Polysomnographic Assessment of Sleep Disturbances in Cancer Development: A Historical Multicenter Clinical Cohort Study.

BACKGROUND: Many cellular processes are controlled by sleep. Therefore, alterations in sleep might be expected to stress biological systems that could influence malignancy risk. RESEARCH QUESTION: What is the association between polysomnographic measures of sleep disturbances and incident cancer, and what is the validity of cluster analysis in identifying polysomnography phenotypes? STUDY DESIGN AND METHODS: We conducted a retrospective multicenter cohort study using linked clinical and provincial health administrative data on consecutive adults free of cancer at baseline with polysomnography data collected between 1994 and 2017 in four academic hospitals in Ontario, Canada. Cancer status was derived from registry records. Polysomnography phenotypes were identified by k-means cluster analysis. A combination of validation statistics and distinguishing polysomnographic features was used to select clusters. Cox cause-specific regressions were used to assess the relationship between identified clusters and incident cancer. RESULTS: Among 29,907 individuals, 2,514 (8.4%) received a diagnosis of cancer over a median of 8.0 years (interquartile range, 4.2-13.5 years). Five clusters were identified: mild (mildly abnormal polysomnography findings), poor sleep, severe OSA or sleep fragmentation, severe desaturations, and periodic limb movements of sleep (PLMS). The associations between cancer and all clusters compared with the mild cluster were significant while controlling for clinic and year of polysomnography. When additionally controlling for age and sex, the effect remained significant only for PLMS (adjusted hazard ratio [aHR], 1.26; 95% CI, 1.06-1.50) and severe desaturations (aHR, 1.32; 95% CI, 1.04-1.66). Further controlling for confounders, the effect remained significant for PLMS, but was attenuated for severe desaturations. INTERPRETATION: In a large cohort, we confirmed the importance of polysomnographic phenotypes and highlighted the role that PLMS and oxygenation desaturation may play in cancer. Using this study's findings, we also developed an Excel (Microsoft) spreadsheet (polysomnography cluster classifier) that can be used to validate the identified clusters on new data or to identify which cluster a patient belongs to. TRIAL REGISTRY: ClinicalTrials.gov; Nos.: NCT03383354 and NCT03834792; URL: www. CLINICALTRIALS: gov.

Survival and health care costs after inpatient elective surgery: comparison of patients with and without chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is common among surgical patients, and patients with COPD have higher risk for complications and death within 30 days after surgery. We sought to describe the longer-term postoperative survival and costs of patients with COPD compared with those without COPD within 1 year after inpatient elective surgery. METHODS: In this retrospective population-based cohort study, we used linked health administrative databases to identify all patients undergoing inpatient elective surgery in Ontario, Canada, from 2005 to 2019. We ascertained COPD status using validated definitions. We followed participants for 1 year after surgery to evaluate survival and costs to the health system. We quantified the association of COPD with survival (Cox proportional hazards models) and costs (linear regression model with log-transformed costs) with partial adjustment (for sociodemographic factors and procedure type) and full adjustment (also adjusting for comorbidities). We assessed for effect modification by frailty, cancer and procedure type. RESULTS: We included 932 616 patients, of whom 170 482 (18%) had COPD. With respect to association with risk of death, COPD had a partially adjusted hazard ratio (HR) of 1.61 (95% confidence interval [CI] 1.58-1.64), and a fully adjusted HR of 1.26 (95% CI 1.24-1.29). With respect to impact on health system costs, COPD was associated with a partially adjusted relative increase of 13.1% (95% CI 12.7%-13.4%), and an increase of 4.6% (95% CI 4.3%-5.0%) with full adjustment. Frailty, cancer and procedure type (such as orthopedic and lower abdominal surgery) modified the association between COPD and outcomes. INTERPRETATION: Patients with COPD have decreased survival and increased costs in the year after surgery. Frailty, cancer and the type of surgical procedure modified associations between COPD and outcomes, and must be considered when risk-stratifying surgical patients with COPD.

Health Care Use, Costs, and Survival Trajectory of Home Mechanical Insufflation-Exsufflation.

