The Role of Weight Management in the Treatment of Adult Obstructive Sleep Apnea. An Official American Thoracic Society Clinical Practice Guideline.

BACKGROUND: Overweight/obesity is a common, reversible risk factor for obstructive sleep apnea severity (OSA). The purpose of this guideline is to provide evidence-based recommendations for the management of overweight/obesity in patients with OSA. METHODS: The Grading of Recommendations, Assessment, Development and Evaluation approach was used to evaluate the literature. Clinical recommendations were formulated by a panel of pulmonary, sleep medicine, weight management, and behavioral science specialists. RESULTS: Behavioral, pharmacological, and surgical treatments promote weight loss and can reduce OSA severity, reverse common comorbidities, and improve quality of life, although published studies have methodological limitations. After considering the quality of evidence, feasibility, and acceptability of these interventions, the panel made a strong recommendation that patients with OSA who are overweight or obese be treated with comprehensive lifestyle intervention consisting of 1) a reduced-calorie diet, 2) exercise or increased physical activity, and 3) behavioral guidance. Conditional recommendations were made regarding reduced-calorie diet and exercise/increased physical activity as separate management tools. Pharmacological therapy and bariatric surgery are appropriate for selected patients who require further assistance with weight loss. CONCLUSIONS: Weight-loss interventions, especially comprehensive lifestyle interventions, are associated with improvements in OSA severity, cardiometabolic comorbidities, and quality of life. The American Thoracic Society recommends that clinicians regularly assess weight and incorporate weight management strategies that are tailored to individual patient preferences into the routine treatment of adult patients with OSA who are overweight or obese.

I-TRACH: Validating A Tool for Predicting Prolonged Mechanical Ventilation.

PURPOSE: We previously developed a bedside model (I-TRACH), which used commonly obtained data at the time of intubation to predict the duration of mechanical ventilation (MV). We now sought to validate this in a prospective trial. METHODS: A prospective, observational study of 225 consecutive adult medical intensive care unit patients requiring MV. Utilizing the original 6 variables used in the I-TRACH model (Intubation in the ICU, Tachycardia [heart rate > 110], Renal dysfunction [blood urea nitrogen > 25], Acidemia [pH < 7.25], Creatinine [>2.0 or >50% increase from baseline values], and decreased HCO3 [<20]), we (1) confirmed that these were still predictive of length of MV by multivariate analysis and (2) assessed the correlation between the number of criteria met and the subsequent duration of MV. In addition, we compared the performance of I-TRACH to Acute Physiology Age Chronic Health Evaluation-II and III, Sequential Organ Failure Assessment, and Acute Physiology Score as predictors of length of MV. RESULTS: Mean age was 62.6 ± 18.7 years, with a mean duration of MV of 5.8 ± 5.7 days. The number of I-TRACH criteria met directly correlated with the duration of MV. Individuals with ≥4 criteria were significantly more likely to require MV >7 and >14 days. Similarly, those who remained on ventilators for both >7 and >14 days met significantly more I-TRACH criteria than those requiring shorter durations of MV (1.7 ± 1.3 vs 2.8 ± 1.3 vs 3.8 ± 1.3 criteria, P < .001). I-TRACH performed better than all other models used to predict the duration of MV. CONCLUSION: Similar to our previous retrospective study, these findings validate I-TRACH in determining the subsequent need for MV >7 and >14 days at the time of intubation.

Differences in sleep habits, study time, and academic performance between US-born and foreign-born college students.

PURPOSE: To inform the design of a sleep improvement program for college students, we assessed academic performance, sleep habits, study hours, and extracurricular time, hypothesizing that there would be differences between US-born and foreign-born students. METHODS: Questionnaires queried participants on bedtimes, wake times, nap frequency, differences in weekday and weekend sleep habits, study hours, grade point average, time spent at paid employment, and other extracurricular activities. Comparisons were made using chi square tests for categorical data and t tests for continuous data between US-born and foreign-born students. RESULTS: Of 120 participants (55 % women) with racial diversity (49 whites, 18 blacks, 26 Hispanics, 14 Asians, and 13 other), 49 (41 %) were foreign-born. Comparisons between US-born and foreign-born students showed no differences in average age or gender though US-born had more whites. There were no differences between US-born and foreign-born students for grade point averages, weekday bedtimes, wake times, or total sleep times. However, US-born students averaged 50 min less study time per day (p = 0.01), had almost 9 h less paid employment per week (14.5 vs 23.4 h per week, p = 0.001), and stayed up to socialize more frequently (63 vs 43 %, p = 0.03). Foreign-born students awakened an hour earlier and averaged 40 min less sleep per night on weekends. CONCLUSIONS: Cultural differences among college students have a profound effect on sleep habits, study hours, and extracurricular time. The design of a sleep improvement program targeting a population with diverse cultural backgrounds must factor in such behavioral variations in order to have relevance and impact.

