Abstract 7: Appropriateness of Percutaneous Coronary Interventions in Washington State

Background. The use of percutaneous coronary intervention (PCI) has increased dramatically in the past decade despite uncertainty regarding the appropriateness of these procedures. Methods. Within the Clinical Outcomes Assessment Program (COAP), a quality-improvement initiative that captures all revascularization procedures performed in Washington State, we assessed the appropriateness of PCI performed between June 2009 and September 2010 in accordance with published Appropriate Use Criteria. We report the appropriateness of PCI stratified by acute (acute myocardial infarction or unstable angina with high-risk features) or non-acute (stable angina) coronary presentation.

Results. Of 12,528 PCI performed during the study period, we successfully mapped the PCI indication to the Appropriate Use Criteria in 9,025 (72%) of cases. Of the 3,521 PCI not classified, common failures to map to the criteria included acute PCI of multiple lesions without evidence of shock (n=517, 14.7%), unstable angina without high-risk features (n=918, 26.1%), or non-acute PCI without preprocedural non-invasive stress results (n=2,049, 58.2%). Of mapped PCI, 7,031 (77.9%) were for acute indications with 6,921 (98.4%) rated as “appropriate”, 40 (0.6%) as “uncertain”, and 70 (1.0%) as “inappropriate”. Of 1,987 non-acute coronary presentations, 788 (39.7%) were rated as appropriate, 812 (40.9%) as uncertain, and 387 (19.5%) as inappropriate (Table). Assuming non-acute PCI with missing data on non-invasive stress test were performed in the setting of high-risk non-invasive stress testing, 387 (9.8%) PCI were inappropriate.

Conclusion. In a complete cohort of PCI performed in Washington State, 1.0% of PCI for acute indications and 9.8% of PCI for non-acute indications were classified as inappropriate after assumptions to maximize appropriateness. These findings suggest an opportunity to improve the selection of patients undergoing PCI to maximize anticipated benefit.

TABLE 1

Obesity and COPD: associated symptoms, health-related quality of life, and medication use

BACKGROUND

There is little data about the combined effects of COPD and obesity. We compared dyspnea, health-related quality of life (HRQoL), exacerbations, and inhaled medication use among patients who are overweight and obese to those of normal weight with COPD.

METHODS

We performed secondary data analysis on 364 Veterans with COPD. We categorized subjects by body mass index (BMI). We assessed dyspnea using the Medical Research Council (MRC) dyspnea scale and HRQoL using the St. George's Respiratory Questionnaire. We identified treatment for an exacerbation and inhaled medication use in the past year. We used multiple logistic and linear regression models as appropriate, with adjustment for age, COPD severity, smoking status, and co-morbidities.

RESULTS

The majority of our population was male (n = 355, 98%) and either overweight (n = 115, 32%) or obese (n = 138, 38%). Obese and overweight subjects had better lung function (obese: mean FEV(1) 55.4% ±19.9% predicted, overweight: mean FEV(1) 50.0% ±20.4% predicted) than normal weight subjects (mean FEV(1) 44.2% ±19.4% predicted), yet obese subjects reported increased dyspnea [adjusted OR of MRC score ≥2 = 4.91 (95% CI 1.80, 13.39], poorer HRQoL, and were prescribed more inhaled medications than normal weight subjects. There was no difference in any outcome between overweight and normal weight patients.

CONCLUSIONS

Despite having less severe lung disease, obese patients reported increased dyspnea and poorer HRQoL than normal weight patients. The greater number of inhaled medications prescribed for obese patients may represent overuse. Obese patients with COPD likely need alternative strategies for symptom control in addition to those currently recommended.

Recent hospitalization for non-coronary events and use of preventive medications for coronary artery disease: an observational cohort study

Background

High-quality systems have adopted a comprehensive approach to preventive care instead of diagnosis or procedure driven care. The current emphasis on prescribing medications to prevent complications of coronary artery disease (CAD) at discharge following an acute coronary syndrome (ACS) may exclude high-risk patients who are hospitalized with conditions other than ACS.

