Min J. Joo

The validity of using ICD-9 codes and pharmacy records to identify patients with chronic obstructive pulmonary disease

BackgroundAdministrative data is often used to identify patients with chronic obstructive pulmonary disease (COPD), yet the validity of this approach is unclear. We sought to develop a predictive model utilizing administrative data to accurately identify patients with COPD.MethodsSequential logistic regression models were constructed using 9573 patients with postbronchodilator spirometry at two Veterans Affairs medical centers (2003-2007). COPD was defined as: 1) FEV1/FVC <0.70, and 2) FEV1/FVC < lower limits of normal. Model inputs included age, outpatient or inpatient COPD-related ICD-9 codes, and the number of metered does inhalers (MDI) prescribed over the one year prior to and one year post spirometry. Model performance was assessed using standard criteria.Results4564 of 9573 patients (47.7%) had an FEV1/FVC < 0.70. The presence of ≥1 outpatient COPD visit had a sensitivity of 76% and specificity of 67%; the AUC was 0.75 (95% CI 0.74-0.76). Adding the use of albuterol MDI increased the AUC of this model to 0.76 (95% CI 0.75-0.77) while the addition of ipratropium bromide MDI increased the AUC to 0.77 (95% CI 0.76-0.78). The best performing model included: ≥6 albuterol MDI, ≥3 ipratropium MDI, ≥1 outpatient ICD-9 code, ≥1 inpatient ICD-9 code, and age, achieving an AUC of 0.79 (95% CI 0.78-0.80).ConclusionCommonly used definitions of COPD in observational studies misclassify the majority of patients as having COPD. Using multiple diagnostic codes in combination with pharmacy data improves the ability to accurately identify patients with COPD.

Geographic Variation of Spirometry Use in Newly Diagnosed COPD

BACKGROUND Studies indicate that not all physicians in clinical practice use spirometry routinely in the diagnosis of COPD. Understanding the patterns of spirometry use across geographic regions in patients with newly diagnosed COPD may help to identify the factors associated with the use of spirometry and to improve the quality of COPD care. The objective of this study was to characterize the regional variation in spirometry use for patients with newly diagnosed COPD using the Healthcare Effectiveness Data and Information Set (HEDIS) 2006 spirometry performance measure. METHODS We identified patients within the Veteran Health Administration who were >42 years of age who had received a new diagnosis of COPD between July 2003 and June 2004. The date of the COPD diagnosis was the index date. Spirometry use from 760 days prior to the index date to 180 days after the index date was identified. The Veterans Integrated Service Networks (VISNs) was used as the geographic unit for comparison. RESULTS Of the 93,724 patients included in the study, 36.7% underwent spirometry during the study period. Using the largest VISN as the referent, there was more than a threefold difference in the adjusted odds ratios (AORs) for spirometry use between the regions with the lowest use (AOR, 0.52; 95% confidence interval [CI], 0.48 to 0.57) and the highest use (AOR, 1.61; 95% CI, 1.46 to 1.78). CONCLUSIONS Overall, the use of spirometry in patients with newly diagnosed COPD was low using the new HEDIS spirometry measure with a significant regional variation comprising a more than threefold difference between the regions with the lowest and highest rates of spirometry use.

