ABSTRACT
Background: Little is known about the actual treatment of patients with chronic obstructive pulmonary disease (COPD), either in the inpatient or outpatient settings. We hypothesized that there are substantial opportunities for improvement in adherence with current guidelines and recommendations. Methods: We reviewed the medical records of all patients hospitalized with acute exacerbation of COPD between January 2005 and December 2006 at 5 New York City hospitals. Results: There were 1285 unique patients with 1653 hospitalizations. Of these 1653, 83% were for patients with a prior history of COPD and 368 (22%) represented repeat admissions during our study period. The majority were treated during their hospitalization with a combination of systemic steroids (85%), bronchodilators (94%) and antibiotics (80%). There were 59 deaths (3.6%). Smoking cessation counseling was offered to 48% of active smokers. Influenza and pneumococcal vaccines were administered to half of eligible patients. On discharge, only 46.0% were prescribed maintenance bronchodilators and 24% were not prescribed any inhaled therapy. Even in the 226 unique patients (17.6%) readmitted at least once during course of the study, on discharge only 44.7% were prescribed maintenance bronchodilators and 23% were not prescribed any regular inhaled therapy. Conclusions: Patients hospitalized with acute exacerbation of COPD generally receive adequate hospital care, but there may be opportunities to improve care pharmacologically and with smoking cessation counseling and vaccination during and after hospitalization.
| ABBREVIATIONS | ||
| ACCP | = | American College of Chest Physicians |
| ACP-ASIM | = | American College of Physicians-American Society of Internal Medicine |
| CDC | = | Center for Disease Control |
| COPD | = | Chronic Obstructive Pulmonary Disease |
| GOLD | = | Global Initiative for Obstructive Lung Disease |
| ICD-9 | = | International Classification of Diseases, 9th Revision |
| IQR | = | Interquartile Range |
| LOS | = | Length of Stay |
| SD | = | Standard Deviation |
| SFC | = | Salmeterol and Fluticasone combination |
INTRODUCTION
Chronic obstructive pulmonary disease (COPD) is a common but often unrecognized and under diagnosed disease that affects millions of individuals in the United States. With an estimated prevalence of 16% in the U.S., COPD is currently the fourth leading cause of death in this country, and overall morbidity and mortality from the disease continues to rise, even as smoking rates have leveled off somewhat (Citation1–4). Annually, COPD accounts for 16 million office visits, 500,000 hospitalizations, 110,000 deaths and over $18 billion in direct health care costs (Citation5).
For many years, there had been a degree of therapeutic nihilism regarding treatment of COPD, as only supplemental oxygen for patients with hypoxemia had been shown to confer a survival benefit (Citation1, Citation6, Citation7). However, in the past few years there has been accumulating evidence of interventions and treatment options which appear to have substantial impact on lung function, quality of life, and even mortality. Such interventions include smoking cessation, use of long-acting bronchodilators, use of inhaled steroids, influenza vaccination, and for select patients, lung volume reduction surgery (Citation6–19).
In view of these developments, numerous professional societies have issued guidelines regarding the evaluation and treatment of patients with COPD (Citation20–22). In particular, the GOLD guidelines make specific recommendations regarding inpatient opportunities for reduction and/or prevention of future exacerbations through smoking cessation, vaccination, and consideration of pharmacotherapy such as long-acting beta-agonists, inhaled glucocorticoids and other inhaled therapies (Citation22). It is unclear to what extent these guidelines are followed.
Little is known about the actual treatment of patients with COPD, either in the inpatient or outpatient settings, although published studies suggest that not enough patients receive recommended care (Citation23, 24). In one chart review of 169 COPD patients, only 58% received “recommended care”(Citation24). A large retrospective cohort study which reviewed claims and discharge data from nearly 70,000 patients hospitalized at 360 different hospitals for an acute exacerbation of COPD suggested that medications were underused, overused and misused (Citation25). However, the study was somewhat limited by its methodology in its ability to examine care in detail. To further explore the hypothesis that there is room for improvement in adherence to guidelines for management of patients with COPD, we undertook a chart review at several urban hospitals.
