A Link between Writing and Suicidal Tendencies?

From the Economist's obit for HS Thompson:

Economist.com | Obituary: "In 1964 he had made a long journey to Ketchum, Idaho, to the grave of Ernest Hemingway, one of his models and heroes. He wanted to understand why Hemingway had killed himself in his cabin in the woods, and concluded that he had lost his sense of control in a changing world:
It is not just a writer's crisis, but they are the most obvious victims because the function of art is supposedly to bring order out of chaos, a tall order even when the chaos is static, and a superhuman task when chaos is multiplying...So finally, and for what he must have thought the best of reasons, he ended it with a shotgun."