Predictors of Mortality in Pulmonary Hypertension-Associated Chronic Lung Disease.

Background/Objectives: Pulmonary hypertension (PH) often accompanies chronic lung diseases. Several chronic lung diseases with PH portends unfavorable outcomes. We investigated which variables in this cohort of patients with chronic lung disease and PH predicts mortality. Methods: This is a retrospective analysis of patients with chronic lung disease and PH at a single tertiary, academic center. The underlying lung disease included were COPD, IPF, other fibrotic ILD, non-fibrotic ILD, fibrotic sarcoidosis, and CPFE. All patients had right heart catheterization diagnostic of PH as well as pulmonary function testing data including 6 min walk testing. Univariable and multivariate Cox regression was performed to identify variables associated with mortality. Results: We identified 793 patients with chronic lung disease and PH. In total, 144 patients died prior to potential lung transplant. In multivariable Cox regression IPF, other fibrotic ILD, non-fibrotic ILD, and CPFE were significantly associated with an increased risk of mortality. Severe PH (PVR > 5 WU), FEV1 < 30% predicted, FVC < 40% predicted, 6 min walk distance < 150 m were also significantly associated with an increased risk of mortality. Conclusions: Carrying a diagnosis of IPF, CPFE, fibrotic ILD, or non-fibrotic ILD with PH has an increased risk of mortality as compared to COPD with PH. Hemodynamic, PVR > 5 WU, 6 min walk test less than 150 m, as well as spirometric data including FEV1 < 30% and FVC < 40% predicted were independently associated with an increased risk of death.

Sarcoidosis-associated pulmonary hypertension.

PURPOSE OF REVIEW: Pulmonary hypertension is a serious complication of sarcoidosis. This review discusses clinical characteristics of patients with sarcoid-associated pulmonary hypertension (SAPH) and pitfalls in the diagnosis, and highlights potential therapies. RECENT FINDINGS: SAPH is common in patients with advanced disease, but it can occur in patients with minimal disease burden. Risk factors for SAPH include restrictive lung physiology, hypoxemia, advanced Scadding chest X-ray stage, and low carbon monoxide diffusion capacity. Echocardiogram is a good initial screening tool in the diagnosis of pulmonary hypertension, but right heart catheterization is necessary to confirm the diagnosis. Treatment with pulmonary vasodilators, including endothelin antagonists, can lead to improvements in pulmonary hemodynamics in some patients but may not improve their exercise capacity. Forced vital capacity is an important predictor of exercise performance in patients with SAPH. Clinical observations and response to specific therapies for pulmonary hypertension suggest the presence of different SAPH phenotypes. SUMMARY: Patients who complain of persistent dyspnea should be screened for the presence of pulmonary hypertension. The prognosis of SAPH is poor and it is prudent to consider referral of these patients for lung transplantation. In some patients with SAPH, treatment with anti-inflammatory agents and pulmonary vasodilators can lower pulmonary arterial pressures, improve dyspnea and functionality, and enhance overall quality of life.

Unexpected pulmonary mechanics during positive pressure mechanical ventilation in fibrotic lung disease with concomitant flail chest.

Understanding of pulmonary mechanics is essential to understanding mechanical ventilation. Typically, clinicians are mindful of peak and plateau pressures displayed on the ventilator and lung compliance, which is decreased in lung disease such as idiopathic pulmonary fibrosis (IPF). Decreased lung compliance leads to elevated peak and plateau pressures. We present a patient with IPF undergoing mechanical ventilation after cardiac arrest. Despite low lung compliance, he had normal peak and plateau pressures due to the presence of flail chest and increased chest wall compliance. This case highlights the role chest wall compliance plays in total respiratory system compliance and pulmonary mechanics.

Physiologic correlates of sleep quality in severe emphysema.

