CI €34 to €1782).

CONCLUSIONS

ESC Syncope Guidelines implementation in the emergency department with quick referral routes to a syncope unit improved diagnostic yield and accuracy and lowered societal costs.

TRIAL REGISTRATION

Netherlands Trial Register, NTR6268.

[Challenges for evaluating complex interventions: The example of lifestyle]

Lifestyle interventions potentially contribute to the prevention and treatment of a number of common chronic diseases, such as type 2 diabetes and obesity. Nobody questions the importance of a healthy lifestyle, but at the same time it is clear that the effectiveness of lifestyle interventions has often not been investigated in a randomized controlled study, whereas the randomized clinical trial (RCT) is the golden standard in clinical drug research. In this article we discuss the methodological (im)possibilities of using RCTs in evaluating the effects of lifestyle interventions. We also explore the value of other research methods, especially carefully designed non-randomized clinical trials. Under the right conditions, non-randomized 'real world' research can provide valid evidence for the effectiveness and safety of lifestyle interventions.

Subgroup analyses in clinical research: too tempting?

In many biomedical studies, subgroup analyses are performed to identify subgroups of patients in whom a treatment is most effective, or a risk factor has the largest effect. While both are referred to as subgroup analysis, it is important to distinguish between estimation of effects within subgroups and comparison of effects across subgroups. Both are discussed and we outline the implications regarding sample size and statistical methods for estimation of effects. Also, the risk of false-positive findings - which potentially increases with subgroup analysis - is discussed, as well as the distinction between effect modification and interaction.

Diagnostic and therapeutic practices in adult chronic nonbacterial osteomyelitis (CNO)

BACKGROUND

Chronic nonbacterial osteomyelitis (CNO) is a rare, and impactful auto-inflammatory bone disease occurring in children and adults. Clinical care for CNO is challenging, as the condition lacks validated classification criteria and evidence-based therapies. This study aimed to map the current diagnostic and therapeutic practices for CNO in adults, as a first step towards a standardized disease definition and future consensus treatment plans.

METHODS

A primary survey was spread among global rheumatological/bone networks and 57 experts as identified from literature (May 2022), covering terminology, diagnostic tools (clinical, radiological, biochemical) and treatment steps. A secondary survey (sent to primary survey responders in August 2022) further queried key diagnostic features, treatment motivations, disease activity and treatment response monitoring.

RESULTS

36 and 23 physicians completed the primary and secondary survey respectively. Diagnosis was mainly based on individual physician assessment, in which the combination of chronic relapsing-remitting bone pain with radiologically-proven osteitis/osteomyelitis, sclerosis, hyperostosis and increased isotope uptake on bone scintigraphy were reported indicative of CNO. Physicians appeared more likely to refer to the condition as synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome in the presence of joint and skin pathology. MRI was most frequently performed, and the preferred diagnostic test for 47%. X-rays were second-most frequently used, although considered least informative of all available tools. Typical imaging features reported were hyperostosis, osteitis, osteosclerosis, bone marrow edema, while degeneration, soft tissue calcification, and ankylosis were not regarded characteristic. Inflammation markers and bone markers were generally regarded unhelpful for diagnostic and monitoring purposes and physicians infrequently performed bone biopsies. Management strategies diverged, including indications for treatment, response monitoring and declaration of remission. Step-1 treatment consisted of non-steroidal anti-inflammatory drugs/COX-2 inhibitors (83%). Common step 2-3 treatments were pamidronate, methotrexate, and TNF-a-inhibition (anti-TNFα), the latter two regarded especially convenient to co-target extra-skeletal inflammation in SAPHO syndrome. Overall pamidronate and anti-TNFα and were considered the most effective treatments.

CONCLUSIONS

Following from our survey data, adult CNO is a broad and insufficiently characterized disease spectrum, including extra-osseous features. MRI is the favoured imaging diagnostic, and management strategies vary significantly. Overall, pamidronate and anti-TNFα are regarded most successful. The results lay out current practices for adult CNO, which may serve as backbone for a future consensus clinical guideline.

