Mental health

Mental health is sometimes defined as an absence of a particular illness.

It is better to describe mental health as the person having particular ways of thinking or behaviour that help them to feel good and to maintain how they feel on a daily basis.

The World Health Organisation (WHO) states: "Mental health is an integral and essential component of health."

The WHO constitution states: "Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity." An important consequence of this definition is that mental health is described as more than the absence of mental disorders or disabilities.

Mental health is a state of well-being in which an individual realizes his or her own abilities, can cope with the normal stresses of life, can work productively and is able to make a contribution to his or her community. In this positive sense, mental health is the foundation for individual well-being and the effective functioning of a community.

Reference: World Health Organisation

Mental illness

Typically, we talk about mental health problems or mental illness.

We define mental illness as a person having particular symptoms or behaviour that represents certain types of illnesses that psychiatrists or psychologists may diagnose.

A mental illness typically results in a disruption in a person's thinking, feeling, moods, behaviour and ability to relate to others.

Mental illness is defined in specific ways in legislation.  The legislation varies according to States and Countries.

In this module we are defining mental illness as a person

• having particular symptoms or behaviour
• that represent certain types of illnesses that psychiatrists or psychologists diagnose.

Types of mental health problems after a traumatic brain injury

Types of mental illnesses after a traumatic brain injury include:

a) Mood disorders
b) Psychotic disorders
c) Anxiety disorders
d) Personality & behaviour disorders

Each of these can be diagnosed by a psychiatrist or psychologist.

 

Rates of psychiatric illness: in the community

The rate of psychiatric illness varies quite substantially from one study to another. Some of the factors that influence this are how the psychiatric illness was diagnosed and what patient population was being assessed.

If patients are sampled in the community for the incidence of psychiatric illness then the rate of psychiatric illness will be less. If we assess the rate of psychiatric illness in the clinical population or an inpatient population the rate of psychiatric illness will be significantly higher. If assessments of psychiatric illness are based on questionnaires then the rate of disorder and disability is often higher than if a structured clinical interview is used. The purpose of the structured clinical interview is to provide a clear assessment or diagnosis based on rigid criteria.  This will lower the incidence of the disorder because the threshold to become a case is higher than when a questionnaire is used.

Rates of psychiatric illness: in people who have a brain injury

The rate of psychiatric illness in general is probably two to three times that of the normal population.

For example, the rate of depression in the normal population at any point in time is about 3%, but for people with brain injury the rate of depression can be anything from 12% to 25% depending on the criteria. In some studies the rate of depression is even higher for example, when rating scales are being used.

The same is true for schizophrenia, for the anxiety disorders and the personality disorders.

For people with brain injury there is a significantly higher rate of psychiatric illness than that in the general population. If a person has a number of pre-injury vulnerability factors such as a past history or a family history then the rate is higher again.

Damage to the cerebral hemispheres can cause psychiatric illness

Damage to the cerebral hemispheres can cause psychiatric illness. There have been a number of studies comparing the rate of psychiatric illness in people who have a brain injury comparing that with orthopaedic controls, spinal injury patients and patients with an equal degree of physical disability as a person with a traumatic brain injury. The rate of psychiatric illness is always greater in those individuals who have damage to the central nervous system.

Interrelationship between psychiatric illness and traumatic brain injury

Someone who has pre-injury established diagnosis of a bipolar disorder,  then has a brain injury, can have a substantially changed presentation. Their response to management may also be significantly changed.