Positive predictive value of the diagnosis of acute myocardial infarction in an administrative database

The effect of systemic psoriasis therapies on the incidence of myocardial infarction: a cohort study

BACKGROUND

Psoriasis confers an independent risk of cardiovascular disease that is likely to be related to systemic inflammation. Anti-inflammatory treatment could theoretically reduce the risk of cardiovascular disease, and initial data suggest that treatment may reduce the incidence of cardiovascular risk factors.

OBJECTIVES

To determine the impact of anti-inflammatory therapy on the risk of acute myocardial infarction (MI) in patients with moderate-to-severe psoriasis.

METHODS

Cohort study using administrative and pharmacy claims data from a large U.S. insurer comparing patients with psoriasis aged ≥ 18 years receiving systemic immunomodulatory therapies (methotrexate, ciclosporin, alefacept, efalizumab, adalimumab, etancercept and infliximab) with a control group treated with ultraviolet B phototherapy that has limited systemic anti-inflammatory effects. The risk of acute MI was calculated using a proportional hazards model while controlling for sex, age, hypertension, hyperlipidaemia, diabetes and depression. Significant interaction terms were included in the final model.

RESULTS

The study group included 25,554 patients with psoriasis receiving systemic treatment or phototherapy. There was a trend towards an increased risk of MI in the systemic treatment group but not a significant difference in overall MI risk [hazard ratio (HR) 1·33, 95% confidence interval (CI) 0·90-1·96]. Additionally, there was a significant interaction with age: in patients under 50 years the HR for MI if receiving systemic therapy was 0·65 (95% CI 0·32-1·34), and in patients aged 50-70 years it was 1·37 (95% CI 0·79-2·38).

CONCLUSIONS

Overall, there does not appear to be a reduced risk of MI in patients with psoriasis receiving systemic therapy compared with a group undergoing phototherapy. The risk of MI may vary by age.

Primary care and health outcomes among older patients with diabetes

OBJECTIVE

The aim of this study was to measure the relationship between days spent waiting for primary care and health outcomes among patients diagnosed with diabetes, especially among the elderly population.

DATA SOURCE

Secondary data from VA administrative databases and Medicare claims.

STUDY DESIGN

This is a retrospective observational study. Outcome variables include primary care utilization, mortality, heart attack, stroke, and ambulatory-care sensitive condition (ACSC) hospitalization. The main explanatory variable of interest is VA primary care wait time. Negative binomial models predict utilization and stacked logistic regression models predict the probability of experiencing each health outcome. Models are stratified by the presence of a selected health condition and age.

PRINCIPAL FINDINGS

Longer wait times were predicted to decrease utilization between 2 and 4 percent. There was no significant relationship between wait times and health outcomes for the overall sample. In stratified analyses, longer waits were associated with undesirable outcomes for those over age 70 with one of the selected health conditions or in certain narrower 5-year age groups, but the overall pattern of results does not indicate a systematic and significant effect.

CONCLUSIONS

There was a modest effect of long wait times on primary care utilization but no robust effect of longer wait times on health outcomes. Waiting for care did not significantly compromise long-term health outcomes for veterans with diabetes.

Design for validation of acute myocardial infarction cases in Mini-Sentinel

PURPOSE

To describe the acute myocardial infarction (AMI) validation project, a test case for health outcome validation within the US Food and Drug Administration-funded Mini-Sentinel pilot program.

METHODS

The project consisted of four parts: (i) case identification-developing an algorithm based on the International Classification of Diseases, Ninth Revision, to identify hospitalized AMI patients within the Mini-Sentinel Distributed Database; (ii) chart retrieval-establishing procedures that ensured patient privacy (collection and transfer of minimum necessary amount of information, and redaction of direct identifiers to validate potential cases of AMI); (iii) abstraction and adjudication-trained nurse abstractors gathered key data using a standardized form with cardiologist adjudication; and (iv) calculation of the positive predictive value of the constructed algorithm.

RESULTS

Key decision points included (i) breadth of the AMI algorithm, (ii) centralized versus distributed abstraction, and (iii) approaches to maintaining patient privacy and to obtaining charts for public health purposes. We used an algorithm limited to International Classification of Diseases, Ninth Revision, codes 410.x0-410.x1. Centralized data abstraction was performed because of the modest number of charts requested (<155). The project's public health status accelerated chart retrieval in most instances.

CONCLUSIONS

We have established a process to validate AMI within Mini-Sentinel, which may be used for other health outcomes. Challenges include the following: (i) ensuring that only minimum necessary data are transmitted by Data Partners for centralized chart review, (ii) establishing procedures to maintain data privacy while still allowing for timely access to medical charts, and (iii) securing access to charts for public health uses that do not require approval from an institutional review board while maintaining patient privacy.

Full coverage for preventive medications after myocardial infarction

BACKGROUND

Adherence to medications that are prescribed after myocardial infarction is poor. Eliminating out-of-pocket costs may increase adherence and improve outcomes.

METHODS

We enrolled patients discharged after myocardial infarction and randomly assigned their insurance-plan sponsors to full prescription coverage (1494 plan sponsors with 2845 patients) or usual prescription coverage (1486 plan sponsors with 3010 patients) for all statins, beta-blockers, angiotensin-converting-enzyme inhibitors, or angiotensin-receptor blockers. The primary outcome was the first major vascular event or revascularization. Secondary outcomes were rates of medication adherence, total major vascular events or revascularization, the first major vascular event, and health expenditures.

RESULTS

Rates of adherence ranged from 35.9 to 49.0% in the usual-coverage group and were 4 to 6 percentage points higher in the full-coverage group (P<0.001 for all comparisons). There was no significant between-group difference in the primary outcome (17.6 per 100 person-years in the full-coverage group vs. 18.8 in the usual-coverage group; hazard ratio, 0.93; 95% confidence interval [CI], 0.82 to 1.04; P=0.21). The rates of total major vascular events or revascularization were significantly reduced in the full-coverage group (21.5 vs. 23.3; hazard ratio, 0.89; 95% CI, 0.90 to 0.99; P=0.03), as was the rate of the first major vascular event (11.0 vs. 12.8; hazard ratio, 0.86; 95% CI, 0.74 to 0.99; P=0.03). The elimination of copayments did not increase total spending ($66,008 for the full-coverage group and $71,778 for the usual-coverage group; relative spending, 0.89; 95% CI, 0.50 to 1.56; P=0.68). Patient costs were reduced for drugs and other services (relative spending, 0.74; 95% CI, 0.68 to 0.80; P<0.001).

CONCLUSIONS

The elimination of copayments for drugs prescribed after myocardial infarction did not significantly reduce rates of the trial's primary outcome. Enhanced prescription coverage improved medication adherence and rates of first major vascular events and decreased patient spending without increasing overall health costs. (Funded by Aetna and the Commonwealth Fund; MI FREEE ClinicalTrials.gov number, NCT00566774.).

