CPAP Adherence, Mortality, and Progression-Free Survival in Interstitial Lung Disease and OSA.

BACKGROUND: OSA, a common comorbidity in interstitial lung disease (ILD), could contribute to a worsened course if untreated. It is unclear if adherence to CPAP therapy improves outcomes. RESEARCH QUESTION: Does adherence to CPAP therapy improve outcomes in patients with concurrent interstitial lung disease and OSA? STUDY DESIGN AND METHODS: We conducted a 10-year retrospective observational multicenter cohort study, assessing adult patients with ILD who had undergone polysomnography. Subjects were categorized based on OSA severity into no/mild OSA (apnea-hypopnea index score < 15) or moderate/severe OSA (apnea-hypopnea index score ≥ 15). All subjects prescribed and adherent to CPAP were deemed to have treated OSA. Cox regression models were used to examine the association of OSA severity and CPAP adherence with all-cause mortality risk and progression-free survival (PFS). RESULTS: Of 160 subjects that met inclusion criteria, 131 had OSA and were prescribed CPAP. Sixty-six patients (41%) had no/mild untreated OSA, 51 (32%) had moderate/severe untreated OSA, and 43 (27%) had treated OSA. Subjects with no/mild untreated OSA did not differ from those with moderate/severe untreated OSA in mean survival time (127 ± 56 vs 138 ± 93 months, respectively; P = .61) and crude mortality rate (2.9 per 100 person-years vs 2.9 per 100 person-years, respectively; P = .60). Adherence to CPAP was not associated with improvement in all-cause mortality risk (hazard ratio [HR], 1.1; 95% CI, 0.4-2.9; P = .79) or PFS (HR, 0.9; 95% CI, 0.5-1.5; P = .66) compared with those that were nonadherent or untreated. Among subjects requiring supplemental oxygen, those adherent to CPAP had improved PFS (HR, 0.3; 95% CI, 0.1-0.9; P = .03) compared with nonadherent or untreated subjects. INTERPRETATION: Neither OSA severity nor adherence to CPAP was associated with improved outcomes in patients with ILD except those requiring supplemental oxygen.

New Approaches to Positive Airway Pressure Treatment in Obstructive Sleep Apnea.

Continuous positive airway pressure (CPAP) is a mainstay of therapy in patients with obstructive sleep apnea (OSA). This technology has gone through tremendous changes that resulted in devices that can recognize and differentiate sleep-disordered breathing events, adjust their output to these events, monitor usage, and communicate with the treatment team. This article discusses recent developments in treatment of OSA with PAP.

The complex sleep apnea resolution study: a prospective randomized controlled trial of continuous positive airway pressure versus adaptive servoventilation therapy.

INTRODUCTION: Prior studies show that adaptive servoventilation (ASV) is initially more effective than continuous positive airway pressure (CPAP) for patients with complex sleep apnea syndrome (CompSAS), but choosing therapies has been controversial because residual central breathing events may resolve over time in many patients receiving chronic CPAP therapy. We conducted a multicenter, randomized, prospective trial comparing clinical and polysomnographic outcomes over prolonged treatment of patients with CompSAS, with CPAP versus ASV. METHODS: Qualifying participants meeting criteria for CompSAS were randomized to optimized CPAP or ASV treatment. Clinical and polysomnographic data were obtained at baseline and after 90 days of therapy. RESULTS: We randomized 66 participants (33 to each treatment). At baseline, the diagnostic apnea-hypopnea index (AHI) was 37.7 ± 27.8 (central apnea index [CAI] = 3.2 ± 5.8) and best CPAP AHI was 37.0 ± 24.9 (CAI 29.7 ± 25.0). After second-night treatment titration, the AHI was 4.7 ± 8.1 (CAI = 1.1 ± 3.7) on ASV and 14.1 ± 20.7 (CAI = 8.8 ± 16.3) on CPAP (P ≤ 0.0003). At 90 days, the ASV versus CPAP AHI was 4.4 ± 9.6 versus 9.9 ± 11.1 (P = 0.0024) and CAI was 0.7 ± 3.4 versus 4.8 ± 6.4 (P < 0.0001), respectively. In the intention-to-treat analysis, success (AHI < 10) at 90 days of therapy was achieved in 89.7% versus 64.5% of participants treated with ASV and CPAP, respectively (P = 0.0214). Compliance and changes in Epworth Sleepiness Scale and Sleep Apnea Quality of Life Index were not significantly different between treatment groups. CONCLUSION: Adaptive servoventilation (ASV) was more reliably effective than CPAP in relieving complex sleep apnea syndrome. While two thirds of participants experienced success with CPAP, approximately 90% experienced success with ASV. Because both methods produced similar symptomatic changes, it is unclear if this polysomnographic effectiveness may translate into other desired outcomes. CLINICAL TRIALS: Clinicaltrials.Gov NCT00915499.

