Potential Consequences of Changing Disease Classifications

Pituitary adenoma or neuroendocrine tumour: the need for an integrated prognostic classification

In the 2022 fifth edition of the WHO Classification of Endocrine Tumours and of Central Nervous System Tumours, pituitary adenomas are reclassified as neuroendocrine tumours (NETs). This change confers an oncology label to neoplasms that are overwhelmingly benign. A comprehensive clinical classification schema is required to guide prognosis, therapy and outcomes for all patients with pituitary adenomas. Pituitary adenomas and NETs exhibit some morphological and ultrastructural similarities. However, unlike NETs, pituitary adenomas are highly prevalent, yet indolent and rarely become malignant. This Perspective presents the outcomes of an interdisciplinary international workshop that addressed the merit and clinical implications of the classification change of pituitary adenoma to NET. Many non-histological factors provide mechanistic insight and influence the prognosis and treatment of pituitary adenoma. We recommend the development of a comprehensive classification that integrates clinical, genetic, biochemical, radiological, pathological and molecular information for all anterior pituitary neoplasms.

Acknowledging and addressing the many ethical aspects of disease

Diseases change the life of individuals, the social status of groups, the obligations of professionals, and the welfare of nations. Disease classifications function as a demarcation of access to care, rights, and duties. Disease also fosters social stigmatization and discrimination, and is a personal, professional, and political matter. It raises a wide range of ethical issues that are of utmost importance in patient communication and education. Accordingly, the objective of this article is to present and discuss a range of basic ethical aspects of this core concept of medicine and health care. First and foremost, disease evokes compassion for the person suffering and induces a moral impetus to health professionals and health policy makers to avoid, eliminate or ameliorate disease. The concept of disease has many moral functions, especially with respect to attributing rights and obligations. Classifying something as disease also has implications for the status and prestige of the condition as well as for the attitudes and behavior towards people with the condition. Acknowledging such effects is crucial for avoiding discrimination and good communication. Moreover, different perspectives on disease can create conflicts between patients, professionals and policy makers. While expanding the concept of disease makes it possible to treat many more people for more conditions - earlier, it also poses ethical challenges of doing more harm than good, e.g., in overdiagnosis, overtreatment, and medicalization. Understanding these ethical issues can be difficult even for health professionals, and communicating them to patients is challenging, but crucial for making informed consent. Accordingly, acknowledging and addressing the many specific ethical aspects of disease is crucial for patient communication and education.

A novel methodological framework was described for detecting and quantifying overdiagnosis

OBJECTIVES

Methods to quantify overdiagnosis of screen detected cancer have been developed, but methods for quantifying overdiagnosis of non-cancer conditions (whether symptomatic or asymptomatic) have been lacking. We aimed to develop a methodological framework for quantifying overdiagnosis that may be used for asymptomatic or symptomatic conditions, and used Gestational Diabetes Mellitus as an example of how it may be applied.

STUDY DESIGN AND SETTING

We identify two earlier definitions for overdiagnosis, a narrower prognosis-based definition, and a wider utility-based definition. Building on the central importance of the concepts of prognostic information and clinical utility of a diagnosis, we consider the following questions: within a target population, do people found to have a disease using one diagnostic strategy but found not to have the disease using another diagnostic strategy (so called 'additional diagnoses'), have an increased risk of adverse clinical outcomes without treatment (prognosis evidence), and/or a decreased risk of adverse outcomes with treatment (utility evidence)?

RESULTS

Using Causal Directed Acyclic Graphs and Fair Umpires, we illuminate the relationships between diagnostics strategies and the frequency of overdiagnosis. We then use the example of Gestational Diabetes Mellitus to demonstrate how the Fair Umpire framework may be applied to estimate overdiagnosis.

CONCLUSION

Our framework may be used to quantify overdiagnosis in non-cancer conditions (and in cancer conditions), as well as to guide further studies on this topic.

Broadening risk factor or disease definition as a driver for overdiagnosis: A narrative review

Medical overuse-defined as the provision of health services for which potential harms exceed potential benefits-constitutes a paradigm of low-value care and is seen as a threat to the quality of care. Value in healthcare implies a precise definition of disease. However, defining a disease may not be straightforward since clinical data do not show discrete boundaries, calling for some clinical judgment. And, if in time a redefinition of disease is needed, it is important to recognize that it can induce overdiagnosis, the identification of medical conditions that would, otherwise, never cause any significant symptoms or lead to clinical harm. A classic example is the impact of recommendations from professional societies in the late 1990s, lowering the threshold for abnormal total cholesterol from 240 mg/dl to 200 mg/dl. Due to these changes in risk factor definition, literally overnight there were 42 million new cases eligible for treatment in the United States. The same happened with hypertension-using either the 2019 NICE guidelines or the 2018 ESC/ECC guidelines criteria for arterial hypertension, the proportion of people overdiagnosed with hypertension was calculated to be between 14% and 33%. In this review, we will start by discussing resource overuse. We then present the basis for disease definition and its conceptual problems. Finally, we will discuss the impact of changing risk factor/disease definitions in the prevalence of disease and its consequences in overdiagnosis and overtreatment (a problem particularly relevant when definitions are widened to include earlier or milder disease).

