This article is more than 5 years old. Information may no longer be current.
Calorie restriction improved BP, sleep apnea in obese adults
Calorie restriction may improve BP and obstructive sleep apnea in obese adults, according to findings presented at the American Heart Association’s High Blood Pressure Research Scientific Sessions.
Marcia R. Klein, MD, PhD, and colleagues evaluated the effects of moderate energy restriction on severity of obstructive sleep apnea, BP, sympathetic activity, oxidative stress, inflammation, body adiposity, metabolic profile and endothelial function in adults with obesity and obstructive sleep apnea.
The researchers randomly assigned 21 obese adults aged 20 to 55 years with apnea/hypopnea index ≥5 events/hour to an energy-restriction group or a control group. The energy-restriction group was instructed to reduce intake by 800 calories per day, whereas the control group was instructed not to change daily food intake.
At baseline and 16 weeks, participants were evaluated for obstructive sleep apnea severity parameters, body adiposity, BP, plasma catecholamines, C-reactive protein, adiponectin, malondialdehyde, metabolism of glucose, lipid profile and endothelial function.
Compared with the control group, the energy-restriction group had a greater reduction in body weight (–5.6 kg vs. 0.4 kg; P<.001) and all measures of body adiposity, apnea/hypopnea index (–7.2 events/hour vs. 0.1 events/hour; P=.04), number of O2 desaturation >4% (–33.7 vs. 1.8; P=.04) and plasma adrenaline (–12.7 pg/mL vs. –1.3 pg/mL; P=.04). Compared with the control group, the energy-restriction group also had a greater increase in minimum O2 desaturation (4.6% vs. –0.6%; P=.03).
The researchers observed a trend toward decreased systolic BP (–4.2 mm Hg vs. 2.3 mm Hg; P=.05), insulin (–5.1 mcU/mL vs. –0.7 mcU/mL; P=.07) and homeostasis model assessment of insulin resistance (HOMA-IR; –1.2 vs. –0.08; P=.09) in the energy-restriction group.
Changes in body adiposity correlated with changes in parameters of obstructive sleep apnea severity, BP, insulin, HOMA-IR, norepinephrine and adiponectin, whereas changes in obstructive sleep apnea severity were associated with changes in CRP, according to the researchers.
“This study suggests that in obese patients with obstructive sleep apnea, moderate energy restriction can reduce not only body fat but also the severity of obstructive sleep apnea,” Klein, adjunct professor in the department of applied nutrition at Rio de Janeiro State University, Brazil, said in a press release.
“Moderate energy restriction in these patients has the potential to reduce [CV] risk. Losing weight was most likely the key to all the benefits observed in the calorie-restricted group. A greater reduction in systolic [BP] can be explained, at least partially, by the reduction in body weight that was associated with reduction in obstructive sleep apnea severity and sympathetic nervous system activity,” Klein said.
For more information:
Fernandes JFR. Abstract #461. Presented at: American Heart Association’s High Blood Pressure Research Scientific Sessions; Sept. 9-12, 2014; San Francisco.
Disclosure: The study was funded by Fundação Carlos Chagas Filho de Ampara à Pesquisado do Rio de Janeiro. Klein reports no relevant financial disclosures.