Diagnostic overshadowing: Psychiatric diagnoses, epistemic injustice, and the right to health

Anke Büter

Anke is associate professor at the Department for Philosophy and History of Ideas at Aarhus University, Denmark. She is a philosopher of science and particularly interested in philosophy of medicine and psychiatry. Her recent work focuses on epistemic injustice in relation to psychiatric diagnoses and the value-ladenness of psychiatric research.

People diagnosed with severe mental illnesses die earlier than their mentally healthy counterparts. A meta-analy­sis of 203 English-language cohort studies found a median reduction in life expectancy of about 10 years (excluding substance-abuse disorders).[1] This gap can only partly be ex­plained by elevated suicide rates – mentally ill people mostly die of the same somatic diseases as the rest of the industrialized west, only earlier.[2] It has been estimated that about 60% of the ex­cess mortality in people with severe mental illness is due to physical illness.[3]

Why do the mentally ill lose a decade of their life to somatic illness? The answer to this question is complex. “Life-style factors” related to marginalization and socioeconomic status play a role, as do side-effects of psychotropic drugs. Another important factor is the difficulty in accessing medical help, even in countries with free health care. When interviewed about experiences of discrimination and stigmatization, people with psychiatric diagnoses usually mention physical health care as one of the main problematic areas. In particular, many report not being taken seriously once the doctor knows about their psychiatric diagnosis.[4] [5]

Instead of paying attention to the physical issue at hand, doctors often assume that the problem is psychological in nature. The patients are then discharged or transferred to a psych unit. Examples in the research literature include drastic, sometimes fatal, cases, such as mistaking a stroke, liver failure, or broken legs for a psychological problem, interpreting severe asthma attacks as panic attacks, etc.[6] [7] Obviously, such dramatic misdiagnoses affect health outcomes negatively. In addition, as people with mental illnesses repeatedly experience this kind of disregard and misinterpretation, many report starting to avoid contact with physical health care providers.[8] This further impedes the access to adequate treatment for somatic health issues.

The phenomenon of mistakenly attributing physical symptoms to a psychiatric diagnosis is called “diagnostic overshadowing”. It expresses the common tendency in clinicians to focus on a pre-existing psychiatric diagnosis in a way that leads to misdiagnosis of additional somatic diseases, and thereby to mistreatment or delayed treatment.[9]

Diagnostic overshadowing can be due to prejudices against people with mental illnesses, such as a belief that they tend to be overly dramatic and exaggerate their symptoms. I have argued that many cases of diagnostic overshadowing are cases of a certain kind of epistemic injustice: namely, testimonial injustice.[10] Miranda Fricker has introduced this concept to describe cases where someone is disbelieved because of prejudices against their social group. A classic example would be to assign low credibility to what a woman says on certain technical matters, due to a prejudice about women being incompetent in these regards. Such unfair credibility deflations happen to people with psychiatric diagnoses when seeking medical help for physical symptoms: they are disbelieved because of prejudices about them being either incompetent at self-assessment, or dishonest. Epistemic injustices undermine someone in their capacity as a knower; a capacity that, according to Fricker, is central to our concept of being human. The epistemic injustice involved in diagnostic overshadowing is particularly pernicious, as it targets one’s capacity of self-knowledge in a situation where one is vulnerable and in need of help.

Importantly though, prejudice is not the only source of diagnostic overshadowing. Additional causes are more structural in nature, such as the working conditions of clinicians, their (lack of) training with regard to mental illness, or the lack of integrative healthcare models that can combine mental and physical care. The likelihood of diagnostic overshadowing is exacerbated by a health care system that treats mental illness as an afterthought to physical illness, rather than an integral part of all human health. To overcome this problem, it will therefore be necessary to implement countermeasures on several levels, such as, e.g., taking patient complaints seriously, educating physicians on bias and mental illness, implementing models of integrated care, or improving the general working conditions of health care professionals, such that they have the time to actually listen to patients in the first place.

That something needs to be done seems obvious. Losing access to adequate medical care because of a psychiatric diagnosis is clearly unfair and, ultimately, a violation of human rights. Already in its constitution from 1946, the WHO described the right to health as a fundamental part of human rights. In 1966, the International Covenant on Economic, Social and Cultural Rights (article 12) recognized “the right of everyone to the enjoyment of the highest attainable standard of physical and mental health”. Human rights, moreover, are non-discriminatory: the availability of health care must not be affected by categories such as, e.g., race, sex, gender, religion, political opinion, sexual orientation, disability, or health status.[11]  Discrimination that impedes access to the right diagnosis and treatment is an injustice, and one with devastating consequences.