I go through some intense mood swings, and I've noticed my art takes a darker tone when I'm dealing with intense depression. I take on more personal projects that only involve myself and a muse, and I produce less of my art because it becomes more exhausting to create.
In contrast when I'm experiencing a mania I can take on more client projects and am able to produce higher volumes of work. I stay more organized and am able to orchestrate shoots that require a team to produce.
The problem is that the depression is more common than the mania for me, which is why I believe I've never really been able to take that step into being a full-time career photographer. I still love what I do though and love where it's taken me, and without this outlet I feel like I would be suffering a lot more when dealing with the low-points of my mood swings.