Steven Scharf

Study Objectives To examine rates of adherence to continuous positive airway pressure (CPAP) therapy among a representative sample of older adult Medicare beneficiaries with obstructive sleep apnea (OSA), and to identify demographic and health-related factors associated with CPAP adherence. Methods Using a 5% sample of Medicare claims data, we utilized Medicare policy and CPAP machine charges as a proxy for CPAP adherence. A cumulative logit model was used to identify demographic, medical, and psychiatric predictors of CPAP adherence status. Results Of beneficiaries who initiated CPAP (n = 3,229), 74.9% (n = 2,417) met the so-called “90-day Medicare adherence criteria,” but only 58.8% of these individuals (n = 1,420) continued to use CPAP throughout the entire 13-month rent-to-own period. Anxiety, anemia, fibromyalgia, traumatic brain injury, and lower socioeconomic status (SES) were all associated with reduced CPAP adherence. Conclusions These results provide the first national est...

BackgroundCOPD patients account for a large proportion of lung transplants; lung transplantation survival benefit for COPD patients is not well established.MethodsWe identified 4521 COPD patients in the United Network for Organ Sharing (UNOS) dataset transplanted from May 2005 to August 2016, and 604 patients assigned to receive pulmonary rehabilitation and medical management in the National Emphysema Treatment Trial (NETT). After trimming the populations for NETT eligibility criteria and data completeness, 1337 UNOS and 596 NETT patients remained. Kaplan–Meier estimates of transplant-free survival from transplantation for UNOS, and NETT randomisation, were compared between propensity score-matched UNOS (n=401) and NETT (n=262) patients.ResultsIn propensity-matched analyses, transplanted patients had better survival compared to medically managed patients in NETT (p=0.003). Stratifying on 6 min walk distance (6 MWD) and FEV1, UNOS patients with 6 MWD <1000 ft (∼300 m) or FEV1 <...

Introduction Central sleep apnea syndrome (CSA) is commonly found in patients with congestive heart failure, brainstem disorders, and narcotic use. Various treatment modalities have been used with varied effectiveness in reducing the apnea-hypopnea index (AHI) and improving ventilation in patients with CSA. This study assessed whether Volume Assured Pressure Support (VAPS), a BiLevel mode of ventilation, is effective in treating CSA. Methods We performed a retrospective review of polysomnography (PSG) and VAPS titration studies on 11 patients at our institution: 7 patients had CSA with Cheyne-Stokes Respiration, 2 patients had CSA attributed to narcotic use, and 2 patients had primary CSA. CSA was diagnosed if more than 50% of the disordered breathing events were central. Five patients had failed a Continuous Positive Airway Pressure (CPAP) titration and then proceeded to VAPS while in 6 patients, VAPS was the initial treatment modality tried. We examined the effectiveness of VAPS i...

Introduction Despite consensus recommendations regarding need for caution and careful management, sedative hypnotic insomnia therapies remain commonly prescribed among older adults. Further, sleep medications are often prescribed in the absence of a thorough sleep history or evaluation. However, little is known about delivery of sleep-related care following prescription of insomnia medications. Thus, the purpose of this study was to characterize the course of sleep-related care following a prescription fill for insomnia medication among older adults. Methods Our data source was a random 5% sample of Medicare administrative claims data from 2006-2013. Insomnia medications were identified by searching the Part D prescription drug claims and included FDA-approved insomnia-related medication classes and drugs. Sleep disorders were operationalized using International Classification of Diseases, Ninth Revision, Clinical Modification codes. Descriptive analyses were performed to estimate t...

Introduction Although several studies have evaluated the impact of board-certification in sleep medicine regarding obstructive sleep apnea treatment outcomes, no studies to date have identified predictive factors to determine which patients are evaluated by board-certified sleep medicine providers (BCSMP) in the clinical practice. Thus, the purpose of this study was to identify predictors of being seen by a BCSMP, relative to non-sleep specialist providers. Methods Our data source was a random 5% sample of Medicare administrative claims data from 2006-2013. Sleep disorder diagnoses such as insomnia, obstructive sleep apnea, restless legs syndrome, hypersomnias, and parasomnias, as well as medical comorbidities including cardiovascular, cerebrovascular, mood, pulmonary, and neurological disorders, were operationalized using International Classification of Diseases, Ninth Revision, Clinical Modification codes. Demographic data were obtained from the claims. BCSMP were identified using...