BACKGROUND: Sleep quality is poor in severe emphysema. We hypothesized that in addition to nocturnal oxygen desaturation, the severity of airflow obstruction and degree of thoracic hyperinflation are responsible. METHODS: Twenty-five patients (14 males, 64 ± 6 [ ± SD] yrs, BMI 24.7 ± 4.2 kg/m(2)) with severe emphysema (FEV(1) = 28 ± 8% predicted, TLC = 125 ± 14% predicted) were studied. Measurements included spirometry, lung volumes, arterial blood gas, length of the diaphragm's zone of apposition (LZAP) and a polysomnogram. RESULTS: Total sleep time (TST) was 227 ± 93 minutes with a sleep efficiency (SE) of 56 ± 21%. The mean SaO(2), lowest SaO(2), and% TST with a SaO(2) < 90% were 90 ± 5%, 83 ± 8% and 29 ± 40%, respectively. TST correlated with FEV(1)% (r = 0.5, p = 0.02), FVC% (r = 0.4, p = 0.03) and LZAP (r = 0.5, p = 0.01). SE correlated with FEV(1)% (r = 0.5, p = 0.02) and LZAP (r = 0.5, p = 0.01), but not with FVC% (r = 0.4, p = 0.07). Additionally, TST and SE correlated negatively with residual volume% (r = -0.4, p = 0.046, and r = -0.4, p = 0.03, respectively). There was no correlation between TST and SE and measures of nocturnal oxygenation. Multiple linear regression was used to predict TST, with 50% (r(2) = 0.49) explained by a combination of LZAP (27%), mean SaO(2) (23%), and the lowest SaO(2) (< 1%). To predict SE, 44% (r(2) = 0.43) was explained by a combination of LZAP (29%), mean SaO(2) (14%), and the lowest SaO(2) (1%). CONCLUSION: Although parameters of respiratory function and mechanics correlate with sleep quality, both nocturnal oxygenation and measurements of respiratory function/mechanics predict sleep quality in severe emphysema.

Effect of Triple Therapy with Budesonide-Formoterol-Tiotropium Versus Placebo-Tiotropium on Sleep Quality in Patients with Chronic Obstructive Pulmonary Disease.

BACKGROUND: Factors responsible for poor sleep quality in patients with chronic obstructive pulmonary disease (COPD) includes the effects of medications. This study evaluates the effect of the inhaled triple therapy of budesonide-formoterol-tiotropium versus placebo-tiotropium on sleep quality in COPD patients. METHODS: Twenty-three patients (11 [48%] males; age 55 [51-60, 48--5] years; body mass index [BMI] 25 [22-30, 18-40] kg/m2; forced expiratory volume in 1 second [FEV1]1.10 [0.80 -1.90, 0.60-2.80] L, 42 [31-62, 24-75] % predicted) were studied. Ten patients were randomized to budesonide-formoterol-tiotropium and 13 patients to placebo-tiotropium. At baseline and after 28 days, patients completed spirometry, polysomnography, an Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), COPD-specific St George's Respiratory Questionnaire (SGRQ-C) and short form 36 (SF 36). RESULTS: After 28 days, there was a significant 29% increase in the bedtime FEV1 in the budesonide-formoterol-tiotropium group (from 0.75 [0.55-1.30, 0.50-2.40] L to 1.00 [0.75-1.55, 0.50-3.00] L, p=0.031), with no change in the placebo-tiotropium group (from 1.20 [0.80-1.50, 0.60-1.90] L to 1.15 [0.75-1.55, 0.50-1.80] L, p=0.91). No significant change was found post treatment in sleep efficiency or total sleep time in both the budesonide-formoterol-tiotropium group (from 78 [72-92, 62-98]% to 88 [77-92, 40-98]%, p=0.70 and 290 [268-358, 252-382] min to 342 [303-358, 157-372] min, p=0.77, respectively) and the placebo-tiotropium group (from 82 [75-88, 46-93]% to 84 [77-87, 62-94]%, p=0.96 and 320 [292-350, 180-378] min to 339 [303-349, 241-366] min, p=0.79, respectively). While there was no significant change in the arousal index in the budesonide-formoterol-tiotropium group (9 [5-16, 0-48] arousals/hour to 14 [9-17, 2-36] arousals/hour, p=0.43), a significant increase was seen in the placebo-tiotropium group (11 [4-13, 3--2] arousals/hour to 17 [11-21, 2-33] arousals/hour, p=0.027). Similarly, there was no change in the ESS in the budesonide-formoterol-tiotropium group (6 [3-8, 0-11] to 6 [5-8, 0-1]), p=0.44), but a marginally significant increase in the placebo-tiotropium group (8 [5-12, 2-18] to 10 [7-13, 5-18], p=0.07), with a significant difference in the ESS 28 days post treatment between the 2 groups (6 [5-8, 0-11] versus 10 [7-13, 5-18], p=0.043). There was no significant change in nocturnal oxygenation, sleep architecture, PSQI, SGRQ-C, or SF 36 in both groups. CONCLUSION: In patients with COPD, inhaled triple therapy with budesonide-formoterol-tiotropium as compared to placebo-tiotropium improves pulmonary function while preserving sleep quality and architecture.