Cardiovascular safety of celecoxib in acute myocardial infarction patients: a nested case-control study

The objective was to measure the impact of exposure to coxibs and non-steroidal antiinflammatory drugs (NSAID) on morbidity and mortality in older patients with acute myocardial infarction (AMI). A nested case-control study was carried out using an exhaustive population-based cohort of patients aged 66 years and older living in Quebec (Canada) who survived a hospitalization for AMI (ICD-9 410) between 1999 and 2002. The main variables were all-cause and cardiovascular (CV) death, subsequent hospital admission for AMI, and a composite end-point including recurrent AMI or CV death. Conditional logistic regressions were used to estimate the risk of mortality and morbidity. A total of 19,823 patients aged 66 years and older survived hospitalization for AMI in the province of Quebec between 1999 and 2002. After controlling for covariables, the risk of subsequent AMI and the risk of composite end-point were increased by the use of rofecoxib. The risk of subsequent AMI was particularly high for new rofecoxib users (HR 2.47, 95% CI 1.57–3.89). No increased risk was observed for celecoxib users. No increased risk of CV death was observed for patients exposed to coxibs or NSAIDs. Patients newly exposed to NSAIDs were at an increased risk of death (HR 2.22, 95% CI 1.30–3.77) and of composite end-point (HR 2.28, 95% CI 1.35–3.84). Users of rofecoxib and NSAIDs, but not celecoxib, were at an increased risk of recurrent AMI and of composite end-point. Surprisingly, no increased risk of CV death was observed. Further studies are needed to better understand these apparently contradictory results.

The impact of the aging population on coronary heart disease in the United States

BACKGROUND

The demographic shift toward an older population in the United States will result in a higher burden of coronary heart disease, but the increase has not been quantified in detail. We sought to estimate the impact of the aging US population on coronary heart disease.

METHODS

We used the Coronary Heart Disease Policy Model, a Markov model of the US population between 35 and 84 years of age, and US Census projections to model the age structure of the population between 2010 and 2040.

RESULTS

Assuming no substantive changes in risks factors or treatments, incident coronary heart disease is projected to increase by approximately 26%, from 981,000 in 2010 to 1,234,000 in 2040, and prevalent coronary heart disease by 47%, from 11.7 million to 17.3 million. Mortality will be affected strongly by the aging population; annual coronary heart disease deaths are projected to increase by 56% over the next 30 years, from 392,000 to 610,000. Coronary heart disease-related health care costs are projected to rise by 41% from $126.2 billion in 2010 to $177.5 billion in 2040 in the United States. It may be possible to offset the increase in disease burden through achievement of Healthy People 2010/2020 objectives or interventions that substantially reduce obesity, blood pressure, or cholesterol levels in the population.

CONCLUSIONS

Without considerable changes in risk factors or treatments, the aging of the US population will result in a sizeable increase in coronary heart disease incidence, prevalence, mortality, and costs. Health care stakeholders need to plan for the future age-related health care demands of coronary heart disease.

The burden of depression in prostate cancer

OBJECTIVE

We sought to analyze the prevalence and incremental burden of depression among elderly with prostate cancer.

METHODS

We adopted a retrospective cohort design using the Surveillance, Epidemiology and End Results-Medicare linked database between 1995 and 2003. Patients with prostate cancer diagnosed between 1995 and 1998 were identified and followed retrospectively for 1 year pre-diagnosis and up to 8 years post diagnosis. In this cohort of patients with prostate cancer, depression during treatment phase (1 year after diagnosis of prostate cancer) or in the follow-up phase was identified using the International Classification of Diseases-Ninth Revision depression-related codes. Poisson, general linear (log-link) and Cox regression models were used to determine the association between depression status during treatment and follow-up phases and outcomes-health resource utilization, cost and mortality.

RESULTS

Of the 50,147 patients newly diagnosed with prostate cancer, 4285 (8.54%) had a diagnosis of depression. A diagnosis of depression during treatment phase was associated with higher odds of emergency room visits (odds ratio (OR) = 4.45, 95% CI = 4.13, 4.80), hospitalizations (OR = 3.22, CI = 3.08, 3.37), outpatient visits (OR = 1.71, CI = 1.67, 1.75) and excess risk of death over the course of the follow-up interval (hazard ratio = 2.82, CI = 2.60, 3.06). Health care costs associated with depression remained elevated compared with costs for men without depression, over the course of the follow-up.

CONCLUSIONS

Depression during the treatment phase was associated with significant health resource utilization, costs and mortality among men with prostate cancer. These findings emphasize the need to effectively identify and treat depression in the setting of prostate cancer.

Use of administrative data to identify colorectal liver metastasis

BACKGROUND

The ability to identify patients with colorectal cancer (CRC) liver metastasis (LM) using administrative data is unknown. The goals of this study were to evaluate whether administrative data can accurately identify patients with CRCLM and to develop a diagnostic algorithm capable of identifying such patients.

MATERIALS AND METHODS

A retrospective cohort study was conducted to validate the diagnostic and procedural codes found in administrative databases of the Veterans Administration (VA) system. CRC patients evaluated at a major VA center were identified (1997-2008, n = 1671) and classified as having liver-specific ICD-9 and/or CPT codes. The presence of CRCLM was verified by primary chart abstraction in the study sample. Contingency tables were created and the positive predictive value (PPV) for CRCLM was calculated for each candidate administrative code. A multivariate logistic-regression model was used to identify independent predictors (codes) of CRCLM, which were used to develop a diagnostic algorithm. Validity of the algorithm was determined by discrimination (c-statistic) of the model and PPV of the algorithm.

RESULTS

Multivariate logistic regression identified ICD-9 diagnosis codes 155.2 (OR 9.7 [95% CI 2.5-38.4]) and 197.7 (84.6 [52.9-135.3]), and procedure code 50.22 (5.9 [1.3-25.5]) as independent predictors of CRCLM diagnosis. The model's discrimination was 0.89. The diagnostic algorithm, defined as the presence of any of these codes, had a PPV of 87%.

CONCLUSIONS

VA administrative databases reliably identify patients with CRCLM. This diagnostic algorithm is highly predictive of CRCLM diagnosis and can be used for research studies evaluating population-level features of this disease within the VA system.

The risk of incident coronary heart disease among veterans with and without HIV and hepatitis C

BACKGROUND

Whether hepatitis C virus (HCV) confers additional coronary heart disease (CHD) risk among human immunodeficiency virus (HIV) infected individuals is unclear. Without appropriate adjustment for antiretroviral therapy, CD4 count, and HIV-1 RNA and substantially different mortality rates among those with and without HIV and HCV infection, the association between HIV, HCV, and CHD may be obscured.

METHODS AND RESULTS

We analyzed data on 8579 participants (28% HIV+, 9% HIV+HCV+) from the Veterans Aging Cohort Study Virtual Cohort who participated in the 1999 Large Health Study of Veteran Enrollees. We analyzed data collected on HIV and HCV status, risk factors for and the incidence of CHD, and mortality from January 2000 to July 2007. We compared models to assess CHD risk when death was treated as a censoring event and as a competing risk. During the median 7.3 years of follow-up, there were 194 CHD events and 1186 deaths. Compared with HIV-HCV- Veterans, HIV+HCV+ Veterans had a significantly higher risk of CHD regardless of whether death was adjusted for as a censoring event (adjusted hazard ratio, 2.03; 95% confidence interval, 1.28 to 3.21) or a competing risk (adjusted HR, 2.45; 95% confidence interval, 1.83 to 3.27 respectively). Compared with HIV+HCV- Veterans, HIV+HCV+ Veterans also had a significantly higher adjusted risk of CHD regardless of whether death was treated as a censored event (adjusted hazard ratio, 1.93; 95% confidence interval, 1.02 to 3.62) or a competing risk (adjusted hazard ratio, 1.46; 95% confidence interval, 1.03 to 2.07).

