The symptoms are often not directly caused by a medical illness or by substances, including substance use or other medications. The symptoms may cause significant problems or distress in social, work, academic, or other major areas of life functioning.In children and adolescents, mood can be irritable, and duration must be at least one year, in contrast to two years needed for diagnosis in adults. Early onset (diagnosis before age 21) is associated with more frequent relapses, psychiatric hospitalizations, and more co-occurring conditions. For younger adults with dysthymia, there is a higher co-occurrence in personality abnormalities and the symptoms are likely chronic. However, in older adults with dysthymia, the psychological symptoms are associated with medical conditions and/or stressful life events and losses.Dysthymia can be contrasted with major depressive disorder by assessing the acute nature of the symptoms. Dysthymia is far more chronic (long lasting) than major depressive disorder, in which symptoms may be present for as little as two weeks. Also dysthymia often presents itself at an earlier age than major depressive disorder. Prevention
Though there is no clear-cut way to prevent dysthymia from occurring, some suggestions have been made. Since dysthymia will often first occur in childhood, it is important to identify children who may be at risk. It may be beneficial to work with children in helping to control their stress, increase resilience, boost self-esteem, and provide strong networks of social support. These tactics may be helpful in warding off or delaying dysthymic symptoms. Treatments
Persistent depressive disorder can be treated with psychotherapy and pharmacotherapy.
The overall rate and degree of treatment success is somewhat lower than for non-chronic depression, and a combination of psychotherapy and pharmacotherapy shows best results. Therapy
Psychotherapy can be effective in treating dysthymia. In a meta-analytic study from 2010, psychotherapy had a small but significant effect when compared to control groups. However, psychotherapy is significantly less effective than pharmacotherapy in direct comparisons.There are many different types of therapy, and some are more effective than others. The empirically most studied type of treatment is cognitive-behavioral therapy. This type of therapy is very effective for non-chronic depression, and it appears to be also effective for chronic depression. Cognitive behavioral analysis system of psychotherapy (CBASP) has been designed specifically to treat PDD. Empirical results on this form of therapy are inconclusive: While one study showed remarkably high treatment success rates, a later, even larger study showed no significant benefit of adding CBASP to treatment with antidepressants. Schema therapy and psychodynamic psychotherapy have been used for PDD, though good empirical results are lacking. Interpersonal psychotherapy has also been said to be effective in treating the disorder, though it only shows marginal benefit when added to treatment with antidepressants. Medications
In a 2010 meta-analysis, the benefit of pharmacotherapy was limited to selective serotonin reuptake inhibitors (SSRIs) rather than tricyclic antidepressants (TCA). According to a 2014 meta-analysis, antidepressants are at least as effective for persistent depressive disorder as for major depressive disorder.