Evaluation of telemonitoring of continuous positive airway pressure therapy in obstructive sleep apnoea syndrome: TELEPAP pilot study.

INTRODUCTION: Continuous positive airway pressure is an effective treatment for obstructive sleep apnoea syndrome. However, positive airway pressure compliance rates are disappointingly low, so effective interventions are needed to improve compliance in sleep apnoea. Telemonitoring has been used to improve compliance, but results have been inconsistent. This study aimed to determine outcomes of telemonitoring positive airway pressure compliance and efficacy data compared to usual care and phone-call care. METHODS: Randomized controlled study in which 51 patients (82.4% male; between 25 and 78 years), diagnosed with moderate to severe obstructive sleep apnoea were consecutively randomized to usual care, weekly phone-call care or telemonitored care with the use of Restraxx™. All patients were submitted to a comprehensive educational programme during positive airway pressure adaptation. Patients were followed for the first four weeks of treatment with automatic positive airway pressure (AutoSet Spirit S8®; ResMed), and compliance and efficacy data were analyzed. RESULTS: Telemonitored care group used automatic positive airway pressure an average of 5.0 ± 1.8 hours/night, usual care patients 5.1 ± 2.5 hours and phone-call care patients 3.9 ± 2.6 hours. The residual Apnoea--Hypopnoea Index was 5.3 ± 3.0 in telemonitored care, 5.0 ± 2.5 in usual care and 5.6 ± 3.8 in phone-call care. No statistically significant differences were found between groups regarding positive airway pressure compliance or efficacy (p = 0.296 and p = 0.825, respectively). DISCUSSION: In the presence of a comprehensive educational programme during positive airway pressure adaptation, telemonitoring patients did not show benefits concerning compliance and efficacy. A larger follow-up period is needed to evaluate the long-term results of a telemonitoring programme.

Utility of new-generation pacemakers in sleep apnea screening.

OBJECTIVE: Patients with cardiac pacemakers present a high prevalence of undiagnosed sleep apnea syndrome (SAS). New-generation pacemakers have algorithms that identify sleep respiratory events. Our aim was to evaluate their accuracy in the diagnosis of SAS. METHODS: We performed a prospective study that included patients with new-generation pacemakers (Reply 200 pacemakers). All patients underwent a polysomnography (PSG). On the same night, the respiratory disturbance index of the PSG (RDI-PSG) and of the pacemaker (RDI-PM) were recorded. The agreement between methods was assessed using the kappa coefficient, Bland and Altman statistics and receiver operating characteristic (ROC) curves. RESULTS: Sixty patients were recruited but the RDI-PM for the PSG night was not available in six patients. PSG diagnosed SAS in 74% of patients (20% severe, 19% moderate, 35% mild). Besides snoring (63%), most patients had no SAS symptoms. There was a strong positive correlation between RDI-PSG and RDI-PM (r = 0.522, p < 0.001), but the level of agreement between methods regarding SA diagnosis/severity was poor (k = 0.167). ROC curves identified a RDI-PM of 10 events/h as the optimal cut-off point for diagnosing SAS (area under the curve (AUC): 0.81, sensitivity: 80%, specificity: 79%, positive predictive value: 91%, negative predictive value: 58%). The best cut-off for identifying moderate/severe SAS was at 13 events/h (AUC: 0.86, sensitivity: 100%, specificity: 70%, positive predictive value: 68%, negative predictive value: 100%). CONCLUSIONS: SAS prevalence in patients with pacemakers is high (74%). Most are asymptomatic, which could delay the diagnosis. Patients with clinical indication for a pacemaker may benefit from a device with sleep apnea monitoring.

Effects of CPAP on nitrate and norepinephrine levels in severe and mild-moderate sleep apnea.

BACKGROUND: Reduced plasma nitrate (NO(x)) levels and increased urinary norepinephrine (U-NE) levels have been described in severe obstructive sleep apnea (OSA), and are reverted by continuous positive airway pressure (CPAP). The effect of CPAP on these biomarkers in mild-moderate OSA is not well understood. The aim of this study was to compare NO(x) and U-NE levels and blood pressure (BP) between male patients with mild-moderate and severe OSA and determine the impact of 1 month of CPAP therapy on these parameters. METHODS: We undertook a prospective study of 67 consecutive OSA patients (36 mild-moderate, 31 severe). Measurements of plasma NO(x) at 11 pm, 4 am and 7 am, 24-h U-NE and ambulatory BP were obtained at baseline and after 1 month of CPAP. RESULTS: At baseline, NO(x) levels showed a significant decrease during the night in both groups (p < 0.001). U-NE level and BP were significantly higher in the severe OSA group. After 1 month of CPAP, there was a significant increase in NO(x) levels and a reduction in U-NE level and BP only in patients with severe OSA. CONCLUSIONS: One month of CPAP results in significant improvements in NO(x) levels, 24-h U-NE level and BP in patients with severe OSA, but not in patients with mild-moderate OSA. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01769807.