BACKGROUND: Despite expert recommendations for use, limited evidence identifies effectiveness of mechanical insufflation-exsufflation (MI-E) in addressing respiratory morbidity and resultant health care utilization and costs for individuals with neuromuscular disorders. We examined the impact of provision of publicly funded MI-E devices on health care utilization, health care costs, and survival trajectory. METHODS: This is a retrospective pre/post cohort study linking data on prospectively recruited participants using MI-E to health administrative databases to quantify outcomes. RESULTS: We linked data from 106 participants (8 age < 15 y) and determined annualized health care use pre/post device. We found no difference in emergency department (ED) visit or hospital admission rates. Following MI-E approval, participants required fewer hospital days (median [interquartile range] [IQR]) 0 [0-9] vs 0 [0-4], P = .03). Rates of physician specialist visits also decreased (median IQR 7 [4-11] vs 4 [2-7], P < .001). Conversely, rates of home care nursing and homemaking/personal support visits increased. Following MI-E, total costs were lower for 59.4%, not different for 13.2%, and higher for 27.4%. Physician billing costs decreased whereas home care costs increased. Regression modeling identified pre-MI-E costs were the most important predictor of costs after approval. At 12 months, 23 (21.7%) participants had died. Risk of death was higher for those using more medical devices (hazard ratio 1.12, [95% CI 1.02-1.22]) in the home. CONCLUSIONS: Provision of publicly funded MI-E devices did not influence rates of ED visits or hospital admission but did shift health care utilization and costs from the acute care to community sector. Although increased community costs negated cost savings from physician billings, evidence suggests costs savings from reduced hospital days and fewer specialist visits. Risk of death was highest in individuals requiring multiple medical technologies.

Effects of removing a fee-for-service incentive on specialist chronic disease services: a time-series analysis. / Effets de la suppression des mesures incitatives s'ajoutant à la rémunération à l'acte sur les services spécialisés liés aux maladies chroniques : une analyse des séries chronologiques.

INTRODUCTION: Physician payment models are known to affect the nature and volume of services provided. Our objective was to study the effects of removing a financial incentive, the fee-for-service premium, on the provision of chronic disease follow-up services by internal medicine, cardiology, nephrology and gastroenterology specialists. METHODS: We collected linked administrative health care data for the period 1 April 2013 to 31 March 2017 from databases held at the Institute for Clinical Evaluative Sciences (ICES) in Ontario, Canada. We conducted a time-series analysis before and after the removal of the fee-for-service premium on 1 April 2015. The primary outcome was total monthly visits for chronic disease follow-up services. Secondary outcomes were monthly visits for total follow-up services and new patient consultations. We compared internal medicine, cardiology, nephrology and gastroenterology specialists practising during the study timeframe with respirology, hematology, endocrinology, rheumatology and infectious diseases specialists who remained eligible to claim the premium. We chose this comparison group as these are all subspecialties of internal medicine, providing similar services. RESULTS: The number of chronic disease follow-up visits decreased significantly after removal of the premium, but there was no decrease in total follow-up visits. There was also a significant downward trend in new patient consultations. No changes were observed in the comparison group. CONCLUSION: The decrease in volume of chronic disease follow-up visits can be explained by diagnostic criteria being met less often, rather than an actual reduction in services provided. Potential effects on patient outcomes require further exploration.

Medication Discontinuation in Adults With COPD Discharged From the Hospital: A Population-Based Cohort Study.

BACKGROUND: Patients admitted to the hospital with COPD are commonly managed with inhaled short-acting bronchodilators, sometimes in lieu of the long-acting bronchodilators they take as outpatients. If held on admission, these long-acting inhalers should be re-initiated upon discharge; however, health-care transitions sometimes result in unintentional discontinuation. RESEARCH QUESTION: What is the risk of unintentional discontinuation of long-acting muscarinic antagonist (LAMA) and long-acting beta-agonist and inhaled corticosteroid (LABA-ICS) combination medications following hospital discharge in older adults with COPD? STUDY DESIGN AND METHODS: A retrospective cohort study was conducted by using health administrative data from 2004 to 2016 from Ontario, Canada. Adults with COPD aged ≥ 66 years who had filled prescriptions for a LAMA or LABA-ICS continuously for ≥ 1 year were included. Log-binomial regression models were used to determine risk of medication discontinuation following hospitalization in each medication cohort. RESULTS: Of the 27,613 hospitalization discharges included in this study, medications were discontinued 1,466 times. Among 78,953 patients with COPD continuously taking a LAMA or LABA-ICS, those hospitalized had a higher risk of having medications being discontinued than those who remained in the community (adjusted risk ratios of 1.50 [95% CI, 1.34-1.67; P < .001] and 1.62 [95% CI, 1.39, 1.90; P < .001] for LAMA and LABA-ICS, respectively). Crude rates of discontinuation for people taking LAMAs were 5.2% in the hospitalization group and 3.3% in the community group; for people taking LABA-ICS, these rates were 5.5% in the hospitalization group and 3.1% in the community group. INTERPRETATION: In an observational study of highly compliant patients with COPD, hospitalization was associated with an increased risk of long-acting inhaler discontinuation. These Results suggest a likely larger discontinuation problem among less adherent patients and should be confirmed and quantified in a prospective cohort of patients with COPD and average compliance. Quality improvement efforts should focus on safe transitions and patient medication reconciliation following discharge.