Sleep disorders in combat-related PTSD.

PURPOSE: We sought to assess the rate of sleep complaints and sleep disorders among active duty soldiers with deployment-related PTSD and to determine whether any clinical features differentiated those with sleep disorders. METHODS: Retrospective review of consecutive soldiers diagnosed with PTSD. We recorded subjective measures of sleep and polysomnographic data. We compared clinical and demographic variables including psychoactive medication use, psychiatric comorbidity, and combat-related traumatic injury with the presence of sleep disorders. RESULTS: One hundred thirty patients were included (91.5 % male, mean age of 35.1 ± 10.6 years, mean body mass index (BMI) 28.9 ± 4.4 Kg/m(2)). About 88.5 % had comorbid depression, with the majority (96.2 %) taking psychoactive medications (mean 3.4 ± 1.6 medications per patient). Over half of the cohort suffered combat-related traumatic physical injuries (54.6 %). The obstructive sleep apnea syndrome (OSAS) was diagnosed in 67.3 % (80 % of the cohort underwent polysomnography), with a mean apnea hypopnea index of 24.1 ± 22.8 events/hour and a mean oxygen saturation nadir of 84.2 ± 5.7 %. OSAS was significantly more common in the non-injured soldiers (72.9 vs. 38.0 %, p < 0.001). In multivariate analysis, absence of physical injury showed a trend towards predicting OSAS. CONCLUSIONS: Sleep complaints are common among soldiers with PTSD. We observed significantly higher rates of OSAS among those without physical injuries, raising the possibility that underlying sleep-disordered breathing is a risk factor for the development of PTSD. This potential association requires further validation.

The impact of sleep on soldier performance.

The military population is particularly vulnerable to a multitude of sleep-related disorders owing to the type of work performed by active duty servicemembers (ADSMs). Inadequate sleep, due to insufficient quantity or quality, is increasingly recognized as a public health concern. Traditionally, ADSMs have been encouraged that they can adapt to insufficient sleep just as the body adapts to physical training, but there is a substantial body of scientific literature which argues that this is not possible. Additionally, the military work environment creates unique challenges with respect to treatment options for common sleep disorders like obstructive sleep apnea, restless legs syndrome, and parasomnias. This review highlights sleep disorders which are prevalent in the modern military force and discusses the impact of poor sleep on overall performance. Medical treatments and recommendations for unit leaders are also discussed.

Correlation between positive airway pressure and medication adherence: the healthy user effect.

STUDY OBJECTIVES: Despite the efficacy of positive airway pressure (PAP) for the treatment of obstructive sleep apnea, adherence remains challenging and negatively affects assessments of effectiveness. It is unclear whether low adherence is due to intolerance of PAP or whether this reflects overall adherence with medical therapy. We sought to correlate PAP use with medication adherence to determine whether poor adherence with PAP was specific to this treatment or represented global compliance with medical therapy. METHODS: A total of 600 consecutive patients with obstructive sleep apnea were treated with PAP. Objective measures of PAP use were correlated with medication adherence. We included all chronically used medications, defined as medications used daily for at least 90 days prior to PAP initiation. Medication use was verified using an electronic health record. PAP adherence ("regular use") was defined as PAP use for ≥ 4 hours/night on ≥ 70% of nights. Medication adherence was defined as > 70% of pills taken as prescribed. RESULTS: Complete records were available for 566 patients; 361 (63.8%) used chronic medications. The cohort was primarily men (90.3%, age 44.6 ± 10.2 years) with moderate obstructive sleep apnea (apnea-hypopnea index, 18.1 ± 13.9 events/h). In patients on chronic medications, PAP was used 55.8% of nights and 37.7% were regular users. Patients who were adherent with medications used PAP more hours/night (5.4 vs 4.6, P < .001) and were more likely to have regular PAP use compared with those nonadherent with medications (P = .04). CONCLUSIONS: Adherence with PAP correlated with adherence to chronic medications. Low PAP adherence may reflect an individual's global adherence to medical care. This association may lead to better identification of patients who benefit from targeted therapy to improve overall health care adherence. CITATION: Lettieri MJ, Warren WA, Walter RJ, Lettieri CJ. Correlation between positive airway pressure and medication adherence: the healthy user effect. J Clin Sleep Med. 2024;20(7):1087-1092.

