I'm not a psychiatrist, but we know that they're both related. Depression, particularly from a volume perspective, is related more to suicide than has been post-traumatic stress disorder, in our experience. PTSD in particular is affected by lack of sleep, more so than depression. One of the symptoms of depression sometimes is excessive sleep, an inability to get up.
The burden of depression is greater in absolute numbers. Prevalent in mental health illness in the Canadian Forces is depression. As I mentioned earlier, our 2002-03 Statistics Canada mental health survey of the armed forces found that regular force males, in the armed force data, almost doubled the depression rate of the general public. It's a major concern for us.