Methods

Among a sample of patients with CAD treated at Veterans Affairs medical centers between January, 2005 and November, 2006, we investigated whether recent non-ACS hospitalization was associated with prescriptions of preventive medications as compared with patients recently hospitalized with ACS.

Results

Of 13,211 patients with CAD, 58% received aspirin, 70% β-blocker, 60% angiotensin-converting enzyme inhibitor (ACE-I) or angiotensin II receptor blocker (ARB), and 65% lipid-lowering therapy. Twenty-five percent of eligible patients were receiving all four medications. Having been hospitalized for a non-ACS event in the prior 6 months did not substantially affect the adjusted proportion on preventive medications. In contrast, among patients hospitalized for ACS in the prior 6 months, the adjusted proportion prescribed aspirin was 21% higher (p < 0.001), β-blocker was 14% higher (p < 0.001), ACE-I or ARB was 9% higher (p < 0.001), lipid therapy was 12% higher (p < 0.001), and prescribed all four medications was 18% higher (p < 0.001) than among patients hospitalized for ACS more than 2 years earlier.

Conclusions

Being hospitalized for a non-ACS condition did not appear to influence preventive medication use among patients with CAD and represents a missed opportunity to improve patient care. The same protocols employed to improve use of preventive medications in patients discharged for ACS might be extended to CAD patients discharged for other conditions as well.

Are smoking and alcohol misuse associated with subsequent hospitalizations for ambulatory care sensitive conditions?

Hospitalizations for ambulatory care sensitive conditions (ACSCs) are used to assess quality of care, but studies rarely adjust for health behaviors. This study evaluated whether results of smoking or alcohol screening were associated with hospitalizations for ACSCs. Participants included 33,273 male Veterans Affairs general medicine outpatients who returned mailed surveys. The main outcome was hospitalization with a primary discharge diagnosis for an ACSC in the year following screening. Analyses were adjusted for demographics, comorbidity, and other health behaviors. Current and previous smoking and abstaining from alcohol were associated with significantly increased risk of hospitalization for ACSCs, but alcohol misuse was not. However, severe alcohol misuse was associated with increased risk of hospitalizations with a primary or secondary ACSC discharge diagnosis. When ACSCs are used to evaluate the quality of care, health systems caring for populations with higher rates of smoking or nondrinking could falsely appear to have poorer quality care if alcohol and tobacco use are not considered.

Importance of health system context for evaluating utilization patterns across systems

Measuring health services provided to patients can be difficult when patients see providers across multiple health systems and all visits are rarely captured in a single data source covering all systems where patients receive care. Studies that account for only one system will omit the out-of-system health-care use at the patient level. Combining data across systems and comparing utilization patterns across health systems creates complications for both aggregation and accuracy because data-generating processes (DGPs) tend to vary across systems. We develop a hybrid methodology for aggregation across systems, drawing on the strengths of the DGP in each system, and demonstrate its validity for answering research questions requiring cross-system assessments of health-care utilization. Positive and negative predictive probabilities can be useful to assess the impact of the hybrid methodology. We illustrate these issues comparing public sector (administrative records from the US Department of Veterans Affairs system) and private sector (billing records from the US Medicare system) patient level data to identify primary-care utilization. Understanding the context of a particular health system and its effect on the DGP is important in conducting effective valid evaluations.

Alcohol screening and risk of postoperative complications in male VA patients undergoing major non-cardiac surgery

BACKGROUND

Patients who misuse alcohol are at increased risk for surgical complications. Four weeks of preoperative abstinence decreases the risk of complications, but practical approaches for early preoperative identification of alcohol misuse are needed.

OBJECTIVE

To evaluate whether results of alcohol screening with the Alcohol Use Disorders Identification Test - Consumption (AUDIT-C) questionnaire-up to a year before surgery-were associated with the risk of postoperative complications.

DESIGN

This is a cohort study.

SETTING AND PARTICIPANTS

Male Veterans Affairs (VA) patients were eligible if they had major noncardiac surgery assessed by the VA's Surgical Quality Improvement Program (VASQIP) in fiscal years 2004-2006, and completed the AUDIT-C alcohol screening questionnaire (0-12 points) on a mailed survey within 1 year before surgery.

