Anxiety may keep you up at night, but mania takes away the need for sleep. Anxiety makes you cautious of things, mania will throw you into wild situations. When you're anxious, you are aware of your heart beating fast and your breathing becoming laboured, mania makes you too high to notice. Anxiety is very distinct from mania. People aren't often hospitalized for anxiety, but mania is very often a cause for it. Mania shares some symptoms with anxiety but they are almost always accompanied by symptoms not associated with anxiety. At least that's how I understand it.