Inhaled corticosteroids and risk of pneumonia in newly diagnosed COPD

INTRODUCTION The use of inhaled corticosteroids (ICS) in COPD may be associated with an increased risk of pneumonia. Little is known of this risk in newly diagnosed COPD patients. The objective of this study was to determine if the use of ICS among newly diagnosed COPD patients is associated with an increased risk of pneumonia hospitalizations. METHODS Using data from the Department of Veterans Affairs and Centers for Medicare and Medicaid Services, a nested case-control study was performed. We identified patients 65 years of age or older with a new diagnosis of COPD from 1998 to 2002. A total of 145,586 patients were identified. Cases were defined based on hospitalization for pneumonia and exposure was prior use of ICS. Up to 10 controls were matched for each case based on age, sex, month and year of the case. The association between ICS use and pneumonia was evaluated with conditional logistic regression controlling for age, comorbidities, medication classes associated with the risk of pneumonia, and markers of COPD severity. RESULTS There were 13,995 cases of pneumonia. The cohort was predominantly male with an average age of 75.1 (SD=5.4) years. The rate of pneumonia was 6.4 per 100 person-years. After adjustment for covariates, patients with current use of ICS were 1.38 (95% CI, 1.31-1.45) times more likely to have a hospitalization for pneumonia than those without current use of ICS. CONCLUSIONS The use of ICS among patients with newly diagnosed COPD is associated with an increased risk of hospitalization for pneumonia.

Interventions to Reduce Rehospitalizations after Chronic Obstructive Pulmonary Disease Exacerbations. A Systematic Review

RATIONALE Approximately 20% of patients hospitalized for COPD exacerbations in the United States will be readmitted within 30 days. The Centers for Medicare and Medicaid Services has recently proposed to revise the Hospital Readmissions Reduction Program to financially penalize hospitals with high all-cause 30-day rehospitalization rates after a hospitalization for COPD exacerbation on or after October 1, 2014. OBJECTIVES To report the results of a systematic review of randomized clinical trials evaluating interventions to reduce the rehospitalizations after COPD exacerbations. METHODS Multiple electronic databases were systematically searched to identify relevant studies published between January 1966 and June 2013. Titles, abstracts, and, subsequently, full-text articles were assessed for eligibility. Each study was appraised using predefined criteria. MEASUREMENTS AND MAIN RESULTS Among 913 titles and abstracts screened, 5 studies (1,393 participants) met eligibility criteria. All studies had a primary outcome of rehospitalization at 6 or 12 months. No study examined 30-day rehospitalization as the primary outcome. Each study tested a different set of interventions. Two studies (one conducted in Canada and one conducted in Spain and Belgium) showed a decrease in all-cause rehospitalization over 12 months in the intervention group versus comparator group (mean number of hospitalizations per patient, 1.0 vs. 1.8; P = 0.01; percent hospitalized, 45 vs. 67%; P = 0.028; respectively). The only study conducted in the United States found a greater than twofold higher risk of mortality in the intervention group (17 vs. 7%, P = 0.003) but no significant difference in rehospitalizations. It was unclear which set of interventions was effective or harmful. CONCLUSIONS The evidence base is inadequate to recommend specific interventions to reduce rehospitalizations in this population and does not justify penalizing hospitals for high 30-day rehospitalization rates after COPD exacerbations.

Association between Leukotriene-Modifying Agents and Suicide: What is the Evidence?

The US FDA has issued safety alerts and required manufacturers of leukotriene-modifying agents (LTMAs), including montelukast, zafirlukast and zileuton, to include suicide and neuropsychiatric events as a precaution in the drug label. This paper reviews the existing evidence on the potential association between the LTMAs and suicidal behaviour. We conducted a literature search of MEDLINE, EMBASE and International Pharmaceutical Abstracts from 1995 to 2010 (inclusive) to identify pertinent studies and reports. We also examined data obtained from the FDA adverse event reporting system. To date, there are no well conducted, comparative, observational studies of this association, and the safety alerts are based primarily on case reports. While the FDA safety alerts apply to all three LTMAs, montelukast (known by its trade name Singulair®) is by far the most widely used of these drugs and most of the reports to date regarding suicide pertain to montelukast. From 1998 to 2009 there were 838 suicide-related adverse events associated with leukotrienes reported to the FDA, of which all but five involved montelukast. Nearly all cases were reported in 2008 and 2009 (96.1%) after the FDA warnings. LTMAs are approved for use in asthma and allergic rhinitis, and are effective drugs. Both of these diseases are also associated with suicide, making confirmation of the association more difficult. Given the lack of good evidence, we recommend that a large observational cohort or casecontrol study be conducted to quantify the association between LTMAs and suicide. Until then, when prescribing LTMAs, clinicians should consider the potential for suicide and monitor patients who may be at elevated risk carefully for suicidal ideation or psychiatric symptoms associated with suicidal behaviour.

