Abstract

Sleep disorders are common in a general population. It effect one in 5 adults and has several short term and long term bad side effects on health. Sleep apnea (SA) is the most important and common component of sleep disorders. This paper presents an automatic approach for detecting apnea events by using few bio-singles that are related to breathe defect. This work uses only air flow, thoracic and abdominal respiratory movement as input. The proposed algorithm consists of three main parts which are signal segmentation, feature generation and classification. A new proposed segmentation method intelligently segments the input signals for further classification, then features are generated for each segment by wavelet packet coefficients and also original signals. In classification phase a unique parallel PSO-SVM algorithm is investigated. PSO used to tune SVM parameters, and also data reduction. Proposed parallel structure used to help PSO to search space more efficiently, also avoiding fast convergence and local optimal results that are common problem in similar parallel algorithms. Obtained results demonstrate that the proposed method is effective and robust in sleep apnea detection and statistical tests on the results shown superiority of it versus previous methods even with more input signals, and also versus single PSO-SVM. Using fewer signals means more comfortable to subject and also, reduction of cost during recording the data.

INTRODUCTION

Sleep disorders are important because they are common in a general population; a survey in 1987 [1] reported that at least one symptom of disturbed sleep was present in 41% of all subjects; and still sleep disorder is common now [2], for instance, Young reported that one daytime sleepiness in 5 adults in 2004 [3].

The sleep disorders have several short term and long term bad side effects[4]. Short-term effects lead to impaired attention and concentration, lowered life quality, increased rates of absenteeism with less productivity, and greater possibility of accidents at work, home or on the road. Longterm consequences of sleep deprivation include increased morbidity and mortality from more automobile accidents, coronary artery disease, heart failure, high blood pressure, obesity, type 2 diabetes mellitus, stroke and memory impairment as well as depression. Long-term consequences, however, are still open [5] for further academic research..