Accessibility and adherence to positive airway pressure treatment in patients with obstructive sleep apnea: a multicenter study in Latin America.

PURPOSE: Information on access and adherence to positive airway pressure (PAP) treatment is lacking at the regional level in Latin America. This study characterized access and adherence to PAP in patients with moderate-severe obstructive sleep apnea (OSA) in Latin America. METHODS: Cross-sectional study, conducted at 9 sleep centers across Argentina, Brazil, Chile, Colombia, Mexico, and Peru. Adults diagnosed with moderate-severe OSA (apnea-hypopnea index [AHI] ≥ 15/h) in the previous 12-18 months were eligible. Anthropometrics, health coverage, and OSA severity data were collected. Data on access to therapy, barriers to access, adherence, and factors related to non-compliance were obtained via standardized telephone survey. RESULTS: Eight hundred eighty patients (70% male, 54 ± 13 years, AHI 49 ± 28/h, body mass index 32 ± 7 kg/m2) were included. Four hundred ninety patients (56%) initiated PAP, 70 (14%) discontinued therapy during the first year (mainly due to intolerance), and 420 (48%) were still using PAP when surveyed. Health insurance was private in 36.9% of patients, via the social security system in 31.1%, and via the state in 13.3%, and 18.7% did not have any coverage; 49.5% of patients had to pay all equipment costs. Reasons for not starting PAP were unclear or absent indication (42%), coverage problems (36%), and lack of awareness of OSA burden (14%). Patients with better adherence were older (55.3 ± 13 vs 52 ± 13; p = 0.002) and had more severe OSA (AHI 51.8 ± 27 vs 45.6 ± 27; p = 0.001). CONCLUSIONS: Less than half moderate-severe OSA patients started and continue to use PAP. Unclear or absent medical indication and financial limitations were the most relevant factors limiting access to therapy.

Can We Assess Pulsus Paradoxus through Polysomnography in a Patient with Chronic Obstructive Pulmonary Disease and Sleep-Disordered Breathing?

ABSTRACT: Pulsus paradoxus (PP) is a decrease in systolic blood pressure greater than 10 mm Hg during inspiration that occurs in various medical conditions. Using polysomnography pulse oximetry signal, photoplethysmography variations of the amplitude of the pulse pressure within the respiratory cycle were observed. There is a proportional relationship between the changes of inspiratory waveform values and the generated PP. A 59-year-old male underwent polysomnography that showed sleep hypoxemia, obstructive sleep-disordered breathing (apnea hypopnea index [AHI] = 5.1and respiratory disturbance index [RDI] = 87.9), with variations of pulse pressure induced primarily by inspiration. The highest variations in the pulse wave were observed in NREM sleep during obstructive respiratory events and in biocalibration during nasal breathing. The lowest variations occurred after the correction of inspiratory obstructive events and during biocalibration when asked to hold his breath.

Effectiveness of home single-channel nasal pressure for sleep apnea diagnosis.

INTRODUCTION: Home single-channel nasal pressure (HNP) may be an alternative to polysomnography (PSG) for obstructive sleep apnea (OSA) diagnosis, but no cost studies have yet been carried out. Automatic scoring is simpler but generally less effective than manual scoring. OBJECTIVES: To determine the diagnostic efficacy and cost of both scorings (automatic and manual) compared with PSG, taking as a polysomnographic OSA diagnosis several apnea-hypopnea index (AHI) cutoff points. METHODS: We included suspected OSA patients in a multicenter study. They were randomized to home and hospital protocols. We constructed receiver operating characteristic (ROC) curves for both scorings. Diagnostic efficacy was explored for several HNP AHI cutoff points, and costs were calculated for equally effective alternatives. RESULTS: Of 787 randomized patients, 752 underwent HNP. Manual scoring produced better ROC curves than automatic for AHI < 15; similar curves were obtained for AHI ≥ 15. A valid HNP with manual scoring would determine the presence of OSA (or otherwise) in 90% of patients with a polysomnographic AHI ≥ 5 cutoff point, in 74% of patients with a polysomnographic AHI ≥ 10 cutoff point, and in 61% of patients with a polysomnographic AHI ≥ 15 cutoff point. In the same way, a valid HNP with automatic scoring would determine the presence of OSA (or otherwise) in 73% of patients with a polysomnographic AHI ≥ 5 cutoff point, in 64% of patients with a polysomnographic AHI ≥ 10 cutoff point, and in 57% of patients with a polysomnographic AHI ≥ 15 cutoff point. The costs of either HNP approaches were 40% to 70% lower than those of PSG at the same level of diagnostic efficacy. Manual HNP had the lowest cost for low polysomnographic AHI levels (≥ 5 and ≥ 10), and manual and automatic scorings had similar costs for higher polysomnographic cutoff points (AHI ≥ 15) of diagnosis. CONCLUSION: Home single-channel nasal pressure (HNP) is a cheaper alternative than polysomnography for obstructive sleep apnea diagnosis. HNP with manual scoring seems to have better diagnostic accuracy and a lower cost than automatic scoring for patients with low apnea-hypopnea index (AHI) levels, although automatic scoring has similar diagnostic accuracy and cost as manual scoring for intermediate and high AHI levels. Therefore, automatic scoring can be appropriately used, although diagnostic efficacy could improve if we carried out manual scoring on patients with AHI < 15. CLINICAL TRIALS INFORMATION: Clinicaltrials.gov identifier: NCT01347398.