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Drug-Induced Sleep Endoscopy DISE with Target Controlled Infusion TCI and Bispectral Analysis in Obstructive Sleep Apnea
Published on: December 6, 2016
Heart rate detrended fluctuation indexes as estimate of obstructive sleep apnea severity
Eduardo Luiz Pereira da Silva1, Rafael Pereira, Luciano Neves Reis
1From the Center of Innovation, Technology, and Education-CITE (ELPS, VLP, LAC, OCB), Camilo Castelo Branco University (UNICASTELO), Sao Jose dos Campos Technology Park, Sao Jose dos Campos; University Iguaçu Campus-V (ELPS), Itaperuna, Rio de Janeiro; Department of Biological Sciences (RP), State University of Southwest Bahia-UESB, Jequie, Bahia; Sleep Institute of Itaperuna (LNR), Rio de Janeiro, Brazil; and Humboldt-Universität zu Berlin (NW), Berlin, Germany.
Abstract:
In the present study, we aimed at investigating a heart rate variability (HRV) biomarker that could be associated with the severity of the apnea-hypopnea index (AHI), which could be used for an early diagnosis of obstructive sleep apnea (OSA). This was a cross-sectional observational study on 47 patients (age 36 ± 9.2 standard deviation) diagnosed with mild (23.4%), moderate (34%), or severe (42.6%) OSA. HRV was studied by linear measures of fast Fourier transform, nonlinear Poincaré analysis, and detrended fluctuation analysis (DFA)—DFA α1 characterizes short-term fluctuations, DFA α2 characterizes long-term fluctuations. Associations between polysomnography indexes (AHI, arousal index [AI], and oxygen desaturation index [ODI]) and HRV indexes were studied. Patients with different grades of AHI had similar sympathovagal balance levels as indicated by the frequency-domain and Poincaré HRV indexes. The DFA α2 index was significantly positive correlated with AHI, AI, and ODI (Pearson r: 0.55, 0.59, and 0.59, respectively, with P < 0.0001). The ROC analysis revealed that DFA α2 index predicted moderate and severe OSA with a sensitivity/specificity/area under the curve of 0.86/0.64/0.8 (P = 0.005) and 0.6/0.89/0.76 (P = 0.003), respectively. Our data indicate that the DFA α2 index may be used as a reliable index for the detection of OSA severity.
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