Aggressive Pituitary Tumors and Pituitary Carcinomas: From Pathology to Treatment

Aggressive pituitary tumors (APTs) and pituitary carcinomas (PCs) are heterogeneous with regard to clinical presentation, proliferative markers, clinical course, and response to therapy. Half of them show an aggressive course only many years after the first apparently benign presentation. APTs and PCs share several properties, but a Ki67 index greater than or equal to 10% and extensive p53 expression are more prevalent in PCs. Mutations in TP53 and ATRX are the most common genetic alterations; their detection might be of value for early identification of aggressiveness. Treatment requires a multimodal approach including surgery, radiotherapy, and drugs. Temozolomide is the recommended first-line chemotherapy, with response rates of about 40%. Immune checkpoint inhibitors have emerged as second-line treatment in PCs, with currently no evidence for a superior effect of dual therapy compared to monotherapy with PD-1 blockers. Bevacizumab has resulted in partial response (PR) in few patients; tyrosine kinase inhibitors and everolimus have generally not been useful. The effect of peptide receptor radionuclide therapy is limited as well. Management of APT/PC is challenging and should be discussed within an expert team with consideration of clinical and pathological findings, age, and general condition of the patient. Considering that APT/PCs are rare, new therapies should preferably be evaluated in shared standardized protocols. Prognostic and predictive markers to guide treatment decisions are needed and are the scope of ongoing research.

European Society of Endocrinology Clinical Practice Guidelines on the management of adrenal incidentalomas, in collaboration with the European Network for the Study of Adrenal Tumors

Adrenal incidentalomas are adrenal masses detected on imaging performed for reasons other than suspected adrenal disease. In most cases, adrenal incidentalomas are non-functioning adrenocortical adenomas, but may also require therapeutic intervention including that for adrenocortical carcinoma, pheochromocytoma, hormone-producing adenoma or metastases. Here, we provide a revision of the first international, interdisciplinary guidelines on incidentalomas. We followed the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system and updated systematic reviews on four predefined clinical questions crucial for the management of incidentalomas: A) How to assess risk of malignancy? ; B) How to define and manage mild autonomous cortisol secretion? ; C) Who should have surgical treatment and how should it be performed? ; D) What follow-up is indicated if the adrenal incidentaloma is not surgically removed? Selected Recommendations: 1) Each adrenal mass requires dedicated adrenal imaging. Recent advances now allow discrimination between risk categories: Homogeneous lesions with HU ≤ 10 on unenhanced CT are benign and do not require any additional imaging independent of size. All other patients should be discussed in a multidisciplinary expert meeting, but only lesions >4 cm that are inhomogeneous or have HU >20 have sufficiently high risk of malignancy that surgery will be the usual management of choice. 2) Every patient needs a thorough clinical and endocrine work-up to exclude hormone excess including the measurement of plasma or urinary metanephrines and a 1-mg overnight dexamethasone suppression test (applying a cutoff value of serum cortisol ≤50 nmol/l (≤1.8 µg/dl)). Recent studies have provided evidence that most patients without clinical signs of overt Cushing's syndrome but serum cortisol levels post dexamethasone >50 nmol/l (>1.8 µg/dl) harbor increased risk of morbidity and mortality. For this condition, we propose the term 'mild autonomous cortisol secretion' (MACS). 3) All patients with MACS should be screened for potential cortisol-related comorbidities that are potentially attributably to cortisol (e.g. hypertension and type 2 diabetes mellitus), to ensure these are appropriately treated. 4) In patients with MACS who also have relevant comorbidities surgical treatment should be considered in an individualized approach. 5) The appropriateness of surgical intervention should be guided by the likelihood of malignancy, the presence and degree of hormone excess, age, general health and patient preference. We provide guidance on which surgical approach should be considered for adrenal masses with radiological findings suspicious of malignancy. 6) Surgery is not usually indicated in patients with an asymptomatic, non-functioning unilateral adrenal mass and obvious benign features on imaging studies. Furthermore, we offer recommendations for the follow-up of non-operated patients, management of patients with bilateral incidentalomas, for patients with extra-adrenal malignancy and adrenal masses, and for young and elderly patients with adrenal incidentalomas. Finally, we suggest ten important research questions for the future.

