Weight Loss for Sleep ApneaTuesday, February 24, 2009
Obstructive sleep apnea (OSA) is one of the most common respiratory problems in overweight and obese individuals. The poor quality of life, daytime somnolence, fatigue, memory loss, and increased risk for metabolic and cardiac complications makes OSA a significant health problem. Habitual snoring, witnessed apneas, or excessive daytime sleepiness should always prompt further investigation for OSA in anyone with overweight or obesity.
While more severe forms of OSA often require continuous positive airway pressure ventilation, milder forms may be amenable to even modest weight loss (higher degrees of weight loss resulting from bariatric surgery virtually cure OSA).
The effect of dietary weight loss was now for the first time tested in a randomized controlled trial in a new study just out in the American Journal of Respiratory and Critical Care Medicine.
In this study, Henri Tuomilehto and colleagues from the University of Kuopio, Finland, randomized 72 consecutive overweight patients (BMI 28-40) with mild OSA to a very low calorie diet (VLCD=600-800 KCal for 12 weeks) with supervised lifestyle counseling vs. routine lifestyle counseling (general oral and written information about diet and exercise).
While the VLCD group lost about 10% of their initial weight, the control group lost around 3%. The VLCD intervention resulted in a 75% reduced risk for OSA at the end of the year-long study. OSA was objectively cured in 63% of patients in the intervention group, but only 35% of patients in the control group. As expected, improvements in the apnea-hypopnea index (AHI) were strongly associated with changes in weight and waist circumference.
This study demonstrates that weight loss induced by a hypocaloric diet together with lifestyle counseling is feasible and effective in reducing symptoms in in the majority of subjects with mild OSA and that these outcomes are maintained at 1-year follow-up.
Indeed, these findings are very similar to the previous report of marked improvements in OSA in patients achieving an approximately 10% weight loss with sibutramine and lifestyle intervention published by Brendon Yee and colleagues from the University of Sydney in the International Journal of Obesity (2007).
Overall it appears that even a moderate 5-10% weight loss can lead to remarkable improvements in OSA – certainly an intervention worth considering prior to investing in an expensive CPAP machine.