Clinical heterogeneity of patients with complex sleep apnea syndrome.

BACKGROUND: The definition of complex sleep apnea (CompSAS) encompasses patients with obstructive sleep apnea (OSA) who develop central apnea activity upon restitution of airway patency. Presence of arterial hypertension (HTN), coronary artery disease (CAD) and heart failure (HF) have been proposed as risk factors for CompSAS among OSA patients. Using our database of patients with CompSAS, we examined the prevalence of these risk factors and defined other clinical characteristics of patients with CompSAS. METHODS: Through retrospective search of the database, we examined the medical and clinical characteristics of consecutive patients diagnosed with CompSAS between 11/1/2006 and 6/30/2011 at NorthShore University HealthSystem. RESULTS: One hundred and fifty patients with CompSAS were identified. Among patients included in the study, 97 (64.7 %) had at least one risk factor for CompSAS, while 53 (35.3 %) did not have any of them. Prevalence of low left ventricular ejection fraction and hypocapnia were low. Therapeutic interventions consisted of several positive airway pressure therapies, mainly adaptive servo ventilation. A hundred and ten patients (73.3 %) complied with recommended therapy and improved clinically. CONCLUSIONS: Although most patients with CompSAS have cardiac comorbidities, about one third of patients do not have any risk factors of CompSAS prior to sleep testing. Further research on factors involved in development of CompSAS will allow for better tailoring of therapy to pathophysiology involved in an individual case.

Pulmonary nocardiosis in a patient with chronic obstructive pulmonary disease--case report and literature review.

Nocardiosis is an infrequent but potentially serious pulmonary infection that typically affects patients with immune suppression or structural lung disease. We report a case of a 70-year-old patient with chronic obstructive pulmonary disease (COPD) treated with inhaled steroids, theophylline, short-acting beta-agonists and anticholinergics, and long-term oxygen therapy, who presented with non-resolving pneumonia. Following a diagnosis of nocardiosis, made based on sputum culture, the patient was treated with trimethoprim/sulphamethoxazole and then, due to treatment side effects, with minocycline. We review the literature data on nocardiosis in COPD patients.

Treatment of complex sleep apnea syndrome.

Complex sleep apnea syndrome (CompSAS) describes the coexistence or appearance and persistence of central apneas or hypopneas in patients with obstructive sleep apnea upon successful restoration of airway patency. We review data on treatment of CompSAS with CPAP, bilevel positive airway pressure, and adaptive servoventilation and discuss evidence for the addition of medications (analgesics, hypnotics, acetazolamide) and gases (oxygen, CO2) to positive airway pressure therapy. Future research should focus on defining outcomes in patients with CompSAS and allow for more accurate tailoring of therapy to the pathophysiology present in the individual patient.

The emergence of central sleep apnea after surgical relief of nasal obstruction in obstructive sleep apnea.

By the current definition, complex sleep apnea (CompSA) refers to the emergence of central sleep apnea (CSA) during the treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP). However, new-onset CSA has been described with use of other treatments for OSA, including tracheostomy, maxillofacial surgery, and mandibular advancement device. We present a patient with CSA beginning after endoscopic sinus and nasal surgery for nasal obstruction in the setting of mild OSA. This case highlights the importance of non-PAP mechanisms in the pathogenesis of CompSA.

Trials of bilevel positive airway pressure - spontaneous in patients with complex sleep apnoea.

INTRODUCTION: Patients with complex sleep apnoea (CompSAS) have obstructive sleep apnoea and experience persistent central apnoeas when exposed to positive airway pressure. Elevated loop gain is one of the postulated mechanisms of CompSAS. We speculated that bilevel positive airway pressure - spontaneous (BPAP-S), by producing relative hyperventilation, may more readily produce CompSAS activity than continuous positive airway pressure (CPAP). If found to do so, a trial of BPAP-S might be a simple way of identifying patients with elevated loop gain who are at risk for CompSAS. MATERIALS AND METHODS: Thirty-nine patients with complex sleep apnoea were included in the study. Segments of NREM sleep on CPAP and BPAP-S matched for body position and expiratory airway pressure (comparison pressure) were retrospectively analysed. Correlations between clinical and demographic variables and polysomnographic response to CPAP and BPAP-S were sought. RESULTS: There was no difference in any of the polysomnographic indices on CPAP and BPAP-S. In 19 patients the use of CPAP was associated with lower AHI at the comparison pressure; in 20 patients the opposite was true. No clinical variables correlated to the differential response to CPAP vs. BPAP-S. CONCLUSIONS: BPAP-S was not more effective than CPAP in stimulating complex sleep apnoea activity.

Comparison of two servo ventilator devices in the treatment of complex sleep apnea.