Understanding resource utilization and mortality in COPD to support policy making: A microsimulation study.

Chronic obstructive pulmonary disease (COPD) poses a significant but heterogeneous burden to individuals and healthcare systems. Policymakers develop targeted policies to minimize this burden but need personalized tools to evaluate novel interventions and target them to subpopulations most likely to benefit. We developed a platform to identify subgroups that are at increased risk of emergency department visits, hospitalizations and mortality and to provide stratified patient input in economic evaluations of COPD interventions. We relied on administrative and survey data from Ontario, Canada and applied a combination of microsimulation and multi-state modeling methods. We illustrated the functionality of the platform by quantifying outcomes across smoking status (current, former, never smokers) and by estimating the effect of smoking cessation on resource use and survival, by comparing outcomes of hypothetical cohorts of smokers who quit at diagnosis and smokers that continued to smoke post diagnosis. The cumulative incidence of all-cause mortality was 37.9% (95% CI: 34.9, 41.4) for never smokers, 34.7% (95% CI: 32.1, 36.9) for current smokers, and 46.4% (95% CI: 43.6, 49.0) for former smokers, at 14 years. Over 14 years, smokers who did not quit at diagnosis had 16.3% (95% CI: 9.6, 38.4%) more COPD-related emergency department visits than smokers who quit at diagnosis. In summary, we combined methods from clinical and economic modeling to create a novel tool that policymakers and health economists can use to inform future COPD policy decisions and quantify the effect of modifying COPD risk factors on resource utilization and morality.

Costs of Workplace Productivity Loss in Patients with Connective Tissue Disease-associated Interstitial Lung Disease.

Rationale: Interstitial lung disease (ILD) develops in a large percentage of patients with connective tissue disease (CTD) and is associated with increased morbidity and mortality. Patients with CTD-associated ILD (CTD-ILD) often present at a young age, suggesting that ILD likely impacts workplace productivity.Objectives: We aimed to determine the employment rate and workplace productivity loss, along with its associated factors and estimated costs, in patients with fibrotic CTD-ILD.Methods: Patients with fibrotic CTD-ILD from the six centers of the Canadian Registry for Pulmonary Fibrosis were eligible. Health-related productivity loss was assessed using the Work Productivity and Activity Impairment questionnaire. Proposed factors associated with low workplace productivity were forced into a multivariable regression model. Average productivity loss in hours/week was used to calculate the costs of productivity loss based on hourly wages obtained from national census data matched for age and sex. Workplace productivity loss outcomes were compared between patients with CTD-ILD and patients with a non-CTD fibrotic ILD.Results: Of 375 eligible patients with fibrotic CTD-ILD, 113 (30%) were employed. Productivity loss was reported by 59% of employed patients, with a mean loss of 9.4 ± 1.2 hours/week, including 3.9 ± 0.9 hours/week from absenteeism and 5.5 ± 0.7 hours/week from presenteeism. Employment among patients 25-54 years of age with fibrotic CTD-ILD was 27% lower than that in the matched general Canadian population (56% vs. 83%; P < 0.001). Employment among patients ≥55 years of age with CTD-ILD was 17% lower than that in the matched population (19% vs. 36%; P < 0.001). Workplace productivity loss was not associated with respiratory symptoms or lung physiology. Annual costs of productivity loss were calculated at 13,593 Canadian dollars per employee with fibrotic CTD-ILD. Workplace productivity loss was similar in patients with fibrotic CTD-ILD and those with non-CTD fibrotic ILD.Conclusions: Patients with fibrotic CTD-ILD frequently report workplace productivity loss, which is unexplained by respiratory symptoms or lung physiology and is associated with significant costs.

