Infectious diseases figure prominently as (counter)examples in debates on how to conceptualize “disease.” But crucial epidemiological distinctions are often not heeded in the debate, and pathological and clinical perspectives focusing on individual patients are favored at the expense of perspectives from epidemiology focusing on populations. In clarifying epidemiological concepts, this paper highlights the distinct contributions infectious disease epidemiology can make to the conception of “disease,” and the fact that this is at least tacitly recognized by medical personnel and philosophers. Crucially, (...) infectious disease epidemiology can help elucidate how carrying and transmitting infectious, communicable entities is a disease, even if the carriers themselves are not directly affected by symptoms detrimental to them. (shrink)

Nudges are means to influence the will formation of people to make specific choices more likely. My focus is on nudges that are supposed to improve the health condition of individuals and populations over and above the direct prevention of disease. I point out epistemic and moral problems with these types of nudges, which lead to my conclusion that health-enhancing nudges fail. They fail because we cannot know which choices enhance individual health—properly understood in a holistic way—and because health-enhancing nudges (...) are often themselves bad for our health. They can be bad for our health because they assume inferior agency in their targets and accordingly regularly lead to appropriate resentment and anger—strong emotions which go along with an increased risk of health impairments. Briefly, health-enhancing nudges fail because they are based on persistent ignorance and on a presumptuous attitude. (shrink)

Recently, concerns have been raised about the phenomenon of ‘overdiagnosis’, the diagnosis of a condition that is not causing harm, and will not come to cause harm. Along with practical, ethical, and scientific questions, overdiagnosis raises questions about our concept of disease. In this paper, we analyse overdiagnosis as an epistemic problem and show how it challenges many existing accounts of disease. In particular, it raises ques- tions about conceptual links drawn between disease and dysfunction, harm, and risk. We argue (...) that ‘disease’ should be considered a vague concept with a non-classical structure. On this view, overdiagnosed cases are ‘borderline’ cases of disease, falling in the zone between cases that are clearly disease, and cases that are clearly not disease. We then develop a pre ́cising definition of disease designed to provide practical help in preventing and limiting overdiagnosis. We argue that for this purpose, we can define disease as dysfunction that has a significant risk of causing severe harm to the patient. (shrink)

In this paper, we examine recent critiques of the debate about defining disease, which claim that its use of conceptual analysis embeds the problematic assumption that the concept is classically structured. These critiques suggest, instead, developing plural stipulative definitions. Although we substantially agree with these critiques, we resist their implication that no general definition of “disease” is possible. We offer an alternative, inductive argument that disease cannot be classically defined and that the best explanation for this is that the concept (...) is structured as a cluster. We further argue that we do not need to reject the possibility of defining the general concept “disease” to legitimate developing stipulative definitions of disease that are relative to particular purposes. A cluster definition of disease is compatible with contextually motivated definitions, which may be considered précisifications of the more general cluster concept. (shrink)

I argue that ductal carcinoma in situ (DCIS), the tumor most commonly diagnosed by breast mammography, cannot be confidently classified as cancer, that is, as pathological. This is because there may not be dysfunction present in DCIS—as I argue based on its high prevalence and the small amount of risk it conveys—and thus DCIS may not count as a disease by dysfunction-requiring approaches, such as Boorse’s biostatistical theory and Wakefield’s harmful dysfunction account. Patients should decide about treatment for DCIS based (...) on the risks it poses and the risks and benefits of treatment, not on its disease status. (shrink)

In a series of recent papers, I have made three arguments about how to define “disease” and evaluate and apply possible definitions. First, I have argued that definitions should not be seen as traditional conceptual analyses, but instead as proposals about how to define and use the term “disease” in the future. Second, I have pointed out and attempted to address a challenge for dysfunction-requiring accounts of disease that I call the “line-drawing” problem: distinguishing between low-normal functioning and dysfunctioning. Finally, (...) I have used a dysfunction-requiring approach to argue that some extremely prevalent conditions, such as high blood pressure, high cholesterol, and ductal carcinoma in situ, are not diseases, but instead are risk factors. Four of the papers in this issue directly engage my previous work. In this commentary, I applaud the advances these authors make, address points of disagreement, and make suggestions about where the discussion should go next. (shrink)