Introduction Obstructive sleep apnea (OSA) is a common disease, often treated using continuous positive airway pressure (CPAP). In many cases, patients fail an attended CPAP titration study, often due to inadequate control of AHI, and treatment-emergent central apneas as CPAP is increased. Here, we report our experience using volume-assured pressure support (VAPS) for these patients. Methods We retrospectively reviewed records of 45 adults who had OSA diagnosed on polysomnography (PSG) in whom CPAP titration had failed. In these patients, VAPS-AE (adjustable expiratory pressure) titrations were performed. Patients with central sleep apnea on baseline PSG were excluded. Results Reasons for CPAP titration failure included: treatment emergent central apneas (25), failure of maximum CPAP pressure to treat OSA (18), and persistent hypoxia (2). Average age was 57.9±13.1, BMI was 40.2±8.7, 26 males, Epworth sleepiness score was 10.7±7.9. The following significant changes from baseline PSG ...

Introduction Despite a growing literature regarding the impact of board-certification in sleep medicine, little is known about the complexity of patients seen by board-certified sleep medicine physicians (BCSMPs) relative to non-specialists. To address this gap, the purpose of the current study was to evaluate the differences in sleep complaints among Medicare beneficiaries seen by BCSMPs relative to individuals seen by non-specialists. Methods Our data source was a random 5% sample of Medicare administrative claims data from 2006-2013. Sleep disorders were operationalized using International Classification of Diseases, Ninth Revision, Clinical Modification codes. Descriptive analyses were performed to estimate the number of sleep disorder diagnoses patients received by provider status. BCSMPs were identified using a cross-matching procedure based on National Provider Identifier (NPI). Results A total of 57,209 Medicare beneficiaries received a sleep disorder diagnosis between 2006-...

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...

Due to their relatively homogeneous lifestyle and living environment, the Amish offer a novel opportunity to study the health associations of tobacco smoke exposure, particularly secondhand smoke. We hypothesized that secondhand smoke exposure is associated with worse pulmonary and cardiometabolic health. We examined cross-sectional data on 3568 Amish study participants, including tobacco use and secondhand smoke exposure from family members included in the study. Thirty-four percent of Amish men reported ever smoking. Of this proportion, 64% used cigars, 46% cigarettes, and 21% pipes. Less than 1% of women reported ever smoking. Smoking was associated with lower spirometric lung function, higher body mass index, lower HDL cholesterol, higher heart rate, lower ankle-brachial index, and larger aortic diameter in men. A greater number of sources of secondhand smoke exposure (defined from the total of spouses, parents, and siblings who smoke) was associated with higher body mass index ...

In paralyzed anesthetized dogs the cardiovascular effects of increasing positive end-expiratory pressure (PEEP) were explored under two conditions: a) end-expiratory lung volume increasing, b) end-expiratory lung volume kept nearly constant by matching pleural pressure rise to end-expiratory airway pressure rise. Two series of experiments were done: I) xenous return was allowed to fall, II) venous return was kept constant by infusion of volume. Right atrial pressure, pulmonary arterial pressure, and left atrial pressure increased under all conditions when measured relative to atmospheric pressure, but increased relative to pleural pressure only under condition a. The rise in left atrial relative to pleural pressure may indicate a degree of left ventricular dysfunction associated with increasing end-expiratory lung volume. Furthermore, when end-expiratory lung volume increased, inequality of the rise in pulmonary artery wedge pressure exceeded the rise in left atrial pressure in seri...

