Are Poets Crazier than Other People?

If you ask poets, yes. A British study recently recruited 294 poets to answer questionnaires about their mental health, and they reported rates of mental illness significantly higher than the population at large:

two poets (0.7%) reported schizophrenia, 15 reported bipolar disorder (5.1%), 152 reported depression (51.7%) and 80 reported anxiety disorder (27.2%).

Is this real, or are they exaggerating? If they are exaggerating, is it because they are sensitive drama queens, or because they just believe that as poets they ought to be crazy?