Nocturnal Polysomnography without Technical Supervision in the Diagnosis of Respiratory Sleep Disorders, Diagnostic Performance of Home and Sleep Laboratory Studies.

Introduction Unattended Polysomnography (type 2 PSG) is a procedure for the diagnosis of sleep-disordered breathing (SDB). Published evidence on its performance and efficacy is limited. Available studies reveal a high rate of lost records that could limit its application. Objective To assess the efficacy of type 2 PSG and the rate of studies that must be repeated due to critical loss of signals. Methods prospective, descriptive study. Adult patients with suspected SDB were included. Unattended PSG was performed using portable equipment. 75 patients were connected at home and another 75 in the laboratory, without subsequent monitoring. Records were evaluated to determine the percentage of the night with adequate quality for each of the signals, considered as an evaluable signal for = 70% of the total recording time (TRT). The need to repeat the studies was also estimated. Results: 150 patients were recruited; 44% women; age 57.3 ± 15.4 years; BMI 29.4 ± 6.5. EEG and EOG signals were adequate in 149 records. Flow signal by pressure cannula was adequate in 146 and by thermistor in 67.8%. In only one study the signal of both effort bands were inadequate. Oximetry was lost in 4 cases. Ten tracings (6%) met the criteria for repetition; 8 hospital and 2 home. Conclusions Acceptable records were obtained in most unattended PSG studies, both at home and in the sleep laboratory. The rate of repetition of studies due to loss of signal was 6%, with failure in SaO2 or in flow signals being the main cause of the indication.

Access to CPAP treatment in patients with moderate to severe sleep apnea in a Latin American City.

INTRODUCTION: The most effective treatment for moderate to severe obstructive sleep apnea (OSA) is continuous positive airway pressure (CPAP) but adherence may be a limiting factor. Most compliance studies often only include patients under CPAP treatment, neglecting the importance of access to treatment. The aim of this study was to evaluate CPAP access and compliance in OSA patients, after CPAP indication and titration. METHODS: We included moderate to severe OSA patients, diagnosed by in-lab polysomnography (PSG), with CPAP indication and effective pressure titration. Between 12 to 18 months after treatment was indicated a telephone questionnaire was administered including questions about access to CPAP, reasons of no access, reported adherence and symptoms improvement. RESULTS: A total of 213 patients responded to the survey (171 males, mean age 53.4±13.5 and BMI 34.02±8.8 kg/m2). Almost a third of the patients (28.2%) did not initiate CPAP treatment. Out of 213, 153 patients (71.8%) started treatment with CPAP and 120 (56.3%) reported still being under treatment a year after indication, additionally, 85.8% reported that they were using it =4hs/night. Those who accessed to CPAP were on average, older age, had full coverage of treatment by their medical insurance, required lower effective pressure and experienced more severe sleepiness compared to those individuals who did not accessed to CPAP. DISCUSSION: A significant proportion of OSA patients with CPAP indication did not initiate and/or eventually abandoned CPAP. Approximately only 50% of the patients were still under treatment, with acceptable self-reported adherence rate and clinical response, one year after the initial treatment indication. Additional measures are necessary to increase access to CPAP and improve long-term compliance.