METHODS
We performed a retrospective cohort study by reviewing the medical records of all patients hospitalized with an acute exacerbation of COPD between January 2005 and December 2006 at five New York City hospitals in the New York-Presbyterian Healthcare System, in order to provide a balanced geographic and demographic sample. All charts of patients discharged from the hospital with a primary discharge diagnosis of COPD were screened, as indicated by ICD9 codes of COPD: Obstructive chronic bronchitis without exacerbation 491.20, Obstructive chronic bronchitis with acute exacerbation 491.21, Obstructive chronic bronchitis with acute bronchitis 491.22, Emphysema with Emphysematous Bleb 492.00, Emphysema – Other 492.80, Chronic obstructive asthma 493.20, Chronic obstructive asthma with acute exacerbation 493.22, and Chronic airway obstruction, not elsewhere classified 496. Of these charts, those that lacked physician documentation of acute exacerbation of COPD were excluded. The study was approved by the Institutional Review Boards at each of the 5 hospital sites.
On a monthly basis, data was extracted directly from inpatient records by one clinician for all sites. Information collected included age, gender, race/ethnicity, insurance status, admission source (emergency room, transfer from other hospital, etc.), prior pulmonary function testing results, symptoms on admission, admission medications (as listed in the admission notes), smoking status, smoking cessation counseling, therapy during hospitalization, vaccination status and administration, as well as discharge medication and other therapy (as listed in the discharge notes and orders). Following data collection, the data was entered into a database which was stripped completely of unique identifiers. The data set was reviewed on a routine basis to allow for data cleaning and completeness of data collection. Those hospitalizations where the patient left the hospital prematurely against medical advice were excluded from analysis.
Continuous variables were summarized by mean ± SD or median (interquartile range [IQR]). Categorical variables were summarized by frequency (percentage) and compared using χ2 tests or Fisher's exact tests. p-values less than 0.05 were considered statistically significant. Statistical analyses were performed using SAS version 9.1 (SAS Institute, Cary, NC).
RESULTS
Demographics
There were 1,817 hospital admissions recorded with diagnosis code of COPD in the study period and all of these charts were reviewed. Eighty-eight were excluded for incomplete demographic data, being a transfer from an outside hospital or admission note for acute COPD exacerbation. Twenty-five hospitalizations resulted in the patient leaving against medical advice and were also excluded. Data from 1,285 unique patients with 1,653 hospitalizations were analyzed. The mean age of the cohort was 72.2 years (). There was a slight female predominance (55.5%). The majority of patients were Caucasian (51.7%); however, there were sizable proportions of African Americans (21.8%) and Hispanics (18.2%). Most patients had a prior history of COPD (83.2%) and were admitted via the emergency department (96.9%) with dyspnea (90.6%) and cough (59.0%). Fifty-nine admissions (3.6%) resulted in in-hospital death. Co-morbid conditions were common in this cohort (data not shown). Fifty-three percent had at least one cardiovascular co-morbid condition among congestive heart failure, diabetes, coronary artery disease and peripheral vascular disease. Seventeen percent had cancer and another 17% had 6 or more reported co-morbid conditions.
Table 1. Characteristics of the cohort
Hospital care
The majority of patients were treated with a combination of systemic steroids (85.2%), bronchodilators (93.8%) and antibiotics (79.7%). Arterial blood gas or pulse oximetry assessment was performed in 75.0% of patients (). Spirometry and sputum cultures were obtained in 4.1% and 20.0%, respectively.
Table 2. Hospital evaluation and management
Smoking status was assessed in 94.7% of patients with 33.0% identified as active smokers (). Smoking cessation counseling was provided to only 48.1% of active smokers. There were 539 (32.6%) hospitalizations during an influenza vaccination season which was defined in this study as October 15th to January 31st (). Of these hospitalizations, influenza vaccination status was assessed in 79.2%, of which 48.2% were eligible for vaccination. Of those eligible, 51.0% were documented to have influenza vaccination provided prior to discharge. Pneumococcal vaccination status was assessed in 78% of patients with 46.3% identified as being eligible for vaccination (). Of those eligible, documentation of vaccination during the hospitalization was evident in 50.2%.
