Health psychology

Health psychology is concerned with understanding human behaviour in the context of health, illness, and health care. It is the study of the psychological factors, which determine how people stay healthy, why they become ill, and how they respond to illness and health care. Health psychology has emerged as a separate discipline in the past 30 years and there are many reasons for its rapid development. An important background factor is the major change in the nature of health problems in industrialized societies during the twentieth century. Chronic illnesses such as heart disease and cancer have become the leading causes of death, and behavioural factors such as smoking, diet, and stress are now recognized as playing a major role in the aetiology and progression of these diseases. The provision of health care has grown enormously and there is an increased awareness of good communication as a central ingredient of medical care and of the importance of such factors as patient satisfaction and quality of life as key outcomes in evaluating the efficacy of medical interventions. Although health psychology has developed over a similar time period to general hospital/liaison psychiatry and shares some common areas of interest, there are some clear differences between these two fields. Liaison psychiatry has a primary focus on hospital patients, particularly those experiencing psychological difficulties in the face of a physical health problem. In contrast, health psychology has a much broader focus on both healthy and ill populations and on the psychological processes that influence their level of health or their degree of adaptation to disease. Whereas health psychology has been mainly concerned with developing explanations based on theory, for health-related and illness-related behaviour, liaison psychiatry has concentrated on the diagnosis and treatment of either unexplained symptoms or psychiatric disorders occurring in people with medical conditions (see the other chapters in Part 5 of this volume). In this chapter we provide an overview of the main themes and areas in health psychology. Four broad areas of behaviour will be reviewed, namely behavioural factors influencing health, symptom and illness behaviour, health care behaviour, and treatment behaviour. Inevitably such an overview is selective and the interested reader should seek out a more comprehensive introductory text or more in-depth accounts of specific areas.