Trends in prescriptions and costs of inhaled medications in chronic obstructive pulmonary disease: a 19-year population-based study from Canada.

Background: The patterns of medication use in chronic obstructive pulmonary disease (COPD) may change over time due to the availability of new medications, updates in guideline-based recommendations, and changes in patient and care provider preferences. Objectives: To document population-level trends of filled prescriptions and costs for major classes of inhaled COPD therapies. Method: We used administrative health databases of the province of British Columbia, Canada, from 1997 to 2015, to create a retrospective cohort of COPD patients. We documented the percentage of patients receiving major inhaled COPD-related medications, including short-acting beta-2 adrenoreceptor agonists (SABA), long-acting beta-2 adrenoreceptor agonists (LABA), inhaled corticosteroids (ICS), short-acting muscarinic receptor antagonists (SAMA), and long-acting muscarinic receptor antagonists (LAMA). We quantified the average, and relative annual change in, dispensed quantities and costs (in 2015 Canadian dollars [$]) of medications. Combination therapy was assessed as the proportion of time covered by two or more long-acting medications of different classes. Results: A total of 176,338 patients were included in the final cohort (mean age at entry 68.7, 48.5% female). In 2015, the most common medication was ICS (45.7% of the patients), followed by LABA (36.5%). LAMA was the least used medication (18.9%). The number of filled prescriptions per patient per year for LAMA (+7.8% per year) and LABA (+4.9%) increased, while they decreased for SAMA (-6.3%) and SABA (-3.8%), and remained relatively constant for ICS. The average annual per-patient costs of inhaled medications were $570.8 in 2015, which was double the costs from 1997. Single-inhaler ICS/LABA had the highest rate of increase (11.6% per year), and comprised 53.7% of the total costs of inhalers in 2015. In 2015, 28.5% of the patient time was on combination therapies, with 7.1% on triple ICS/LABA/LAMA therapy. Conclusion: Utilization of inhaled therapies for COPD has changed significantly over time. The low utilization of LAMA and high utilization of combination therapies (particularly those containing ICS) do not seem to be aligned with COPD treatment guidelines.

End-of-life care in individuals with respiratory diseases: a population study comparing the dying experience between those with chronic obstructive pulmonary disease and lung cancer.

Purpose: Among individuals with COPD and/or lung cancer, to describe end-of-life health service utilization, costs, and place of death; to identify predictors of home palliative care use, and to assess benefits associated with palliative care use. Patients and methods: We conducted a retrospective population-based study using provincial linked health administrative data (Ontario, Canada) between 2010 and 2015. We examined health care use in the last 90 days of life in adults 35 years and older with physician-diagnosed COPD and/or lung cancer identified using a validated algorithm and the Ontario Cancer Registry, respectively. Four mutually exclusive groups were considered: (i) COPD only, (ii) lung cancer only, (iii) COPD and lung cancer, and (iv) neither COPD nor lung cancer. Multivariable generalized linear models were employed. Results: Of 445,488 eligible deaths, 34% had COPD only, 4% had lung cancer only, 5% had both and 57% had neither. Individuals with COPD only received less palliative care (20% vs 57%) than those with lung cancer only. After adjustment, people with lung cancer only were far more likely to receive palliative care (OR=4.22, 4.08-4.37) compared to those with neither diagnosis, while individuals with COPD only were less likely to receive palliative care (OR=0.82, 0.81-0.84). Home palliative care use was associated with reduced death and fewer days in acute care, and less cost, regardless of the diagnosis. Conclusion: Although individuals with lung cancer were much more likely to receive palliative care than those with COPD, both populations were underserviced. Results suggest greater involvement of palliative care may improve the dying experience of these populations and reduce costs.

Patterns of health care use related to respiratory conditions in early life: A birth cohort study with linked administrative data.