Outpatient medications
On admission, 28.4% were on systemic steroids, 30.0% were on inhaled steroids, and 30.7% were on oxygen or non-invasive ventilation (). At discharge, 68.1% were prescribed systemic steroids, 41.3% were prescribed inhaled steroids, and 36.7% were prescribed oxygen or non-invasive ventilation. The percentage of patients on combination salmeterol and fluticasone (SF) increased from 28.5% on admission to 35.2% at discharge. Tiotropium usage increased from 15.6% to 26.1%. Use of any long-acting bronchodilator therapy increased from 35.4% to 46.2%. The percentage on no regular inhaled therapy decreased from 30.9% on admission to 24.3% on discharge.
Table 3. Admission and discharge medications
Readmissions
Of the 1285 unique patients admitted during the course of the study, 226 patients (17.6%) were admitted more than once. These multiply admitted patients were of similar age and gender as those admitted only once. When comparing their first admissions captured in the study period, patients with multiple subsequent admissions were more likely than patients with single admissions to be prescribed systemic steroids, long-acting and short-acting bronchodilators, and oxygen or non-invasive ventilation prior to admission (). Patients with multiple admissions were more likely to be prescribed systemic steroids, short-acting bronchodilators and oxygen or non-invasive ventilation upon discharge (). Patients with multiple admissions have rates of active smoking similar to patients with single admissions (33.5% vs. 37.0% respectively, p = 0.32) and similar rates of smoking cessation counseling (48.2% vs. 45.0% respectively) (). Significantly more patients with multiple admissions had previously received pneumococcal vaccinations (59.6% vs. 48.1%, p = 0.007). Rates of pre-discharge influenza vaccination and pneumococcal vaccination were similar in both groups.
DISCUSSION
This study is the largest thus far utilizing medical record review to evaluate the care of patients admitted for acute exacerbations of COPD. Given the number of patients in this study, the variety of hospitals from which they were drawn, and the demographic characteristics of the population, we feel that these results are representative and are likely to apply to large numbers of patients with COPD in urban areas of the United States. In the inpatient setting, we found that treatment of COPD exacerbations was largely in accord with published guidelines. However, we found that there may be opportunities for interventions, including aggressive efforts at smoking cessation, vaccination against influenza and pneumococcal pneumonia, and improved outpatient provision of bronchodilator and anti-inflammatory therapy, which could have a positive impact on care.
There is a well-known gap between clinical evidence for best practices, the promulgation of guidelines, and practice patterns. One retrospective review of outpatient medical records of 164 COPD patients revealed a very low adherence (58%) to quality care measures based on published guidelines (Citation24). Barriers that can impair adherence to practice guidelines range from lack of awareness and familiarity with the evidence to lack of agreement to problems overcoming practice inertia (Citation26). Several surveys demonstrate that there are major knowledge gaps and deficiencies in the care of patients with COPD among primary care providers and specialists (Citation27, 28). However, implementation of existing evidence based practices can lead to substantial clinical benefit (Citation29).
Exacerbations of COPD are associated with substantial morbidity and mortality. As a consequence, effective therapies that can reduce the likelihood of an exacerbation can have substantial benefit. After suffering COPD exacerbations, patients have decreases in their functional status that last well beyond discharge (Citation30). A significant number of patients have incomplete recovery after a COPD exacerbation (Citation31). Patients with frequent exacerbations have worse quality of life and faster rates of decline in their pulmonary function (Citation32, 33).
Furthermore, there is substantial mortality associated with COPD exacerbations with estimated inpatient mortality of 2.5–7.4% for the average patient admitted for an acute exacerbation of COPD to 24–30% for selected patients requiring admission to the intensive care unit (Citation34–38).
A joint panel from the American College of Physicians-American Society of Internal Medicine (ACP-ASIM) and the American College of Chest Physicians (ACCP) reviewed the evidence on the evaluation and management of COPD (Citation5). They found evidence for the use of chest radiography, arterial blood gas sampling, bronchodilators, corticosteroids, and noninvasive positive-pressure ventilation for patients with respiratory failure. Most guidelines recommend inhaled bronchodilators, antibiotics and a short course of systemic corticosteroids for patients hospitalized for an acute exacerbation of COPD (Citation22). In our study most patients were treated with inhaled bronchodilators (92.5%), systemic steroids (83.7%) and antibiotics (79.8%), which was generally close to these guideline recommendations. This level of adherence to guidelines is similar to the findings of previous studies of inpatient management of COPD exacerbations (Citation23, Citation25).