Risk of suicide attempt in asthmatic children and young adults prescribed leukotriene-modifying agents: A nested case-control study

BACKGROUND The US Food and Drug Administration has issued safety alerts about leukotriene receptor-modifying agents and suicidality/suicide, but because these were based on case reports, there is controversy about the association. OBJECTIVE We conducted a nested case-control study to determine the association between leukotriene-modifying agents (LTMAs) and attempted suicide among asthmatic children and young adults. METHODS Cases and control subjects were from a cohort of asthmatic patients aged 5 to 24 years who were new users of LTMAs or other asthma medications. Data were from an insurance claims database. Cases were defined as those with a suicide attempt (SA) occurring after exposure to asthma medication. Control subjects were persons at risk and were selected by using incidence density sampling in a 10:1 match. Conditional logistic regression was used to determine the association between LTMA exposure and the risk of attempted suicide adjusted for important covariates. RESULTS We identified 344 cases and 3438 matched control subjects. Cases were more likely than control subjects to have risk factors for suicide. We found that current use of any LTMA was not associated with increased risk of an SA; in fact, the direction of effect was the opposite (adjusted odd ratio, 0.70; 95% CI, 0.36-1.39). CONCLUSION In this analysis we found that use of LTMAs was not associated with an increased risk of SAs in children, adolescents, and young adults with asthma. Further research needs to be conducted to more fully understand the association between LTMAs and suicide, particularly in subpopulations.

Geographic Variation in Chronic Obstructive Pulmonary Disease Exacerbation Rates

Exacerbations are important disease events for patients with chronic obstructive pulmonary disease (COPD) as they are relatively frequent, result in significant resource use and can indicate worsening disease. Little is known about variation in COPD exacerbation rates across a health system in various geographic regions. To compare COPD exacerbation rates by regional service networks called Veterans Integrated Service Network (VISN) in the Veterans Health Administration (VA) system. Retrospective, observational study. Patients with a COPD diagnosis from October 1999 to September 2000 with follow-up to September 2002. Acute exacerbations of COPD during the baseline and follow-up periods. A total of 198,981 patients were identified. Average exacerbation rate at baseline was 0.503 events per person per year. In the follow-up period, there were 187,686 exacerbations experienced by 87,494 persons (44.0% of cohort). During follow-up, the average adjusted exacerbation rate was 0.589 per person per year and varied from 0.335 (95% CI, 0.328–0.342) in VISN 1 to 0.749 (95% CI, 0.735–0.0.763) in VISN 9. Using the median rate of exacerbation during the baseline period as the referent, 9 VISNs had lower adjusted rate ratios and 12 VISNs had higher adjusted rate ratios in the follow-up period. Geographic variation in the VA VISN system supports evidence that the medical care system including provider factors, and less so patient factors, affect COPD exacerbations. Understanding the reasons underlying this variation in COPD exacerbation rates may lead to improvements in future care and outcomes.

