Sleep-related breathing disorders in idiopathic pulmonary fibrosis are frequent and may be associated with pulmonary vascular involvement.

PURPOSE: Sleep-related breathing disorders (SRBD) may be associated with a worse prognosis in idiopathic pulmonary fibrosis (IPF). However, the prevalence of sleep disorders in IPF and the pathophysiological link between SRBD and IPF is unclear. PATIENTS AND METHODS: In this prospective trial, consecutive patients with stable IPF underwent polysomnography and cardiopulmonary exercise testing. Epworth sleepiness scale, Regensburg insomnia scale, and Pittsburgh sleep quality index were evaluated. Exclusion criteria were oxygen supplementation therapy, lung emphysema, and heart failure. For pairwise comparison of categorical data, the two-proportion z-test was applied. Correlation between continuous variables was assessed via the Pearson correlation coefficient. Patients without and with SRBD were compared. To find predictors for SRBD in IPF, multivariable logistic regression was applied. RESULTS: A total of 74 IPF patients were evaluated and 45 patients (11 female, median age 74 years, forced vital capacity 71.3%, DLCO 53.9%) were analyzed. Any kind of sleep disorder was found in 89% of patients. SRBD was present in 49% (81% obstructive sleep apnea, 19% central sleep apnea), insomnia in 40%, and periodic leg movements in 47% of subjects. The SRBD subgroup presented with a significantly lower performance (workload(peak)%pred 86.5 vs. 101.0 (p = 0.036); V'O2(AT) 618.5 ml/min vs. 774.0 ml/min (p = 0.043)) and exhibited a significantly higher V'E/V'CO2(peak) of 43.0 l/l vs. 38.5 l/l (p = 0.037). In search of predictors for SRBD by logistic regression, workload(peak)%pred was identified as a significant variable (p = 0.033). CONCLUSIONS: SRBD is frequent in IPF. Pulmonary vascular limitations may represent the pathophysiological link between IPF and SRBD. Workload(peak)%pred may be an independent risk factor for the occurrence of SRBD.

Cardiopulmonary Exercise Testing Allows Discrimination Between Idiopathic Non-specific Interstitial Pneumonia and Idiopathic Pulmonary Fibrosis in Mild to Moderate Stages of the Disease.

It is unclear whether there are cardiopulmonary exercise testing (CPET) parameters which may indicate poor prognosis in the early course of fibrosing interstitial lung disease. 27 untreated consecutive subjects (13 idiopathic non-specific interstitial pneumonia (iNSIP), 14 idiopathic pulmonary fibrosis (IPF); 19 male; age 69 ± 10 years) were enrolled in this observational pilot study. Subjects underwent routine pulmonary function testing and CPET. Statistically, the t test and the Mann-Whitney-U test were applied in the presence of normal and non-normal distribution (according to Shapiro-Wilk), respectively. Analyzing the whole cohort, only mild functional impairments were determined. Comparison of iNSIP and IPF groups detected significant differences for the CPET parameters V'O2Peak[%pred] (p = 0.011), V'O2/kgPeak (p = 0.033), Watt[%pred] (p = 0.048), V'E/V'CO2 (Rest: p = 0.016; AT: p = 0.011; Peak: p = 0.019; Slope: p = 0.040), V'E/V'O2 (Rest: p = 0.033 AT: p = 0.014; Peak: p = 0.035). CPET parameters may indicate IPF-specific impairments even in mild disease. It may be hypothesized that these parameters are early biomarkers of poor prognosis.

Effect of a Heated Breathing Tube on Efficacy, Adherence and Side Effects during Continuous Positive Airway Pressure Therapy in Obstructive Sleep Apnea.

