The association of weight with the detection of airflow obstruction and inhaled treatment among patients with a clinical diagnosis of COPD.

BACKGROUND: Most patients with a clinical diagnosis of COPD have not had spirometry to confirm airflow obstruction (AFO). Overweight and obese patients report more dyspnea than normal weight patients, which may be falsely attributed to AFO. We sought to determine whether overweight and obese patients who received a clinical diagnosis of COPD were more likely to receive a misdiagnosis (ie, lack of AFO on spirometry) and be subsequently treated with inhaled medications. METHODS: The cohort comprised US veterans with COPD (International Classification of Diseases, 9th Revision, code; inhaled medication use; or both) and spirometry measurements from one of three Pacific Northwest Veterans Administration Medical Centers. The measured exposures were overweight and obesity (defined by BMI categories). Outcomes were (1) AFO on spirometry and (2) escalation or deescalation of inhaled therapies from 3 months before spirometry to 9 to 12 months after spirometry. We used multivariable logistic regression with calculation of adjusted proportions for all analyses. RESULTS: Fifty-two percent of 5,493 veterans who had received a clinical diagnosis of COPD had AFO. The adjusted proportion of patients with AFO decreased as BMI increased (P < .01 for trend). Among patients without AFO, those who were overweight and obese were less likely to remain off medications or to have therapy deescalated (adjusted proportions: normal weight, 0.69 [95% CI, 0.64-0.73]; overweight, 0.62 [95% CI, 0.58-0.65; P = .014]; obese, 0.60 [95% CI, 0.57-0.63; P = .001]). CONCLUSIONS: Overweight and obese patients are more likely to be given a misdiagnosis of COPD and not have their inhaled medications deescalated after spirometry demonstrated no AFO. Providers may be missing potential opportunities to recognize and treat other causes of dyspnea in these patients.

Combination antihypertensive therapy among patients with COPD.

BACKGROUND: COPD and hypertension both increase the risk of congestive heart failure (CHF). Current clinical trials do not inform the selection of combination antihypertensive therapy among patients with COPD. We performed a comparative effectiveness study to investigate whether choice of dual agent antihypertensive therapy is associated with risk of hospitalization for CHF among patients with these two conditions. METHODS: We identified a cohort of 7,104 patients with COPD and hypertension receiving care within Veterans Administration hospitals between January 2001 and December 2006, with follow-up through April 2009. We included only patients prescribed two antihypertensive medications. We used Cox proportional hazard models for statistical analysis. RESULTS: Compared with ß-blockers plus an angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker, patients prescribed a thiazide diuretic plus a ß-blocker (adjusted hazard ratio [HR], 0.49; 95% CI, 0.32-0.75), a thiazide plus an angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker (adjusted HR, 0.50; 95% CI, 0.35-0.71), and a thiazide plus a calcium channel blocker (adjusted HR, 0.55; 95% CI, 0.35-0.88) had a significantly lower risk of hospitalization for CHF. After stratification by history of CHF, we found that this association was isolated to patients without a history of CHF. Adjustment for patient characteristics and comorbidities had a small effect on risk of hospitalization. Choice of antihypertensive medication combination had no significant association with risk of COPD exacerbation. CONCLUSIONS: Among patients with comorbid hypertension and COPD requiring two antihypertensive agents, combination therapy that includes a thiazide diuretic was associated with a significantly lower risk of hospitalization for CHF among patients without a history of CHF.

Missing potential opportunities to reduce repeat COPD exacerbations.

