Is mental illness the same as physical illness?

Lots of people ask this question, or variants on it. Perhaps not that it’s real, but is it what it says it is? There are many possible answers, and these may depend on what is meant by mental illness; but, to my mind, if something has gone wrong with your brain, then you are probably mentally ill. If something was wrong with your liver that caused you unpleasant symptoms, then no one would argue whether you were ill or not. Interestingly they probably wouldn’t preface it with ‘physically’. They wouldn’t see the need. And even if you had contributed to this illness, for example through years of heavy drinking, no-one would say that you weren’t actually ill. They might say it was your fault, compared with the non-drinker; but some would relent when they hear that you started drinking following your wife’s tragic death.

Going back to your brain, it is likely to be as vulnerable to life’s misfortunes as any other organ. If a liver can malfunction, then so can a brain, even if we don’t always know exactly what has gone wrong. It would be very bizarre if this didn’t ever happen. But other stuff happens to us, too, life is ever-present with its joys and blows, and these will also influence at every level. The question of whether mental illness is caused by biology, or by life’s traumas is not particularly difficult to answer – surely it must be both. An unusually wired brain, infection, inflammation, childhood abuse, a harsh environment and many other factors may come together to manifest as mental illness. Perhaps there is more biological basis to illnesses like schizophrenia, and more environmental to post traumatic stress disorder; but nothing operates in a vacuum. Life is never black and white.

In fact it would be oddly arrogant to think our brains could not get ill, that we can control them in a way that we cannot control the rest of our bodies. But there often is an expectation that we can, or should. Sometimes mental health professionals will refer to a patient’s distress as behavioural, but what does this actually mean? We behave as a consequence of what has happened to us, both inside our bodies and out of them. We behave to cope with our distress. Behaviour is what we do.

The confusion worsens when we look at the role of psychiatry. As psychiatrists, we are doctors, so we tend to follow a medical model, this is how we have been trained. The problem arises at least partly because we do not decide who is mentally ill. I don’t mean that we don’t assess people and make diagnoses; but by the time they come to see us, this has often been assumed, and they are presenting with mental illness. There is a great plethora of distress out there, but distress doesn’t always equal mental illness. It may do, and it may contribute to its development, but it is not always the same. Consider the physical analogy of over-exercise. This may make your body hurt, but is not illness – although it may lead to you developing arthritis in the future.

The need to reduce suffering is there, but psychiatrists only have a small range of interventions available to them. For someone whose unhappiness might be relieved by better housing, giving an antidepressant may not help. Society encourages the recognition of mental distress, but does not have the resources or ability to provide the solutions. Neither drugs nor talking therapies can solve many of the problems that we see.

As a psychiatrist with a mental illness, the question of its reality exposes some of the cracks in my thinking. I believe in mental illness, and in distress and unhappiness, but I still find it hard to appreciate that I have one myself. Sometimes I think it is because I think my life has not been hard enough; but my illness model tells me that can’t be right. Is there something about the human condition that makes it impossible for us to see ourselves as subject to an illness that might change our thinking? Perhaps a certain egotism, or disbelief that we can lose control? Even when this has happened to me, I can’t believe it will happen again. But then it’s normal to forget pain, both physical and mental, because how could we live otherwise?

It is likely that in future we will have a better understanding of the brain, why it does what it does, and why it goes wrong. This will be of great benefit to those suffering from mental illness, and may offer them validation and effective treatments. It will undoubtedly reduce stigmatisation for them. But what will then happen to those with distress? This cannot be underestimated, and may often be at least as bad as illness. The danger, if we had tests for mental illness, would be that many people might test negative. If we don’t, as a society, recognise distress and its complex relationship with mental illness, then many people will be lost and devalued. At best, they may lose their sick benefit, at worst their whole belief in themselves.

Ultimately, it is partly down to definitions, but also to the need for a compassionate society. Mental illness is real, but so is unhappiness, and they are both multifactorial. Definitions are also important for our view of ourselves. In my view mental illness does need to be tightened up, to protect people from wrong diagnoses and treatments, that may be harmful; but this must not be done in a way that punishes those who do not fit this narrower definition. They are not to blame.