Hi,If you are aware there is a risk of death associated with your health concern, you could become anxious about dying in your sleep and eventually develop somniphobia.
According to your weight you are falling in to obesity and you may be suffering from sleep apnea.
Other reasons can be
Generalized anxiety
Stress related issues etc.
You have to consult with a physician for your
health checkup and find out whether your problem is due to some medical condition.
Psychological conditions like depression, Eating disorder,can cause obesity.
Physical problems and mental problems are interconnected.
Next Steps
Consult with a psychologist and get help to deal with anxiety, other psychological problems if any.
CBT
Exposure therapy
Self care skills etc are helpful
Health Tips
Eat healthy, Reduce the intake of
sugar, Exercise daily, Follow good sleep hygiene.