OBJECTIVES: To identify distinctive patterns of respiratory-related health services use (HSU) between birth and 3 years of age, and to examine associated symptom and risk profiles. METHODS: This study included 729 mother and child pairs enrolled in the Toronto site of the Canadian Healthy Infant Longitudinal Development study in 2009-2012; they were linked to Ontario health administrative databases (2009-2016). A model-based cluster analysis was performed to identify distinct groups of children who followed a similar pattern of respiratory-related HSU between birth and 3 years of age, regarding hospitalization, emergency department (ED) and physician office visits for respiratory conditions and total health care costs (2016 Canadian dollars). RESULTS: The majority (estimated cluster weight = 0.905) showed a pattern of low and stable respiratory care use (low HSU) while the remainder (weight = 0.095) showed a pattern of high use (high HSU). From 0 to 3 years of age, the low- and high-HSU groups differed in mean trajectories of total health care costs ($783 per 6 months decreased to $114, vs $1796 to $177, respectively). Compared to low-HSU, the high-HSU group was associated with a constant risk of hospitalizations, early high ED utilization and physician visits for respiratory problems. The two groups differed significantly in the timing of wheezing (late onset in low-HSU vs early in high-HSU) and future total costs (stable vs increased). CONCLUSIONS: One in ten children had high respiratory care use in early life. Such information can help identify high-risk young children in a large population, monitor their long-term health, and inform resource allocation.

Costs of Workplace Productivity Loss in Patients With Fibrotic Interstitial Lung Disease.

BACKGROUND: Fibrotic interstitial lung diseases (ILDs) are highly morbid chronic disorders that frequently occur in working age individuals. The goal of this study was to determine workplace productivity loss, its determinants, and its estimated costs in patients with fibrotic ILD. METHODS: Patients with idiopathic pulmonary fibrosis, chronic hypersensitivity pneumonitis, idiopathic nonspecific interstitial pneumonia, or unclassifiable ILD were identified from the six-center Canadian Registry for Pulmonary Fibrosis (CARE-PF). The Work Productivity and Activity Impairment questionnaire was used to determine health-related productivity loss. Independent predictors of low workplace productivity were identified by using multivariate regression. Patient data were compared with Canadian population census data. The average productivity loss (hours per week) and the individual's hourly wage were used to estimate the costs of productivity loss. RESULTS: Of 650 eligible patients, 148 (23%) were employed. Productivity loss was reported by 55% of employed patients with an average productivity loss of 7.8 ± 0.9 h per week (2.3 ± 0.6 h per week related to absenteeism and 5.5 ± 0.6 h per week related to presenteeism). Employment among patients with ILD aged 25 to 54 years was 23% lower than the age- and sex-matched general Canadian population (60% vs 83%; P < .001). Employment among patients with ILD aged ≥ 55 years was 18% lower than in the age- and sex-matched population (20% vs 38%; P < .001). Dyspnea and cough were independent predictors of workplace productivity loss. Estimated annual costs of productivity loss were 11,610 Canadian dollars per employee with ILD. CONCLUSIONS: Workplace productivity loss is common in fibrotic ILD, strongly correlated with symptom severity, and associated with significant cost.

Reducing Chronic Obstructive Pulmonary Disease Hospital Readmissions. An Official American Thoracic Society Workshop Report.

Chronic obstructive pulmonary disease (COPD) is the third leading cause of hospital readmissions in the United States. The quality of care delivered to patients with COPD is known to be lacking across the care continuum, and may contribute to high rates of readmission. As part of the response to these issues, the Centers for Medicare and Medicaid instituted a penalty for 30-day readmissions as part of their Hospital Readmission Reduction Program in October 2014. At the time the penalty was instated, there was little published evidence on effective hospital-based programs to reduce readmissions after acute exacerbations of COPD. Even now, several years later, few published programs exist, and we continue to lack consistent approaches that lead to improved readmission rates. In addition, there was concern that the penalty would widen health disparities. Despite the dearth of published evidence to reduce readmissions beyond available COPD guidelines, many hospitals across the United States began to develop and implement programs, based on little evidence, due to the financial penalty. We, therefore, assembled a diverse group of clinicians, researchers, payers, and program leaders from across the country to present and discuss approaches that had the greatest potential for success. We drew on expertise from ongoing readmission reduction programs, implementation methodologies, and stakeholder perspectives to develop this Workshop Report on current best practices and models for addressing COPD hospital readmissions.

Procedure volume and mortality after surgical lung biopsy in interstitial lung disease.

