Recognising Depression

Prevalence: Depression ranks fourth in importance of all causes of disease burden for the population of the planet and third in women. In the economically developed countries, depression rises to second place. Depressive disorders are common, occurring in all countries, at all ages, in both sexes and often in conjunction with other illnesses. Depression is a recurrent and potentially chronic and disabling condition. If a person has one episode of depression, he or she has a 50% chance of having another one, a 70% chance of another episode after two episodes, and a 90% chance after three episodes. If untreated, a depressive episode can last for 6 months or more. One in six people with chronic Depression commit suicide. These figures show how important it is to recognise and treat Depression.

The overall life-time risk of having a depressive episode is approximately 15% but the risk is not equal for everyone. The principal risk factors for the occurrence of depression and the risk factors associated with a poor prognosis have been determined.

Diagnosis: Despite its prevalence, depression is under-diagnosed and consequently under-treated. This is partly because depressed mood is often considered by many to be a character weakness and a natural response to negative events. Feelings of sadness or despondency are part of normal human emotion and may be the consequence of disappointments or failures. Clinically, however, depression denotes a disorder of mood that is distinct from normal emotions. This distinction is not always easy to appreciate which makes diagnosis so difficult.

Furthermore there is a considerable hesitation for patients to consult. There is often an important time lag between the first appearance of symptoms and a consultation with a primary care phycisian or a psychiatrist. The reasons for this delay and the final motive for a consultation make interesting reading.

Characteristics of depression: Although Depression is characterised by low mood, it is the sustained, pervasive feeling of misery, despair and hopelessness are the predominant features of depressive illness which differentiate it from normal feelings of unhappiness or sadness. Defining depression involves distinguishing it from normality by identifying a series of signs and symptoms.The most used diagnostic criteria are those of the Diagnostic and Statistical Manual (DSM-IV), the International Clinical Diagnostic criteria (version 10) (ICD-10) and the Beck Depression Inventory (BDI). These diagnostic criteria should not be confused with Depression rating scales such as the Hamilton Depression Rating Scale (HDRS) and Montgomery and Asberg Depression Rating Scale (MADRS) which are designed to measure the severity of the depressive symptoms. The core symptoms of are defined in the fourth edition of the DSM (DSM-IV).