Afraid that's not true. Around 60-80% of diagnoses in primary care settings are made purely on the basis of the patient history (followed by a brief clinical examination which usually aims at eliciting subjective responses)[1]. In principle it's true that you could find a pathological explanation for all somatic ("physical") diseases which in practice are diagnosed off patient histories (with the exception of diseases for which the pathogenesis is unknown, f.ex. fibromyalgia, IBS, CFS, etc). However - in principle - the same goes for mental illnesses, although the pathogenesis of mental illnesses are generally poorly understood. If you don't think there's a physical basis for mental illnesses though, skim through the figures in this article[2] for a prime example of the ways modern medicine is disproving that. Diagnoses of both mental and somatic illnesses are heavily based off subjective factors, and both mental and somatic illnesses have very real pathophysiological etiologies.
There are objective tests for all of these pathologies, though those tests are often inconclusive in the face of the symptoms.
>If you don't think there's a physical basis for mental illnesses though, skim through the figures in this article[2] for a prime example of the ways modern medicine is disproving that.
There are physical symptoms of mental illness, but as yet there is no proof of physical causes, which is why the chairman of the Department of Psychiatry at Duke University School of Medicine and the DSM-4 stated "psychiatric diagnosis still relies exclusively on fallible subjective judgments rather than objective biological tests". You'll find no objective biological tests in the DSM.
>There are objective tests for all of these pathologies, though those tests are often inconclusive in the face of the symptoms.
Nothing good, sadly.
My wife was in banking for twelve years and worked her way up from a teller to a fairly senior position. Her work ethic was spectacular - she had just two sick days in the previous five years and she was promoted almost yearly, always receiving an excellent review.
A few years ago, she went from having occasional discomfort to waking with fairly severe pain daily. It got so bad that she had to take time off, and eventually took FMLA for a full twelve weeks to see if it would help. It didn't and she was fired soon after.
She filed for disability after being diagnosed with Fybromyalgia. Our lawyer sent her to bother specialist doctors and independent testing labs to get complete documentation. They had her complete various tasks like screwing in a screwdriver, raising a weight above her head for X seconds etc. and then asked her to rate her pain levels and other self-reported things.
In the end, she was denied for disability, mostly because disability is no longer about actually being disabled - it's now about essentially filling the gap between welfare and medicaid. In the written opinion however, the stated reason was that all the evidence was self-reported, implying she could be making it all up (because who wouldn't want to give up a successful and lucrative career for some minimal-level disability payments).
Anyway, I learned two main things:
1. There are no commonly accepted objective tests for pain - it's almost all self-reporting.
2. The disability system in the US is heavily used as supplemental welfare.
> There are objective tests for all of these pathologies, though those tests are often inconclusive in the face of the symptoms.
No, objective tests are in these cases used to exclude other causes to the symptoms, not to diagnose the mentioned illnesses. These are diagnoses of exclusion[1].
> There are physical symptoms of mental illness, but as yet there is no proof of physical causes, which is why the chairman of the Department of Psychiatry at Duke University School of Medicine and the DSM-4 stated "psychiatric diagnosis still relies exclusively on fallible subjective judgments rather than objective biological tests". You'll find no objective biological tests in the DSM.
I'm not disputing the fact that it's not possible to do pathophysiological tests for mental illnesses in current clinical practice, but you're creating a false equivalence by implying that being unable to test for a pathophysiological factor is the same as that factor not existing. There are plenty of pathophysiological changes that occur in mental illnesses [2-4], but for obvious reasons it's not feasible to haphazardly take biopsies of the brain to test for them, especially when the patient history and subjective examinations suffice to make a diagnosis in most cases.
Conversely, my point still stands that the vast majority of somatic illnesses are diagnosed off subjective symptoms - doctors don't bother doing objective lab tests for a cold or a sprained ankle when the diagnosis is glaringly obvious based off subjective symptoms.
>it's not feasible to haphazardly take biopsies of the brain to test for them
It is feasible post mortem but scientists still have no conslusive proof from such examinations.
>Conversely, my point still stands that the vast majority of somatic illnesses are diagnosed off subjective symptoms - doctors don't bother doing objective lab tests for a cold or a sprained ankle when the diagnosis is glaringly obvious based off subjective symptoms.
That is not in dispute because a cold and sprained ankle are objectively diagnosable post mortem. Mental illness is not.
You're creating the same false equivalence again by stating that an objective post mortem diagnosis not being practically feasible is the same as an objective cause(s) not existing. In my previous post I linked to multiple pages listing objective causes/mechanisms for two mental illnesses. Diagnosing a mental illness post mortem isn't as simple as finding rhinovirus in a person's nasal cavity, but just because the current knowledge of the disease isn't sufficient to create a satisfactory model that can reliably make a diagnosis post mortem doesn't mean that it can't be done. And if you don't think mental illnesses subside in molecules and physical structures in the brain, where exactly do you think they come from?
>if you don't think mental illnesses subside in molecules and physical structures in the brain, where exactly do you think they come from?
No ones knows for sure because no one can objectively explain the nature of consciousness and the mind in the first place. That is of course not to say that chemicals do not have a strong influence on the mind.
The study has no control group and therefore is not objective. If you read the Methodological Issues section, you'll see that this is essentially a study of the neurochemical effects of antipsychotic drugs.
> No ones knows for sure because no one can objectively explain the nature of consciousness and the mind in the first place.
True, but I'm still waiting for a single proposal as to where a mental illness would subside other than physical structures/molecules, because the only other explanation I can think of are in the realm of the metaphysical
> The study has no control group and therefore is not objective. If you read the Methodological Issues section, you'll see that this is essentially a study of the neurochemical effects of antipsychotic drugs.
The article isn't a study/original research, it's a review based off of existing research - generally - in which brains from individuals with schizophrenia are compared to the brains of individuals without schizophrenia (controls). Antipsychotic drugs as a confounding factor is definitely an important factor in these studies though. There are however a number of factors that are are not affected by antipsychotics, notably genetics[1, 2]. Certain genetic variants strongly increase the risk of mental illnesses - by what mechanism does this work other than by translating to proteins that exert an objective, physical effect? (Note that studies on this are primarily GWAS based on large populations, not simple hereditary/familial studies in which one could argue that environmental factors were confounding)
This is partly because when a specific physiological cause for a "mental illness" is confirmed, it usually becomes its own diagnosis in a different specialty. This happened relatively recently with anti-NMDA receptor encephalitis, which is believed to be responsible for some cases diagnosed as schizophrenia (and, historically, as demonic possession).
[1] Source: medical school. Not finding a study with exact numbers from a quick search. [2] https://www.nature.com/nm/journal/v23/n1/full/nm.4246.html