Efeitos da restrição energética sobre a apneia do sono, atividade simpática, estresse oxidativo, biomarcadores inflamatórios, função endotelial, adiposidade corporal, perfil metabólico e pressão arterial em pacientes obesos com apneia obstrutiva do sono

• Ano de defesa: 2014
• Autor(a) principal: Fernandes, Julia Freitas Rodrigues
• Orientador(a): Sanjuliani, Antonio Felipe
• Banca de defesa: Neves, Mário Fritsch Toros , Moreira, Annie Seixas Bello , Diestel, Cristina Fajardo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade do Estado do Rio de Janeiro
• Programa de Pós-Graduação: Programa de Pós-Graduação em Fisiopatologia Clínica e Experimental
• Departamento: Centro Biomédico::Faculdade de Ciências Médicas
• País: BR
• Palavras-chave em Português: Pressão arterial; Perda ponderal; Obesidade; Atividade simpática; Perfil metabólico; Função endotelial; Apneia do sono tipo obstrutiva; Endotélio; Estresse oxidativo
• Palavras-chave em Inglês: Obstructive sleep apnea; Weight loss; Obesity; Sympathetic activity; Metabolic profile; Endothelial function
• Área do conhecimento CNPq: CNPQ::CIENCIAS DA SAUDE::NUTRICAO
• Link de acesso: http://www.bdtd.uerj.br/handle/1/12755

Nutritional intervention for weight loss is one of the treatment options for obstructive sleep apnea (OSA) in patients with excess body adiposity. However, the effects of moderate energy restriction, recommended by current guidelines for the treatment of obesity, on OSA are not yet known. To evaluate the effects of moderate energy restriction on the body adiposity; severity of OSA; blood pressure; sympathetic activity; oxidative stress; inflammatory biomarkers; metabolic profile and endothelial function in obese patients with OSA. Methods: A 16-week randomized clinical trial, involving 21 subjects with obesity (grade I or II), aged 20-55 years and presenting an apnea/hipopnea index (AHI) > 5 events/h. Participants were randomized into 2 groups: 11 in the energy restriction group (ERG) and 10 in the control group (CG). The ERG was instructed to follow an energy-restricted diet (-800 kcal/day) and the CG was advised not to change their food intake. At the beginning and at the end of the study, participants underwent evaluation of: OSA with the equipment Watch- PAT200® including the determination of the following parameters of OSA severity: AHI, minimum O2 saturation, number of O2 desaturations >4%; body adiposity (weight, %body fat and circumferences of waist, hip and neck); blood pressure (BP); sympathetic nervous system activity (plasma levels of catecholamines); inflammatory biomarkers (c-reactive protein and adiponectin); oxidative stress (malondialdehyde); metabolism of glucose (glucose, insulin and HOMA-IR) and lipids (total cholesterol and fractions and triglycerides); and endothelial function (index of reactive hyperemia evaluated by Endo - PAT 2000® and cellular adhesion molecules). The statistical analysis was performed with the software STATA v. 10. The level of statistical significance was p < 0.05. Results: The ERG, compared to the CG, presented significantly greater reduction in body weight (-5.57±1.81 vs. 0.43±1.21kg, p<0.001) and in the others parameters of body adiposity; in AHI (-7.22±2.79 vs. 0.13±1.88 events/h, p=0.04); in the number of O2 desaturation >4% (-33.70±15.57 vs. 1.80 ± 7.85, p=0.04), in plasma concentrations of adrenaline (-12.70±3.00 vs. -1.30±3.90pg/mL, p=0.04); and significantly greater increase in minimum O2 saturation (4.60±1.55 vs. -0.60±1.42%, p=0.03). The ERG, in comparison with the CG, showed a greater decrease, however without statistical significance, in systolic BP (-4.23±1.95 vs. 2.34±1.39mmHg, p=0.05), in insulin levels (-5.11±1.93 vs. -0.65±1.28µU/mL, p=0.07) and HOMA-IR (-1.15±0.49 vs. -0.08±0.33, p=0.09). During the study period, the modifications in total and central adiposity presented a significant correlation with changes in parameters of OSA severity; in systolic and diastolic BP; and in insulin levels and in HOMA-IR, even after adjustments for confounding factors. The changes in central adiposity were significantly associated with modifications in levels of norepinephrine and adiponectin. The changes in parameters of OSA severity presented significant association with the modifications in serum levels of C-reactive protein. This study suggests that in obese patients with OSA moderate energy restriction is able to reduce total and central adiposity, parameters of OSA severity and sympathetic nervous system activity.