Early to bed, early to rise! Sleep habits and academic performance in college students.

PURPOSE: Prior studies have placed emphasis on the need for adequate total sleep time for student performance. We sought to investigate the relative importance of total sleep time compared to the timing of sleep and wakefulness for academic performance. METHODS: We performed a questionnaire-based survey of college students in October 2007. The questionnaire gathered detailed information on sleep habits including naps, reasons for missing sleep, academic performance, study habits, time spent working outside of school, and stimulant use. RESULTS: Compared to those with the lowest academic performance, students with the highest performance had significantly earlier bedtimes (p = 0.05) and wake times (p = 0.008). Napping tended to be more common among high performers (p = 0.07). Of importance, there were no significant differences in total sleep time with or without naps, weekend sleep habits, study time, gender, race, reasons for staying up at night, nor in use of caffeinated beverages, over-the-counter stimulant pills, or use of prescription stimulants. CONCLUSIONS: Timing of sleep and wakefulness correlated more closely with academic performance than total sleep time and other relevant factors. These findings have important implications for programs intended to improve academic performance by targeting sleep habits of students.

Effects of a short course of eszopiclone on continuous positive airway pressure adherence: a randomized trial.

BACKGROUND: Adherence to short-term continuous positive airway pressure (CPAP) may predict long-term use. Unfortunately, initial CPAP intolerance may lead to poor adherence or abandonment of therapy. OBJECTIVE: To determine whether a short course of eszopiclone at the onset of therapy improves long-term CPAP adherence more than placebo in adults with obstructive sleep apnea. DESIGN: Parallel randomized, placebo-controlled trial from March 2007 to December 2008. Randomization, maintained and concealed centrally by pharmacy personnel, was computer-generated using fixed blocks of 10. Referring physicians, investigators, and patients were blinded to the treatment assignment until after the final data were collected. (ClinicalTrials.gov registration number: NCT00612157). SETTING: Academic sleep disorder center. PATIENTS: 160 adults (mean age, 45.7 years [SD, 7.3]; mean apnea-hypopnea index, 36.9 events/h [SD, 23]) with newly diagnosed obstructive sleep apnea initiating CPAP. INTERVENTION: Eszopiclone, 3 mg (n = 76), or matching placebo (n = 78) for the first 14 nights of CPAP. MEASUREMENTS: Use of CPAP was measured weekly for 24 weeks. Adherence to CPAP (primary outcome) and the rate of CPAP discontinuation and improvements in symptoms (secondary outcomes) were compared. Follow-up at 1, 3, and 6 months was completed by 150, 136, and 120 patients, respectively. RESULTS: Patients in the eszopiclone group used CPAP for 20.8% more nights (95% CI, 7.2% to 34.4%; P = 0.003), 1.3 more hours per night for all nights (CI, 0.4 to 2.2 hours; P = 0.005), and 1.1 more hours per night of CPAP use (CI, 0.2 to 2.1 hours; P = 0.019). The hazard ratio for discontinuation of CPAP was 1.90 (CI, 1.1 to 3.4; P = 0.033) times higher in the placebo group. Side effects were reported in 7.1% of patients and did not differ between groups. LIMITATIONS: Patients had severe obstructive sleep apnea treated at a specialized sleep center with frequent follow-up; results may not be generalizable to different settings. Patients' tolerance to CPAP and their reasons for discontinuation were not assessed. CONCLUSION: Compared with placebo, a short course of eszopiclone during the first 2 weeks of CPAP improved adherence and led to fewer patients discontinuing therapy.

Treatment of Obstructive Sleep Apnea: Achieving Adherence to Positive Airway Pressure Treatment and Dealing with Complications.