Utility of the ROX Index in Predicting Intubation for Patients With COVID-19-Related Hypoxemic Respiratory Failure Receiving High-Flow Nasal Therapy: Retrospective Cohort Study.

BACKGROUND: The use of high-flow nasal therapy (HFNT) to treat COVID-19 pneumonia has been greatly debated around the world due to concerns about increased health care worker transmission and delays in invasive mechanical ventilation (IMV). Herein, we analyzed the utility of the noninvasive ROX (ratio of oxygen saturation) index to predict the need for and timing of IMV. OBJECTIVE: This study aimed to assess whether the ROX index can be a useful score to predict intubation and IMV in patients receiving HFNT as treatment for COVID-19-related hypoxemic respiratory failure. METHODS: This is a retrospective cohort analysis of 129 consecutive patients with COVID-19 admitted to Temple University Hospital in Philadelphia, PA, from March 10, 2020, to May 17, 2020. This is a single-center study conducted in designated COVID-19 units (intensive care unit and other wards) at Temple University Hospital. Patients with moderate and severe hypoxemic respiratory failure treated with HFNT were included in the study. HFNT patients were divided into two groups: HFNT only and intubation (ie, patients who progressed from HFNT to IMV). The primary outcome was the value of the ROX index in predicting the need for IMV. Secondary outcomes were mortality, rate of intubation, length of stay, and rate of nosocomial infections in a cohort treated initially with HFNT. RESULTS: Of the 837 patients with COVID-19, 129 met the inclusion criteria. The mean age was 60.8 (SD 13.6) years, mean BMI was 32.6 (SD 8) kg/m², 58 (45%) were female, 72 (55.8%) were African American, 40 (31%) were Hispanic, and 48 (37.2%) were nonsmokers. The mean time to intubation was 2.5 (SD 3.3) days. An ROX index value of less than 5 at HFNT initiation was suggestive of progression to IMV (odds ratio [OR] 2.137, P=.052). Any further decrease in ROX index value after HFNT initiation was predictive of intubation (OR 14.67, P<.001). Mortality was 11.2% (n=10) in the HFNT-only group versus 47.5% (n=19) in the intubation group (P<.001). Mortality and need for pulmonary vasodilators were higher in the intubation group. CONCLUSIONS: The ROX index helps decide which patients need IMV and may limit eventual morbidity and mortality associated with the progression to IMV.

Pulmonary vasculopathy in explanted lungs from patients with interstitial lung disease undergoing lung transplantation.

BACKGROUND: Pulmonary hypertension (PH) causes increased morbidity and mortality in patients with interstitial lung diseases (ILD). Classification schemes, while well-characterised for the vasculopathy of idiopathic PH, have been applied, unchallenged, to ILD-related PH. We evaluated pulmonary arterial histopathology in explanted human lung tissue from patients who were transplanted for advanced fibrotic ILD. METHODS: Lung explants from 38 adult patients who underwent lung transplantation were included. Patients were divided into three groups: none, mild/moderate and severe PH by mean pulmonary artery pressure (mPAP) measured at pre lung transplantation right heart catheterisation (RHC). Grading of pulmonary vasculopathy according to Heath and Edwards scheme, and prelung transplantation evaluation data were compared between the groups. RESULTS: 38 patients with fibrotic ILDs were included, the majority (21) with idiopathic pulmonary fibrosis. Of the 38 patients, 18 had severe PH, 13 had mild/moderate PH and 7 had no PH by RHC. 16 of 38 patients had severe pulmonary arterial vasculopathy including vascular occlusion with intimal fibrosis and/or plexiform lesions. There were no correlations between mPAP and lung diffusion with the severity of pulmonary arterial pathological grade (Spearman's rho=0.14, p=0.34, rho=0.11, p=0.49, respectively). CONCLUSIONS: Patients with end stage ILD had severe pulmonary arterial vasculopathy in their explanted lungs irrespective of the presence and/or severity of PH as measured by RHC. These findings suggest that advanced pulmonary arterial vasculopathy is common in patients with advanced fibrotic ILD and may develop prior to the clinical detection of PH by RHC.