Alzheimer’s Disease (AD) provides an excellent case study to investigate emerging conceptions of health, disease, pre-disease, and risk. Two scientific working groups have recently reconceptualized AD and created a new category of asymptomatic biomarker positive persons, who are either said to have preclinical AD, or to be at risk for AD. This article examines how prominent theories of health and disease would classify this condition: healthy or diseased? Next, the notion of being “at risk”—a state somewhere in-between health and disease—is (...) considered from various angles. It is concluded that medical-scientific developments urge us to let go of dichotomous ways of understanding disease, that the notion of “risk,” conceptualized as an increased chance of getting a symptomatic disease, might be a useful addition to our conceptual framework, and that we should pay more attention to the practical usefulness and implications of the ways in which we draw lines and define concepts. (shrink)

This paper seeks to develop a theory of health that aligns with the shift in contemporary medical practice and research toward a temporally extended epidemiological view of health. The paper describes how such a theory is at the core of life course based approaches to health, and finds theoretical grounding in recent work in the philosophy of biology promulgating a process theory of life.

With the growing focus on prevention in medicine, studies of how to describe risk have become increasing important. Recently, some researchers have argued against giving patients “comparative risk information,” such as data about whether their baseline risk of developing a particular disease is above or below average. The concern is that giving patients this information will interfere with their consideration of more relevant data, such as the specific chance of getting the disease (the “personal risk”), the risk reduction the treatment (...) provides, and any possible side effects. I explore this view and the theories of rationality that ground it, and I argue instead that comparative risk information can play a positive role in decision-making. The criticism of disclosing this sort of information to patients, I conclude, rests on a mistakenly narrow account of the goals of prevention and the nature of rational choice in medicine. (shrink)

BackgroundEnhancement involves the use of biomedical technologies to improve human capacities beyond therapeutic purposes. It has been well documented that enhancement is sometimes difficult to distinguish from treatment. As a subtype of enhancement, neuroenhancement aims to improve one’s cognitive or emotional capacities.Main bodyThis article proposes that the notion of neuroenhancement deserves special attention among enhancements in general, because apart from the notion of treatment, it also overlaps with other concepts such as prevention, pain relief, and pleasure seeking. Regarding prevention, patients’ (...) mental endurance can be enhanced when a patient is prescribed a selective serotonin reuptake inhibitor for the purpose of preventing the relapse of depression following a stressful situation. As for pain relief, psychiatrists use medication to alleviate distress in patients who experience various types of anxiety; the alleviation of distress is equal to psychological pain relief, but is also an enhancement of the patient’s temperamental traits. Regarding pleasure seeking, insidious transition exists between neuroenhancement and pleasure seeking when using psychotropic drugs. It is well known that people use psychostimulants for recreational purposes and to induce overconfidence in one’s performance. The polysemy of psychotropics derives from their effects on human sensibility. Therefore, when using psychotropic agents, psychiatrists should pay close attention to what the agent is used for on each patient in each situation, and explicitly share the continuity and overlap in the purpose of prescribing a medication with the patients to make a better clinical decision.ConclusionsThe notion of neuroenhancement overlaps not only with the notion of treatment, but also with other concepts of prevention, pain relief, and pleasure seeking. The continuity between those concepts makes the issues concerning the prescription of psychotropic drugs subtler. Psychiatrists should explicitly share the continuity with the patients to make a better clinical decision. (shrink)

Biological dysfunction is regarded, in many accounts, as necessary and perhaps sufficient for disease. But although disease is conceptualized as all-or-nothing, biological functions often differ by degree. A tension is created by attempting to use a continuous variable as the basis for a categorical definition, raising questions about how we are to pinpoint the boundary between health and disease. This is the line-drawing problem. In this paper, we show how the line-drawing problem arises within “dysfunction-requiring” accounts of disease, such as (...) those of Christopher Boorse and Jerome Wakefield. We then provide several detailed examples to establish that biological dysfunction cannot provide a boundary. We examine potential ways of resolving the line-drawing problem, either by dropping one of the claims that generates it, or by appealing to additional criteria. We argue that two of these options are plausible, and that each of these can be applied with regard to different diseases. (shrink)