BACKGROUND: Heated breathing tubes were developed to improve heated humidification in continuous positive airway pressure (CPAP) therapy of patients with obstructive sleep apnea syndrome (OSAS). OBJECTIVES: We wanted to investigate the influence of a heated breathing tube on patients' satisfaction with the treatment, the rate of side effects and the adherence to treatment. METHODS: Eighty-eight patients with primarily diagnosed OSAS were treated in a randomized, controlled, single-blind trial for 12 months either with a CPAP system plus conventional heated humidifier or with a CPAP system plus heated humidifier and an integrated heated breathing tube. RESULTS: Both systems improved the respiratory disturbances and the quality of sleep in a similar manner. The difference in the overall satisfaction with the treatment (subscale 3 of the visual analogue scale) between the two treatment groups was not statistically significant (mean difference -14.1, 95% CI -28.7 to 0.6; p = 0.059). The rate of side effects and the quality of life did not differ significantly between the two groups. The patients with the heated breathing tube used the treatment on average 1 h longer, but this was not statistically significant (4.96 ± 1.95 vs. 3.90 ± 2.54 h/night; p = 0.06). CONCLUSIONS: Controlled heated breathing tube humidification as compared to conventional heated humidification improves neither the adherence to treatment, nor the rate of side effects, nor the quality of life in nonselected OSAS patients.

Long-term therapy with continuous positive airway pressure in obstructive sleep apnea: adherence, side effects and predictors of withdrawal - a 'real-life' study.

BACKGROUND: Long-term adherence to positive airway pressure (PAP) treatment is essential in patients with obstructive sleep apnea syndrome (OSAS). OBJECTIVES: The aim of the present study was to analyze treatment adherence under real-life conditions and factors associated with discontinuation of PAP therapy. METHODS: Patients newly diagnosed with OSAS and started on PAP therapy were contacted by telephone after a minimum of 1 year. Side effects, quality of life, subjective treatment adherence and Epworth Sleepiness Scale (ESS) scores were assessed. Objective treatment adherence was calculated by reading the built-in run time counter of the PAP device. Anthropometric parameters, level of education, apnea-hypopnea index (AHI), ESS score and the type of PAP therapy prescribed at the time of the first stay in the sleep lab were collected retrospectively. RESULTS: Median follow-up was 13 months (range 7-18 months). Of 303 patients (69 female, 234 male) available for this study, 191 patients (63%) still used the PAP device regularly ('users'), while 83 (27.4%) had definitively discontinued PAP treatment ('nonusers'). In the nonusers group, 29 patients (34.9%) discontinued PAP treatment within the first 3 months. In the users group, subjective PAP usage was 6.6 ± 1.5 h/night and objective adherence was 4.7 ± 2.3 h/night. Objective nightly use of PAP treatment correlated significantly with baseline AHI (r = 0.13, p = 0.041) but not with sex, age, body mass index, ESS score or education level. Patients with a low AHI and ESS score and patients without a coexisting medical condition or with more than two comorbidities tended to discontinue PAP therapy more frequently. CONCLUSIONS: PAP treatment adherence has to be optimized in OSAS patients. When initiating PAP therapy, clinicians have to focus on those patients at risk for discontinuing treatment. Education sessions and closer follow-up are possible strategies to improve treatment adherence and to avoid treatment discontinuation.

Evaluation of a system for transcutaneous long-term capnometry.

BACKGROUND: The measurement of CO(2) partial pressure (PCO(2)) is of great importance. Former systems of transcutaneous capnometry combining the measurement of oxygen partial pressure (PO(2)) and PCO(2) had their limitations due to skin irritations caused by the heating-up of the sensor and a short application time of 4 h. OBJECTIVES: To evaluate for the first time combined monitoring of transcutaneous PCO(2) (tcPCO(2)) and oxygen saturation applying a lower temperature (sensor temperature 42 degrees C) and a new sensor technology in healthy individuals during sleep. METHODS: Twenty-nine healthy individuals [12 males, age 35.2 +/- 17.0 years, body height: 170.2 +/- 12.0 cm (mean +/- SD), weight: 76.3 +/- 15.8 kg, body mass index 26.5 +/- 5.4] were monitored for more than 6 h at night with the TOSCA 500 instrument (Radiometer, Basel, Switzerland). tcPCO(2) was continuously monitored and its correlation with selective measured capillary PCO(2) values (PcapCO(2)) was monitored at 0.00 and 4.00 h. RESULTS: At 0.00 h, PcapCO(2) was 37.1 +/- 5.1 mm Hg and tcPCO(2) was 43.4 +/- 6.6 mm Hg (p < 0.001). At 4.00 h, PcapCO(2) was 37.0 +/- 5.6 mm Hg and tcPCO(2) was 43.5 +/- 5.4 mm Hg (p < 0.001). PcapCO(2) and tcPCO(2) were positively and significantly correlated (0.00 h: r = 0.5, p < 0.02 and 4.00 h: r = 0.72 and p < 0.001) at both time points. In the course of the night, there was no significant drift in the tcPCO(2) values. CONCLUSION: The investigated system enables stable measurement of tcPCO(2) without relevant drift in healthy individuals and does not require recalibration. tcPCO(2) is highly suitable as a measure of PcapCO(2) because the two parameters are highly correlated and there is no inconvenience to the patient.

