Weight Loss Driver of Sleep Apnea Improvements

Bariatric Surgery Vs Dieting & Exercise

posted by Bariatric Skinny Editorial Team
filed under Bariatric Surgery postings

Researchers in Melbourne, Australia have concluded a study that has shown that conventional weight loss programs are no less effective than bariatric surgery at reducing sleep apnea.  It is the weight loss itself that matters and not how the individual lost the weight.  Bariatric surgery is very effective at helping the obese shed extra weight and one of the added benefits of that weight loss is its positive effect on sleep apnea, but the study has shown that losing weight via conventional means (i.e. dieting and exercise) is just as beneficial in reducing sleep apnea symptoms.

Obstructive sleep apnea (OSA) is highly prevalent in obese individuals.  According to a New England Journal of Medicine published report entitled, The Occurrence of Sleep-Disordered Breathing among Middle Aged Adults, it is estimated that OSA is seen in 42% to 48% of obese men and between 8% and 38% of obese women.  Studies on weight loss after bariatric surgery, as detailed in the report Bariatric Surgery: a Systematic Review and Meta-Analysis, which was published in the Journal of the American Medical Association, have indicated patient remission rates of OSA can be as high as 60% and 80%.  The effectiveness of weight loss on reducing sleep apnea symptoms is apparent; however, the Melbourne study set out to determine whether bariatric surgery weight loss is more effective than conventionally reduced body weight at reducing sleep apnea symptoms.

The Melbourne study was led by Dr. John B. Dixon of the Baker IDI Heart and Diabetes Institute in Melbourne, Australia.  It consisted of 60 participants, recruited between September of 2006 and March of 2009, which were split into two groups of 30.  The first group followed a conventional weight loss program that consisted of consultations with a dietician and physician, very low calorie diets that resulted in a daily deficit of 500 calories, walking and 200 minutes per week of other fitness activities.  The second group underwent Lap-Band surgery or laparoscopic adjustable gastric band surgery.  To qualify for the study, the patients had to have a body mass index of 35 to 55 and an apnea-hyponea index (AHI) of 20 events per hour or more that was diagnosed within the last six months.

The study analyzed the change in body weight and AHI from the beginning to the 2-year mark, with AHI being the primary statistic for the study objective.  The patients in the conventional weight loss group lost a mean of 5.1 kg of body weight and saw AHI decrease by 14 events per hour.  The surgery group had a much larger mean weight loss of 27.8 kg and an AHI decrease of 25.5 events per hour.  

Study analysis by the researchers resulted in the conclusion that AHI will decrease with weight loss, but that moderate levels of weight loss appear to account for most of the benefit.  There appears to be decreasing benefit on AHI events as weight loss levels increase beyond modest amounts.  It was thus concluded that, although bariatric surgery leads to significant weight loss, it does not appear to statistically improve sleep apnea symptoms better that weight loss achieved via conventional methods such as dieting and exercise.

Source: The Journal of the American Medical Association

From the Message Boards