MAIN OUTCOME MEASURE

One or more postoperative complication(s) within 30 days of surgery based on VASQIP nurse medical record reviews.

RESULTS

Among 9,176 eligible men, 16.3% screened positive for alcohol misuse with AUDIT-C scores ≥ 5, and 7.8% had postoperative complications. Patients with AUDIT-C scores ≥ 5 were at significantly increased risk for postoperative complications, compared to patients who drank less. In analyses adjusted for age, smoking, and days from screening to surgery, the estimated prevalence of postoperative complications increased from 5.6% (95% CI 4.8-6.6%) in patients with AUDIT-C scores 1-4, to 7.9% (6.3-9.7%) in patients with AUDIT-Cs 5-8, 9.7% (6.6-14.1%) in patients with AUDIT-Cs 9-10 and 14.0% (8.9-21.3%) in patients with AUDIT-Cs 11-12. In fully-adjusted analyses that included preoperative covariates potentially in the causal pathway between alcohol misuse and complications, the estimated prevalence of postoperative complications increased significantly from 4.8% (4.1-5.7%) in patients with AUDIT-C scores 1-4, to 6.9% (5.5-8.7%) in patients with AUDIT-Cs 5-8 and 7.5% (5.0-11.3%) among those with AUDIT-Cs 9-10.

CONCLUSIONS

AUDIT-C scores of 5 or more up to a year before surgery were associated with increased postoperative complications.

Use of outpatient care in Veterans Health Administration and Medicare among veterans receiving primary care in community-based and hospital outpatient clinics

OBJECTIVE

To examine differences in use of Veterans Health Administration (VA) and Medicare outpatient services by VA primary care patients.

DATA SOURCES/STUDY SETTING

VA administrative and Medicare claims data from 2001 to 2004.

STUDY DESIGN

Retrospective cohort study of outpatient service use by 8,964 community-based and 6,556 hospital-based VA primary care patients.

PRINCIPAL FINDINGS

A significant proportion of VA patients used Medicare-reimbursed primary care (>30 percent) and specialty care (>60 percent), but not mental health care (3-4 percent). Community-based patients had 17 percent fewer VA primary care visits (p<.001), 9 percent more Medicare-reimbursed visits (p<.001), and 6 percent fewer total visits (p<.05) than hospital-based patients. Community-based patients had 22 percent fewer VA specialty care visits (p<.0001) and 21 percent more Medicare-reimbursed specialty care visits (p<.0001) than hospital-based patients, but no difference in total visits (p=.80).

CONCLUSIONS

Medicare-eligible VA primary care patients followed over 4 consecutive years used significant primary care and specialty care outside of VA. Community-based patients offset decreased VA use with increased service use paid by Medicare, suggesting that increasing access to VA primary care via community clinics may fragment veteran care in unintended ways. Coordination of care between VA and non-VA providers and health care systems is essential to improve the quality and continuity of care.

Patient-clinician communication: associations with important health outcomes among veterans with COPD

BACKGROUND

High quality patient-clinician communication is widely advocated, but little is known about which health outcomes are associated with communication for patients with COPD.

METHODS

Using a cross-sectional study of 342 veterans enrolled in a randomized controlled trial, we evaluated the association of communication, measured with the quality of communication (QOC) instrument, with subject-reported quality of clinician care, breathing problem confidence, and general self-rated health. We measured these associations using general estimating equations and adjusted odds ratios (OR) of patient-reported outcomes associated with one-point changes in QOC scores.

RESULTS

Nearly one-half of the subjects reported receiving the best imaginable care (47%), whereas fewer reported being confident with their breathing problems all the time (29%) or in very good or excellent health (15%). General communication was associated with best-imagined quality of care (OR, 4.29; 95% CI, 2.84-6.48; P < .001) and confidence in dealing with breathing problems all the time (OR, 1.74; 95% CI, 1.34-2.25; P < .001) but not general self-rated health (OR, 1.19; 95% CI, 0.92-1.55; P = .19). Specific clinician behaviors with larger associations with higher quality care included listening, caring, and attentiveness. The associations between general communication and quality care increased over time (P for interaction .03).

