My husband has very bad sleep apnea, but he does not have Parkinson's. The down side to having sleep apnea is you do not sleep well, so you are tired during the day. For years, I wanted my husband to go for a sleep study because of his snoring, but he would not go. Finally it got so bad that he would fall sleep many times a day- while sitting at the breakfast table reading the paper, while having a conversation with someone, and while driving. That is what got him to go for the sleep study- he got scared when he started to doze off when driving. When he got his CPAP machine, he loved it immediately. He could sleep like he never had before and he could stay awake during the day. Now he cannot sleep at all without his machine. If he goes anywhere overnight and forgets his machine it is a big problem.