Treatment of sleep disordered breathing in congestive heart failure.

In patients with congestive heart failure, sleep disordered breathing occurs commonly and is associated with an increased mortality. In addition to central sleep apnea (Cheyne-Stokes respiration), obstructive sleep apnea is more prevalent in patients with congestive heart failure than in the general population. As a result, a number of treatments have been investigated, with varying results. While many therapies may improve the severity of sleep disordered breathing, only positive pressure ventilation has been shown to improve cardiac function. Newer forms of positive pressure ventilation, such as adaptive servo-ventilation, appear to be even more effective at correcting central sleep apnea. Whether any of these treatments have an effect on transplant-free survival is presently unknown and awaits further study.

Use of positional therapy when incorporated into a diagnosis-treatment algorithm for obstructive sleep apnea.

PURPOSE: Positional obstructive sleep apnea (OSA) is prevalent. We hypothesized that by incorporating positional therapy into a diagnosis-treatment algorithm for OSA it would frequently be prescribed as an appropriate first-line therapy. METHODS: Fifty-nine members (45 males, 49±9 yrs, BMI 35.2±5.6 kg/m2) of the Law Enforcement Health Benefits (LEHB), Inc. of Philadelphia with clinically suspected OSA were evaluated. Patients completed an Epworth Sleepiness Scale (ESS) questionnaire and a home sleep test (HST). Patients diagnosed with positional OSA (non-supine apnea-hypopnea index [AHI] < 5 events/hr) were offered positional therapy. A cost comparison to continuous positive airway pressure (CPAP) therapy was performed. RESULTS: Fifty-four (92%) of the patients (43 males, 49±9 yrs, BMI 35.2±5.3 kg/m2) had OSA on their HST (AHI 24.2±20.1 events/hr). Sixteen (30%) patients had positional OSA. Compared to non-positional patients, patients with positional OSA were less heavy (32.4±5.1 vs. 36.4±5.1 kg/m2, respectively [p=0.009]), less sleepy (ESS 8±5 vs. 12±5, respectively [p=0.009]), and had less severe OSA (AHI 10.4±4.3 vs. 30.0±21.3 events/hr, respectively [p<0.001]). Thirteen of the 16 patients with positional OSA agreed to positional therapy and 31 non-positional OSA patients agreed to CPAP therapy. Based on initial costs, incorporating positional therapy ($189.95/device compared to CPAP therapy at $962.49/device) into the treatment algorithm resulted in a 24% cost savings compared to if all the patients were initiated on CPAP therapy. CONCLUSION: With the high prevalence of positional OSA, using a diagnosis-treatment algorithm that incorporates positional therapy allows it to be more frequently considered as a cost effective first-line therapy for OSA.

Full face mask for noninvasive positive-pressure ventilation in patients with acute respiratory failure.

BACKGROUND: Noninvasive positive-pressure ventilation (NPPV) is commonly used to improve ventilation and oxygenation in patients with acute respiratory failure (ARF). Mask leak and intolerance due to facial discomfort or claustrophobia often occur with NPPV and are frequently cited reasons for treatment failure. METHODS: Retrospective review of patient records from a tertiary-care referral hospital. RESULTS: We report the effectiveness of a full face mask in the application of NPPV for 10 nonambulatory patients (mean [SD], 61 [9] years) who had a combined total of 13 episodes of ARF. After these patients were unable to receive NPPV therapy via the more commonly available nasal or oronasal masks, care was provided using full face masks. Eight of 10 patients had hypercapnic respiratory failure; 2 patients, hypoxemic respiratory failure. All patients were placed on ventilation initially using a bi-level positive airway pressure device. Subsequently, patient ventilation was achieved using a Puritan Bennett 7200a ventilator for on-line respiratory monitoring. The mean (SD) duration of treatment with NPPV was 9.7 (2.7) hours per day for 3.0 (1.6) days. Following NPPV via full face mask, the patients' Paco(2) decreased (65 [20] vs 82 [27] mm Hg, P=.09) and pH increased significantly (7.36 [0.07] vs 7.26 [0.07], P<.05) in less than 2 hours. Moreover, the patients demonstrated decreased respiratory rate (18 [7] vs 32 [8] breaths/min, P<.01), heart rate (106 [13] vs 124 [16] beats/min, P=.008), and Acute Physiology and Chronic Health Evaluation II scores (12 [3] vs 17 [4], P<.005) after NPPV via full face mask. These cardiorespiratory alterations occurred as early as 1 hour after NPPV initiation and were maintained throughout treatment. Two patients required endotracheal intubation because of copious purulent secretions. CONCLUSION: For individuals with hypercapnic respiratory failure who cannot tolerate NPPV using nasal or oronasal masks, use of full face masks may improve outcomes, allowing physicians to avoid ordering endotracheal intubation and mechanical ventilation.