CONCLUSIONS

Communication between patients and clinicians is associated with quality of care and confidence in dealing with breathing problems, and this association may change over time. Attention to specific communication strategies may lead to improvements in the care of patients with COPD.

Increasing copayments and adherence to diabetes, hypertension, and hyperlipidemic medications

OBJECTIVE

To examine the impact of a medication copayment increase on adherence to diabetes, hypertension, and hyperlipidemic medications.

STUDY DESIGN

Retrospective pre-post observational study.

METHODS

This study compared medication adherence at 4 Veterans Affairs medical centers between veterans who were exempt from copayments and propensity-matched veterans who were not exempt. The diabetes sample included 1069 exempt veterans and 1069 nonexempt veterans, the hypertension sample included 3545 exempt veterans and 3545 nonexempt veterans, and the sample of veterans taking statins included 2029 exempt veterans and 2029 nonexempt veterans. The main outcome measure was medication adherence 12 months before and 23 months after the copayment increase. Adherence differences were assessed in a difference-in-difference approach by using generalized estimating equations that controlled for time, copayment exemption, an interaction between time and copayment exemption, and patient demographics, site, and other factors.

RESULTS

Adherence to all medications increased in the short term for all veterans, but then declined in the longer term (February-December 2003). The change in adherence between the preperiod and the postperiod was significantly different for exempt and nonexempt veterans in all 3 cohorts, and nonadherence increased over time for veterans required to pay copayments. The impact of the copayment increase was particularly adverse for veterans with diabetes who were required to pay copayments.

CONCLUSION

A $5 copayment increase (from $2 to $7) adversely impacted medication adherence for veterans subject to copayments taking oral hypoglycemic agents, antihypertensive medications, or statins.

Medication adherence: its importance in cardiovascular outcomes

Medication adherence usually refers to whether patients take their medications as prescribed (eg, twice daily), as well as whether they continue to take a prescribed medication. Medication nonadherence is a growing concern to clinicians, healthcare systems, and other stakeholders (eg, payers) because of mounting evidence that it is prevalent and associated with adverse outcomes and higher costs of care. To date, measurement of patient medication adherence and use of interventions to improve adherence are rare in routine clinical practice. The goals of the present report are to address (1) different methods of measuring adherence, (2) the prevalence of medication nonadherence, (3) the association between nonadherence and outcomes, (4) the reasons for nonadherence, and finally, (5) interventions to improve medication adherence.

Alcohol screening scores and all-cause mortality in male Veterans Affairs patients

OBJECTIVE

Extensive research demonstrates a J- or U-shaped association between in-depth interview measures of alcohol consumption and mortality. Little is known about the relationship between alcohol screening questionnaires and mortality. This study examined the association between scores (ranging from 0 to 12) on the three-item Alcohol Use Disorder Identification Test-Consumption Questionnaire (AUDIT-C) and mortality.

METHOD

This cohort study included male outpatients from seven Veterans Affairs (VA) medical centers who completed the AUDIT-C on mailed surveys (1997-2000; n=34,292) and who were followed for a mean of 2.5 years. Death was ascertained from VA databases.

RESULTS

In analyses adjusted for demographics, a U-shaped relationship was observed between AUDIT-C scores and all-cause mortality. Nondrinkers (AUDIT-C 0) and heavy drinkers (AUDIT-C 8-9 and 10-12) had increased risk of death compared with drinkers who screened negative for alcohol misuse (AUDIT-C 1-3): hazard ratios (HR)=1.41 (95% confidence interval [CI]: 1.29-1.54), 1.32 (1.03-1.69), and 1.47 (1.14-1.91), respectively. This association differed across age groups (p=.003). For men younger than 50 years, AUDIT-C scores 10-12 were associated with increased mortality (HR=2.21, 95% CI: 1.29-3.77), whereas for men age 50 or older, self-reported abstinence (AUDIT-C 0) was associated with increased mortality, compared with drinkers with AUDIT-C scores 1-3: HR formen 50-64=1.45 (1.19-1.77); HR for men 65 or older=1.42 (1.28-1.58).