Tying research question and analytical strategy when variables are affected by medication use

Ill-defined research questions could be particularly problematic in an epidemiological setting where measurements fluctuate over time due to intercurrent events, such as medication use. When a research question fails to specify how medication use should be handled methodologically, arbitrary decisions may be made during the analysis phase, which likely leads to a mismatch between the intended question and the performed analysis. The mismatch can result in vastly different or meaningless interpretations of estimated effects. Thus, a research question such as "what is the effect of X on Y?" requires further elaboration, and it should consider whether and how medication use has affected the measurements of interest. In our study, we will discuss how well-defined questions can be formulated when medication use is involved in observational studies. We will distinguish between a situation where an exposure is affected by medication use and where the outcome of interest is affected by medication use. For each setting, we will give examples of different research questions that could be asked depending on how medication use is considered in the estimand and discuss methodological considerations under each question.

Effects of discontinuation of levothyroxine treatment in older adults: protocol for a self-controlled trial

BACKGROUND

Many older persons use the thyroid hormone levothyroxine which is often continued for life. Scientifically, there is much uncertainty whether simple continuation is the optimal approach. First, the physical need for levothyroxine can decrease with age thereby posing a higher risk of overtreatment and adverse effects. Second, large trials in subclinical hypothyroidism have shown no benefit for the use of levothyroxine. Interestingly, guidelines do not address re-evaluation of the indication. This self-controlled trial aims to determine the effects of discontinuation of levothyroxine treatment in older adults.

METHODS AND ANALYSIS

Participants are community-dwelling subjects aged ≥60 years using levothyroxine continuously at a stable dosage of ≤150 µg and a level of thyroid-stimulating hormone (TSH) <10 mU/L. After a control period of 12 weeks, levothyroxine treatment is discontinued gradually using a stepwise approach with regular monitoring of thyroid function guided by their GP. The primary outcome is the proportion of participants withdrawn from levothyroxine while maintaining a free T4 level within the reference range and a TSH level <10 mU/L, 52 weeks after the start of discontinuation. Secondary outcomes are compared with the control period (self-controlled) and include among others, the effects on thyroid-specific and general health-related quality of life. Furthermore, patients' attitudes towards deprescribing and regret regarding discontinuing levothyroxine treatment will be recorded. A total of 513 participants will be recruited to estimate the expected proportion of 50% with a 95% CI ranging from 45% to 55%.

ETHICS AND DISSEMINATION

Approval was obtained from the institutional Medical Ethics Committee. The Older People Advisory Board Health and Well-being has reviewed the research proposal and their comments were used for improvement. In line with the funding policies of the grant organisation funding this study, the study results will be proactively disseminated to the general public and key public health stakeholders.

TRIAL REGISTRATION NUMBER

NL7978; NCT05821881.

Initial pathology in aggressive pituitary tumours and carcinomas: 2b or not 2b?-that is the question