The impact of health literacy on psychosocial and behavioural outcomes among people at low risk of cardiovascular disease

This study aimed to explore the impact of health literacy on psychosocial and behavioural outcomes for people who were not at high risk of cardiovascular disease receiving a hypothetical blood pressure reading of 135/85 mmHg. We performed a secondary analysis of data from a national sample of Australians aged 40 to 50 years (n = 1318) recruited online. Health literacy was measured using the validated Newest Vital Sign (inadequate: 0-3; adequate: 4-6). Analysed outcomes included: willingness to increase exercise and accept medication; perceived severity; positive and negative affect; illness perceptions and impacts on life and motivation. Participants with inadequate levels of health literacy perceived a blood pressure reading of 135/85 mmHg to be less serious compared to individuals with adequate health literacy (Mean Difference [MD]:0.21; 95%CI 0.03-0.39; p = .024; d = 0.13), and reported less motivation to eat well (MD:0.44; 95%CI 0.31-0.58; p < .001; d = 0.38) and exercise (MD:0.43; 95%CI 0.31-0.58; p < .001; d = 0.36). However, they were more willing to accept medication (MD:0.20; 95%CI 0.07-0.34; p = .004; d = 0.17). Participants with inadequate health literacy also perceived the condition to have fewer negative impacts on aspects of life and work than individuals with adequate health literacy, but reported greater negative emotion and more negative illness perceptions (all p < .001). Tailored communication and behaviour change support may be needed when communicating blood pressure information to people with lower health literacy and not at high risk of cardiovascular disease given the differential impacts on medication (increased willingness) and healthy exercise and diet behaviours (decreased willingness) observed in this study.

Early-stage symptomatic osteoarthritis of the knee - time for action

Osteoarthritis (OA) remains the most challenging arthritic disorder, with a high burden of disease and no available disease-modifying treatments. Symptomatic early-stage OA of the knee (the focus of this Review) urgently needs to be identified and defined, as efficient early-stage case finding and diagnosis in primary care would enable health-care providers to proactively and substantially reduce the burden of disease through proper management including structured education, exercise and weight management (when needed) and addressing lifestyle-related risk factors for disease progression. Efforts to define patient populations with symptomatic early-stage knee OA on the basis of validated classification criteria are ongoing. Such criteria, as well as the identification of molecular and imaging biomarkers of disease risk and/or progression, would enable well-designed clinical studies, facilitate interventional trials, and aid the discovery and validation of cellular and molecular targets for novel therapies. Treatment strategies, relevant outcomes and ethical issues also need to be considered in the context of the cost-effective management of symptomatic early-stage knee OA. To move forwards, a multidisciplinary and sustained international effort involving all major stakeholders is required.

Benefits and Harms of Hypertension and High-Normal Labels: A Randomized Experiment

BACKGROUND

Recent US guidelines lowered the threshold for diagnosing hypertension while other international guidelines use alternative/no labels for the same group (blood pressure [BP], <140/90 mm Hg). We investigated potential benefits and harms of hypertension and high-normal BP labels, compared with control, among people at lower risk of cardiovascular disease.

METHODS

We conducted a randomized experiment using a national sample of Australians (n=1318) 40 to 50 years of age recruited from an online panel. Participants were randomized to 1 of 3 hypothetical scenarios where a general practitioner told them they had a BP reading of 135/85 mm Hg, using either hypertension/high-normal BP/control (general BP description) labels. Participants were then randomized to receive an additional absolute risk description or nothing. Primary outcomes were willingness to change diet and worry. Secondary outcomes included exercise/medication intentions, risk perceptions, and other psychosocial outcomes.

RESULTS

There was no difference in willingness to change diet across label groups (P=0.22). The hypertension label (mean difference [MD], 0.74 [95% CI, 0.41-1.06]; P<0.001) and high-normal BP label (MD, 0.45 [95% CI, 0.12-0.78]; P=0.008) had increased worry about cardiovascular disease risk compared with control. There was no evidence that either label increased willingness to exercise (P=0.80). However, the hypertension (MD, 0.20 [95% CI, 0.04-0.36]; P=0.014), but not high-normal label (MD, 0.06 [95% CI, -0.10 to 0.21]; P=0.49), increased willingness to accept BP-lowering medication compared with control. Psychosocial differences including lower control, higher risk perceptions, and more negative affect were found for the hypertension and high-normal labels compared with control. Providing absolute risk information decreased willingness to change diet (MD, 0.25 [95% CI, 0.10-0.41]; P=0.001) and increase exercise (MD, 0.28 [95% CI, 0.11-0.45]; P=0.001) in the hypertension group.