Comparison of manual titration and automatic titration based on forced oscillation technique, flow and snoring in obstructive sleep apnea.

BACKGROUND: Continuous positive airway pressure (CPAP) treatment in obstructive sleep apnea syndrome (OSAS) requires pressure titration usually performed during attended in-hospital polysomnography. This manual titration procedure is not well standardized. The aim of the study was to ascertain whether a new automatic titration device is as effective as standard manual titration in determining constant CPAP pressure. METHODS: We included 38 patients with a newly diagnosed OSAS. Participants were randomly assigned to attended in-laboratory manual titration and automatic titration in two consecutive nights. Fixed CPAP pressure was set at the optimal pressure determined during the second night. The follow-up period was 6 weeks. Main outcomes were apnea/hypopnea index (AHI) and Epworth sleepiness scale (ESS). RESULTS: AHI (manual: baseline 40.5+/-21.5/h vs. treatment 6.4+/-3.3/h (p<0.001); automatic: 53.3+/-28.1/h vs. 7.8+/-3.3/h (p<0.001)) and ESS (manual: 11.3+/-4.7 vs. 8.8+/-5.1 (ns); automatic: 11.5+/-5.6 vs. 7.0+/-3.8 (p<0.05)) showed a similar improvement in both groups. Pressure recommendation by the device and the technician, although not statistically different (8.7+/-2.9 vs. 9.0+/-3.3 mbar), corresponded only in 50% of the patients. CONCLUSIONS: Automatic titration effectively predicts constant CPAP pressure for long-term treatment when performed during an attended polysomnography. Careful evaluation of raw data and polysomnography recording is mandatory before choosing a fixed CPAP pressure after automatic titration.

Comparison of automatic and continuous positive airway pressure in a night-by-night analysis: a randomized, crossover study.

BACKGROUND: Long-term compliance is suboptimal in the treatment of the obstructive sleep apnea syndrome (OSAS). OBJECTIVES: We compared the efficacy of and the adherence to automatic continuous positive airway pressure (APAP) and constant continuous positive airway pressure (CPAP) based on a night-by-night analysis. METHODS: We performed a randomized, single-blind crossover study in 20 patients with moderate-to-severe OSAS. After diagnostic polysomnography and manual titration, patients were treated for 8 weeks with both constant CPAP and APAP in random order. Compliance and leakage were analyzed night by night using the software LOGSoft of the Magellan iPAP device. RESULTS: The reduction in the apnea/hypopnea index (baseline 32.9 +/- 19.1/h, CPAP 4.6 +/- 2.9/h, APAP 5.6 +/- 3.6/h; p < 0.001 compared to baseline) and the Epworth Sleepiness Scale (baseline 10.3 +/- 5.7, CPAP 6.6 +/- 4.8, APAP 4.9 +/- 4.6; p < 0.001 compared to baseline) did not significantly differ between the treatment modes. Leakage time and compliance per night were not statistically different (leakage CPAP 31 +/- 57 min, APAP 25 +/- 49 min; compliance CPAP 383 +/- 116 min, APAP 382 +/- 107 min). There was no correlation between leakage and compliance. Thirteen patients (65%) preferred APAP at the end of the study. CONCLUSIONS: Treatment efficacy and adherence are similar with CPAP and APAP. There is a trend towards lower leakage with APAP therapy. Patients prefer the automatic mode to fixed pressure.

