There are multiple reasons a person might have sleep apnea. Untreated sleep apnea can cause weight gain so chicken/egg issues. I have two family members on the C-pap and one has sleep apnea because she had a cocleal implant and the other one has multiple health issues so it’s unclear why he has sleep apnea. It’s a complex disorder.
My sleep apnea disappeared as soon as I eliminated wheat and gluten from my diet.