CONCLUSIONS

Neither hypertension nor high-normal labels motivated participants to change their diet or exercise more than control, but both labels had adverse psychosocial outcomes. Labeling people with systolic BP of 130 to 140 mm Hg, who are otherwise at low risk of cardiovascular disease, may cause harms that outweigh benefit. Registration: URL: http://www.anzctr.org.au/; Unique identifier: ACTRN12618001700224.

Pituitary Neoplasm Nomenclature Workshop: Does Adenoma Stand the Test of Time?

The WHO Classification of Endocrine Tumours designates pituitary neoplasms as adenomas. A proposed nomenclature change to pituitary neuroendocrine tumors (PitNETs) has been met with concern by some stakeholder groups. The Pituitary Society coordinated the Pituitary Neoplasm Nomenclature (PANOMEN) workshop to address the topic. Experts in pituitary developmental biology, pathology, neurosurgery, endocrinology, and oncology, including representatives nominated by the Endocrine Society, European Society of Endocrinology, European Neuroendocrine Association, Growth Hormone Research Society, and International Society of Pituitary Surgeons. Clinical epidemiology, disease phenotype, management, and prognosis of pituitary adenomas differ from that of most NETs. The vast majority of pituitary adenomas are benign and do not adversely impact life expectancy. A nomenclature change to PitNET does not address the main challenge of prognostic prediction, assigns an uncertain malignancy designation to benign pituitary adenomas, and may adversely affect patients. Due to pandemic restrictions, the workshop was conducted virtually, with audiovisual lectures and written précis on each topic provided to all participants. Feedback was collated and summarized by Content Chairs and discussed during a virtual writing meeting moderated by Session Chairs, which yielded an evidence-based draft document sent to all participants for review and approval. There is not yet a case for adopting the PitNET nomenclature. The PANOMEN Workshop recommends that the term adenoma be retained and that the topic be revisited as new evidence on pituitary neoplasm biology emerges.

The potential for overdiagnosis and underdiagnosis because of blood pressure variability: a comparison of the 2017 ACC/AHA, 2018 ESC/ESH and 2019 NICE hypertension guidelines

OBJECTIVE

To estimate the extent that BP measurement variability may drive over- and underdiagnosis of 'hypertension' when measurements are made according to current guidelines.

METHODS

Using data from the National Health and Nutrition Examination Survey and empirical estimates of within-person variability, we simulated annual SBP measurement sets for 1 000 000 patients over 5 years. For each measurement set, we used an average of multiple readings, as recommended by guidelines.

RESULTS

The mean true SBP for the simulated population was 118.8 mmHg with a standard deviation of 17.5 mmHg. The proportion overdiagnosed with 'hypertension' after five sets of office or nonoffice measurements using the 2017 American College of Cardiology guideline was 3-5% for people with a true SBP less than 120 mmHg, and 65-72% for people with a true SBP 120-130 mmHg. These proportions were less than 1% and 14-33% using the 2018 European Society of Hypertension and 2019 National Institute for Health and Care Excellence guidelines (true SBP <120 and 120-130 mmHg, respectively). The proportion underdiagnosed with 'hypertension' was less than 3% for people with true SBP at least 140 mmHg after one set of office or nonoffice measurements using the 2017 American College of Cardiology guideline, and less than 18% using the other two guidelines.

CONCLUSION

More people are at risk of overdiagnosis under the 2017 American College of Cardiology guideline than the other two guidelines, even if nonoffice measurements are used. Making clinical decisions about cardiovascular prediction based primarily on absolute risk, minimizes the impact of blood pressure variability on overdiagnosis.

Development of a Severity Classification System for Sickle Cell Disease

Purpose

There is no well-accepted classification system of overall sickle cell disease (SCD) severity. We sought to develop a system that could be tested as a clinical outcome predictor.

Patients and Methods

Using validated methodology (RAND/UCLA modified Delphi panel), 10 multi-disciplinary expert clinicians collaboratively developed 180 simplified patient histories and rated each on multiple axes (estimated clinician follow-up frequency, risk of complications or death, quality of life, overall disease severity). Using ratings on overall disease severity, we developed a 3-level severity classification system ranging from Class I (least severe) to Class III (most severe).

Results

The system defines patients as Class I who are 8-40 years with no end organ damage, no chronic pain, and ≤4 unscheduled acute care visits due to vaso-occlusive crises (VOC) in the last year. Patients <8 or >40 years with no end organ damage, no chronic pain, and <2 unscheduled acute care visits are also considered Class I. Patients any age with ≥5 unscheduled acute care visits and/or with severe damage to bone, retina, heart, lung, kidney, or brain are classified as Class III (except patients ≥25 years with severe retinopathy, no chronic pain, and 0-1 unscheduled acute care visits, who are considered Class II). Patients not meeting these Class I or III definitions are classified as Class II.

Conclusion

This system consolidates patient characteristics into homogenous groups with respect to disease state to support clinical decision-making. The system is consistent with existing literature that increased unscheduled acute care visits and organ damage translate into clinically significant patient morbidity. Studies to further validate this system are planned.