However, there were opportunities for improvement during the course of inpatient care. Out of the 94.7% of patients in whom smoking status was assessed, 33% were active smokers. Smoking prevention and cessation are key components in the prevention and management of COPD (Citation5, Citation20, Citation22). Data from the Lung Health Study show that smoking cessation is the only intervention thus far shown to slow the decline in lung function in patients with COPD(Citation39). Furthermore, smoking cessation has been shown in randomized clinical trials to reduce all cause mortality (Citation40). In our study only 48.1% of the active smokers were provided with smoking cessation counseling.
This rate of inpatient smoking cessation counseling is similar to that described at other hospitals in previously published studies (Citation41, 42). It is important to point out that there may be a difference between whether counseling has been provided, or provided and documented. Even with this potential discrepancy, the investigators believe that opportunities for improved compliance exist, especially recognizing that patients with multiple admissions had rates of active smoking similar to patients with single admissions.
Influenza and pneumococcal vaccination rates in the population we studied were also low. In the current study, most patients had their vaccination status assessed during hospitalization. But of the 46% eligible for the pneumococcal vaccine and 48% eligible for the influenza vaccine, only 50% were actually documented as having been given the vaccine prior to discharge. Similarly, vaccination rates by other studies have also been low, ranging from 17–67% of patients with chronic lung disease (Citation43–45). Although the utility of pneumococcal vaccination is still a matter of some debate (Citation46), both influenza and pneumococcal vaccination is currently recommended by the American College of Physicians, the American College of Chest Physicians, and the CDC's Advisory Council on Immunization Practices. Furthermore, inpatient administration of these vaccines has been shown to improve vaccination uptake among high risk populations, particularly those who are frequently admitted to the hospital (Citation47).
Since we collected data on medications used by patients on admission to hospital, we were able to assess to some degree outpatient treatment of COPD, and here too we detected potential opportunities for improvement in care. In recent years, considerable evidence from randomized, controlled trials has accumulated to support the use of long-acting bronchodilators and inhaled steroids for certain patients with COPD. Several studies including TORCH and UPLIFT have shown a significant benefit of inhaled corticosteroids and bronchodilators in reduction of COPD exacerbations and related hospitalizations (Citation11, Citation48). The GOLD guidelines reflect this: long-acting bronchodilators are recommended in patients with at least moderate COPD (GOLD class II) and inhaled corticosteroids are indicated for patients with at least GOLD class III (FEV1/FVC <70% and FEV1 between 30% and 50% of predicted) COPD and a history of exacerbations (Citation22).
In this study, the diagnosis of COPD is based upon coded discharge diagnoses which may not be accurate. The study sample may be missing a group of patients that were admitted for AECOPD that had not received a COPD diagnostic code, such as that for respiratory failure. Through thorough chart review we are confident that those hospitalizations included in the study were indeed for AECOPD, however, it is possible that some cases were missed. This methodology has been used in other major studies and has been found to be valid (Citation49). We did not have the available data to classify patients into GOLD stages. The benefit of inhaled therapy with long-acting beta-agonist, anticholinergics and steroids in reducing an acute exacerbation of COPD has been shown only for patients with moderate to severe COPD.
Our study design precluded obtaining complete pulmonary function data from most of patients we reviewed. Less than 5% of the inpatient charts had details of prior spirometry data. Of the minimal data available, the median percent-predicted FEV1 was 39.5% (IQR 26–59), and the mean FEV1/FVC ratio was 55 ± 18%. Still, nearly 30% of admitted patients were on supplemental oxygen or noninvasive ventilation at the time of admission and 28% were on systemic steroids at the time of admission suggesting significant disease. In addition almost 20% had multiple hospitalizations during course of study and of these 45.9% were receiving outpatient oxygen or non-invasive ventilation at the time of admission suggesting that a substantial portion of patients had at least moderate to severe COPD and may have been undertreated according to widely promulgated guidelines.
