Are Lower Heart Rate, Dizziness And Weakness While Sleeping A Cause For Concern?

My 59 year old son occasionally experiences some concerning symptoms when he is sleeping. His heart rate goes as low as 50 at times. He experiences dizziness and a feeling of weakness. He doesn t have insurance, was laid off last year. I know this is vague, but this has been happening for a while now. he s depressed about the lay off . If this means any thing that I can help him with, I certainly want to. Thank you