Effect of Emphysema Severity on the Apnea-Hypopnea Index in Smokers with Obstructive Sleep Apnea.

RATIONALE: The presence of obstructive sleep apnea (OSA) in patients with chronic obstructive pulmonary disease (COPD) is referred to as the OSA-COPD overlap syndrome. While lung inflation has been shown to be an important factor in determining upper airway stability, its role in determining OSA severity in smokers, including those with emphysema, has not been evaluated. OBJECTIVES: To evaluate the importance of lung inflation on OSA severity (apnea-hypopnea index [AHI]) in smokers with suspected OSA. METHODS: Fifty-one smokers (18 males; mean [±SD] age, 59 ± 9 yr; body mass index [BMI], 32 ± 9 kg/m(2)) who were part of the Genetic Epidemiology of COPD (COPDGene) project were studied. Patients underwent a full-night polysomnography for suspected OSA. Other testing included spirometry and volumetric chest computed tomography (CT) for quantitative measurement of CT-derived percent emphysema and CT-derived percent gas trapping. MEASUREMENTS AND MAIN RESULTS: For the group overall, there was evidence of obstructive airway disease by spirometry (FEV1, 1.4 ± 0.5 L, 58 ± 14% predicted) and emphysema by quantitative CT (CT-derived percent emphysema, 11 ± 13%; CT-derived percent gas trapping, 31.6 ± 24.1%). Twenty-nine (57%) of the patients had OSA (AHI, 18 ± 12 events/h). Patients with OSA had a higher BMI but were younger than those without OSA (BMI, 35 ± 9 kg/m(2) vs. 29 ± 7 kg/m(2), respectively [P = 0.007]; age, 56 ± 8 yr vs. 62 ± 9 yr, respectively [P = 0.01]). There was an inverse correlation between the AHI and the CT-derived percent emphysema and CT-derived percent gas trapping, both for the entire group (r = -0.41 [P < 0.01] and r = -0.44 [P < 0.01], respectively) and when just those patients with OSA were evaluated (r = -0.43 [P = 0.04] and r = -0.49 [P = 0.03], respectively). Multiple linear regression revealed that, in addition to CT-derived percent emphysema and CT-derived percent gas trapping, sex and BMI were important in determining the AHI in these patients. CONCLUSIONS: In smokers with OSA, increased gas trapping and emphysema as assessed by CT are associated with a decreased AHI. Along with sex and BMI, these measurements may be important in determining the severity of OSA in patients with COPD and may offer a protective mechanism in patients with more advanced disease.

Patient-physician communication: why and how.

Patient-physician communication is an integral part of clinical practice. When done well, such communication produces a therapeutic effect for the patient, as has been validated in controlled studies. Formal training programs have been created to enhance and measure specific communication skills. Many of these efforts, however, focus on medical schools and early postgraduate years and, therefore, remain isolated in academic settings. Thus, the communication skills of the busy physician often remain poorly developed, and the need for established physicians to become better communicators continues. In this article, the authors briefly review the why and how of effective patient-physician communication. They begin by reviewing current data on the benefits of effective communication in the clinical context of physicians caring for patients. The authors then offer specific guidance on how to achieve effective communication in the patient-physician relationship.

Effects of nasal continuous positive airway pressure on oxygen body stores in patients with Cheyne-Stokes respiration and congestive heart failure.