From a cohort of 171 patients comprising 121 aggressive pituitary tumours (APT) and 50 pituitary carcinomas (PC), the clinicopathological or five-tiered classification based on tumour invasion and proliferation evaluated by at least 2 proliferative markers over the cut-offs (Ki-67 ≥3% or ≥10%, p53 positive or expressed in %, mitotic count &gt;2%), could be applied on 43 tumours: 20 PC and 23 APT. At the initial surgery, 29/43 tumours (67.4%) were grade 2b (invasive and proliferative) of which 44.8% developed metastases during follow-up (PC, grade 3). Out of these 29 tumours, 55.1% had a Ki-67 ≥10%, and were classified grade 2b* (invasive and highly proliferative). There was one tumour grade 1b* (non-invasive and highly proliferative) which metastazed. Out of the 43 tumours, 30.2 % were grade 2a (invasive and non-proliferative). The sensitivity and the specificity of grade 2b for the diagnosis of APT at the initial surgery, were 68% and 90% respectively. The comparison of the high percentage (67.4%) of grade 2b tumours in this selected cohort of APT/PC with the low percentage (8.8%) in a surgical cohort of unselected tumours shows that the initial pathological diagnosis of grade 2b tumour may be considered, in the clinic, as representing a diagnosis of APT. In addition, a significant subgroup of tumours, which will develop metastases supports the proposal that an aggressive grade 2b tumour is “a tumour with malignant potential” or “a malignant tumour without metastases”. So, the clinician may take into account the pathological diagnosis, at the initial surgery, to propose a strict follow-up and to consider earlier use of radiotherapy and/or of temozolomide in the presence of tumours with aggressive behaviour.

Trends in incidence and mortality risk for acromegaly in Norway: a cohort study

PURPOSE

Recent data have shown a decreasing overall mortality in acromegaly over the last decades. However, cancer incidence and cancer-related mortality still appear to be increased. Our aim was to obtain updated epidemiological data from Norway in a clinically well-defined cohort with complete register-based follow-up.

METHODS

Patients diagnosed with acromegaly from South-Eastern Norway between 1999-2019 (n = 262) and age and sex matched population controls (1:100) were included (n = 26,200). Mortality and cancer data were obtained from the Norwegian Cause of Death and Cancer Registry. Mortality and cancer incidence were compared by Kaplan-Meier analyses and Cox regression; we report hazard ratios (HRs) with 95% confidence intervals (95% CI).

RESULTS

Median age at diagnosis was 48.0 years (interquartile range (IQR): 37.6-58.0). Mean annual acromegaly incidence rate was 4.7 (95% CI 4.2-5.3) cases/10⁶ person-years, and the point prevalence (2019) was 83 (95% CI 72.6-93.5) cases/10⁶ persons. Overall mortality was not increased in acromegaly, HR 0.8 (95% CI 0.5-1.4), cancer-specific and cardiovascular-specific mortality was also not increased (HR: 0.7 (95% CI 0.3-1.8) and 0.8 (95% CI: 0.3-2.5) respectively). The HR for all cancers was 1.45 (1.0-2.1; p = 0.052).

CONCLUSION

In this large cohort study, covering the period 1999-2019, patients were treated with individualized multimodal management. Mortality was not increased compared to the general population and comparable with recent registry studies from the Nordic countries and Europe. Overall cancer risk was slightly, but not significantly increased in the patients.

Breast cancer, breast cancer-directed radiation therapy and risk of hypothyroidism: A systematic review and meta-analysis

OBJECTIVE

Breast cancer and breast cancer-directed radiation therapy (RT) may increase the risk of late effects, such as hypothyroidism. We conducted a systematic review and meta-analysis to investigate the association between breast cancer, RT, and risk of hypothyroidism in breast cancer survivors.

METHODS

Through February 2022, we searched PubMed, EMBASE, and references of relevant articles, to identify papers on breast cancer and breast cancer-directed RT and subsequent risk of hypothyroidism. Articles were screened by title and abstract and reviewed for eligibility. We used a pre-formed data extraction sheet and identified key design elements that could potentially introduce bias. The main outcome was the confounder-adjusted relative risk (RR) of hypothyroidism in breast cancer survivors versus women without breast cancer, and in breast cancer survivors according to the receipt of RT to the supraclavicular lymph nodes. We used a random-effects model to calculate pooled RRs and associated 95% confidence intervals (95% CI).

RESULTS

From 951 papers screened by title and abstract, 34 full-text papers were reviewed for eligibility. We included 20 studies published between 1985 and 2021-19 were cohort studies. Compared with women without breast cancer, the pooled RR of hypothyroidism in breast cancer survivors was 1.48 (95% CI: 1.17, 1.87), with highest risk associated with RT to the supraclavicular region (RR = 1.69, 95% CI: 1.16, 2.46). The most important limitations of the studies were small sample size yielding estimates with low precision, and lack of data on potential confounders.

