Unfortunately, CPAP does not cure sleep apnea. When in use, it simply controls your symptoms by keeping your airway open while you sleep.
If you stop using CPAP your airway will once again close and you will experience apneas. For most people with sleep apnea, CPAP is a life-long treatment. Weight loss can improve your overall health and may decrease the number of apneas during sleep. The pressure needed to keep your airway open may also decrease, but it is rare to completely stop CPAP treatment.
Your clinician regularly assesses your progress. If your weight changes, your CPAP pressure will be adjusted to ensure effective treatment.