Are the small and indolent cancers found in abundance in cancer screening normal variations, risk factors, or disease? Naturalists in philosophy of medicine turn to pathophysiological findings to decide such questions objectively. To understand the role of pathophysiological findings in disease definition, we must understand how they mislead in diagnostic reasoning. Participants on all sides of the definition of disease debate attempt to secure objectivity via reductionism. These reductivist routes to objectivity are inconsistent with the Bayesian nature of clinical reasoning; (...) when they appeal to the sciences, they are inconsistent with what philosophy of biology tells us about its natural kinds. Proposals that we narrow the scope of our claims in the disease definition debates are useful, but paradigms can still distort our reasoning in particular cases, even when we are self-conscious about their status. (shrink)

What clinicians, biomedical scientists, and other health care professionals know as individuals or as groups and how they come to know and use knowledge are central concerns of medical epistemology. Activities associated with knowledge production and use are called epistemic practices. Such practices are considered in biomedical and clinical literatures, social sciences of medicine, philosophy of science and philosophy of medicine, and also in other nonmedical literatures. A host of different kinds of knowledge claims have been identified, each with different (...) uses and logics of justification. A general framework is needed to situate these diverse contributions in medical epistemology, so we can see how they fit together. But developing such a framework turns out to be quite tricky. In this survey, three possible frameworks are considered along with the difficulties associated with each of them. The essay concludes with a fourth framework, which considers any epistemology as part of a practice that is oriented toward overcoming errors that emerge in antecedently given practices where knowledge is developed and used. As medicine indirectly advances health by directly mitigating disease, so epistemology indirectly advances knowledge by directly mitigating error. (shrink)

Overdiagnosis and disease are related concepts. Widened conceptions of disease increase overdiagnosis and vice versa. This is partly because there is a close and complex relationship between disease and overdiagnosis. In order to address the problems with overdiagnosis, we may benefit from a closer understanding this relationship. Accordingly, the objective of this article is to elucidate the relationship between disease and overdiagnosis. To do so, the article starts with scrutinizing how overdiagnosis can explain the expansion of the concept of disease. (...) Then it investigates how definitions of disease address various challenges of overdiagnosis. The article specifically investigates recent attempts to clarify the relationship between the concepts of disease and overdiagnosis. Several shortcomings are identified and lead to a closer analysis of overdiagnosis in the diagnostic process. Contrary to recent contributions to the field, it is argued that cases of overdiagnosis are not cases of disease. They are non-verified labelling of disease. It is revealed how overdiagnosis establishes an unwarranted link between indicative phenomena, such as polyps or cell changes, and harm, and thereby generates a link to disease. One implication of this study is that we should stop attributing disease language to indicative phenomena. That is, we should stop calling it “cancer screening” when we are actually searching for polyps. Another implications is that we should strive for scientific progress in differentiating phenomena that are of negative value to us from those that are not. In overdiagnosis we diagnose something that is not disease: it is over-diagnosis. (shrink)

Medicalization is frequently defined as a process by which some non-medical aspects of human life become to be considered as medical problems. Overdiagnosis, on the other hand, is most often defined as diagnosing a biomedical condition that in the absence of testing would not cause symptoms or death in the person’s lifetime. Medicalization and overdiagnosis are related concepts as both expand the extension of the concept of disease. They are both often used normatively to critique unwarranted or contested expansion of (...) medicine and to address health services that are considered to be unnecessary, futile, or even harmful. However, there are important differences between the concepts, as not all cases of overdiagnosis are medicalizations and not all cases of medicalizations are overdiagnosis. The objective of this article is to clarify the differences between medicalization and overdiagnosis. It will demonstrate how the subject matter of medicalization traditionally has been non-medical (social or cultural everyday life) phenomena, while the subject matter of overdiagnosis has been biological or biomolecular conditions or processes acknowledged being potentially harmful. They also refer to different types of uncertainty: medicalization is concerned with indeterminacy, while overdiagnosis is concerned with lack of prognostic knowledge. Medicalization is dealing with sickness (sick role) while overdiagnosis with disease. Despite these differences, medicalization and overdiagnosis are becoming more alike. Medicalization is expanding, encompassing the more “technical” aspects of overdiagnosis, while overdiagnosis is becoming more ideologized. Moreover, with new trends in modern medicine, such as P4 (preventive, predictive, personal, and participatory) medicine, medicalization will become all-encompassing, while overdiagnosis more or less may dissolve. In the end they may converge in some total “iatrogenization.” In doing so, the concepts may lose their precision and critical sting. (shrink)

