Predicting Acute Exacerbations in Chronic Obstructive Pulmonary Disease.

BACKGROUND: With increasing health care costs that have outpaced those of other industries, payers of health care are moving from a fee-for-service payment model to one in which reimbursement is tied to outcomes. Chronic obstructive pulmonary disease (COPD) is a disease where this payment model has been implemented by some payers, and COPD exacerbations are a quality metric that is used. Under an outcomes-based payment model, it is important for health systems to be able to identify patients at risk for poor outcomes so that they can target interventions to improve outcomes. OBJECTIVE: To develop and evaluate predictive models that could be used to identify patients at high risk for COPD exacerbations. METHODS: This study was retrospective and observational and included COPD patients treated with a bronchodilator-based combination therapy. We used health insurance claims data to obtain demographics, enrollment information, comorbidities, medication use, and health care resource utilization for each patient over a 6-month baseline period. Exacerbations were examined over a 6-month outcome period and included inpatient (primary discharge diagnosis for COPD), outpatient, and emergency department (outpatient/emergency department visits with a COPD diagnosis plus an acute prescription for an antibiotic or corticosteroid within 5 days) exacerbations. The cohort was split into training (75%) and validation (25%) sets. Within the training cohort, stepwise logistic regression models were created to evaluate risk of exacerbations based on factors measured during the baseline period. Models were evaluated using sensitivity, specificity, and positive and negative predictive values. The base model included all confounding or effect modifier covariates. Several other models were explored using different sets of observations and variables to determine the best predictive model. RESULTS: There were 478,772 patients included in the analytic sample, of which 40.5% had exacerbations during the outcome period. Patients with exacerbations had slightly more comorbidities, medication use, and health care resource utilization compared with patients without exacerbations. In the base model, sensitivity was 41.6% and specificity was 85.5%. Positive and negative predictive values were 66.2% and 68.2%, respectively. Other models that were evaluated resulted in similar test characteristics as the base model. CONCLUSIONS: In this study, we were not able to predict COPD exacerbations with a high level of accuracy using health insurance claims data from COPD patients treated with bronchodilator-based combination therapy. Future studies should be done to explore predictive models for exacerbations. DISCLOSURES: No outside funding supported this study. Samp is now employed by, and owns stock in, AbbVie. The other authors have nothing to disclose. Study concept and design were contributed by Joo and Pickard, along with the other authors. Samp and Lee performed the data analysis, with assistance from the other authors. Samp wrote the manuscript, which was revised by Schumock and Calip, along with the other authors.

Determinants of spirometry use and accuracy of COPD diagnosis in primary care.

BACKGROUND: It is unclear if primary care physicians are following guidelines or using other patient characteristics and factors to determine when to perform spirometry in patients at risk for COPD. It is also unclear to what degree a diagnosis of COPD is accurately reflected by spirometry results. OBJECTIVES: To examine characteristics associated with use of spirometry in primary care for patients with increased risk for COPD and to determine the accuracy of COPD diagnosis in patients with spirometry. DESIGN: Retrospective cohort study. SUBJECTS: A cohort that met the following criteria was identified: ≥35 years of age; ≥ 2 primary care visits in internal medicine clinic in 2007; at least one respiratory or smoking cessation medication, or diagnosis of COPD or shortness of breath or dyspnea in 2007. MAIN MEASURES: Medical records of all primary care physician visits prior to the time of inclusion in 2007 were reviewed. Data on patient demographics, co-morbidities, respiratory medication use, presence of symptoms, history of tobacco use, and pulmonary function tests were extracted. KEY RESULTS: A total 1052 patients were identified. Dyspnea on exertion (Adjusted odds ratio (AOR) 1.52 [95% CI 1.06-2.18]) and chronic cough (AOR 1.71 [1.07-2.72]) were the only chronic symptoms associated with use of spirometry. Current (AOR 1.54 [0.99-2.40]) or past smoking (AOR 1.09 [0.72-1.65]) status were not associated with use of spirometry. Of the 159 patients with a diagnosis of COPD, 93 (58.5%) met GOLD criteria and 81(50.9%) met lower limit of normal (LLN) criteria for COPD. CONCLUSION: Clinicians use spirometry more often among patients with symptoms suggestive of COPD but not more often among patients with current or past tobacco use. For patients who had a spirometry and a diagnosis of COPD, primary care physicians were accurate in their diagnosis only half of the time.

Patterns of healthcare utilization by COPD severity: a pilot study.

Global Initiative on Chronic Obstructive Lung Disease (GOLD) guidelines recently removed stage 0, a group with symptoms but without airways obstruction, from their severity staging. However, in practice this group may still be diagnosed and medically managed. The aim of this study was to characterize healthcare utilization patterns of chronic obstructive pulmonary disease (COPD) patients by disease severity, focusing on the possible unique attributes of patients who would have been classified as GOLD stage 0. This is a prospective cohort pilot study performed at the Hines Veterans Administration Hospital. One hundred twenty patients with a diagnosis of COPD were enrolled. The participants completed quality-of-life questionnaires and a pulmonary function test. Healthcare utilization data were obtained 1 year prior and 2 years after the enrollment date. Three disease severity groups were defined based on GOLD criteria for comparison [GOLD stage 1-2 (GS 1-2), GOLD stage 3-4 (GS 3-4), and formerly GOLD stage 0 ("at risk")]. The "at risk" group had an average of 14.4 (SD = 30.5) outpatient visits/year and 0.3 (SD = 0.8) hospitalizations/year, which were higher than the other groups, but this was not statistically significant. Respiratory medications were used by 6 (26%), 30 (59%), and 40 (91%) patients from "at risk" to GS 3-4, respectively. Patients in the "at risk" group had a decrement in health status, significant utilization of healthcare services, and were often receiving medications not consistent with guidelines.

Sleep apnea in an urban public hospital: assessment of severity and treatment adherence.

OBJECTIVE: To assess obstructive sleep apnea (OSA) severity, continuous positive airway pressure (CPAP) adherence, and factors associated with CPAP adherence among a group of patients with OSA receiving care at a publicly funded county hospital. STUDY DESIGN AND SETTING: A retrospective cohort study in a 464-bed urban public hospital in Cook County, Illinois. RESULTS: A total of 507 patients were included. They had a mean (SD) age of 46.9(11) years, mean body mass index of 46.2 (11.0) kg/m2; mean and median baseline apnea-hypopnea index (AHI) of 71.0 (44.4) and 69.5 episodes/h; mean Epworth Sleepiness Scale (ESS) score of 15.8 (6.1). Of these patients, 53% were men, 74% did not have health insurance coverage, and 77% were African American. Mean CPAP adherence of the 323 patients with follow-up data was 3.87 (2.62) hours/ day, with 47.7% of subjects using CPAP objectively for > or = 4 hours/day. Women were 2.49 (95% CI, 1.39-4.46) times more likely to be nonadherent than men, after adjusting for race, marital status, and age. Of the 172 patients who did not follow up, there were disproportionately more men. When individuals without follow-up were assumed to be nonadherent, the overall compliance rate was 30.4%, and women were 1.72 (95% CI, 1.03-2.88) times more likely to be noncompliant than men, adjusting for race, marital status, and age. CONCLUSION: This study population experienced severe OSA. CPAP adherence was low, with women having a higher likelihood of nonadherence than men. With the epidemic of obesity and increased awareness of OSA, this population should be further studied to diminish future health disparities in the treatment of this disease.