Cost-effectiveness Study of a Lifestyle Change Program for the Treatment of OSA and Obesity: Hospital-Primary Care.

Intervention group: Intensive weight-loss program: 0-3 months very low calorie diet, 15 days substituting three meals for low calorie shakes, from 15 to 120 days substituting 1 meal and from 120 days to 12 months on a low calorie diet while starting a progressive exercise programme. Recommendations for good sleep habits will be given. The program will be carried out through group and individual sessions with the hospital dietician. After 3 months: group sessions with a nurse in the basic area. Group sessions led by hospital dietician. From 3 to 12 months: group sessions led by primary care nurse.

Patients will be managed according to the usual recommendations: The common written diet (designed by a hospital nutritionist) and an exercise advice will be given according to patient age and level of activity, without any other assessment or additional visits.