Sustained improvement in mild obstructive sleep apnea after a diet- and physical activity--based lifestyle intervention: postinterventional follow-up

Background: Obesity is the most important risk factor for obstructive sleep apnea (OSA). Weight-reduction programs have been observed to represent effective treatment of overweight patients with OSA. However, it is not known whether beneficial changes remain after the end of the intervention. Objective: The aim of the study was to assess the long-term efficacy of a lifestyle intervention based on a healthy diet and physical activity in a randomized, controlled, 2-y postintervention follow-up in OSA patients. Design: Eighty-one consecutive overweight [body mass index (in kg/[m.sup.2]): 28-40] adult patients with mild OSA were recruited. The intervention group completed a 1-y lifestyle modification regimen that included an early 12-wk weight-reduction program with a very-low-calorie diet. The control group received routine lifestyle counseling. During the second year, no dietary counseling was offered. Change in the apnea-hypopnea index (AHI) was the main objective outcome variable, and changes in symptoms were used as a subjective measurement. Results: A total of 71 patients completed the 2-y follow-up. The mean ([+ or -] SD) changes in diet and lifestyle with simultaneous weight reduction (-7.3 [+ or -] 6.5 kg) in the intervention group reflected sustained improvements in findings and symptoms of OSA. After 2 y, the reduction in the AHI was significantly greater in the intervention group (P = 0.049). The intervention lowered the risk of OSA at follow-up; the adjusted odds ratio for OSA was 0.35 (95% CI: 0.12-0.97; P = 0.045). Conclusion: Favorable changes achieved by a 1-y lifestyle intervention aimed at weight reduction with a healthy diet and physical activity were sustained in overweight patients with mild OSA after the termination of supervised lifestyle counseling. This trial was registered at clinicaltrials.gov as NCT00486746. Am J Clin Nutr 2010;92:688-96. doi: 10.3945/ajcn.2010.29485.