OBJECTIVE: Servo ventilation (SV) devices generate positive airway pressure with a variable pressure support that changes in response to a patient's own respiratory output. Two currently available SV devices-VPAP-AdaptSV® and BIPAP-AutoSV®-have been used in treatment of complex sleep apnea (CompSAS), but no side-by-side comparisons are available. METHODS: Data of 76 consecutive patients with complex sleep apnea, who were prescribed a VPAP-AdaptSV® or BIPAP-AutoSV® in a non-randomized parallel design, were retrospectively analyzed. Patients underwent a diagnostic polysomnogram followed by a continuous positive airway pressure (CPAP) titration and a SV titration study. Objective compliance with the device was assessed at the first visit at 4-6weeks of its use. RESULTS: Thirty-five patients received a VPAP-AdaptSV® device, while 41 patients were treated with BIPAP-AutoSV®. Patients treated with BIPAP-AutoSV® had a significantly higher apnea-hypopnea index during their CPAP titration study than patients treated with VPAP-AdaptSV® [49/h (28-60) vs. 35/h (19.5-49.5), median (interquartile range), p<0.001]. On follow-up, 56 patients (73.7%) were using their device. Mean nightly use was 5.0h (2.8-6.4) for VPAP-AdaptSV® group and 6.0h (3.5-7.2) for BIPAP-AutoSV® group (p=0.081); an improvement in Epworth Sleepiness Scale score was higher in the BIPAP-AutoSV® group than in the VPAP-AdaptSV® group [4 (1-9) vs. 2.5 (0-5), p=0.02]. CONCLUSION: Our retrospective data indicate that the two servo-ventilation devices are comparable means of controlling complex sleep apnea, and the compliance with them is high.

Eosinophilic pleural effusion complicating allergic bronchopulmonary aspergillosis.

Allergic bronchopulmonary aspergillosis (ABPA) is primarily a disease of patients with cystic fibrosis or asthma, who typically present with bronchial obstruction, fever, malaise, and expectoration of mucus plugs. We report a case of a young man with a history of asthma who presented with cough, left-sided pleuritic chest pain and was found to have lobar atelectasis and an eosinophilic, empyematous pleural effusion. Bronchoscopy and sputum cultures grew Aspergillus fumigatus, and testing confirmed strong allergic response to this mold, all consistent with a diagnosis of ABPA. This novel and unique presentation of ABPA expands on the differential diagnosis of eosinophilic pleural effusions.

Complex sleep apnea unmasked by the use of a mandibular advancement device.

According to most accepted definitions, complex sleep apnea syndrome (CompSAS) is described as an emergence of central apneas in a patient with obstructive sleep apnea (OSA) upon introduction of continuous positive airway pressure therapy (CPAP). We present two patients who developed comparable central apnea activity when treated with either a CPAP device or a mandibular advancement device. As similar findings have been previously documented in patients with OSA treated with maxillofacial surgery or tracheostomy, we propose that the current definition of CompSAS should broaden to include diagnosis of CompSAS in non-PAP-treated patients, who are managed with either a dental appliance or a surgical procedure.

Marked improvement of heart failure upon adequate titration of continuous positive airway pressure in a patient with obstructive sleep apnea.

Sleep disordered breathing (SDB) is frequently present in heart failure (HF), and it may take the form of obstructive (OSA) and central (CSA) sleep apnea. The use of continuous positive airway pressure (CPAP) in patients with OSA and HF is associated with an improved neuroendocrine profile and cardiac function. The degree of upper airway obstruction and the airway closing pressure (and the PAP pressure used to relieve it) may all be highly variable in a setting of uncontrolled HF, mostly due to variable airway oedema. We present a case of a man with HF whose cardiac symptoms radically improved after adequate treatment of his OSA with an auto-adjusting PAP device.

Coma with absent brainstem reflexes resulting from zolpidem overdose.

Zolpidem is a nonbenzodiazepine hypnotic with a favorable adverse effect profile. There are single reports of respiratory decompensation associated with zolpidem overdose. We report a case ofa young woman with depression who developed deep coma with respiratory failure and a loss of brainstem reflexes as a result of zolpidem overdose. Supportive management led to a complete recovery of neurologic function. Acute zolpidem overdose should be considered in the differential diagnosis of coma with absent brainstem reflexes.

Dysphonia and chest pain as presenting symptoms of pneumomediastinum.

Spontaneous pneumomediastinum (SPM) is a rare but generally benign condition characterized by the presence of free air in the mediastinal space that is unrelated to trauma or medical procedure. We describe a case of a 25-year-old woman who presented to the emergency room with a chief complaint of dysphonia, and chest pain. An X-ray of the neck and CT of the chest were performed and showed findings consistent with a pneumomediastinum. Supportive treatment led to an uneventful recovery. We discuss the differential diagnosis of the coexisting chest pain and dysphonia in the diagnosis of SPM.