The link does not seem to be working. However, there are many more.
Efficacy of antidepressants for dysthymia: a meta-analysis of placebo-controlled randomized trials. - Abstract - Europe PubMed Central
The conclusion is very clear: "These results support the utility of antidepressants for dysthymic disorder. In fact,
the margin of efficacy of antidepressants for dysthymic disorder was larger than for MDD. Future studies providing longer-term data on the treatment of dysthymic disorder with antidepressants are essential". Antidepressants may be EVEN MORE effective for moderate forms of depression!