CONCLUSIONS

A U-shaped association between the AUDIT-C and mortality was observed, with important differences by age group. This is the first study to demonstrate that a clinical scaled screening measure of alcohol use has a similar association with mortality to that observed in epidemiological research with lengthier measures.

The association of inhaled corticosteroid use with serum glucose concentration in a large cohort

BACKGROUND

Inhaled corticosteroids (ICSs) are widely used in the treatment of obstructive lung disease. ICSs have been shown to be systemically absorbed. The association between ICS and serum glucose concentration is unknown.

METHODS

To explore the association of ICS dosing with serum glucose concentration, we used a prospective cohort study of US veterans enrolled in 7 primary care clinics between December 1996 and May 2001 with 1 or more glucose measurements while at least 80% adherent to ICS dosing. The association between ICS dose from pharmacy records standardized to daily triamcinolone equivalents and serum glucose concentration was examined with generalized estimating equations controlling for confounders, including systemic corticosteroid use.

RESULTS

Of the 1698 subjects who met inclusion criteria, 19% had self-reported diabetes. The mean daily dose of ICS in triamcinolone equivalents was 621 microg (standard deviation 555) and 610 microg (standard deviation 553) for subjects with and without diabetes, respectively. After controlling for systemic corticosteroid use and other potential confounders, no association between ICS and serum glucose was found for subjects without diabetes. However, among subjects with self-reported diabetes, every additional 100 microg of ICS dose was associated with an increased glucose concentration of 1.82 mg/dL (P value .007; 95% confidence interval [CI], 0.49-3.15). Subjects prescribed antiglycemic medications had an increase in serum glucose of 2.65 mg/dL (P value .003; 95% CI, 0.88-4.43) for every additional 100 microg ICS dose.

CONCLUSION

Among diabetic patients, ICS use is associated with an increased serum glucose concentration in a dose-response manner.

Alcohol screening scores predict risk of subsequent fractures

The Alcohol Use Disorders Identification Test-Consumption (AUDIT-C; 0-12 points) was included on health surveys in a cohort of 32,622 general medicine outpatients from seven US Department of Veterans Affairs (VA) hospitals. Cox proportional hazards models were used to estimate the risk of fracture (mean follow-up = 1.6 years) by AUDIT-C category. After adjusting for confounders, AUDIT-C scores of 8-9 and 10-12 were associated with significantly increased risks for subsequent fractures, HR (95% CI) = 1.37 (1.03 to 1.83) and 1.79 (1.38 to 2.33) respectively. These results can be used to provide feedback to patients linking their alcohol screening scores to medical outcomes-a critical component of evidence-based brief counseling for alcohol misuse. The study's limitations are noted.

Alcohol screening scores and medication nonadherence

BACKGROUND

Medication nonadherence is common and is associated with adverse outcomes. Alcohol misuse may be a risk factor for nonadherence; however, evidence is limited.

OBJECTIVE

To identify whether alcohol misuse, as identified by a simple screening tool, is associated in a dose-response manner with increased risk for medication nonadherence in veterans attending primary care clinics.

DESIGN

Secondary analysis of cohort data collected prospectively from 1997 to 2000 as part of a randomized, controlled trial.

SETTING

7 Veterans Affairs primary care clinics.

PARTICIPANTS

5473 patients taking a statin, 3468 patients taking oral hypoglycemic agents, and 13 729 patients taking antihypertensive medications.

MEASUREMENTS

Patients completed the Alcohol Use Disorder Identification Test-Consumption (AUDIT-C) questionnaire, a validated 3-question alcohol misuse screening test. Their scores were categorized into nondrinkers; low-level alcohol use; and mild, moderate, and severe alcohol misuse. Medication adherence, defined as having medications available for at least 80% of the observation days, was measured from pharmacy records for either 90 days or 1 year after the alcohol screening date. Logistic regression was used to estimate the predicted proportions of adherent patients in each AUDIT-C group and adjusted for demographic and clinical covariates.