STUDY OBJECTIVES: The mechanism(s) by which nasal continuous positive airway pressure (CPAP) is effective in the treatment of Cheyne-Stokes respiration (CSR) in patients with congestive heart failure (CHF) remains uncertain, and may involve an increase in total oxygen body stores (dampening), changes in central and peripheral controller gain, and/or improvement in cardiac function. The purpose of this study was to evaluate the effects of nasal CPAP on total oxygen stores, as measured by the rate of fall of arterial oxyhemoglobin saturation (dSaO(2)/dt), to determine if dampening may play a role in the attenuation of CSR in patients with CHF. DESIGN: Prospective controlled trial. SETTING: University hospital. PATIENTS: Nine male patients (mean +/- SD age, 59 +/- 8 years) with CHF and a mean left ventricular ejection fraction (LVEF) of 16 +/- 4%. INTERVENTIONS AND MEASUREMENTS: All patients had known CSR, as identified on a baseline polysomnographic study. Patients then underwent repeat polysomnography while receiving nasal CPAP (9 +/- 0.3 cm H(2)O). The polysomnography consisted of recording of breathing pattern, pulse oximetry, and EEG. dSaO(2)/dt was measured as the slope of a line drawn adjacent to the falling linear portion of the arterial oxygen saturation (SaO(2)) curve associated with a central apnea. All patients underwent echocardiography and right-heart catheterization within 1 month of the study to measure LVEF and cardiac hemodynamics, respectively. RESULTS: There was a significant decrease in the apnea-hypopnea index (AHI) with nasal CPAP, from 44 +/- 27 events per hour at baseline to 15 +/- 24 events per hour with nasal CPAP (p = 0.004). When compared to baseline, dSaO(2)/dt significantly decreased with nasal CPAP from 0.42 +/- 0.15% to 0.20 +/- 0.07%/s (p < 0.001). The postapneic SaO(2), when compared to baseline, significantly increased with nasal CPAP, from 87 +/- 5% to 91 +/- 4% (p < 0.05). The preapneic SaO(2) did not significantly change, from a baseline of 96 +/- 2% to 96 +/- 3% with nasal CPAP (p = 0.8). When compared to baseline, the apnea duration and heart rate did not change with nasal CPAP. While there was a significant correlation noted between baseline postapneic SaO(2) and dSaO(2)/dt (r = 0.8, p = 0.02), no correlation was seen between baseline preapneic SaO(2) and dSaO(2)/dt (r = 0.1, p = 0.7). A significant correlation was noted between baseline dSaO(2)/dt and the AHI (r = 0.7, p = 0.02). With CPAP, there was a significant correlation noted between dSaO(2)/dt and the AHI (R = 0.7, p = 0.04), but no correlation was noted between dSaO(2)/dt and postapneic SaO(2) (R = 0.1, p = 0.8). CONCLUSION: Nasal CPAP significantly decreases dSaO(2)/dt and thus increases total body oxygen stores in patients with CSR and CHF. By increasing oxygen body stores, dampening may be one of the mechanisms responsible for the attenuation of CSR seen with nasal CPAP.

Acute and Chronic Effects of Misoprostol in the Control of Asthma: A Pilot Study in Five Subjects.

Asthma is an inflammatory disease involving the airways. E-series prostaglandins have potent anti-inflammatory effects on neutrophils and T lymphocytes. Accordingly, we tested the acute (i.e., 6 h) and chronic (i.e., 1 week) effects of oral misoprostol 200 &mgr;g in five stable asthmatics. A double-blind, randomized, crossover design was used. Airway function was assessed from measurements of forced expiratory volume in 1 s (FEV(1)). The number of puffs of the inhaled beta-adrenergic agonist bronchodilator, albuterol, taken for symptomatic rescue, was assessed by diary. FEV(1) measured serially for 6 h after 200 &mgr;g misoprostol was similar on misoprostol and placebo days in all subjects. In contrast, three of the five subjects showed appreciable increases in FEV(1) during a week of misoprostol compared to either baseline or placebo week. Two subjects showed no change in the FEV(1) with 1 week of misoprostol. All three of the subjects who kept a diary decreased the number of puffs of albuterol during the misoprostol compared to placebo period. Of note, in these three subjects, airway function improved (n = 1) or remained the same (n = 2) despite a diminution in the number of puffs of a beta-agonist administered. None of the subjects administered the 200-&mgr;g oral dose QID reported any significant symptoms or adverse reaction. In conclusion, several inferences can be drawn from this early preliminary study. These data suggest that a trial involving a large number of subjects, a longer period of treatment, and a more objective method of assessing inhaler use may be useful in evaluating the chronic effects of misoprostol in asthma.