Surgical volume-outcome relationships are well established but have not been studied in patients with interstitial lung disease (ILD) undergoing surgical lung biopsy (SLB). Our study objective was to determine if hospital SLB volume is associated with post-operative mortality in patients with ILD.A cohort study using administrative, population-based data from Ontario, Canada was performed in adults with ILD who underwent a SLB between 2001 and 2014. The association between yearly hospital SLB volume and 30-day post-operative mortality was assessed using multilevel logistic regression modelling.3057 surgical lung biopsies for ILD were performed during the study period with a median (interquartile range) yearly hospital volume of 73 (34-143) procedures. 30-day mortality was 7.1%, 20.2% and 1.9% in overall, nonelective and elective patients, respectively. Higher yearly hospital SLB volume was associated with lower odds of 30-day post-operative mortality after adjusting for patient characteristics (OR 0.84, 95% CI 0.73-0.97; p=0.02), with the association appearing stronger for nonelective versus elective procedures (OR 0.84, 95% CI 0.69-1.02; p=0.08 versus OR 0.94, 95% CI 0.74-1.18; p=0.57).Higher yearly hospital SLB volume was associated with lower post-operative mortality in patients with ILD, with the association appearing to be mainly driven by nonelective cases. SLB mortality was significantly higher for nonelective cases.

Improving the Affordability of Prescription Medications for People with Chronic Respiratory Disease. An Official American Thoracic Society Policy Statement.

BACKGROUND: Mounting evidence indicates that out-of-pocket costs for prescription medications, particularly among low- and middle-income patients with chronic diseases, are imposing financial burden, reducing medication adherence, and worsening health outcomes. This problem is exacerbated by a paucity of generic alternatives for prevalent lung diseases, such as asthma and chronic obstructive pulmonary disease, as well as high-cost medicines for rare diseases, such as cystic fibrosis. Affordability and access challenges are especially salient in the United States, as citizens of many other countries pay lower prices for and have greater access to prescription medications. METHODS: The American Thoracic Society convened a multidisciplinary committee comprising experts in health policy pharmacoeconomics, behavioral sciences, and clinical care, along with individuals providing industry and patient perspectives. The report and its recommendation were iteratively developed over a year of in-person, telephonic, and electronic deliberation. RESULTS: The committee unanimously recommended the establishment of a publicly funded, politically independent, impartial entity to systematically draft evidence-based pharmaceutical policy recommendations. The goal of this entity would be to generate evidence and action steps to ensure people have equitable and affordable access to prescription medications, to maximize the value of public and private pharmaceutical expenditures on health, to support novel drug development within a market-based economy, and to preserve clinician and patient choice regarding personalized treatment. An immediate priority is to examine the evidence and make recommendations regarding the need to have essential medicines with established clinical benefit from each drug class in all Tier 1 formularies and propose recommendations to reduce barriers to timely generic drug availability. CONCLUSIONS: By making explicit, evidence-based recommendations, the entity can support the establishment of coherent national policies that expand access to affordable medications, improve the health of patients with chronic disease, and optimize the use of public and private resources.

Risk Trajectories of Readmission and Death in the First Year after Hospitalization for Chronic Obstructive Pulmonary Disease.

RATIONALE: Characterization of the dynamic nature of posthospital risk in chronic obstructive pulmonary disease (COPD) is needed to provide counseling and plan clinical services. OBJECTIVES: To analyze risk of readmission and death after discharge for COPD among Medicare beneficiaries aged 65 years and older and to determine the association between ventilator support and risk trajectory. METHODS: We computed daily absolute risks of hospital readmission and death for 1 year after discharge for COPD, stratified by ventilator support. We determined the time required for risks to decline by 50% from maximum daily values after discharge and for daily risks to plateau. We compared risks with those found in the general elderly population. MEASUREMENTS AND MAIN RESULTS: Among 2,340,637 hospitalizations, the readmission rate at 1 year was 64.2%, including 63.5%, 66.0%, and 64.1% among those receiving invasive, noninvasive, and no ventilation, respectively. Among 1,283,069 hospitalizations, mortality at 1 year was 26.2%, including 45.7%, 41.8%, and 24.4% among those same respective groups. Daily risk of readmission declined by 50% within 28, 39, and 43 days and plateaued at 46, 54, and 61 days among those receiving invasive, noninvasive, and no ventilation, respectively. Risk of death declined by 50% by 3, 4, and 17 days and plateaued by 21, 18, and 24 days in the same respective groups. Risks of hospitalization and death were significantly higher after discharge for COPD than among the general Medicare population. CONCLUSIONS: Discharge from the hospital is associated with prolonged risks of readmission and death that vary with need for ventilator support. Interventions limited to the first month after discharge may be insufficient to improve longitudinal outcomes.