Obstructive sleep apnea is a common and treatable condition, but therapeutic adherence is limited by numerous factors. Despite advances in positive airway pressure (PAP) technology and a multitude of effective pharmacologic and behavioral therapeutic interventions to overcome the most common barriers to PAP, adherence has not increased significantly over the past 30 years. This review aims to identify the most important factors that impact adherence, common barriers to treatment, and evidence-based treatment strategies to maximize the effectiveness of PAP treatment. Complications of PAP treatment and mitigation techniques are also discussed.

An intensivist-directed intensive care unit improves clinical outcomes in a combat zone.

OBJECTIVE: Intensivist-directed intensive care units (ICUs) have been shown to improve clinical outcomes. Numerous barriers exist that limit hospitals adopting this practice. We sought to show this staffing model can be implemented in an austere environment with limited resources resulting in improved outcomes. DESIGN: We conducted a retrospective observational cohort study of consecutive adult patients admitted to the ICU between March 2004 and January 2007. SETTING: This study was conducted in an ICU in a U.S. Army Combat Support Hospital deployed to Afghanistan. PATIENTS: North Atlantic Trade Organization members (U.S. military service members, American civilian contractors, members of the North Atlantic Trade Organization Coalition International Security Assistance Force), members of the Afghanistan National Army and National Police, and local Afghani nationals were included in the study. Both traumatic injuries and medical illnesses were treated. INTERVENTIONS: During the observation period, the ICU was converted from an open model to an intensivist-directed model. MEASUREMENTS AND MAIN RESULTS: Outcomes compared between the two models included ICU and hospital mortality, duration of mechanical ventilation, and ventilator-associated pneumonia rates. During the observation period, there were 2740 admissions, 965 of which were initially admitted to the ICU. We found significant reductions in ICU mortality (6.6% vs. 4.0%, p < 0.001), duration of mechanical ventilation (4.7 +/- 3.9 days vs. 3.1 +/- 2.7 days, p < 0.001), and rates of ventilator-associated pneumonia (42.5% vs. 8.0%; p < 0.001). CONCLUSIONS: Transition to an intensivist-directed ICU in an Army Combat Support Hospital improved outcomes among ICU patients. This study demonstrates the feasibility of using this model in an austere, combat environment.

Utility of split-night polysomnography in the diagnosis of upper airway resistance syndrome.

PURPOSE: Split-night polysomnography can both establish the diagnosis and titrate continuous positive airway pressure (CPAP) during a single study in patients with sleep-disordered breathing. We sought to determine if split-night polysomnography could be effectively used in upper airway resistance syndrome (UARS) without diminishing diagnostic accuracy or success of CPAP titration. METHODS: Consecutive patients diagnosed with UARS were included. Split-night studies were performed in patients meeting predefined criteria. We compared data between those undergoing traditional and split-night polysomnography. RESULTS: We included 100 consecutive patients (41.2 +/- 7.4 years, 54% men). Forty-six underwent split-night polysomnography. Groups were similar at baseline. There were no differences in polysomnography or success rate of CPAP titration. Among those not undergoing split-night studies, the mean time between diagnostic polysomnography and CPAP titration was 71.9 +/- 49.0 days. CONCLUSIONS: Split-night polysomnography can be effectively utilized to diagnose UARS and initiate CPAP therapy. This practice can reduce the number of studies needed and obviate the inherent delay in initiating CPAP therapy.

Eszopiclone improves overnight polysomnography and continuous positive airway pressure titration: a prospective, randomized, placebo-controlled trial.