Thus, despite the lack of information regarding spirometry-defined severity of the patients in this cohort, we believe it is likely that these patients in our cohort who required hospital admission, are frequently readmitted and often on supplemental oxygen, would warrant some form of maintenance bronchodilator and/or inhaled steroid therapy.
Since this is an inpatient chart review, there are some potential limitations in the report of pre-hospital therapy. It is possible that there was underreporting of as needed short-acting bronchodilator use that may lead to an underestimation of overall use any sort of inhaled therapy. It is further unclear what proportion of the admission medications and therapies such as oxygen, non-invasive ventilation, systemic steroids and antibiotics were actually chronic maintenance therapy vs. a reflection of some outpatient escalation of therapy in response to the current exacerbation, as these were recorded as being the list the patient was on upon admission.
There was an increase in the usage of maintenance bronchodilators and inhaled steroids on discharge (), but the percentage of people discharged on these medications is still less than optimal. Inhaled long-acting anticholinergic usage increased from 15.6% on admission to only 26.1% on discharge. Inhaled steroid usage, mainly as salmeterol and fluticasone combination (SF) therapy, increased from 28.5% on admission only to 35.2% at discharge, though this potentially was influenced by the large number of patients discharged on systemic steroids. Still, use of any inhaled therapy increased from 69.1% to only 75.7%, meaning 24% were discharged without any regular inhaled therapy.
Table 4. Management patterns in Single and Multiple Admissions*
In patients with multiple admissions during the course of the study (17.6% of the total population studied), 19.5% were not being treated with maintenance bronchodilators and 65.5% were not being treated with inhaled corticosteroids. Notably, 23% of the time these patients were discharged without any regular inhaled medications. The study design did not permit evaluation of the question of whether the apparent undertreatment was due to suboptimal follow-up, under or mis-prescribing or patient compliance.
The subgroup of patients who were multiply admitted during our study period may represent a group of patients with frequent exacerbations. In these patients, despite prior hospitalization for COPD exacerbation, they have similar rates of active smoking as well as smoking cessation counseling. Theoretically, these are the patients in whom aggressive in-hospital smoking cessation counseling might be particularly beneficial. The finding that more patients with multiple admissions had previously received pneumococcal vaccination, may reflect that higher frequency of exposure to medical care and opportunities to get vaccinated despite similar rates of pre-discharge vaccination.
One strength of our study is the large size of more than 1,653 hospitalizations whose medical records were reviewed extensively by a clinician. Our specific focus on admission and discharge medication regimens allow us to evaluate care outside of the index hospitalization as well. On the other hand, our data were collected through a review of medical records and as such, poor documentation of counseling items like smoking cessation counseling could be an important factor affecting the results.
In addition, review of medical records may underestimate prior use of certain inhaled medications that were prescribed and stopped because no clear benefit was noted by the patient, or they were just too expensive, and may underestimate the percent using as needed short-acting bronchodilators. Furthermore, some patients on discharge may tell a prescribing physician that they have medications and nebulizers at home, and therefore they are not represcribed and potentially omitted from the discharge record. Still, underutilization of COPD maintenance therapy is a well-recognized problem (Citation50).
The design of this study as an inpatient chart review precludes the ability to capture events that occur outside of the hospital, including deaths, and as such, our ability to assess the effects of in-hospital management on total mortality is limited. The rate of in-hospital mortality in this study 3.5% is relatively comparable to prior observations (Citation49).
In conclusion, we found that most patients hospitalized for an acute exacerbation of COPD were treated in accordance with published guidelines. However, by taking advantage of the hospitalization to counsel smoking cessation, provide influenza and pneumococcal vaccination and improve outpatient provision of inhaled bronchodilator and anti-inflammatory therapy there may be further opportunities to improve care.
Declaration of interest
Drs. Yip, Yuen, Lazar, Regan, Taylor, Karbowitz, Stumacher, Schluger, and Ms. Brinson report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
ACKNOWLEDGEMENTS
Funding was received by the United Hospital Fund 051013S. Dr. George has received research grants from Orthobiotech, Parexel, Pfizer and GlaxoSmithKline. Dr. Thomashow has received honoraria from Boehringer Ingelheim, Pfizer, Glaxo-SmithKline, and Astra Zeneca.
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