CONCLUSION

Breast cancer and radiation therapy to the supraclavicular lymph nodes is associated with an increased risk of hypothyroidism.

[What does excess mortality tell us?]

Excess mortality due to covid-19 is estimatedas actual mortality minus expected mortality in the covid-19 period. Excess mortality in 2020-2021 in the Netherlands is estimated to be 30,000 persons. Excess mortality should be divided in mortality as consequences of covid-19 infections (direct effects) and mortality due indirect effects of the pandemic. As excess mortality assesses mortality under one single scenario (the actual scenario including its specific measures), it cannot directly be used to know what the number of deaths would have been under different scenarios. In line, it cannot be used to determine whether actual measures in the covid-19 pandemic were optimal (or not). And obviously, excess mortality only assesses the impact on mortality, not the impact on other relevant health-related, sociological or economical areas.

[What does excess mortality tell us?]

Excess mortality due to covid-19 is estimatedas actual mortality minus expected mortality in the covid-19 period. Excess mortality in 2020-2021 in the Netherlands is estimated to be 30,000 persons. Excess mortality should be divided in mortality as consequences of covid-19 infections (direct effects) and mortality due indirect effects of the pandemic. As excess mortality assesses mortality under one single scenario (the actual scenario including its specific measures), it cannot directly be used to know what the number of deaths would have been under different scenarios. In line, it cannot be used to determine whether actual measures in the covid-19 pandemic were optimal (or not). And obviously, excess mortality only assesses the impact on mortality, not the impact on other relevant health-related, sociological or economical areas.

[Vitamin D supplementation for all older people with COVID-19?]

Vitamin D supplementation has been suggested for many diseases and symptoms that are frequent in older people: loss of bone mineral density, falls, loss of muscle mass, infections (including COVID-19) and mortality. In observational studies, vitamin D concentration has been associated with many poor outcomes, but in most Randomized Controlled Trials, there is no beneficial effect of vitamin D supplementation on these outcomes, except for bone mineral density. An alternative explanation of the observed association may be 'confounding': older people with poor mobility have lower vitamin D, and irrespective of that also have poor outcomes. The recent COVIT-TRIAL seems to suggest there is benefit of high dose vitamin D supplementation compared to low dose on mortality in older people with COVID-19, but on closer methodological look this conclusion does not hold. Clinical guidelines rightly do not advise vitamin D supplementation for a whole range of diseases, including COVID-19.

Clinical and therapeutic diversity in adult chronic nonbacterial osteomyelitis (CNO) of the sternocostoclavicular region: a meta-analysis

OBJECTIVES

Chronic nonbacterial osteomyelitis (CNO) is a rare inflammatory bone disease. The distinct CNO subtype that affects the anterior chest wall is descriptively named sternocostoclavicular hyperostosis (SCCH) and mainly occurs in adults. Literature on CNO/SCCH is scattered and lacks diagnostic and therapeutic consensus.

METHODS

Systematic review and meta-analysis aiming to characterize clinical presentation and therapeutic modalities applied in adult CNO/SCCH patients. Untransformed numerical data and double-arcsine transformed proportional data were pooled in a random effects model in R-4.0.5; proportions were reported with 95% CI.

RESULTS

Forty studies were included, containing data on 2030 and 642 patients for aim 1 and 2, respectively. A female predisposition (67%, 95% CI 60, 73) and major diagnostic delay (5 years 95% CI 3, 7) were noted. Clinical presentation included chest pain (89%, 95% CI 79, 96) and swelling (79%, 95% CI 62, 91). Patients suffered from pustulosis palmoplantaris (53%, 95% CI 37, 68), arthritis (24%, 95% CI 11, 39) and acne (8%, 95% CI 4, 13). Inflammatory markers were inconsistently elevated. Autoantibody and HLA-B27 prevalence was normal, and histopathology unspecific. Increased isotope uptake (99%, 95% CI 96, 100) was a consistent imaging finding. Among manifold treatments, pamidronate and biologicals yielded good response in 83%, 95% CI 60, 98 and 56%, 95% CI 26, 85, respectively.