STUDY OBJECTIVES: To assess whether premedication with eszopiclone would improve sleep duration and continuity during polysomnography, thereby improving the quality of diagnostic and CPAP titration studies. DESIGN: Prospective, double-blinded, placebo-controlled trial SETTING: Academic, multidisciplinary sleep center. PATIENTS: 226 adult subjects undergoing polysomnography for suspected sleep disordered breathing; 113 received eszopiclone and 113 received placebo. INTERVENTIONS: Subjects received eszopiclone 3 mg or matching placebo before polysomnography. We compared sleep latency, efficiency, total sleep time, and apnea-hypopnea index between these groups. We also compared rates of inadequate studies, defined as insufficient sleep time (< 120 min or sleep efficiency < or = 70%) or incomplete CPAP titrations (> or = 5 events/h on the highest CPAP or complete intolerance). MEASUREMENTS AND RESULTS: Eszopiclone premedication significantly improved a number of measured variables. Eszopiclone reduced sleep latency (21.7 +/- 27.1 vs. 32.6 +/- 38.2 min, P = 0.014), improved sleep efficiency (87.6% +/- 10.8% vs. 78.1% +/- 15.6%, P < 0.001), reduced wake after sleep onset (39.2 +/- 31.9 vs. 64.5 +/- 45.4 min, P <0.001) and prolonged sleep time (346.5 +/- 53.1 vs. 312.2 +/- 64.2 min, P < 0.001). Sleep efficiencies < or = 70% were more common with placebo than medication (21.2% vs. 7.1%, P = 0.004). Eszopiclone facilitated improved CPAP titrations with fewer residual events (5.7 +/- 10.3 vs. 11.9 +/- 19.6, P = 0.02) and fewer incomplete titrations (31.1% vs. 48.0%, P = 0.04). Poor quality studies (46.0% vs. 26.5%, P = 0.004) were more common with placebo than with eszopiclone. There was a trend for more non-usable studies with placebo (7.1% vs. 2.7%, P = 0.22). Side effects were uncommon and did not differ between groups. CONCLUSION: Pretreatment with eszopiclone improves the quality of polysomnography and CPAP titration and decreases the need to repeat studies. Given the ever-growing demand for polysomnography and the need to improve efficiency, the routine use of nonbenzodiazepines as premedication for polysomnography should be considered.

Ambulatory Surgery Has Minimal Impact on Sleep Parameters: A Prospective Observational Trial.

STUDY OBJECTIVES: The presence of obstructive sleep apnea (OSA) in ambulatory surgical patients causes significant perioperative concern; however, few data exist to guide clinicians' management decisions. The objective of this study was to measure changes in perioperative sleep parameters among an ambulatory surgery population. METHODS: This study is a prospective, observational study of ambulatory patients undergoing orthopedic surgery on an extremity. Study subjects completed three unattended home sleep apnea tests: baseline before surgery, the first night after surgery (N1), and third night after surgery (N3). Anesthesia and surgical teams were blinded to study participation and patients received routine perioperative care. RESULTS: Two hundred three subjects were enrolled and 166 completed the baseline home sleep test. Sixty-six (40.0%) had OSA at baseline, 35 patients received a new diagnosis, and 31 patients had a previous diagnosis of OSA. Of those with a previous diagnosis, 20 (64.5%) were compliant with continuous positive airway pressure therapy. Respiratory event index and SpO2 nadir did not significantly change postoperatively from baseline. Cumulative percentage of time oxygen saturation < 90% significantly increased N1 as compared to baseline for all patients except for those with moderate to severe OSA. CONCLUSIONS: Ambulatory surgery had minimal effect on sleep parameters and there was no increase in adverse events among patients with either treated or untreated OSA. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Title: Evaluation of Sleep Disordered Breathing Following Ambulatory Surgery; Identifier: NCT01851798; URL: https://clinicaltrials.gov/ct2/show/study/NCT01851798.

Sleep, Sleep Disorders, and Circadian Health following Mild Traumatic Brain Injury in Adults: Review and Research Agenda.

A rapidly expanding scientific literature supports the frequent co-occurrence of sleep and circadian disturbances following mild traumatic brain injury (mTBI). Although many questions remain unanswered, the preponderance of evidence suggests that sleep and circadian disorders can result from mTBI. Among those with mTBI, sleep disturbances and clinical sleep and circadian disorders contribute to the morbidity and long-term sequelae across domains of functional outcomes and quality of life. Specifically, along with deterioration of neurocognitive performance, insufficient and disturbed sleep can precede, exacerbate, or perpetuate many of the other common sequelae of mTBI, including depression, post-traumatic stress disorder, and chronic pain. Further, sleep and mTBI share neurophysiologic and neuroanatomic mechanisms that likely bear directly on success of rehabilitation following mTBI. For these reasons, focus on disturbed sleep as a modifiable treatment target has high likelihood of improving outcomes in mTBI. Here, we review relevant literature and present a research agenda to 1) advance understanding of the reciprocal relationships between sleep and circadian factors and mTBI sequelae and 2) advance rapidly the development of sleep-related treatments in this population.

Sequential compression devices for treatment of restless legs syndrome.