CONCLUSIONS

HIV+HCV+ Veterans have an increased risk of CHD compared with HIV+HCV- and HIV-HCV- Veterans.

Outcomes of hospitalized patients with non-acute coronary syndrome and elevated cardiac troponin level

OBJECTIVE

Cardiac troponin levels help risk-stratify patients presenting with an acute coronary syndrome. Although cardiac troponin levels may be elevated in patients presenting with non-acute coronary syndrome conditions, specific diagnoses and long-term outcomes within that cohort are unclear.

METHODS

By using the Veterans Affairs centralized databases, we identified all hospitalized patients in 2006 who had a troponin assay obtained during their initial reference hospitalization. On the basis of the diagnostic codes of the International Classification of Diseases, 9th Revision, primary diagnoses were categorized as acute coronary syndrome or non-acute coronary syndrome conditions.

RESULTS

Of a total of 21,668 patients with an elevated troponin level who were discharged from the hospital, 12,400 (57.2%) had a non-acute coronary syndrome condition. Among that cohort, the most common diagnostic category involved the cardiovascular system, and congestive heart failure (N=1661) and chronic coronary artery disease (N=1648) accounted for the major classifications. At 1 year after hospital discharge, mortality in patients with a non-acute coronary syndrome condition was 22.8% and was higher than in the acute coronary syndrome cohort (odds ratio 1.39; 95% confidence interval, 1.30-1.49). Despite the high prevalence of cardiovascular diseases in patients with a non-acute coronary syndrome diagnosis, use of cardiac imaging within 90 days of hospitalization was low compared with that in patients with acute coronary syndrome (odds ratio 0.25; 95% confidence interval, 0.23-0.27).

CONCLUSIONS

Hospitalized patients with an elevated troponin level more often have a primary diagnosis that is not an acute coronary syndrome. Their long-term survival is poor and justifies novel diagnostic or therapeutic strategy-based studies to target the highest risk subsets before hospital discharge.

Cardiovascular events and death in children exposed and unexposed to ADHD agents

OBJECTIVE

The objective of this study was to compare the rate of severe cardiovascular events and death in children who use attention-deficit/hyperactivity disorder (ADHD) medications versus nonusers.

PATIENTS AND METHODS

We performed a large cohort study using data from 2 administrative databases. All children aged 3 to 17 years with a prescription for an amphetamine, atomoxetine, or methylphenidate were included and matched with up to 4 nonusers on the basis of data source, gender, state, and age. Cardiovascular events were validated using medical records. Proportional hazards regression was used to calculated hazard ratios.

RESULTS

We identified 241 417 incident users (primary cohort). No statistically significant difference between incident users and nonusers was observed in the rate of validated sudden death or ventricular arrhythmia (hazard ratio: 1.60 [95% confidence interval (CI): 0.19-13.60]) or all-cause death (hazard ratio: 0.76 [95% CI: 0.52-1.12]). None of the strokes identified during exposed time to ADHD medications were validated. No myocardial infarctions were identified in ADHD medication users. No statistically significant difference between prevalent users and nonusers (secondary cohort) was observed (hazard ratios for validated sudden death or ventricular arrhythmia: 1.43 [95% CI: 0.31-6.61]; stroke: 0.89 [95% CI: 0.11-7.11]; stroke/myocardial infarction: 0.72 [95% CI: 0.09-5.57]; and all-cause death: 0.77 [95% CI: 0.56-1.07).

CONCLUSIONS

The rate of cardiovascular events in exposed children was very low and in general no higher than that in unexposed control subjects. Because of the low number of events, we have limited ability to rule out relative increases in rate.

Characteristics and VA health care utilization of U.S. Veterans who completed suicide in Oregon between 2000 and 2005

Oregon Violent Death Reporting System data were linked with Veterans Affairs (VA) administrative data to identify and describe veterans who completed suicide in Oregon from 2000 to 2005 (n = 968), and to describe their VA health care utilization in the year prior to death. Twenty-two percent had received health care in the VA system. Of these, 57% did not have mental health diagnoses and 58% had not seen mental health professionals. A larger proportion of those who accessed care were VA-enrolled and received service-connected disability benefits. Fifty-five veterans were hospitalized during the year prior to death. Of these, 33% completed suicide within 30 days of a hospitalization. Further development of suicide prevention strategies for veterans in the community, including general medical treatment settings, is indicated.

Adherence to statin therapy in elderly patients after hospitalization for coronary revascularization

Low levels of statin adherence have been documented in patients with coronary artery disease (CAD), but whether coronary revascularization is associated with improved adherence rates has yet to be evaluated. We identified all Medicare beneficiaries enrolled in 2 statewide pharmacy assistance programs who were ≥65 years old, who had been hospitalized for CAD from 1995 through 2004, and who had been prescribed statin therapy within 90 days of discharge (n = 13,130). Statin adherence was measured based on the proportion of days covered with statin therapy after hospital discharge, and full adherence was defined as proportion of days covered ≥80%. Statin adherence was compared in patients with CAD treated with medical therapy (n = 3,714), percutaneous coronary intervention (n = 6,309), or coronary artery bypass graft surgery (n = 3,107). Statin adherence significantly increased over the period of the study from 70.5% to 75.4% (p <0.0001). After hospitalization for CAD, patients treated with percutaneous coronary intervention and coronary artery bypass graft surgery had full adherence rates of 70.6% and 70.2%, respectively. Full adherence rates were significantly lower for patients treated with coronary revascularization compared to patients treated with medical therapy (79.4%, p <0.0001). Independent predictors of higher statin adherence included treatment with medical therapy, later year of hospital admission, white race, previous statin use, and use of other cardiac medications after CAD hospitalization (p <0.01 for all comparisons). In conclusion, in patients receiving invasive coronary treatment, statin adherence remains suboptimal, despite strong evidence supporting their use. Given the health and economic consequences of nonadherence, these findings highlight the need for developing cost-effective strategies to improve medication adherence after coronary revascularization.

Risk of heart failure with human immunodeficiency virus in the absence of prior diagnosis of coronary heart disease

BACKGROUND

Whether human immunodeficiency virus (HIV) infection is a risk factor for heart failure (HF) is not clear. The presence of coronary heart disease and alcohol consumption in this population may confound this association.

METHODS

To determine whether HIV infection is a risk factor for incident HF, we conducted a population-based, retrospective cohort study of HIV-infected and HIV-uninfected veterans enrolled in the Veterans Aging Cohort Study Virtual Cohort (VACS-VC) and the 1999 Large Health Study of Veteran Enrollees (LHS) from January 1, 2000, to July 31, 2007.

RESULTS

There were 8486 participants (28.2% HIV-infected) enrolled in the VACS-VC who also participated in the 1999 LHS. During the median 7.3 years of follow-up, 286 incident HF events occurred. Age- and race/ethnicity-adjusted HF rates among HIV-infected and HIV-uninfected veterans were 7.12 (95% confidence interval [CI], 6.90-7.34) and 4.82 (95% CI, 4.72-4.91) per 1000 person-years, respectively. Compared with HIV-uninfected veterans, those who were HIV infected had an increased risk of HF (adjusted hazard ratio [HR], 1.81; 95% CI, 1.39-2.36). This association persisted among veterans who did not have a coronary heart disease event or a diagnosis related to alcohol abuse or dependence before the incident HF event (adjusted HR, 1.96; 95% CI, 1.29-2.98). Compared with HIV-uninfected veterans, those who were HIV infected with a baseline Human immunodeficiency virus 1 (HIV-1) RNA level of 500 or more copies/mL had a higher risk of HF (adjusted HR, 2.28; 95% CI, 1.57-3.32), while those with baseline and a recent HIV-1 RNA level less than 500 copies/mL did not (adjusted HR, 1.10; 95% CI,  0.64-1.89; P < .001 for comparison between high and low HIV-1 RNA groups).