Forecasting Hospitalization and Emergency Department Visit Rates for Chronic Obstructive Pulmonary Disease. A Time-Series Analysis.

RATIONALE: Knowing trends in and forecasting hospitalization and emergency department visit rates for chronic obstructive pulmonary disease (COPD) can enable health care providers, hospitals, and health care decision makers to plan for the future. OBJECTIVES: We conducted a time-series analysis using health care administrative data from the Province of Ontario, Canada, to determine previous trends in acute care hospitalization and emergency department visit rates for COPD and then to forecast future rates. METHODS: Individuals aged 35 years and older with physician-diagnosed COPD were identified using four universal government health administrative databases and a validated case definition. Monthly COPD hospitalization and emergency department visit rates per 1,000 people with COPD were determined from 2003 to 2014 and then forecasted to 2024 using autoregressive integrated moving average models. RESULTS: Between 2003 and 2014, COPD prevalence increased from 8.9 to 11.1%. During that time, there were 274,951 hospitalizations and 290,482 emergency department visits for COPD. After accounting for seasonality, we found that monthly COPD hospitalization and emergency department visit rates per 1,000 individuals with COPD remained stable. COPD prevalence was forecasted to increase to 12.7% (95% confidence interval [CI], 11.4-14.1) by 2024, whereas monthly COPD hospitalization and emergency department visit rates per 1,000 people with COPD were forecasted to remain stable at 2.7 (95% CI, 1.6-4.4) and 3.7 (95% CI, 2.3-5.6), respectively. Forecasted age- and sex-stratified rates were also stable. CONCLUSIONS: COPD hospital and emergency department visit rates per 1,000 people with COPD have been stable for more than a decade and are projected to remain stable in the near future. Given increasing COPD prevalence, this means notably more COPD health service use in the future.

Progression from Asthma to Chronic Obstructive Pulmonary Disease. Is Air Pollution a Risk Factor?

RATIONALE: Individuals with asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS), have more rapid decline in lung function, more frequent exacerbations, and poorer quality of life than those with asthma or COPD alone. Air pollution exposure is a known risk factor for asthma and COPD; however, its role in ACOS is not as well understood. OBJECTIVES: To determine if individuals with asthma exposed to higher levels of air pollution have an increased risk of ACOS. METHODS: Individuals who resided in Ontario, Canada, aged 18 years or older in 1996 with incident asthma between 1996 and 2009 who participated in the Canadian Community Health Survey were identified and followed until 2014 to determine the development of ACOS. Data on exposures to fine particulate matter (PM2.5) and ozone (O3) were obtained from fixed monitoring sites. Associations between air pollutants and ACOS were evaluated using Cox regression models. MEASUREMENTS AND MAIN RESULTS: Of the 6,040 adults with incident asthma who completed the Canadian Community Health Survey, 630 were identified as ACOS cases. Compared with those without ACOS, the ACOS population had later onset of asthma, higher proportion of mortality, and more frequent emergency department visits before COPD diagnosis. The adjusted hazard ratios of ACOS and cumulative exposures to PM2.5 (per 10 µg/m(3)) and O3 (per 10 ppb) were 2.78 (95% confidence interval, 1.62-4.78) and 1.31 (95% confidence interval, 0.71-2.39), respectively. CONCLUSIONS: Individuals exposed to higher levels of air pollution had nearly threefold greater odds of developing ACOS. Minimizing exposure to high levels of air pollution may decrease the risk of ACOS.

History of Asthma in Patients with Chronic Obstructive Pulmonary Disease. A Comparative Study of Economic Burden.