Restless legs syndrome (RLS) is a common disorder that presents with irresistible urges to move the legs and motor restlessness, worsening in the evening. RLS commonly causes insomnia and associated daytime symptoms. Treatment of first choice for RLS is usually medication, but medications are often ineffective or poorly tolerated. An effective nonpharmacologic therapy would be highly desirable. Here we review RLS and its treatment and present data from a pilot study on the effect of a novel treatment for this condition. The objective of this study was to determine the therapeutic effect of pneumatic sequential compression devices (SCDs) on RLS symptoms. We performed an uncontrolled, prospective interventional study using SCDs on a convenience sample of adults reliably diagnosed with RLS. Patients were asked to wear the SCD for an hour each evening before the usual time of onset of restless legs symptoms. Before and after 1-3 months of SCD therapy, patients completed validated questionnaires to assess RLS severity, daytime sleepiness, and impact of RLS on quality of life in the domains of social function, daily task function, sleep quality, and emotional well-being. Compliance with SCD therapy was measured using patient-recorded logs. Of 10 patients (7 women; age range, 37-80 yr; mean age, 56 yr), symptomatic for a mean of 68 months (range, 12-360 mo), 1 could not tolerate wearing the SCD and withdrew from the protocol after 3 days. The remaining 9 patients complied with therapy 58%-100% of nights (mean, 82%). Three patients experienced complete resolution of RLS and 6 patients had improvement of symptoms. Group severity score improved from 24/40 to 8/40 (p = 0.001). Epworth Sleepiness Scale score improved from 12/24 to 8/24 (p = 0.05). Every quality of life score improved: social function from 74% to 96% (p = 0.04), daily task function 63% to 80% (p = 0.05), sleep quality 27% to 63% (p = 0.003), and emotional well-being from 49% to 83% (p = 0.02). In this group of patients, wearing the SCD in the evening for an hour improved symptoms of RLS and improved quality of life, with complete resolution of symptoms in 3 of 10 patients.

Impact of diagnosing and treating obstructive sleep apnea on healthcare utilization.

PURPOSE: Obstructive sleep apnea (OSA) contributes to an increased risk for multiple co-morbidities and decreased quality of life. As a result, OSA patients may have higher usage of healthcare resources which can be mitigated with effective treatment. This study evaluates changes in healthcare utilization (HCU) following the initiation of therapy for OSA. METHODS: We conducted a retrospective study of newly diagnosed OSA patients. To assess total HCU, we incorporated the sum total of outpatient clinic encounters, laboratory tests, and medication prescriptions into a composite HCU score. Healthcare utilization for twelve months prior to positive airway pressure (PAP) was compared with twelve months after initiation of therapy. Reductions in HCU were correlated with PAP adherence. RESULTS: 650 consecutive patients were included. Mean age, gender, BMI, AHI, and ESS were 47.2 ± 8.8 years, 77.2% (men), 30.7 ± 4.9 kg/m2, 37.1 ± 30.3, and 13.1 ± 5.1, respectively. Prior to PAP, mean outpatient visits, laboratory studies, medication prescriptions, and HCU composite score were 11.6 ± 10.4, 13.7 ± 11.0, 4.7 ± 3.2, and 29.7 ± 18.6, respectively. Following initiation of treatment, a 32.8% reduction in non-sleep outpatient visits was identified (p = 0.01) and a 16.4% decrease in laboratory studies (p = 0.02) was observed. There was a 19.9% reduction (p = 0.002) in HCU composite score. Those who were adherent with PAP had a 25.7% reduction in HCU composite score versus a 4.9% increase in those who discontinued PAP therapy (p < 0.001). CONCLUSIONS: Diagnosing OSA and initiating PAP therapy resulted in a significant decrease in healthcare resource utilization. This reduction was greatest among those with higher baseline healthcare usage and those most adherent with therapy.

Treatment of Obstructive Sleep Apnea: Achieving Adherence to Positive Airway Pressure Treatment and Dealing with Complications.

Obstructive sleep apnea is a common and treatable condition, but therapeutic adherence is limited by numerous factors. Despite advances in positive airway pressure (PAP) technology and a multitude of effective pharmacologic and behavioral therapeutic interventions to overcome the most common barriers to PAP, adherence has not increased significantly over the past 30 years. This review aims to identify the most important factors that impact adherence, common barriers to treatment, and evidence-based treatment strategies to maximize the effectiveness of PAP treatment. Complications of PAP treatment and mitigation techniques are also discussed.