CONCLUSIONS

Our data suggest that HIV infection is a risk factor for HF. Ongoing viral replication is associated with a higher risk of developing HF.

Recent US Patterns and Predictors of Prevalent Diabetes among Acute Myocardial Infarction Patients

Background. Diabetes mellitus (DM) confers high vascular risk and is a growing national epidemic. We assessed clinical characteristics and prevalence of diagnosed DM among patients hospitalized with acute myocardial infarction (AMI) in the US over the last decade. Methods. Data were obtained from all states within the US that contributed to the Nationwide Inpatient Sample. All patients admitted to hospitals between 1997 and 2006 with a primary discharge diagnosis of AMI were included. Time trends in the proportion of these patients with DM diagnosis were computed. Results. The portion of patients with comorbid diabetes among AMI hospitalizations increased substantially from 18% in 1997 to 30% in 2006 (P < .0001). Absolute numbers of AMI hospitalizations in the US decreased 8% (from 729, 412 to 672, 243), while absolute numbers of AMI hospitalizations with coexisting DM rose 51% ((131, 189 to 198, 044), both (P < .0001). Women with AMI were significantly more likely to have DM than similarly aged men, but these differences diminished with increasing age. Conclusion. Although overall hospitalizations for AMI in the US diminished over the last decade, prevalence of diabetes rose substantially. This may have important consequences for the future societal vascular disease burden.

Effectiveness and cost-effectiveness of blood pressure screening in adolescents in the United States

OBJECTIVE

To compare the long-term effectiveness and cost-effectiveness of 3 approaches to managing elevated blood pressure (BP) in adolescents in the United States: no intervention, "screen-and-treat," and population-wide strategies to lower the entire BP distribution.

STUDY DESIGN

We used a simulation model to combine several data sources to project the lifetime costs and cardiovascular outcomes for a cohort of 15-year-old U.S. adolescents under different BP approaches and conducted cost-effectiveness analysis. We obtained BP distributions from the National Health and Nutrition Examination Survey 1999-2004 and used childhood-to-adult longitudinal correlation analyses to simulate the tracking of BP. We then used the coronary heart disease policy model to estimate lifetime coronary heart disease events, costs, and quality-adjusted life years (QALY).

RESULTS

Among screen-and-treat strategies, finding and treating the adolescents at highest risk (eg, left ventricular hypertrophy) was most cost-effective ($18000/QALY [boys] and $47000/QALY [girls]). However, all screen-and-treat strategies were dominated by population-wide strategies such as salt reduction (cost-saving [boys] and $650/QALY [girls]) and increasing physical education ($11000/QALY [boys] and $35000/QALY [girls]).

CONCLUSIONS

Routine adolescents BP screening is moderately effective, but population-based BP interventions with broader reach could potentially be less costly and more effective for early cardiovascular disease prevention and should be implemented in parallel.

Screening for depression in patients with hepatitis C using the Beck Depression Inventory-II: do somatic symptoms compromise validity?

OBJECTIVE

The objective of the study was to evaluate the validity of the Beck Depression Inventory-II (BDI-II) when used to measure depression in patients with hepatitis C virus (HCV).

METHOD

Factor analysis was utilized to validate the BDI-II in a sample of 671 patients with HCV recruited from a large Veterans Affairs medical center. The data were split randomly: the first half was subjected to exploratory factor analysis, and confirmatory factor analysis was used with the second half to confirm the model. Diagnostic data were retrieved from the electronic medical records.

RESULTS

Subjects were 97.0% male, average age was 52.8 years, 16.1% had a cirrhosis diagnosis, 62.9% had a current major depressive disorder diagnosis, and 42.3% endorsed significant depressive symptoms on the BDI-II. A two-factor model was an excellent fit for the data; the factors were labeled Cognitive-Affective and Somatic. Patients scored significantly higher on the Somatic factor than on the Cognitive-Affective factor (P<.001), and this discrepancy increased when comparing patients based on whether they had a diagnosis of cirrhosis.

CONCLUSIONS

When screening for depression in HCV patients, questions targeting cognitive and affective symptoms of depression may provide a more valid measurement of depression than questions targeting somatic symptoms of depression, particularly for patients with more advanced liver disease.

Validity of selected Patient Safety Indicators: opportunities and concerns

BACKGROUND

The Agency for Healthcare Research and Quality (AHRQ) recently designed the Patient Safety Indicators (PSIs) to detect potential safety-related adverse events. The National Quality Forum has endorsed several of these ICD-9-CM-based indicators as quality-of-care measures. We examined the positive predictive value (PPV) of 3 surgical PSIs: postoperative pulmonary embolus and deep vein thrombosis (pPE/DVT), iatrogenic pneumothorax (iPTX), and accidental puncture and laceration (APL).

STUDY DESIGN

We applied the AHRQ PSI software (v.3.1a) to fiscal year 2003 to 2007 Veterans Health Administration (VA) administrative data to identify (flag) patients suspected of having a pPE/DVT, iPTX, or APL. Two trained nurse abstractors reviewed a sample of 336 flagged medical records (112 records per PSI) using a standardized instrument. Inter-rater reliability was assessed.

RESULTS

Of 2,343,088 admissions, 6,080 were flagged for pPE/DVT (0.26%), 1,402 for iPTX (0.06%), and 7,203 for APL (0.31%). For pPE/DVT, the PPV was 43% (95% CI, 34% to 53%); 21% of cases had inaccurate coding (eg, arterial not venous thrombosis); and 36% featured thromboembolism present on admission or preoperatively. For iPTX, the PPV was 73% (95% CI, 64% to 81%); 18% had inaccurate coding (eg, spontaneous pneumothorax), and 9% were pneumothoraces present on admission. For APL, the PPV was 85% (95% CI, 77% to 91%); 10% of cases had coding inaccuracies and 5% indicated injuries present on admission. However, 27% of true APLs were minor injuries requiring no surgical repair (eg, small serosal bowel tear). Inter-rater reliability was >90% for all 3 PSIs.

CONCLUSIONS

Until coding revisions are implemented, these PSIs, especially pPE/DVT, should be used primarily for screening and case-finding. Their utility for public reporting and pay-for-performance needs to be reassessed.

Accuracy of VA databases for diagnoses of knee replacement and hip replacement

PURPOSE

To examine the validity of International Classification of Diseases-Ninth Revision (ICD-9) and Current Procedural Terminology (CPT) codes for knee replacement and hip replacement in Veterans Affairs (VA) databases.

METHODS

From a cohort of veterans who received health care at Minneapolis VA Medical Center and/or affiliated medical facilities, we obtained four random samples of 50 patients each with: neither hip nor knee replacement code, knee replacement code only, hip replacement code only and both knee and hip replacement codes. The gold standard was documentation of knee or hip replacement surgery in patient medical records. Accuracy of ICD-9 or CPT code for knee and hip replacement was assessed by calculating sensitivity, specificity, positive and negative predictive values (PPV and NPV).