Scope and impact of allergic rhinitis.

Allergic rhinitis is estimated to affect as many as 40 million people in the United States on a regular basis, and even more individuals who have occasional symptoms. The disease is associated with a considerable burden on the healthcare system, accounting for a total of $7.9 billion in direct and indirect costs in 1997, and with significant adverse effects on patients' quality of life, including disturbed sleep and impaired function at work and school. The pathophysiology of allergic rhinitis is complex, involving inflammatory mediators and immune cells that produce allergy symptoms via multiple mechanisms. The first principle of clinical management of patients with allergic rhinitis is avoidance of exposure to allergens, but this measure can be very difficult, and most patients require pharmacotherapy. Allergy vaccine therapy may be an appropriate and necessary option in selected patients with allergies refractory to other treatment modalities.

Determinants of CPAP Adherence in Hispanics with Obstructive Sleep Apnea.

Purpose. We hypothesized that socioeconomic factors and a language barrier would impact adherence with continuous positive airway pressure (CPAP) among Hispanics with obstructive sleep apnea (OSA). Methods. Patients with OSA who were prescribed CPAP for at least 1 year and completed a questionnaire evaluating demographic data, socioeconomic status, and CPAP knowledge and adherence participated in the study. Results. Seventy-nine patients (26 males; 53 ± 11 yrs; body mass index (BMI) = 45 ± 9 kg/m(2)) with apnea-hypopnea index (AHI) 33 ± 30 events/hr completed the study. Included were 25 Hispanics, 39 African Americans, and 15 Caucasians, with no difference in age, AHI, CPAP use, or BMI between the groups. While there was a difference in educational level (P = 0.006), income level (P < 0.001), and employment status (P = 0.03) between the groups, these did not influence CPAP adherence. Instead, overall improvement in quality of life and health status and perceived benefit from CPAP influenced adherence, both for the group as a whole (P = 0.03, P = 0.004, and P = 0.001, resp.), as well as in Hispanics (P = 0.02, P = 0.02, P = 0.03, resp.). Conclusion. In Hispanic patients with OSA, perceived benefit with therapy, rather than socioeconomic status or a language barrier, appears to be the most important factor in determining CPAP adherence.

Comparison of positional therapy to CPAP in patients with positional obstructive sleep apnea.

STUDY OBJECTIVES: We hypothesized that positional therapy would be equivalent to continuous positive airway pressure (CPAP) at normalizing the apnea-hypopnea index (AHI) in patients with positional obstructive sleep apnea (OSA). METHODS: Thirty-eight patients (25 men, 49 +/- 12 years of age, body mass index 31 +/- 5 kg/m2) with positional OSA (nonsupine AHI <5 events/h) identified on a baseline polysomnogram were studied. Patients were randomly assigned to a night with a positional device (PD) and a night on CPAP (10 +/- 3 cm H2O). RESULTS: Positional therapy was equivalent to CPAP at normalizing the AHI to less than 5 events per hour (92% and 97%, respectively [p = 0.16]). The AHI decreased from a median of 11 events per hour (interquartile range 9-15, range 6-26) to 2 (1-4, 0-8) and 0 events per hour (0-2, 0-7) with the PD and CPAP, respectively; the difference between treatments was significant (p < 0.001). The percentage of total sleep time in the supine position decreased from 40% (23%-67%, 7%-82%) to 0% (0%-0%, 0%-27%) with the PD (p < 0.001) but was unchanged with CPAP (51% [36%-69%, 0%-100%]). The lowest SaO2 increased with the PD and CPAP therapy, from 85% (83%-89%, 76%-93%) to 89% (86%-9%1, 78%-95%) and 89% (87%-91%, 81%-95%), respectively (p < 0.001). The total sleep time was unchanged with the PD, but decreased with CPAP, from 338 (303-374, 159-449) minutes to 334 (287-366, 194-397) and 319 (266-343, 170-386) minutes, respectively (p = 0.02). Sleep efficiency, spontaneous arousal index, and sleep architecture were unchanged with both therapies. CONCLUSION: Positional therapy is equivalent to CPAP at normalizing the AHI in patients with positional OSA, with similar effects on sleep quality and nocturnal oxygenation.