The concept Chronic Depression describes the state associated with the clinical symptoms of a Major Depressive Episode, but of lesser intensity, fluctuating and long-lasting in time (more than two years). It is constituted by various disorders: the Major Depressive Episode with symptoms of depression that do not respond or improve sufficiently with the treatment, or the Major Depression Episode partially recovered but with residual symptoms, and a specific disorder independent of the Major Depressive Episode, which is the Dysthymic disorder .
In the new and recent Diagnostic and Statistical Manual of Mental Illnesses (DSM-5, 2013) all of them are classified into a single diagnostic category called Persistent Depressive Disorder. Since this nosological concept is very recent, there is a lack of data and consensus is still insufficient; Therefore, in the present review we will focus on the Dysthymic Disorder , since it is the most studied and the one with the most symptoms, clinical conditions and repercussions it shares with the rest of chronic depressive disorders.
The Dysthymic Disorder is an alteration of the state of mind in which a depressive mood is experienced, which manifests itself with discouragement and decay, fatigue and lack of energy, loss of interest and disappointment, dissatisfaction and very different non-specific fears, difficulties to maintain the attention and concentration and to make decisions, concerns and repetitive and circular thoughts on diverse topics, poor self-concept, with feelings of incompetence or uselessness and high sensitivity to criticism and rejection. The most obvious thing in people who suffer from this disorder is irritability, self-criticism, pessimism and dissatisfaction.. It is frequent the decrease of activity, especially pleasant and leisure related, and those involving relationships with other people, although it is not clear if this is a symptom or a consequence of discomfort. Anxiety is also present in its different forms.
In Europe there are few cases in the general population that is affected by this disorder (Haro JM et al., 2005); in all the investigations carried out, it is confirmed that it affects women in a greater proportion, with a ratio of 2-3 times more than for men. Another important fact is that despite these high percentages, the prevalence for the diagnosis of Major Depressive Disorder is double that for the Dysthymic Disorder.
The psychiatrists and clinical psychologists consider that the symptoms of the Dysthymic Disorder are not as serious as those of a Major Depressive Disorder, because they are more fluctuating and psychological manifestations predominate: cognitive, emotional or affective and related to motivation. In Major Depressive Disorder the symptoms are more biological and motor (inhibition, loss of appetite and weight, early awakening) and involve the "psychophysical claudication", which is a biographical break (Gastó, C., 2001). The patient with Dysthymic Disorder does not feel completely different from what he was before, and although with difficulties, he can continue to maintain his plans and occupations. However, due to its long duration, the symptoms of the Dysthymic Disorder affect all aspects of the life of the sufferer, including his relationships with significant persons, work life and personal well-being .
A very important element of diagnosis for psychiatrists and clinical psychologists is to differentiate mood symptoms that constitute a disorder of affective manifestations derived from normal emotional experiences due to contingencies and life experiences that are unavoidable but have no pathological consideration. The experience of sadness is not the discriminative element of having a depressive disorder; yes it is the absence of reactivity of humor to environmental stimuli and it is also the difficulty to experience satisfaction. Another characteristic differentiating factor is the absence of specific facts that explain the affect of the mood in the case of depressive disorders. Sometimes the symptoms of the disorder manifest themselves coinciding with some stressor or vital event, but the alterations persist beyond the resolution of the conflict or the disappearance of the stressor; even on occasions the facts that for the patient constitute a serious situation, inescapable or irresoluble, are not endorsed by their relatives.