The BMI, obstruction, dyspnea, and exercise capacity (BODE) score is used to inform prognostic considerations for lung transplantation for COPD, but it has not been validated in this context. A large proportion of mortality in COPD is attributable to comorbidities that could preclude transplant candidacy. We hypothesized that patients with COPD who are selected as transplant candidates experience better survival than traditional interpretation of BODE scores might indicate. We performed a retrospective analysis of survival according to the BODE score for patients with COPD in the United Network of Organ Sharing (UNOS) database of lung transplantation candidates (n = 4,377) compared with the cohort of patients with COPD in which the BODE score was validated (n = 625). Median survival in the fourth quartile of BODE score was 59 months (95% CI, 51-77 months) in the UNOS cohort and 37 months (95% CI, 29-42 months) in the BODE validation cohort. In models controlling for BODE score and i...

It is not readily apparent how pulmonary function could be improved by resecting portions of the lung in patients with emphysema. In emphysema, elevation in residual volume relative to total lung capacity reduces forced expiratory volumes, increases inspiratory effort, and impairs inspiratory muscle mechanics. Lung volume reduction surgery (LVRS) better matches the size of the lungs to the size of the thorax containing them. This restores forced expiratory volumes and the mechanical advantage of the inspiratory muscles. In patients with heterogeneous emphysema, LVRS may also allow space occupied by cysts to be reclaimed by more normal lung. Newer, bronchoscopic methods for lung volume reduction seek to achieve similar ends by causing localized atelectasis, but may be hindered by the low collateral resistance of emphysematous lung. Understanding of the mechanisms of improved function after LVRS can help select patients more likely to benefit from this approach.

It is clear that being underweight is a poor prognostic sign in chronic obstructive pulmonary disease (COPD). It is also clear that undernutrition is at least in part associated with the severity of airflow obstruction. While both weight and body mass index are useful screening tools in the initial nutritional evaluation, fat-free mass (FFM) may be a better marker of undernutrition in patients with COPD. The causes of cachexia in patients with COPD are multifactorial and include decreased oral intake, the effect of increased work of breathing due to abnormal respiratory mechanics, and the effect of chronic systemic inflammation. Active nutritional supplementation in undernourished patients with COPD can lead to weight gain and improvements in respiratory muscle function and exercise performance. However, long-term effects of nutritional supplementation are not clear. In addition, the optimal type of nutritional supplementation needs to be explored further. The role of novel forms of...

Leukotrienes have been implicated in the pathogenesis of acute exacerbations of COPD, but leukotriene modifiers have not been studied as a possible therapy for exacerbations. We sought to test the safety and efficacy of adding oral zileuton (a 5-lipoxygenase inhibitor) to usual treatment for acute exacerbations of COPD requiring hospitalization. Randomized double-blind, placebo-controlled, parallel group study of zileuton 600 mg orally, 4 times daily versus placebo for 14 days starting within 12 hours of hospital admission for COPD exacerbation. Primary outcome measure was hospital length of stay; secondary outcomes included treatment failure and biomarkers of leukotriene production. Sixty subjects were randomized to zileuton and 59 to placebo (the study was stopped short of enrollment goals because of slow recruitment). There was no difference in hospital length of stay (3.75 +/- 2.19 vs. 3.86 +/- 3.06 days for zileuton vs. placebo, p = 0.39) or treatment failure (23% vs. 27% for z...

Background The major marker utilized to monitor COPD patients is forced expiratory volume in one second (FEV1). However, asingle measurement of FEV1 cannot reliably predict subsequent decline. Recent studies indicate that T lymphocytes and eosinophils are important determinants of disease stability in COPD. We therefore measured cytokine levels in the lung lavage fluid and plasma of COPD patients in order to determine if the levels of T cell or eosinophil related cytokines were predictive of the future course of the disease. Methods Baseline lung lavage and plasma samples were collected from COPD subjects with moderately severe airway obstruction and emphysematous changes on chest CT. The study participants were former smokers who had not had a disease exacerbation within the past six months or used steroids within the past two months. Those subjects who demonstrated stable disease over the following six months (ΔFEV1 % predicted = 4.7 ± 7.2; N = 34) were retrospectively compared wi...

