Anxiety and obsessional disorders

In the community, the term ‘anxiety’ is frequently as­sociated with a stressful Western lifestyle and thought of as a modern phenomenon— but this is far from the case. Anxiety disorders were clearly described as early as the writings of Hippocrates, and have been preva­lent in literary characterization to the present. Anxiety disorders are the most common type of psychiatric disorder, with one in three people experiencing them during a lifetime. They are characterized by marked, persistent mental and physical symptoms of anxiety, that are not secondary to another disorder and that impact negatively upon the sufferer’s life. Anxiety dis­orders may be primary psychiatric conditions, or a sec­ondary response to the stress associated with physical illness and its treatment. Many people with anxiety disorders never seek medical attention, but these are commonly seen conditions in both primary and sec­ondary care, and they may present with either mental or physical complaints. Obsessive– compulsive disorder is also considered in this chapter. Its relationship to anxiety disorders is uncertain— classification systems currently separate the two— but there are some important common features. Normal anxiety is the response to threatening situ­ations. Feelings of apprehension are accompanied by physiological changes that prepare for defence or escape (‘fight or flight’), notably increases in heart rate, blood pressure, respiration, and muscle tension. Sympathetic nervous system activity is increased, causing symptoms such as tremor, sweating, polyuria, and diarrhoea. Attention and concentration are fo­cused on the threatening situation. Anxiety is a bene­ficial response in dangerous situations, and should occur in everyday situations of perceived threat (e.g. examinations). Abnormal anxiety is a response that is similar but out of proportion to the threat and/ or is more pro­longed, or occurs when there is no threat. With one exception, the symptoms of anxiety disorders are the same as those of a normal anxiety response. The ex­ception is that the focus of attention is not the external threat (as in the normal response) but the physio­logical response itself. Thus in abnormal anxiety, at­tention is focused on a symptom such as increased heart rate. This focus of attention is accompanied by concern about the cause of the symptom.