CONCLUSION

CNO/SCCH literature proves heterogeneous regarding diagnostics and treatment. Timely diagnosis is challenging and mainly follows from increased isotope uptake on nuclear examination. Biopsies, autoantibodies and HLA status are non-contributory, and biochemical inflammation only variably detected. Based on reported data, bisphosphonates and biologicals seem reasonably effective, but due to limitations in design and heterogeneity between studies the precise magnitude of their effect is uncertain. Fundamentally, international consensus seems imperative to advance clinical care for CNO/SCCH.

Is it a risk factor, a predictor, or even both? The multiple faces of multivariable regression analysis

The medical research literature is abundant with regression analyses that include multiple covariates, so-called multivariable regression models. Despite their common application, the interpretation of their results is not always clear or claimed interpretations are not justified. To outline the distinctions between different interpretations, we describe several possible research objectives for which a multivariable regression analysis might be an appropriate way of analyzing the data. In addition, we describe caveats in the interpretation of results of multivariable regression analysis.

Pleomorphic Ventricular Tachycardia in Dilated Cardiomyopathy Predicts Ventricular Tachycardia Recurrence After Ablation Independent From Cardiac Function: Comparison With Patients With Ischemic Heart Disease

BACKGROUND

In dilated cardiomyopathy (DCM), outcome after catheter ablation of ventricular tachycardia (VT) is modest, compared with ischemic heart disease (IHD). Pleomorphic VT (PL-VT) has been associated with fibrotic remodeling and end-stage heart failure in IHD. The prognostic role of PL-VT in DCM is unknown.

METHODS

Consecutive IHD (2009-2016) or DCM (2008-2018) patients undergoing ablation for monomorphic VT were included. PL-VT was defined as ≥1 spontaneous change of the 12-lead VT-morphology during the same induced VT episode. Patients were followed for VT recurrence and mortality.

RESULTS

A total of 247 patients (86% men; 63±13 years; IHD n=152; DCM n=95) underwent ablation for monomorphic VT. PL-VT was observed in 22 and 29 patients with IHD and DCM, respectively (14% versus 31%, P=0.003). In IHD, PL-VT was associated with lower LVEF (28±9% versus 34±12%, P=0.02) and only observed in those with LVEF<40%. In contrast, in DCM, PL-VT was not related to LVEF and induced in 27% of patients with LVEF>40%. During a median follow-up of 30 months, 79 (32%) patients died (IHD 48; DCM 31; P=0.88) and 120 (49%) had VT recurrence (IHD 59; DCM 61; P<0.001). PL-VT was associated with mortality in IHD but not in DCM. In IHD, VT recurrence was independently associated with LVEF, number of induced VTs, and procedural noncomplete success. Of note, in DCM, PL-VT (HR, 2.62 [95% CI, 1.47-4.69]), pathogenic mutation (HR, 2.13 [95% CI, 1.16-3.91]), and anteroseptal VT substrate (HR, 1.75 [95% CI, 1.00-3.07]) independently predicted VT recurrence.

CONCLUSIONS

In IHD, PL-VT was associated with low LVEF and mortality. In DCM, PL-VT was not associated with mortality but a predictor of VT recurrence independent from LVEF. PL-VT in DCM may indicate a specific arrhythmic substrate difficult to control by current ablation techniques.

Volume-Weighted Unipolar Voltage Predicts Heart Failure Mortality in Patients With Dilated Cardiomyopathy and Ventricular Arrhythmias

BACKGROUND

Patients with dilated cardiomyopathy (DCM) who are undergoing catheter ablation of ventricular arrhythmias (VAs) are at risk of rapidly progressive heart failure (HF). Endocardial voltages decrease with loss of viable myocardium. Global left ventricular (LV) voltage as a surrogate for the amount of remaining viable myocardium may predict prognosis.

