While anxiety and depression (the affective disorders) are the most common type of mental illness, there are other 'psychoses' that occur less frequently, are more misunderstood, and more akin to the layman's view of 'madness'.
Mood disturbance isn't usually a prominent feature of psychotic illness, but those affected have problems relating to thought processes and their perception of reality. Hallucinations, delusions and fragmented thought patterns are common symptoms, and patients rarely have any insight into their illness.
Schizophrenia
This is perhaps the most misunderstood of all mental illnesses. Because the name can be translated as 'split personality', it is often, wrongly, perceived that this is an illness where the sufferer has a 'Jekyll and Hyde' type of behaviour.
There are between two and four new cases of schizophrenia per 1,000 people each year. The cause isn't known, but it is thought to have a genetic background. The illness most commonly starts in the late teens or early twenties. Auditory hallucinations (hearing voices) is a common symptom. Patients may hear their own thoughts spoken out loud, or may hear other voices talking to them or talking about them.
Delusions are another manifestation of this condition. These are abnormal beliefs that occur due to distorted judgement, for example believing that the neighbours can hear conversations or that someone is planning to set fire to your house. Where the delusions involve a perception that someone is trying to harm you, either physically or emotionally, these are called paranoid delusions, and the type of schizophrenia in which these symptoms predominate is labelled paranoid schizophrenia.
Schizophrenics often have jumbled thought processes, with rapid switches from one subject to another, with no obvious connection between the subjects. They may withdraw from social situations, and their behaviour may become increasingly eccentric. Vagrancy is a common consequence of untreated schizophrenia. There are a number of drug treatments available, but relapse rates are high - around 70%.
Manic depressive illness
This describes an condition where episodes of severe depression alternate with episodes of 'mania'. These swings are interspersed with periods of normal behaviour. It has more recently been renamed 'bipolar affective disorder', as many sufferers have recurrent episodes of one or other mood disturbance, without swinging to the other extreme. The depressive episodes arise for no obvious reason, and are severe.
Mania describes a persistently high or euphoric mood, which is out of keeping with circumstances. Those affected have delusions of grandeur and commonly also suffer from hallucinations. They are overactive and often don't sleep for days at a time. Their behaviour becomes disinhibited, and they commonly go on spending sprees, buying things that they have no need for and cannot afford. They often have an increased appetite and increased libido. Often their mood is very labile, and they can become hostile if their behaviour is challenged.
Bipolar affective disorder can be very effectively treated with medications known as 'mood stabilisers', of which lithium is probably the best known.
Obsessive compulsive disorder (OCD)
Around 2% of people will develop OCD at some point in their lives, and minor obsessional conditions are much more common than this. The condition is more common in women, and tends to start in early adult life.
Patients have often had symptoms for years before they seek medical help, and often it is a relative or friend who reports the problem.
The common experiences are obsessional thinking, with recurrent, persistent thoughts or impulses that cause anxiety or distress. This leads to compulsive behaviours, with repetitions and rituals. The thoughts and rituals commonly relate to hygiene, germs and illness. Repetitive hand washing and an inability to touch certain objects for fear of contamination are common manifestations of OCD. Other obsessions and compulsions revolve around tidiness and orderliness.
The sufferer of OCD recognises that the thoughts are self-generated, that they are illogical, and that the behaviours are abnormal, but they are powerless to resist them. In patients with severe OCD, the symptoms can be extreme and can take over everyday living.
This condition can be treated with a combination of medication and a particular form of psychotherapy known as CBT (cognitive behaviour therapy).
What symptoms should always be assessed medically?
While some patients with mild or self-limiting mood problems will get better without seeing a doctor, there are certain symptoms that are indicative of a significant mental illness and which should always trigger a visit to the doctor.
These include hallucinations, which can be visual (seen) or auditory (heard), delusions, paranoia, symptoms of mania, profound depression, suicidal thoughts, and disruptive obsessions or compulsions.
