FRIDAY, Dec. 4 (HealthDay News) -- Obese men with obstructive sleep apnea who lost significant weight on a stringent diet markedly reduced the severity of their disease in comparison with a control group that did not diet, according to a study published online Dec. 3 in BMJ.
Kari Johansson, of the Karolinska Institutet in Stockholm, Sweden, and colleagues enrolled 63 obese men (body mass index, 30 to 40) who also had moderate to severe apnea. The group was randomized to receive either a liquid very-low energy diet for seven weeks followed by two weeks during which normal food was reintroduced, or the subject's usual diet during the nine weeks. The primary outcome measure was score on the apnea-hypopnea index (AHI).
By week nine, the researchers found that the diet group had a mean body weight 20 kg lower than the control group, and a mean AHI 23 events/h lower. Seventeen percent of subjects on the diet were free of apnea and 50 percent reported mild disease. In the control group, all but one subject continued to have moderate-to-severe disease. In subgroup analysis, those with the higher baseline AHI in the diet group had the greatest improvement.
"Treatment with a low energy diet improved obstructive sleep apnea in obese men, with the greatest effect in patients with severe disease. Long term treatment studies are needed to validate weight loss as a primary treatment strategy for obstructive sleep apnea," the authors write.
The research was supported in part by Cambridge Manufacturing Company Limited and Novo Nordisk Scandinavia AB.