Respiratory maneuvers can uncover manifestations of myocardial ischemia. Some pulse wave characteristics are strongly associated with significant coronary artery disease (S-CAD). An innovative test using the respiratory stress response (RSR) has been developed for the detection of S-CAD. It is based on spectral analysis of finger pulse wave oscillations measured by photoplethysmography during deep, paced breathing at a rate of six breaths per minute (0.1 Hz) over 70 s. RSR was assessed, prior to the procedure, in 150 consecutive patients referred for coronary angiography. It was calculated by analyzing the relative spectral power of the respiratory peak area at 0.1 Hz, using proprietary software. The coronary angiograms were analyzed by quantitative coronary angiography by 1 cardiologist who was blinded to the RSR results. S-CAD was defined as luminal stenosis >70% of > or = 1 coronary artery with a diameter > or = 2 mm, or left main stenosis >50%. A valid RSR was obtained in 150 of 153 patients (98%) with a mean age of 58.7 + or - 10.6 years (67% males). S-CAD was found in 36 patients (24%). S-CAD patients had significantly lower RSR compared to patients without S-CAD (6.7% + or - 5.1 vs. 17.4% + or - 10.6; P<.001, respectively). Multivariate logistic regression analysis, adjusted for known CAD risk factors, showed that RSR is a strong independent indicator of S-CAD (odds ratio 41.2, 95% CI 12.2-139.3; P<.001). The innovative RSR test is a simple, noninvasive bedside or office-based tool for the detection of S-CAD.

Greenberg, Harly E., Rammohan S. Rao, Anthony L. Sica, and Steven M. Scharf. Effect of chronic resistive loading on hypoxic ventilatory responsiveness. J. Appl. Physiol. 82(2): 500–507, 1997.—Depression of ventilation mediated by endogenous opioids has been observed acutely after resistive airway loading. We evaluated the effects of chronically increased airway resistance on hypoxic ventilatory responsiveness shortly after load imposition and 6 wk later. A circumferential tracheal band was placed in 200-g rats, tripling tracheal resistance. Sham surgery was performed in controls. Ventilation and the ventilatory response to hypoxia were measured by using barometric plethysmography at 2 days and 6 wk postsurgery in unanesthetized rats during exposure to room air and to 12% O2-5% CO2-balance N2. Trials were performed with and without naloxone (1 mg/kg ip). Room air arterial blood gases demonstrated hypercapnia with normoxia in obstructed rats at 2 days and 6 wk postsurgery. During hypo...

Beta-blockers are commonly prescribed for patients with cardiovascular disease. Providers have been wary of treating chronic obstructive pulmonary disease (COPD) patients with beta-blockers due to concern for bronchospasm, but retrospective studies have shown that cardio-selective beta-blockers are safe in COPD and possibly beneficial. However, these benefits may reflect symptom improvements due to the cardiac effects of the medication. The purpose of this study is to evaluate associations between beta-blocker use and both exacerbation rates and longitudinal measures of lung function in two well-characterized COPD cohorts. We retrospectively analyzed 1219 participants with over 180 days of follow up from the STATCOPE trial, which excluded most cardiac comorbidities, and from the placebo arm of the MACRO trial. Primary endpoints were exacerbation rates per person-year and change in spirometry over time in association with beta blocker use. Overall 13.9% (170/1219) of participants rep...

The cardiac manifestations of chronic obstructive pulmonary disease (COPD) are numerous. Impairments of right ventricular dysfunction and pulmonary vascular disease are well known to complicate the clinical course of COPD and correlate inversely with survival. The pathogenesis of pulmonary vascular disease in COPD is likely multifactorial and related to alterations in gas exchange and vascular biology, as well as structural changes of the pulmonary vasculature and mechanical factors. Several modalities currently exist for the assessment of pulmonary vascular disease in COPD, but right heart catheterization remains the gold standard. Although no specific therapy other than oxygen has been generally accepted for the treatment of pulmonary hypertension in this population, there has been renewed interest in specific pulmonary vasodilators. The coexistence of COPD and coronary artery disease occurs frequently. This association is likely related to shared risk factors as well as similar p...