RESULTS

Of the 200 patients, medical records were available for 166:140 (70%) had complete medical records and 26 (13%) had incomplete medical records. Knee replacement codes were accurate with excellent PPV of 95%, sensitivity of 95%, specificity of 96% and NPV of 96%. Hip replacement codes were accurate with excellent PPV of 98%, sensitivity of 96%, specificity of 99% and NPV of 96%. Sensitivity analyses that included incomplete charts had little impact on these estimates. The procedure dates found in VA databases matched exactly with medical records in 96%.

CONCLUSIONS

The ICD-9 and CPT codes for knee replacement and hip replacement in VA databases are valid. These codes may be used to identify cohorts of veterans with knee replacement and hip replacement for research studies.

Trends in mortality of acute myocardial infarction after discharge from the hospital

BACKGROUND

We assessed trends in the prognosis of patients with acute myocardial infarction hospitalized in New Jersey hospitals. In recent decades, in-hospital mortality has declined markedly but the decline in longer-term mortality is less pronounced, implying that mortality after discharge has worsened.

METHODS AND RESULTS

Using the Myocardial Infarction Data Acquisition System (MIDAS), we examined the outcomes of 285 397 patients hospitalized for a first acute myocardial infarction between 1986 and 2007. Mortality at discharge decreased by 9.4% from 16.9% to 7.5% (annual change, -0.44; 95% confidence interval, -0.49 to -0.40), but the decrease at 1 year was less pronounced (6.4%) because of an increase in mortality from discharge to 1 year after discharge (from 12.1% to 13.9%; annual change, +0.15; 95% confidence interval, +0.10 to +0.20). Mortality from 30 days after discharge to 1 year, a measure not affected by length of stay, increased by 1.2% (annual change, +0.10; 95% confidence interval, +0.06 to +0.23). The effect was more evident in the older age groups and was due to noncardiovascular mortality, especially from respiratory and renal diseases, septicemia, and cancer. All effects remained statistically significant (P<0.0001) after adjustment for demographics, comorbidities, infarction type, complications, and interventions. Piecewise linear regressions confirmed these trends.

CONCLUSIONS

Postdischarge mortality of patients with acute myocardial infarction is increasing, primarily because of higher noncardiovascular mortality in the older age groups.

A classification of diabetic foot infections using ICD-9-CM codes: application to a large computerized medical database

Background

Diabetic foot infections are common, serious, and varied. Diagnostic and treatment strategies are correspondingly diverse. It is unclear how patients are managed in actual practice and how outcomes might be improved. Clarification will require study of large numbers of patients, such as are available in medical databases. We have developed and evaluated a system for identifying and classifying diabetic foot infections that can be used for this purpose.

Methods

We used the (VA) Diabetes Epidemiology Cohorts (DEpiC) database to conduct a retrospective observational study of patients with diabetic foot infections. DEpiC contains computerized VA and Medicare patient-level data for patients with diabetes since 1998. We determined which ICD-9-CM codes served to identify patients with different types of diabetic foot infections and ranked them in declining order of severity: Gangrene, Osteomyelitis, Ulcer, Foot cellulitis/abscess, Toe cellulitis/abscess, Paronychia. We evaluated our classification by examining its relationship to patient characteristics, diagnostic procedures, treatments given, and medical outcomes.

Results

There were 61,007 patients with foot infections, of which 42,063 were classifiable into one of our predefined groups. The different types of infection were related to expected patient characteristics, diagnostic procedures, treatments, and outcomes. Our severity ranking showed a monotonic relationship to hospital length of stay, amputation rate, transition to long-term care, and mortality.

Conclusions

We have developed a classification system for patients with diabetic foot infections that is expressly designed for use with large, computerized, ICD-9-CM coded administrative medical databases. It provides a framework that can be used to conduct observational studies of large numbers of patients in order to examine treatment variation and patient outcomes, including the effect of new management strategies, implementation of practice guidelines, and quality improvement initiatives.

Disparities between rural and urban areas for osteoporosis management in the province of Quebec following the Canadian 2002 guidelines publication

RATIONALE, AIMS AND OBJECTIVES

Clinical guidelines have been seen as a tool for improving management of osteoporosis in order to prevent fragility fractures. However, the impact of guidelines on clinical management of osteoporosis has not been measured. We examined medical investigation and treatment before and after the 2002 Canadian guidelines publication and examined if practice changes were different between rural and urban areas.

METHODS

We conducted a retrospective population-based observational study using secondary data analysis. Two studied populations were selected; one before, the other after the publication of Canadian practice guidelines. The studied populations consisted of all individuals 65 years or older from Quebec (Canada) for whom a physician claimed a consultation or have been hospitalized for fragility fracture between the two predefined periods.

RESULTS

There was no significant difference in the rate of bone mineral density testing for women before and after guidelines publication. For men a statistically significant increase was observed but remained very low. A significant increase in bisphosphonates prescribing, but no increased in the reporting of a diagnosis of osteoporosis were observed. A significant reduction of hormonal replacement therapy was seen during the year following guidelines publication. The strongest significant increases were mostly seen in urban regions compared to rural areas.

CONCLUSIONS

Very small changes were observed for diagnostic recognition by physicians, diagnostic testing and some recommended drugs prescribing following guidelines publication. This suggests low guidelines impact on medical practice for osteoporosis in patients suffering fragility fractures.

Non-aspirin NSAIDs, cyclooxygenase-2 inhibitors and risk for cardiovascular events-stroke, acute myocardial infarction, and death from coronary heart disease

PURPOSE

To determine if certain non-steroidal anti-inflammatory drugs (NSAIDs) are associated with increased risk of cardiovascular events: acute myocardial infarction (AMI), stroke, and death from coronary heart disease (CHD).

METHODS

We conducted a retrospective cohort study of Tennessee Medicaid enrollees aged 35-94 years between 1 January 1999 and 31 December 2005. Eligible persons were non-institutionalized, had continuous enrollment, and had no serious illness prior to cohort entry. Exposure to celecoxib, rofecoxib, valdecoxib, ibuprofen, naproxen, diclofenac, and indomethacin was studied. The outcome was hospitalization for AMI, stroke, or death from CHD among those with and without a history of cardiovascular disease (CVD). Adjusted hazard ratios (aHR) and 95% confidence intervals (95% CI) are reported.

RESULTS

There were 610 001 persons in the final cohort and 14% had a baseline history of CVD. In those without CVD (N = 525 249) there were 1 566 678 person-years of follow-up and 12 184 events. In this group, non-users had 7.90 events/1000 person-years. Events/1000 person-years were 10.41 for current use of celecoxib (aHR 1.00, 95% CI 0.89-1.13), 10.91 for rofecoxib (aHR 1.21, 95% CI 1.07-1.37), 12.46 for valdecoxib (aHR 1.30 95% CI 1.04-1.61), and 13.25 for indomethacin (aHR 1.36, 95% CI 1.11-1.66) compared to non-users. Among patients with a past history of CVD (N = 84 752) there were 397 977 person-years of follow-up and 10 248 events. Non-users had 28.30 events/1000 person-years. Among those with CVD, rofecoxib use was associated with increased event rate (30.28 events/1000 person-years [aHR 1.21, 95% CI 1.08-1.37]) and naproxen was associated with a decreased event rate (22.66 events/1000 person-years [aHR 0.88, 95% CI 0.79-0.99]). Among new users, the results were similar except risk among naproxen users was no longer different than non-users.