How can we draw the line between health and disease? This crucial question of demarcation has immense practical implications and has troubled scholars for ages. The question will be addressed in three steps. First, I will present an important contribution by Rogers and Walker who argue forcefully that no line can be drawn between health and disease. However, a closer analysis of their argument reveals that a line-drawing problem for disease-related features does not necessarily imply a line-drawing problem for disease (...) as such. The second step analyzes some alternative approaches to drawing the line between health and disease. While these approaches do not provide full answers to the question, they indicate that the line-drawing question should not be dismissed too hastily. The third step investigates whether the line-drawing problem can find its solution in the concept of suffering. In particular, I investigate whether returning to the origin of medicine, with the primary and ultimate goal of reducing suffering, may provide sources of demarcation between health and disease. In fact, the reason why we pay attention to particular phenomena as characteristics of disease, consider certain processes to be relevant, and specific functions are classified as dys-functions, is that they are related to suffering. Accordingly, using suffering as a criterion of demarcation between health and disease may hinder a wide range of challenges with modern medicine, such as unwarranted expansion of disease, overdiagnosis, overtreatment, and medicalization. (shrink)

Christopher Boorse’s bio-statistical theory of health and disease argues that the central discipline on which theoretical medicine relies is physiology. His theory has been much discussed but little has been said about its focus on physiology or, conversely, about the role that other biomedical disciplines may play in establishing a theoretical concept of health. Since at least the 1950s, epidemiology has gained in strength and legitimacy as an independent medical science that contributes to our knowledge of health and disease. Indeed, (...) it not only provides important information about disease distribution and aetiology, but the risk-factor approach it employs seems to challenge BST’s binary conception of health and disease. The objective of the article is to show, firstly, how important information deriving from descriptive and analytical epidemiology forms part of our contemporary medical concepts of health and disease, and secondly, that these elements are not taken into account by BST in a satisfactory way. The article’s central contention, therefore, is that if the project of defining the theoretical concept of health is to be maintained, more importance should be accorded to the contribution made by epidemiology—alongside physiology—in defining health. (shrink)

What kind of a thing are chronic diseases? Are they objects, bundles of signs and symptoms, properties, processes, or fictions? Rather than using concept analysis—the standard approach to disease in the philosophy of medicine—to answer this metaphysical question, I use a bottom-up, inductive approach. I argue that chronic diseases are bodily states or properties—often dispositional, but sometimes categorical. I also investigate the nature of related pathological entities: pathogenesis, etiology, and signs and symptoms. Finally, I defend my view against alternate accounts (...) of the nature of disease. (shrink)

This essay replies to critics since 1995 of my “biostatistical theory” of health. According to the BST, a pathological condition is a state of statistically species-subnormal biological part-functional ability, relative to sex and age. Theoretical health, the total absence of pathological conditions, is then a value-free scientific notion. Recent critics offer a mixture of old and new objections to this analysis. Some new ones relate to choice of reference class, situation-specificity of function, common diseases and healthy populations, improvements in population (...) health, the practice of pathologists, “Cambridge changes” in health status, and comparative vs. absolute health concepts. I make no changes in doctrine, except to consider treating “normal aging” as pathological by taking young adults as the standard for all adults. (shrink)