RESULTS

The proportion of patients treated for hypertension and hyperlipidemia who were nonadherent increased with higher AUDIT-C scores. For 1-year adherence to statins, the percentage of adherent patients was lower in the 2 highest alcohol misuse groups (adjusted percentage of adherent patients, 58% [95% CI, 52% to 65%] and 55% [CI, 47% to 63%]) than in the nondrinker group (66% [CI, 64% to 68%]). For 1-year adherence to antihypertensive regimens, the percentage of adherent patients was lower in the 3 highest alcohol misuse groups (adjusted percentage of adherent patients, 61% [CI, 58% to 64%]; 60% [CI, 56% to 63%]; and 56% [CI, 52% to 60%]) than in the nondrinker group (64% [CI, 63% to 65%]). No statistically significant differences were observed for oral hypoglycemics in adjusted analyses.

LIMITATION

This observational study cannot address whether changes in drinking lead to changes in adherence and may not be generalizable to other populations.

CONCLUSION

Alcohol misuse, as measured by a brief screening questionnaire, was associated with increased risk for medication nonadherence.

The association between alcohol consumption and risk of COPD exacerbation in a veteran population

BACKGROUND

Alcohol has been associated with COPD-related mortality but has not yet been demonstrated to be an independent risk factor for COPD exacerbation. Our objective was to evaluate the association between alcohol consumption and the subsequent risk of COPD exacerbation.

METHODS

A prospective cohort study of general medicine outpatients seen at one of seven Veterans Affairs (VA) medical centers who returned health screening questionnaires. Three screening questionnaires, AUDIT-C (0 to 12 points), CAGE (0 to 4 points), and a single item about the frequency of drinking six or more drinks on an occasion (binge drinking), were used to classify alcohol consumption. The main outcome, COPD exacerbation, was based on primary VA discharge diagnosis (International Classification of Diseases, Ninth Revision) or outpatient diagnosis of COPD accompanied by prescriptions for either antibiotics or prednisone within 2 days.

RESULTS

Among the 30,503 patients followed up for a median of 3.35 years, those patients with AUDIT-C scores > or = 6, CAGE scores > or = 2, or who reported binge drinking at least weekly were at an increased risk of COPD exacerbation in age-adjusted analysis. Adjusted hazard ratios were 1.4 (95% confidence interval [CI], 1.1 to 1.7) for AUDIT-C score > or = 6, 1.4 (95% CI, 1.3 to 1.5) for CAGE score > or = 2, and 1.6 (95% CI, 1.2 to 2.2) for those who reported binge drinking daily or almost daily. However, with adjustment for measures of tobacco use, the association between alcohol consumption and increased risk of COPD exacerbation was no longer evident.

CONCLUSIONS

Alcohol consumption, whether quantified by AUDIT-C, CAGE score, or binge drinking, was not associated with an increased risk of COPD exacerbation independent of tobacco use.

Prevalence and trends of insulin resistance, impaired fasting glucose, and diabetes

OBJECTIVE

Our aim was to measure the prevalence and time trends of diabetes, impaired fasting glucose, and insulin resistance in the United States during the periods 1988-1994 and 1999-2002.

MATERIALS AND METHODS

Data were derived from two nationally representative samples of the adult U.S. population collected as part of the National Health and Nutrition Examination Surveys of 1988-1994 (n=18,800) and 1999-2002 (n=10,283). We compared these two samples with respect to the following outcomes: previously diagnosed diabetes defined by self-report; undiagnosed diabetes defined as fasting plasma glucose > or =126 mg/dl; impaired fasting glucose defined as fasting plasma glucose 100-125 mg/dl; and insulin resistance calculated using the homeostasis model assessment as {[fasting serum insulin (microU/ml)] x [fasting plasma glucose (mmol/L)]/22.5}.