Anticyclic modulated ventilation versus continuous positive airway pressure in patients with coexisting obstructive sleep apnea and Cheyne-Stokes respiration: a randomized crossover trial.

BACKGROUND: Although coexisting obstructive sleep apnea (OSA) and Cheyne-Stokes respiration (CSR) occur frequently in patients with heart diseases, optimal treatment remains unclear. Positive airway pressure (PAP) effectively treats OSA and adaptive servo-ventilation (ASV) has been shown to improve CSR. We compared a new treatment algorithm combining automatic continuous positive airway pressure (APAP) and ASV (anticyclic modulated ventilation, ACMV) versus continuous positive airway pressure (CPAP). METHODS: Thirty-nine patients (35 male, four female; aged 65.5±9.7 years; body mass index, 31.0±5.9 kg/m2) with underlying heart disease and coexisting OSA and CSR were enrolled. After diagnostic polysomnography (PSG) and CPAP titration, patients were randomized either to CPAP or to ACMV for four weeks of treatment in a crossover design. RESULTS: Total apnea-hypopnea index (AHI) was 49.0±18.8/h at baseline, 12.3±14.6/h with CPAP (P<0.001 vs baseline), and 3.7±5.6/h with ACMV (P<0.001 vs. baseline and vs. CPAP). Obstructive AHI was 20.7±14.4/h at baseline, 5.1±9.3/h with CPAP (P<0.001 vs. baseline), and 0.4±0.4/h with ACMV (P<0.001 vs. baseline and vs. CPAP). Central AHI was 28.3±13.4/h at baseline, 7.2±9.7/h with CPAP (P<0.001 vs baseline) and 3.3±5.4/h with ACMV (P<0.001 vs. baseline and vs. CPAP). Ejection fraction was increased significantly (from 38.6±15.6 to 44.4±12.2%) only with ACMV. Subjective sleepiness significantly improved only with CPAP whereas objective sleep quality and treatment adherence were not different between both treatment modalities. CONCLUSION: ACMV is an effective treatment option in patients with coexisting OSA and CSR. It is superior to CPAP in reducing total AHI as well as obstructive and central AHI.

Long-term auto-servoventilation or constant positive pressure in heart failure and coexisting central with obstructive sleep apnea.

BACKGROUND: The coexistence of obstructive sleep apnea (OSA) and central sleep apnea (CSA) and Cheyne-Stokes respiration (CSR) is common in patients with heart failure (HF). While CPAP improves CSA/CSR by about 50%, maximal suppression is crucial in improving clinical outcomes. Auto-servoventilation (ASV) effectively suppresses CSA/CSR in HF, but few trials have been performed in patients with coexisting OSA and CSA/CSR. Our objective was to evaluate a randomized, controlled trial to compare the efficacy of ASV and CPAP in reducing breathing disturbances and improving cardiac parameters in patients with HF and coexisting sleep-disordered breathing. METHODS: Both modes were delivered using the BiPAP autoSV (Philips Respironics) over a 12-month period. Seventy patients (63 men, 66.3 ± 9.1 y, BMI 31.3 ± 6.0 kg/m(2)) had coexisting OSA and CSA/CSR, arterial hypertension, coronary heart disease, or cardiomyopathy and clinical signs of heart failure New York Heart Association classes II-III. Polysomnography, brain natriuretic peptide (BNP), spiroergometry, and echocardiography were performed at baseline and after 3 and 12 months of treatment. RESULTS: Both modes of therapy significantly improved respiratory disturbances, oxygen desaturations, and arousals over the study period. ASV reduced the central apnea hypopnea index (baseline CPAP, 21.8 ± 11.7; ASV, 23.1 ± 13.2; 12 months CPAP, 10.7 ± 8.7; ASV, 6.1 ± 7.8, P < .05) and BNP levels (baseline CPAP, 686.7 ± 978.7 ng/mL; ASV, 537.3 ± 891.8; 12 months CPAP, 847.3 ± 1848.1; ASV, 230.4 ± 297.4; P < .05) significantly more effectively as compared with CPAP. There were no relevant differences in exercise performance and echocardiographic parameters between the groups. CONCLUSIONS: ASV improved CSA/CSR and BNP over a 12-month period more effectively than CPAP.