Clinical presentation

People with depressive disorders may present with psychological symptoms, but for many the physical symptoms, such as fatigue, weight loss or insomnia, are the main concern. Patients with a coexisting physical illness may find this harder to bear when depressed and may complain about a flare up of physical symptoms. Hypochondriacal concerns are also common. As a result, people with depressive disorder may present to doctors in virtually every branch of medicine.

The symptoms that occur in depressive episodes are described below. Not all these symptoms are used to make a diagnosis and there are differences between ICD10 and DSM4 in the way the condition is classified, as shown in Figure 1. Depressive episodes are categorised as mild, moderate or severe, partly on the basis of the number of symptoms present. Mild episodes usually feature the minimum number of symptoms required to make a diagnosis of depressive episode, and in severe episodes most symptoms are present, with moderate episodes falling somewhere between. However, as was discussed on pages 4–6, the extent to which a person’s life is disrupted by depression is also used to classify the severity of the episode.

Fig. 1 Comparison of diagnostic criteria for depressive episodes in ICD10 and DSM4.

Core symptoms of depression

In ICD 10, three core symptoms of depression are described. As would be expected, one of these is depressed mood, which some patients describe as being the same as normal sadness, but more intense or prolonged, while others say it has a distinct quality, like a dark cloud. There is sometimes a ‘diurnal variation of mood’ in depressive episodes, with the person feeling worse in the morning and improving as the day progresses. The second of the core symptoms is loss of interest and enjoyment. Motivation is reduced. Hobbies cease to be of interest, and previously enjoyable encounters with friends and family may become chores to be avoided. Anhedonia, an inability to experience pleasure, often occurs. The final core symptom is reduced energy leading to increased fatiguability. People with depression can feel too tired to do things, or rapidly become fatigued and have to stop what they are doing.