CONCLUSIONS

We found an increased risk of cardiovascular events among all and new current users of rofecoxib, valdecoxib, and indomethacin in patients with no history of CVD. Among patients with CVD, all and new current rofecoxib use was associated with an increased risk of a cardiovascular event.

Effectiveness of rosuvastatin compared to other statins for the prevention of cardiovascular events-a cohort study in 395 039 patients from clinical practice

PURPOSE

This study compared the effectiveness of rosuvastatin (RSV) to other statins prescribed in clinical practice in prevention of cardiovascular (CV) events.

METHODS

This longitudinal inception cohort study, using Thomson Healthcare's MarketScan databases, included patients aged > or = 18 starting statin therapy during August 2003-December 2005. Patients were followed until 90 days after index statin monotherapy exposure, start of another lipid-lowering therapy, an event, end of eligibility, or end of study. The primary endpoint was a composite of CV death (in-hospital only), myocardial infarction, unstable angina, coronary revascularization, stroke, and carotid revascularization. Adjusted time-to-event analyses incorporating a propensity score covariate were used, and analyses were stratified by duration of statin exposure.

RESULTS

Among 395 039 patients who met inclusion/exclusion criteria, 12% initiated RSV, and 9622 (2.4%) of the total patient population experienced an outcome event. The median duration of statin treatment and follow-up was 100 days and 180 days, respectively. No statistically significant difference in CV event rates between RSV and other statins was observed after adjustment for demographics and medical/prescription history (HR = 0.99, 95%CI = 0.93-1.06). However, with longer exposure time, there was a suggestion of increased benefit with RSV compared to other statins.

CONCLUSIONS

The primary analysis showed similar incidence rates of CV-related events between the statin cohorts over a median of 180 days of follow-up.

Changes in U.S. hospitalization and mortality rates following smoking bans

U.S. state and local governments have increasingly adopted restrictions on smoking in public places. This paper analyzes nationally representative databases, including the Nationwide Inpatient Sample, to compare short-term changes in mortality and hospitalization rates in smoking-restricted regions with control regions. In contrast with smaller regional studies, we find that smoking bans are not associated with statistically significant short-term declines in mortality or hospital admissions for myocardial infarction or other diseases. An analysis simulating smaller studies using subsamples reveals that large short-term increases in myocardial infarction incidence following a smoking ban are as common as the large decreases reported in the published literature.

Diabetes and cardiovascular disease during androgen deprivation therapy: observational study of veterans with prostate cancer

BACKGROUND

Previous studies indicate that androgen deprivation therapy for prostate cancer is associated with diabetes and cardiovascular disease among older men. We evaluated the relationship between androgen deprivation therapy and incident diabetes and cardiovascular disease in men of all ages with prostate cancer.

METHODS

We conducted an observational study of 37,443 population-based men who were diagnosed with local or regional prostate cancer in the Veterans Healthcare Administration from January 1, 2001, through December 31, 2004, with follow-up through December 31, 2005. Cox proportional hazards models were used to assess whether androgen deprivation therapy with gonadotropin-releasing hormone (GnRH) agonists, oral antiandrogens, the combination of the two (ie, combined androgen blockade), or orchiectomy was associated with diabetes, coronary heart disease, myocardial infarction, sudden cardiac death, or stroke, after adjustment for patient and tumor characteristics. All statistical tests were two-sided.

RESULTS

Overall, 14,597 (39%) of the 37,443 patients were treated with androgen deprivation therapy. Treatment with GnRH agonists was associated with statistically significantly increased risks of incident diabetes (for GnRH agonist therapy, 159.4 events per 1000 person-years vs 87.5 events for no androgen deprivation therapy, difference = 71.9, 95% confidence interval [CI] = 71.6 to 72.2; adjusted hazard ratio [aHR] = 1.28, 95% CI = 1.19 to 1.38), incident coronary heart disease (aHR = 1.19, 95% CI = 1.10 to 1.28), myocardial infarction (12.8 events per 1000 person-years for GnRH agonist therapy vs 7.3 for no androgen deprivation therapy, difference = 5.5, 95% CI = 5.4 to 5.6; aHR = 1.28, 95% CI = 1.08 to 1.52), sudden cardiac death (aHR = 1.35, 95% CI = 1.18 to 1.54), and stroke (aHR = 1.22, 95% CI = 1.10 to 1.36). Combined androgen blockade was statistically significantly associated with an increased risk of incident coronary heart disease (aHR = 1.27, 95% CI = 1.05 to 1.53), and orchiectomy was associated with coronary heart disease (aHR = 1.40, 95% CI = 1.04 to 1.87) and myocardial infarction (aHR = 2.11, 95% CI = 1.27 to 3.50). Oral antiandrogen monotherapy was not associated with any outcome studied.

CONCLUSION

Androgen deprivation therapy with GnRH agonists was associated with an increased risk of diabetes and cardiovascular disease.

Cardiovascular benefit of magnitude of low-density lipoprotein cholesterol reduction: a comparison of subgroups by age

BACKGROUND

We examined the effect of the magnitude of low-density lipoprotein cholesterol (LDL-C) reduction across subjects of various ages in a retrospective cohort study.

METHODS AND RESULTS

We selected 20,132 male veterans at high risk for an acute cardiovascular event and who had 2 or more LDL-C measurements before their first documented acute myocardial infarction, revascularization, death, or censoring date. LDL-C reduction was categorized as no reduction (<10 mg/dL; reference), small reduction (between 10 and 40 mg/dL), moderate reduction (between 40 and 70 mg/dL), or large reduction (> or =70 mg/dL). The primary outcome was combined acute myocardial infarction or revascularization. The first and last LDL-C levels in the databases were used to calculate the LDL-C reduction in patients who experienced no outcome or who died. Within each age quartile and in a subgroup of patients > or =80 years of age, a Cox proportional hazards model was used to determine hazard ratios for each category of LDL-C reduction compared with the reference category, with adjustment for age, body mass index, current smoking status, medications, and comorbidities. In all age groups, the magnitude of LDL-C reduction was proportional to the magnitude of cardiovascular risk reduction. Risk reduction for the combined outcome in patients who achieved a large LDL-C reduction was similar in all age quartiles, with multivariate-adjusted hazard ratios of approximately 0.30.

CONCLUSIONS

In a cohort of veterans at high risk for cardiovascular events, patients of all ages, including those 80 years or older, benefitted the most from large reductions in LDL-C.

Accuracy of Veterans Affairs databases for diagnoses of chronic diseases

INTRODUCTION

Epidemiologic studies usually use database diagnoses or patient self-report to identify disease cohorts, but no previous research has examined the extent to which self-report of chronic disease agrees with database diagnoses in a Veterans Affairs (VA) health care setting.

METHODS

All veterans who had a medical care visit from October 1, 1996, through May 31, 1998, at any of the Veterans Integrated Service Network 13 facilities were surveyed about physician diagnosis of chronic obstructive pulmonary disease (COPD)/asthma, depression, diabetes, and heart disease. Four administrative case definitions (data from VA databases) consisting of combinations of International Classification of Diseases, Ninth Revision, codes and disease-specific medication data were compared with self-report of each disease to assess sensitivity, specificity, positive and negative predictive values, area under receiver operating characteristics curve, and kappa statistic.