Use of Spirometry in the Diagnosis of COPD: A Qualitative Study in Primary Care

Abstract Guidelines that recommend spirometry to confirm airflow obstruction among patients with suspected COPD are not routinely followed. We conducted a qualitative study to identify attitudes and barriers of primary care physicians to performing spirometry for patients with possible COPD. We conducted four focus groups, each with three primary care physicians (PCPs) who practice in an urban, academic medical center. In general, PCPs believed that spirometry was not necessary to confirm the diagnosis of COPD. Compared to other co-morbid conditions, in a patient with a diagnosis of COPD without self-reported symptoms, COPD was not a priority during a clinic visit. This was in part due to the belief that there was lack of evidence that medication used in COPD lead to improved outcomes and that there was no point of care measure for COPD compared to other co-morbid conditions such as diabetes mellitus or hypertension. Health system barriers specific to spirometry use was not identified. In conclusion, in our sample of PCPs, there was skepticism that spirometry is warranted to diagnose and manage COPD. Availability of spirometry was not a perceived barrier. Our results explain, in part, why previous interventions to improve access to spirometry and diagnosis of COPD in primary care settings have been difficult to conduct and/or have had marginal success. Our findings strongly suggest that a first step toward increasing the use of spirometry among primary care physicians is to have them believe in its utility in the diagnosis of COPD.

Use of spirometry in the diagnosis of chronic obstructive pulmonary disease and efforts to improve quality of care.

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation that is not fully reversible. In a patient presenting with respiratory symptoms and risk factors, the recommendation is to perform spirometry to determine the presence of airflow obstruction. However, only about a third of patients with a diagnosis of COPD have spirometry along with their diagnosis, although studies have shown that history and physical examination alone are neither sensitive nor specific for diagnosing COPD. Thus, in current practice, many health care providers continue to diagnose and manage COPD without an accurate diagnosis and assessment of severity based on spirometry. This can contribute to inconsistent care and outcomes, as evidenced by findings of variation in spirometry use and acute exacerbation rates of COPD across geographic regions. As there is increasing evidence that pharmacotherapy for COPD has associated risks, including poor cardiovascular outcomes and pneumonia, it is pertinent to obtain an accurate diagnosis to determine appropriate risk-benefit ratios. Previous studies have shown that spirometry has an impact on COPD management; however, there seem to be barriers to the use of spirometry at the patient, provider, and health system level. Innovative quality improvement approaches, such as the application of the various components of the Chronic Care Model, could improve spirometry use in COPD. Only with accurate diagnosis can appropriate management and evidence-based treatment strategies be applied in practice. Therefore, it is important that we continue efforts to increase the use of spirometry in the diagnosis of COPD.

Confirmatory spirometry for adults hospitalized with a diagnosis of asthma or chronic obstructive pulmonary disease exacerbation

BackgroundObjective measurement of airflow obstruction by spirometry is an essential part of the diagnosis of asthma or COPD. During exacerbations, the feasibility and utility of spirometry to confirm the diagnosis of asthma or chronic obstructive pulmonary disease (COPD) are unclear. Addressing these gaps in knowledge may help define the need for confirmatory testing in clinical care and quality improvement efforts. This study was designed to determine the feasibility of spirometry and to determine its utility to confirm the diagnosis in patients hospitalized with a physician diagnosis of asthma or COPD exacerbation.MethodsMulti-center study of four academic healthcare institutions. Spirometry was performed in 113 adults admitted to general medicine wards with a physician diagnosis of asthma or COPD exacerbation. Two board-certified pulmonologists evaluated the spirometry tracings to determine the proportion of patients able to produce adequate quality spirometry data. Findings were interpreted to evaluate the utility of spirometry to confirm the presence of obstructive lung disease, according to the 2005 European Respiratory Society/American Thoracic Society recommendations.ResultsThere was an almost perfect agreement for acceptability (κ = 0.92) and reproducibility (κ =0.93) of spirometry tracings. Three-quarters (73%) of the tests were interpreted by both pulmonologists as being of adequate quality. Of these adequate quality tests, 22% did not present objective evidence of obstructive lung disease. Obese patients (BMI ≥30 kg/m2) were more likely to produce spirometry tracings with no evidence of obstructive lung disease, compared to non-obese patients (33% vs. 8%, p = 0.007).ConclusionsAdequate quality spirometry can be obtained in most hospitalized adults with a physician diagnosis of asthma or COPD exacerbation. Confirmatory spirometry could be a useful tool to help reduce overdiagnosis of obstructive lung disease, especially among obese patients.