Obstructive sleep apnea is a common sleeping condition associated with negative health effects. It is also usually underdiagnosed. It has been observed that dieting helps to relieve this problem initially. The current study examines the extent to which apnea symptoms are improved with a very low calorie diet after one year in obese patients. In this study, 63 middle-aged, obese men with obstructive sleep apnea went on a very low-calorie diets for nine weeks. The severity of the disorder was measured by the apnea-hypoapnea index, and at the baseline value averaged to 36 events per hour. After the diet period, the events reduced by 21 and the weight by 40 lbs. on an average. After one year, the severity of obstructive sleep apnea was reduced by 17 events and the weight was reduced by 26 lbs/ on an average, demonstrating that the improvements were long lasting.
Obstructive sleep apnea is a breathing disorder during sleep caused by the obstruction of upper airways. Breathing stops for seconds at a time without the knowledge of the person. This disorder impacts health negatively, as it affects cognition and quality of life. The main treatment for obese patients suffering from sleep apnea is weight loss. It is found that 60 to 70 percent patients with sleep apnea are obese. Given the co-occurrence of obesity and sleep apnea, the relationship between obesity and sleep apnea was examined in this study. Men with obesity and sleep apnea disorder were put on a very low-energy diet for nine weeks. The treatments showed positive results with significant improvement in sleep apnea. This study evaluates the positive results seen in initial improvements in the apnea-hypoapnea index in obese patients. These patients, with moderate to severe obstructive sleep apnea, maintained a very low-energy diet for one year after the study. This study is a one-year “pooled observational follow-up of a previously published randomized trial.”
This study selected 63 obese men aged 30 to 65 years having obstructive sleep apnea of severity of at least 15 events per hour. These men underwent a nine-week long very low-calorie diet period. Later, for 43 weeks, these men underwent weight maintenance based on group therapy each month. The severity of the disorder was checked by the apnea-hypopnea index based on the number of times breathing was interrupted per hour at the baseline, after nine weeks and 52 weeks. The effects on body measurements, metabolic syndrome, diabetes, and blood pressure were measured at the baseline, after nine weeks and 52 weeks. Data were analyzed statistically using mean values and standard deviations.
* The results showed that after the diet, the participants with severe problems showed more improvement than those with milder sleep apnea.
* The very low-calorie diet resulted in an overall reduction in body measurement like percentage of body fat, weight and waist circumference.
* The times sleep was interupted per hour and the measure of severity improved significantly after the diet. More improvement was observed in the participants with a higher baseline severity than in those with moderate levels.
* Those who lost more weight showed larger improvement in the times sleep was interupted after one year.
* The general health of the participants showed lasting improvement after the diet, though adverse side effects like gallstones and kidney stones were also observed.
The study was conducted on participants, all of whom were subjected to a diet. No control experiment was done and so the natural progression of the severity of the disease could not be determined accurately. The machine used for recording disturbances during sleep was different from that used as a standard. Moreover, the results cannot be stretched to include younger or older men, women, or people with extreme obesity.
The study conducted on middle-aged men with weight as well as sleep disorders showed that improvements seen after a very low-energy diet last for at least a full year. It was found that men who had the most severe problems with obstructive sleep apnea showed the most improvement after the nine-week-long diet regimen. In addition, those men who lost more weight showed much improvement in sleeping. In this study, 6 out of 63 men were completely cured of the disorder, while 30 men needed no more mechanical intervention for breathing in sleep. Side effects like gallstones are a possibility and must be discussed before going on a very low-energy diet treatment.
For More Information:
Longer-term Effects of Very Low Energy Diet on Obstructive Sleep Apnea: A Cohort Study
Publication Journal: British Medical Journal, 2011
By Kari Johansson, PhD; Erik Hemmingsson, PhD; Karolinska Institute, Stockholm, Sweden
*FYI Living Lab Reports Are Summaries of the Original Research.