RESULTS

Sensitivity for administrative definitions compared with self-report of physician diagnosis was 24% to 54% for COPD/asthma, 25% to 47% for depression, 27% to 59% for heart disease, and 64% to 78% for diabetes. Specificity was 88% to 100% for all diseases. The kappa statistic showed fair agreement for COPD/asthma, depression, and heart disease and substantial agreement for diabetes.

CONCLUSION

Diagnoses identified from databases agree with self-report for diabetes but not COPD/asthma, depression, or heart disease in a VA health care setting.

Effect of comorbidity on quality of life of male veterans with prevalent primary total knee arthroplasty

This is a study of the impact of specific and overall comorbidity on health-related quality of life (HRQoL) in men with primary total knee arthroplasty (TKA). In a population-based sample of male veterans who responded to a cross-sectional survey using the validated short-form 36 for veterans (SF-36 V) and had undergone primary TKA prior to survey, eight SF-36 V domain and two summary scores (physical and mental component (PCS and MCS) summary) were compared using multivariable-adjusted multiple linear regressions between patients with and without five comorbidities--chronic obstructive pulmonary disease (COPD)/asthma, diabetes, depression, hypertension, and heart disease. Analyses were adjusted for age, five comorbidities, and time since TKA. Two hundred ninety-three male patients constituted the analytic set with mean (SD) age of 70.3 (8.8) years; 97% were Caucasian and mean (SD) duration since TKA was 2.1 (0.7) years. COPD/asthma was associated with significantly lower adjusted MCS (mean +/- standard error of mean, 47.1 +/- 0.7 vs. 43.1 +/- 1.2; p Collapse

Key Words

• comorbidity
• health-related quality of life
• hrqol
• knee arthroplasty
• quality of life
• total knee arthroplasty

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MESH Headings

• Aged
• Aged, 80 and over
• Arthroplasty, Replacement, Knee/statistics & numerical data
• Comorbidity
• Cross-Sectional Studies
• Depression/epidemiology
• Diabetes Mellitus/epidemiology
• Heart Diseases/epidemiology
• Humans
• Hypertension/epidemiology
• Linear Models
• Male
• Midwestern United States/epidemiology
• Multivariate Analysis
• Prevalence
• Pulmonary Disease, Chronic Obstructive/epidemiology
• Quality of Life
• Rheumatic Diseases/epidemiology
• Rheumatic Diseases/psychology
• Veterans/statistics & numerical data

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Grants

• KL2 RR024151 NCRR NIH HHS
• 1 KL2 RR024151-01 NCRR NIH HHS

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Affiliation(s)

Jasvinder A Singh Rheumatology Section, Medicine Service, Minneapolis VA Medical Center, Minneapolis, MN 55417, USA.

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Collaborators Collapse

Discordance Between Self-report of Physician Diagnosis and Administrative Database Diagnosis of Arthritis and Its Predictors

Objective.

To study predictors of discordance between self-reported physician diagnosis and administrative database diagnosis of arthritis.

Methods.

A cohort of all veterans who utilized Veterans Integrated Service Network (VISN)-13 medical facilities were mailed a questionnaire that included patient self-report of physician diagnosis of arthritis and questions regarding demographics, functional limitation, and SF-36V (a validated version of the Medical Outcomes Study Short-Form 36). Kappa coefficient was used to assess the extent of agreement between self-report of physician diagnosis and administrative database definitions that incorporated International Classification of Diseases (ICD) codes and use of medications for arthritis. We identified predictors of overall discordance between self-report and administrative database diagnosis using multivariable logistic regression analyses.

Results.

Among 70,334 eligible veterans surveyed, 19,749 subjects had an ICD diagnosis of arthritis in the administrative database in the year prior to the survey; 34,440 answered the arthritis question and 18,464 self-reported a physician diagnosis of arthritis. Kappa coefficient showed slight to fair agreement of 0.19–0.32 between self-report and administrative database definitions of arthritis. We found significantly higher overall discordance among veterans with more comorbidities, greater age, worse functional status, lower use of outpatient and inpatient services, lower education level, and among single medical-site users.

Conclusion.

Low level of agreement between self-report and database diagnosis of arthritis and its significant association with patient demographic, clinical, and functional characteristics highlights the limitation of use of these strategies for identification of patients with arthritis in epidemiological studies.

Impact of androgen deprivation therapy on cardiovascular disease and diabetes

PURPOSE Use of androgen deprivation therapy (ADT) may be associated with an increased risk of diabetes mellitus but the risk of both acute myocardial infarction (AMI) and cardiovascular mortality remain controversial because few outcomes and conflicting findings have been reported. We sought to clarify whether ADT is associated with these outcomes in a large, representative cohort. METHODS Using linked administrative databases in Ontario, Canada, men age 66 years or older with prostate cancer given continuous ADT for at least 6 months or who underwent bilateral orchiectomy (n = 19,079) were matched with men with prostate cancer who had never received ADT. Treated and untreated groups were matched 1:1 (ie, hard-matched) on age, prior cancer treatment, and year of diagnosis and propensity-matched on comorbidities, medications, cardiovascular risk factors, prior fractures, and socioeconomic variables. Primary outcomes were development of AMI, sudden cardiac death, and diabetes. Fragility fracture was also examined. Results The cohort was observed for a mean of 6.47 years. In time-to-event analyses, ADT use was associated with an increased risk of diabetes (hazard ratio [HR], 1.16; 95% CI, 1.11 to 1.21) and fragility fracture (HR, 1.65; 95% CI, 1.53 to 1.77) but not with AMI (HR, 0.91; 95% CI, 0.84 to 1.00) or sudden cardiac death (HR, 0.96; 95% CI, 0.83 to 1.10). Increasing duration of ADT was associated with an excess risk of fragility fractures and diabetes but not cardiac outcomes. CONCLUSION Continuous ADT use for at least 6 months in older men is associated with an increased risk of diabetes and fragility fracture but not AMI or sudden cardiac death.

Low-density lipoprotein reduction and magnitude of cardiovascular risk reduction

The authors examined the relationship between the magnitude of low-density lipoprotein cholesterol (LDL-C) reduction and the magnitude of cardiovascular risk reduction. From the Veterans Integrated Service Network 1 databases, the authors selected 54,611 patients with prevalent ischemic heart disease, peripheral vascular disease or diabetes mellitus, and >or=2 documented LDL-C levels who were followed between 1997 and 2006. The outcome was defined as acute myocardial infarction or revascularization. Preoutcome LDL-C reduction was categorized as follows: <10 mg/dL, reference; >or=10 but <40 mg/dL, small reduction; >or=40 but <70 mg/dL, moderate reduction; >or=70 mg/dL, large reduction. Proportional hazards were used to determine the hazard ratio for the outcome for each LDL-C reduction category compared with the reference. Results revealed a graded relationship between the magnitude of reduction in LDL-C and cardiovascular risk reduction. Stratified analyses demonstrated these findings to be robust regardless of initial LDL-C levels or whether patients achieved "target" final LDL-C values of <100 mg/dL.