OBJECTIVES

This study evaluated whether the newly proposed parameter volume-weighted (vw) unipolar voltage (UV) can predict HF-related adverse outcomes (HFOs), including death, heart transplantation, or ventricular assist device implantation, in DCM.

METHODS

In consecutive patients with DCM referred for VA ablation, vwUV was calculated by mathematically integrating UV over the left ventricle, divided by the endocardial LV surface area and wall thickness. Patients were followed for HFOs.

RESULTS

A total of 103 patients (57 ± 14 years of age; LV ejection fraction [LVEF], 39 ± 13%) were included. Median vwUV was 9.75 (IQR: 7.27-12.29). During a median follow-up of 24 months (IQR: 8-47 months), 25 patients (24%) died, and 16 had HFOs 7 months (IQR: 1-18 months) after ablation. Patients with HFOs had significantly lower LVEF (29% ± 10% vs 41% ± 12%), vw bipolar voltage (BV) (3.00 [IQR: 2.47-3.53] vs 5.00 [4.12-5.73]), and vwUV (5.94 [IQR: 5.28-6.55] vs 10.37 [IQR: 8.82-12.81]; all P < 0.001), than patients without HFOs. In Cox regression analysis and goodness-of-fit tests, vwUV was the strongest and independent predictor for HFOs (HR: 3.68; CI: 2.09-6.45; likelihood ratio chi-square, 33.05; P < 0.001).

CONCLUSIONS

The novel parameter vwUV, as a surrogate for the amount of viable myocardium, identifies patients with DCM with VA who are at high risk for HF progression and mortality.

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.

Endocrine-related adverse conditions in patients receiving immune checkpoint inhibition: an ESE clinical practice guideline

Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment but are associated with significant autoimmune endocrinopathies that pose both diagnostic and treatment challenges. The aim of this guideline is to provide clinicians with the best possible evidence-based recommendations for treatment and follow-up of patients with ICI-induced endocrine side-effects based on the Grading of Recommendations Assessment, Development, and Evaluation system. As these drugs have been used for a relatively short time, large systematic investigations are scarce. A systematic approach to diagnosis, treatment, and follow-up is needed, including baseline tests of endocrine function before each treatment cycle. We conclude that there is no clear evidence for the benefit of high-dose glucocorticoids to treat endocrine toxicities with the possible exceptions of severe thyroid eye disease and hypophysitis affecting the visual apparatus. With the exception of thyroiditis, most endocrine dysfunctions appear to be permanent regardless of ICI discontinuation. Thus, the development of endocrinopathies does not dictate a need to stop ICI treatment.

Publication rates in small German trials remained low five years after trial completion

OBJECTIVE

To investigate publication rates in small trials and to explore which factors are associated with publication rates in small trials, including sample size, the type and number of primary and secondary outcomes.

STUDY DESIGN AND SETTING

We studied a subgroup of 'small' trials from a pre-existing dataset (IntoValue), containing German trials completed between 2009 and 2017. Small trials were defined as phase II-III, III and IV trials with 150 or fewer participants. We performed an updated publication search and collected additional data from online trial records.

RESULTS

Out of 499 trials, 325 (65%) trials published their results in a journal article or dissertation. Median time-to-publication was 3.41 years (95% CI: 3.04-4.10). Planned sample size was not associated with publication rates, but the difference between planned and achieved sample size was (per 10% unsuccessfully recruited participants, HR = 0.95, 95% CI: 0.91-1.00). Phase III vs. II-III trials, studied intervention (device vs. other) and clearly vs. unclearly defined primary outcomes predicted a higher likelihood of earlier publication.

CONCLUSION

About 35% of small trials in Germany remain unpublished, even after an extensive follow-up period of over 9 years. Publication rates are low and were associated with sample size, trial phase and type of intervention.