Conclusion
Although the biological etiology of dysthymia is inconclusive, the evidence of abnormalities in physiological levels in patients, successful treatment of dysthymia and ineffectiveness of most psychotherapy do strongly suggest a biological substrate in dysthymia. And this factor may interact with psychological, social and environmental factors to lead to the onset and maintenance of dysthymia or increase the vulnerability to dysthymia. As early treatment is more effective, level of of certain physiological levels may serve as prediction or identification of dysthymia as the symptoms of dysthymia are normally not obvious enough to be noticed and considered as dysthymic disorders. If there were a biological factor presence, it would be of not much help to seek psychotherapy alone. And dysthymia certainly largely affect the quality of our life. Nevertheless, the support for biological etiology of dysthymia is growing and more research or studies should be further conducted on determining the biological substrate and discovering antidepressants that have no or less side effects.
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