RESULTS

The age- and sex-adjusted prevalence of diagnosed diabetes increased from 5.5% in 1988-1994 to 6.8% in 1999-2002 (change 1.3%, 95% confidence interval 0.5-2.1). Little change occurred in the adjusted prevalence of undiagnosed diabetes (from 3.0 to 3.0%) and impaired fasting glucose (from 26.2 to 26.9%). Mean insulin resistance and the proportion with high insulin resistance increased significantly both among normoglycemic persons (mean: from 2.0 to 2.2; proportion >2.35: from 26.2 to 32.2%) and among persons with undiagnosed diabetes or impaired fasting glucose (mean: from 4.0 to 4.5; proportion >4.4: from 24.8 to 31.1%). In 1999 to 2002, diagnosed and undiagnosed diabetes were most common in non-Hispanic blacks, whereas impaired fasting glucose was most common in Mexican Americans.

CONCLUSIONS

Diabetes, impaired fasting glucose, and insulin resistance are common in the United States and their prevalence continues to increase.

A Refill Adherence Algorithm for Multiple Short Intervals to Estimate Refill Compliance (ReComp)

BACKGROUND

There are many measures of refill adherence available, but few have been designed or validated for use with repeated measures designs and short observation periods.

OBJECTIVE

To design a refill-based adherence algorithm suitable for short observation periods, and compare it to 2 reference measures.

METHODS

A single composite algorithm incorporating information on both medication gaps and oversupply was created. Electronic Veterans Affairs pharmacy data, clinical data, and laboratory data from routine clinical care were used to compare the new measure, ReComp, with standard reference measures of medication gaps (MEDOUT) and adherence or oversupply (MEDSUM) in 3 different repeated measures medication adherence-response analyses. These analyses examined the change in low density lipoprotein (LDL) with simvastatin use, blood pressure with antihypertensive use, and heart rate with beta-blocker use for 30- and 90-day intervals. Measures were compared by regression based correlations (R2 values) and graphical comparisons of average medication adherence-response curves.

RESULTS

In each analysis, ReComp yielded a significantly higher R2 value and more expected adherence-response curve regardless of the length of the observation interval. For the 30-day intervals, the highest correlations were observed in the LDL-simvastatin analysis (ReComp R2 = 0.231; [95% CI, 0.222-0.239]; MEDSUM R2 = 0.054; [95% CI, 0.049-0.059]; MEDOUT R2 = 0.053; [95% CI, 0.048-0.058]).

CONCLUSIONS

ReComp is better suited to shorter observation intervals with repeated measures than previously used measures.

Inhaled corticosteroids and risk of lung cancer among patients with chronic obstructive pulmonary disease

RATIONALE AND OBJECTIVES

Lung cancer is a frequent cause of death among patients with chronic obstructive pulmonary disease (COPD). We examined whether the use of inhaled corticosteroids among patients with COPD was associated with a decreased risk of lung cancer.

METHODS

We performed a cohort study of United States veterans enrolled in primary care clinics between December 1996 and May 2001. Participants had received treatment for, had an International Classification of Disease, 9th edition, diagnosis of, or a self-reported diagnosis of COPD. Patients with a history of lung cancer were excluded. To be exposed, patients must have been at least 80% adherent to inhaled corticosteroids. We used Cox regression models to estimate the risk of cancer and adjust for potential confounding factors.

FINDINGS

We identified 10,474 patients with a median follow-up of 3.8 years. In comparison to nonusers of inhaled corticosteroids, adjusting for age, smoking status, smoking intensity, previous history of non-lung cancer malignancy, coexisting illnesses, and bronchodilator use, there was a dose-dependent decreased risk of lung cancer associated with inhaled corticosteroids (ICS dose < 1,200 mug/d: adjusted HR, 1.3; 95% confidence interval, 0.67-1.90; ICS dose >or= 1,200 microg/d: adjusted HR, 0.39; 95% confidence interval, 0.16-0.96). Changes in cohort definitions had minimal effects on the estimated risk. Analyses examining confounding by indication suggest biases in the opposite direction of the described effects.

INTERPRETATION

Results suggest that inhaled corticosteroids may have a potential role in lung cancer prevention among patients with COPD. These initial findings require confirmation in separate and larger cohorts.