RATIONALE: A diagnosis of asthma is considered an independent risk factor for chronic obstructive pulmonary disease (COPD). However, little is known about health service use patterns in patients with COPD who have a history of asthma in comparison with those without such a history, especially regarding comorbid conditions. OBJECTIVES: To estimate the excess costs of COPD in patients with a history of asthma (COPD+asthma) versus those with COPD without such a history (COPD-only); to estimate excess costs attributable to inpatient care, outpatient care, medications, and community care; and to estimate excess costs attributable to comorbid conditions. METHODS: We used vital statistics, inpatient and outpatient encounters, filled prescription records, and community care data of patients in British Columbia, Canada, from 1997 to 2012 to create propensity score-matched COPD+asthma and COPD-only cohorts. We calculated and compared the excess medical costs (in 2012 Canadian dollars [$]) between the two groups on the basis of billing information. Comorbidities were ascertained from the inpatient and outpatient records and were classified on the basis of major categories of the International Classification of Diseases, 10th Revision. MEASUREMENTS AND MAIN RESULTS: The final sample consisted of 22,565 individuals within each group (mean age at baseline, 67.9 yr; 57.0% female; average follow-up, 4.07 yr). Excess costs of COPD+asthma were $540.7 per patient-year (PY) (95% confidence interval [CI], $301.7-$779.8; P < 0.001). Costs of medications ($657.9/PY; P < 0.001) and outpatient services ($127.6/PY; P < 0.001) were higher in COPD+asthma, but costs of hospitalizations were lower (-$271.0/PY; P = 0.002). Community care costs in the two groups were similar (P = 0.257). The excess cost of respiratory-related conditions was $856.2/PY (P < 0.001), with $552.6/PY being due to respiratory-related medications (P < 0.001); costs of all other conditions combined were lower in COPD+asthma, mainly due to lower costs of cardiovascular diseases (-$201.8/PY; P < 0.001). CONCLUSIONS: Patients with COPD with a previous history of asthma consume more health care resources than those with COPD alone, but there are important differences in cost components and costs attributable to comorbid conditions. Further research is required to examine whether the lower costs of cardiovascular disease in these patients is due to lower levels of related risk factors or to intrinsic differences in COPD phenotypes.

The Effect of Patient Neighborhood Income Level on the Purchase of Continuous Positive Airway Pressure Treatment among Patients with Sleep Apnea.

RATIONALE: The cost of continuous positive airway pressure (CPAP) treatment for patients with low socioeconomic status may be an important barrier to successful treatment of obstructive sleep apnea under a copayment health care system. OBJECTIVES: We evaluated an association between patient neighborhood income level and the purchase of a CPAP device under a cost-sharing health care insurance system. METHODS: All adults who underwent a first diagnostic sleep study at St. Michael's Hospital (Toronto, ON, Canada) between 2004 and 2010 were included. Severity of obstructive sleep apnea was determined by the apnea-hypopnea index (AHI) and level of daytime sleepiness (by the Epworth Sleepiness Scale). Patient data were linked to provincial health administrative data from 1991 to 2013 to determine the purchase of CPAP equipment, comorbidities, neighborhood income, and rural status at baseline. Neighborhood income was categorized into quintiles, ranked from poorest (Q1) to wealthiest (Q5). Assuming that the majority of participants with severe obstructive sleep apnea (AHI > 30 events/h) and excessive daytime sleepiness (Epworth Sleepiness Scale ≥ 10) would have been strongly recommended CPAP, we evaluated the association between patient neighborhood income and purchase of a CPAP device in this group via multivariable Cox regressions. MEASUREMENTS AND MAIN RESULTS: Of the 695 participants with severe obstructive sleep apnea and excessive daytime sleepiness, 400 (58%) purchased a CPAP device. Patients who accepted CPAP were more likely to live in a higher-income neighborhood. Cumulative incidence of CPAP acceptance at 6 months was 43% for individuals in a low-income neighborhood (Q1) and 52% in combined higher-income neighborhoods (Q2-5) (P = 0.05). Controlling for sex and age, living in higher-income neighborhoods was associated with a 27% increased chance of accepting CPAP compared with the lowest-income neighborhood (hazard ratio Q2-5 vs. Q1, 1.27; 95% confidence interval, 0.98-1.64; P = 0.07). CONCLUSIONS: Living in an unfavorable neighborhood is not an obstacle to CPAP treatment among symptomatic patients with severe obstructive sleep apnea under a copayment health care system. However, a potential 27% improvement in CPAP acceptance associated with higher neighborhood income is not inconsequential. Also, the overall CPAP acceptance rate was relatively low, suggesting that obstacles other than finances are primarily responsible.