Prevalence and outcomes of pulmonary arterial hypertension in advanced idiopathic pulmonary fibrosis.

STUDY OBJECTIVES: The development of pulmonary arterial hypertension (PAH) can complicate many interstitial lung diseases, including idiopathic pulmonary fibrosis (IPF). We sought to characterize the prevalence of PAH and its impact on survival in patients with advanced IPF. DESIGN: Retrospective analysis of consecutive IPF patients undergoing pretransplantation right heart catheterization. SETTING: Lung transplant and IPF referral center. METHODS: PAH was defined as a mean pulmonary artery pressure (mPAP) of > 25 mm Hg. We compared demographic, spirometric, 6-min walk test (6MWT) results, and survival outcomes between those with PAH and those without PAH. MEASUREMENTS AND RESULTS: Seventy-nine patients were included in the study. PAH was present in 31.6% of patients (mean [+/- SD] mPAP, 29.5 +/- 3.3 vs 19.1 +/- 3.7 mm Hg, respectively). Those patients with PAH had a lower mean diffusing capacity of the lung for carbon monoxide (Dlco) (37.6 +/- 11.3% vs 31.1 +/- 10.1%, respectively; p = 0.04) and were more likely to require supplemental oxygen (66.7% vs 17.6%, respectively; p < 0.0001). Mean distance walked (143.5 +/- 65.5 vs 365.9 +/- 81.8 m, respectively; p < 0.001) and mean pulse oximetric saturation nadir (80.1 +/- 3.7% vs 88.0 +/- 3.5%, respectively; p < 0.001) during the 6MWT were also lower among those with PAH. PAH was associated with a greater risk of death during the study period (mortality rate, 60.0% vs 29.9%, respectively; odds ratio, 2.6; 95% confidence interval [CI], 2.3 to 3.1; p = 0.001). One-year mortality rates were higher in those with PAH (28.0% vs 5.5%, respectively; p = 0.002). As a predictor of mortality, PAH had a sensitivity, specificity, and accuracy of 57.1%, 79.3%, and 73.4%, respectively. There was a linear correlation between mPAP and outcomes with higher pressures associated with a greater risk of mortality (hazard ratio, 1.09; 95% CI, 1.02 to 1.16). FVC and Dlco did not predict outcomes. CONCLUSIONS: PAH is common in advanced cases of IPF and significantly impacts survival. A reduced Dlco, supplemental oxygen requirement, or poor 6-min walk performance should raise suspicion of the presence of underlying PAH. Identifying PAH might be an important adjunct in monitoring disease progression, triaging for transplantation, and guiding therapy.

The distance-saturation product predicts mortality in idiopathic pulmonary fibrosis.

INTRODUCTION: The 6-min walk test (6MWT) has prognostic value in various pulmonary disorders including idiopathic pulmonary fibrosis (IPF). We determined the individual prognostic accuracy of distance walked and oxygen saturation during the 6MWT in patients with IPF. We defined a new composite index, the distance-saturation product (DSP), which is the product of distance walked and lowest oxygen saturation during the 6-min walk test. We compared the performance of the DSP to the individual 6MWT parameters in predicting mortality. METHODS: We evaluated pulmonary function tests, 6-min walk parameters and the DSP between survivors and non-survivors. The ability of each measure to discriminate outcomes was determined by receiver operator curves. RESULTS: 81 patients (48 survivors, 33 non-survivors) were included. Pulmonary function tests were similar and did not correlate with survival. Desaturation was greater (89.4% versus 83.7%, P<0.001) and distance walked was lower (406.9 versus 181.3m, P = 0.005) in non-survivors. The DSP was significantly lower among non-survivors (364.8 versus 153.5m%, P < 0.001) and predicted mortality more accurately than either individual 6MWT component (P = 0.035 versus desaturation, P=0.040 versus distance). A DSP <200 m% was associated with a seven-fold greater risk of 12-month mortality and an 18.0% shorter median survival compared with a DSP > 200 m% (P < 0.001). DISCUSSION: Each component of the 6-min walk independently predicted mortality in IPF with greater accuracy than spirometry. However, a composite of both parameters, the DSP, provides slightly greater accuracy and represents a novel measure for assessing survival in patients with IPF.