INTRODUCTION: Long-acting beta-agonists (LABA) and/or inhaled corticosteroids (ICS) have been shown to reduce COPD exacerbation risk. Using data from a large integrated health-care system, we sought to examine whether these medication classes were initiated after an exacerbation of COPD. METHODS: We identified patients who experienced an inpatient or outpatient COPD exacerbation within the Veterans Affairs Integrated Service Network (VISN)-20. We assessed the addition of a new inhaled therapy (an ICS, LABA or both) within 180 days after the exacerbation. We assessed independent predictors of adding treatment using logistic regression. RESULTS: We identified 45,780 patients with COPD, of whom 2,760 patients experienced an exacerbation of COPD. Of these individuals, 2,570 (93.1 %) were on either none or only one long-acting medication studied (LABA or ICS). In the subsequent 180-day period after their exacerbation, only 875 (34.1 %) patients had at least one of these additional therapies dispensed from a VA pharmacy. Among patients who were treated in the outpatient setting, older age [OR 0.98/year, 95 % CI (0.97-0.99)], current tobacco use [OR 0.74, 95 % CI (0.60-0.90)], greater use of ipratropium bromide [OR 0.97/canister, 95 % CI (0.96-0.98)], prior COPD exacerbation [OR 0.55, 95 % CI (0.46-0.67)], depression [OR 0.77, 95 % CI (0.61-0.98)], CHF [OR 0.74, 95 % CI (0.57-0.97)], and diabetes (OR 0.77 (0.60-0.99)] were associated with lower odds of additional therapy. Patients who were treated in the hospital had similar associated predictors. CONCLUSION: Among patients treated for an exacerbation of COPD, we found relatively few were subsequently prescribed inhaled therapies known to reduce exacerbations.

Predictors of adherence to inhaled medications among Veterans with COPD.

BACKGROUND: Factors contributing to medication nonadherence among patients with chronic obstructive pulmonary disease (COPD) are poorly understood. OBJECTIVES: To identify patient characteristics that are predictive of adherence to inhaled medications for COPD and, for patients on multiple inhalers, to assess whether adherence to one medication class was associated with adherence to other medication classes. DESIGN: Cohort study using data from Veteran Affairs (VA) electronic databases. PARTICIPANTS: This study included 2,730 patients who underwent pulmonary function testing between 2003 and 2007 at VA facilities in the Northwestern United States, and who met criteria for COPD. MAIN MEASURES: We used pharmacy records to estimate adherence to inhaled corticosteroids (ICS), ipratropium bromide (IP), and long-acting beta-agonists (LABA) over two consecutive six month periods. We defined patients as adherent if they had refilled medications to have 80 % of drug available over the time period. We also collected information on their demographics, behavioral habits, COPD severity, and comorbidities. KEY RESULTS: Adherence to medications was poor, with 19.8 % adherent to ICS, 30.6 % adherent to LABA, and 25.6 % adherent to IP. Predictors of adherence to inhaled therapies were highly variable and dependent on the medication being examined. In adjusted analysis, being adherent to a medication at baseline was the strongest predictor of future adherence to that same medication [(Odds ratio, 95 % confidence interval) ICS: 4.78 (3.21-7.11); LABA: 6.56 (3.89-11.04); IP: 13.96 (9.88-19.72)], [corrected] but did not reliably predict adherence to other classes of medications. [corrected]. CONCLUSIONS: Among patients with COPD, past adherence to one class of inhaled medication strongly predicted future adherence to the same class of medication, but only weakly predicted adherence to other classes of medication.

Adherence to long-acting inhaled therapies among patients with chronic obstructive pulmonary disease (COPD).

BACKGROUND: Long-acting inhaled medications are an important component of the treatment of patients with chronic obstructive pulmonary disease (COPD), yet few studies have examined the determinants of medication adherence among this patient population. OBJECTIVE: We sought to identify factors associated with adherence to long-acting beta-agonists (LABA) and inhaled corticosteroids (ICS) among patients with COPD. METHODS: We performed secondary analysis of baseline data collected in a randomized trial of 376 Veterans with spirometrically confirmed COPD. We used electronic pharmacy records to assess adherence, defined as a medication possession ratio of ≥0.80. We investigated the following exposures: patient characteristics, disease severity, medication regimen complexity, health behaviors, confidence in self-management, and perceptions of provider skill. We performed multivariable logistic regression, clustered by provider, to estimate associations. RESULTS: Of the 167 patients prescribed LABA, 54% (n = 90) were adherent to therapy while only 40% (n = 74) of 184 the patients prescribed ICS were adherent. Higher adherence to LABA and ICS was associated with patient perception of their provider as being an "expert" in diagnosing and managing lung disease [For LABA: OR = 21.70 (95% CI 6.79, 69.37); For ICS OR = 7.93 (95% CI 1.71, 36.67)]. Factors associated with adherence to LABA, but not ICS, included: age, education, race, COPD severity, smoking status, and confidence in self-management. CONCLUSIONS: Adherence to long-acting inhaled medications among patients with COPD is poor, and determinants of adherence likely differ by medication class. Patient perception of clinician expertise in lung disease was the factor most highly associated with adherence to long-acting therapies.