Elselijn Kingma argues that Christopher Boorse’s biostatistical theory does not show how the reference classes it uses—namely, age groups of a sex of a species—are objective and naturalistic. Boorse has replied that this objection is of no concern, because there are no examples of clinicians’ choosing to use reference classes other than the ones he suggests. Boorse argues that clinicians use the reference classes they do because these reflect the natural classes of organisms to which their patients belong. Drawing on (...) a thorough exploration of how the disease osteoporosis is defined in adults, I argue that clinicians do indeed make choices about which reference classes to use in diagnosis. Clinicians use young adult reference classes to diagnose osteoporosis in elderly patients. They also use young female reference classes to diagnose osteoporosis in elderly males. Clinicians adjust their reference classes so that the diagnosis of osteoporosis reflects a person’s risk of sustaining a fragility fracture. The ethical intuition that people with the same risk of fracture should receive the same diagnosis overwhelms the naturalistic intuition that reference classes should reflect natural classes of organisms of uniform functional design. Clinicians construct a variety of reference class types, including pathological reference classes and epidemiological population-specific reference classes, to serve this ethical intuition. I show how clinicians use several reference classes at once so that they can more accurately predict risk of fracture. Ultimately, the reference classes chosen and used in medical practice are quite different from those proposed in naturalistic philosophy of medicine. (shrink)

The article examines the relationship between a trait’s effect on survival and reproduction and the notion of functional efficiency underlying the biostatistical theory of health. BST faces the problem of how to measure a trait’s joint effect on survival and reproduction in its account of function. If one measures the joint effect by means of the biological notion of fitness, examples such as the hereditary breast and ovarian cancer syndrome do not count as a disorder. If one does not invoke (...) biological fitness, it is unclear how to measure the joint effect while keeping to BST’s naturalist credentials. (shrink)

Philosophers of medicine have formulated different accounts of the concept of disease. Which concept of disease one assumes has implications for what conditions count as diseases and, by extension, who may be regarded as having a disease and for who may be accorded the social privileges and personal responsibilities associated with being sick. In this article, we consider an ideal diagnostic test for coronavirus disease 2019 infection with respect to four groups of people—positive and asymptomatic; positive and symptomatic; negative; and (...) untested—and show how different concepts of disease impact on the disease and sickness judgements for these groups. The suggestion is that sickness judgements and social measures akin to those experienced during the current COVID-19 outbreak presuppose a concept of disease containing social harm as a component. We indicate the problems that arise when adopting this kind of disease concept beyond a state of emergency. (shrink)

This thesis is about the notions of health and pathology in medical theory. I develop a theory, which defines ‘health’ and ‘pathology’ in a way that solves several problems with earlier suggestions of how to define these terms. I call the theory ‘the disposition profile efficiency theory’, abbreviated ‘the DPE-theory’. According to the DPE-theory, a trait token is healthy, roughly, if and only if all of its dispositions for performing physiological functions are efficient enough. A trait token is pathological, roughly, (...) if and only if at least one of its dispositions for performing a physiological function is not efficient enough. The notion of efficiency, I suggest, is reference class-relative: the efficiency of a trait token’s disposition for performing a physiological function expresses a relation between the trait token and a health standard for the trait token’s bearer’s reference class. The thesis also examines the most discussed theory of health and pathology, “the biostatistical theory” proposed by Boorse. Both the DPE-theory and the biostatistical theory are evaluated against a number of desiderata: the theory should be theoretically sound; only use empirical, statistical, and logical terms; not involve values; be clear; both account for health and pathology as reference class-relative properties, and account for the importance of integration of different physiological functions for health; and have reasonable implications. It is argued that the DPE-theory satisfies the desiderata, and that it does so better than the biostatistical theory. The main contributions of the thesis are the DPE-theory’s models of dispositions, its approach to defining reference classes, its efficiency measure, and its way of drawing the line between high enough efficiencies and too low efficiencies. Other important contributions concern the desideratum about reasonable implications. It is shown how the DPE-theory contributes to solving two much discussed objections directed towards the biostatistical theory, “the problem of common diseases” and “Kingma’s dilemma”. Further, the DPE-theory is used to illuminate discussions about certain types of conditions for which it is contested whether they should count as healthy or pathological. (shrink)