Depression increases risk of incident myocardial infarction among Veterans Administration patients with rheumatoid arthritis

OBJECTIVE

This study evaluates whether depression is a risk factor for incident myocardial infarction (MI) in Department of Veterans Affairs (VA) patients with rheumatoid arthritis (RA) between 30 and 79 years of age.

METHODS

We used a retrospective cohort study of 15,634 patients with RA. Diagnoses and sociodemographic data were obtained from VA administrative and pharmacy databases between fiscal years 1999 and 2006. Entry into the cohort required 2 years of patient time with no evidence of cardiovascular disease. Cox proportional hazard models with time-dependent covariates were computed to determine whether RA patients with depression as compared to RA patients without depression were at increased risk for MI during the maximum 6-year follow-up period.

RESULTS

Unadjusted analyses indicated depressed RA patients were 1.4 times more likely than nondepressed RA patients to have an MI during follow-up. These results remained significant (HR=1.4; 95% CI: 1.1-1.8) in the adjusted Cox proportional hazards model which included the effects of sociodemographics and known physical risks (e.g., diabetes) for MI.

CONCLUSIONS

Depressed RA patients, without a history of cardiovascular disease, are 40% more likely to have a heart attack as compared to those without depression. These data demonstrate a rapid (within 6 years) transition to MI following onset of depression in RA patients. Increased monitoring of depression and heart disease status in this patient population may be warranted which in turn may result in longer duration of life.

Mortality risk of Charcot arthropathy compared with that of diabetic foot ulcer and diabetes alone

OBJECTIVE

The purpose of this study was to compare mortality risks of patients with Charcot arthropathy with those of patients with diabetic foot ulcer and those of patients with diabetes alone (no ulcer or Charcot arthropathy).

RESEARCH DESIGN AND METHODS

A retrospective cohort of 1,050 patients with incident Charcot arthropathy in 2003 in a large health care system was compared with patients with foot ulcer and those with diabetes alone. Mortality was determined during a 5-year follow-up period. Patients with Charcot arthropathy were matched to individuals in the other two groups using propensity score matching based on patient age, sex, race, marital status, diabetes duration, and diabetes control.

RESULTS

During follow-up, 28.0% of the sample died; 18.8% with diabetes alone and 37.0% with foot ulcer died compared with 28.3% with Charcot arthropathy. Multivariable Cox regression shows that, compared with Charcot arthropathy, foot ulcer was associated with 35% higher mortality risk (hazard ratio 1.35 [95% CI 1.18-1.54]) and diabetes alone with 23% lower risk (0.77 [0.66-0.90]). Of the patients with Charcot arthropathy, 63% experienced foot ulceration before or after the onset of the Charcot arthropathy. Stratified analyses suggest that Charcot arthropathy is associated with a significantly increased mortality risk independent of foot ulcer and other comorbidities.

CONCLUSIONS

Charcot arthropathy was significantly associated with higher mortality risk than diabetes alone and with lower risk than foot ulcer. Patients with foot ulcers tended to have a higher prevalence of peripheral vascular disease and macrovascular diseases than patients with Charcot arthropathy. This finding may explain the difference in mortality risks between the two groups.

Risk of acute myocardial infarction in patients treated with thiazolidinediones or other antidiabetic medications

PURPOSE

Controversy surrounds the question whether thiazolidinediones (TZDs) increase the risk of acute myocardial infarction (AMI). This study examined risk of AMI in patients with type 2 diabetes mellitus (T2DM) who were taking TZDs or other antidiabetic medications.

METHODS

Using a nested case-control design, a cohort of patients aged 18-84 years with T2DM and use of an oral antidiabetic medication or exenatide between January 2002 and June 2006 was identified. Cases of AMI were matched with up to four controls based on age, gender, health plan, geography, and diabetes therapy regimen. Over the 1-year pre-index period, TZD exposure was compared with no TZD exposure, after adjustment for potential confounders.

RESULTS

Overall, 1681 cases were identified and matched with 6653 controls. Compared with no TZD exposure, an increased risk of AMI was not observed among TZD exposed patients (adjusted OR 1.01; 95%CI, 0.85-1.20; adjusted p = 0.98). When exposure proximity to the event was examined, the risk of AMI was significantly increased with recent rosiglitazone exposure between 1 and 60 days prior to the case date (adjusted OR 1.69; 95%CI, 1.18-2.44; adjusted p = 0.045) and was not significantly increased with current or remote rosiglitazone exposure or current, recent, or remote pioglitazone exposure.

CONCLUSION

TZD exposure did not increase the risk of AMI when exposure proximity was not considered. However, when evaluating exposure proximity to the event, the risk of AMI was increased with recent rosiglitazone exposure between 1 and 60 days prior to the case date.

Coronary heart disease attributable to passive smoking: CHD Policy Model

BACKGROUND

Passive smoking is a major risk factor for coronary heart disease (CHD), and existing estimates are out of date due to recent and substantial changes in the level of exposure.

OBJECTIVE

To estimate the annual clinical burden and cost of CHD treatment attributable to passive smoking.

OUTCOME MEASURES

Annual attributable CHD deaths, myocardial infarctions (MI), total CHD events, and the direct cost of CHD treatment.

METHODS

A Monte Carlo simulation estimated the CHD events and costs as a function of the prevalence of CHD risk factors, including passive-smoking prevalence and a low (1.26) and high (1.65) relative risk of CHD due to passive smoking. Estimates were calculated using the CHD Policy Model, calibrated to reproduce key CHD outcomes in the baseline Year 2000 in the U.S.

RESULTS

At 1999-2004 levels, passive smoking caused 21,800 (SE=2400) to 75,100 (SE=8000) CHD deaths and 38,100 (SE=4300) to 128,900 (SE=14,000) MIs annually, with a yearly CHD treatment cost of $1.8 (SE=$0.2) to $6.0 (SE=$0.7) billion. If recent trends in the reduction in the prevalence of passive smoking continue from 2000 to 2008, the burden would be reduced by approximately 25%-30%.

CONCLUSIONS

Passive smoking remains a substantial clinical and economic burden in the U.S.

Health-related quality of life in veterans with prevalent total knee arthroplasty and total hip arthroplasty

OBJECTIVE

To study the HRQOL in veterans with prevalent total knee arthroplasty (TKA) or total hip arthroplasty (THA) and compare them with age- and gender-matched US population and control veteran population without these procedures.

METHODS

A cohort study and cross-sectional survey on veterans obtained demographics and HRQOL with Short-Form 36 for veterans (SF-36V). Veterans were categorized into: primary TKA; primary THA; combination group (>/=1 primary and/or any revision TKA/THA); and control population (no THA/TKA). Multivariable regression compared the physical and mental component summary scores (PCS and MCS scores, respectively) in each group.

RESULTS

Response rate was 58% (40 508/70 334): 531 with TKA, 254 with THA, 461 constituted the combination and 39 262, the control group. Mean PCS scores in veterans with THA, TKA, and combination group were 2 s.d. lower than the US mean (29.5 +/- 0.8; 30.1 +/- 1.1 and 27.1 +/- 0.8). MCS scores were similar to the US mean (47.3 +/- 0.9; 49.1 +/- 1.2 and 45.6 +/- 0.9). Compared with controls, significantly more veterans in TKA, THA or combination groups had multivariable-adjusted PCS /= 0.01) were statistically and clinically lower.

CONCLUSIONS

Profound physical HRQOL deficits exist in veterans with TKA/THA and in combination group compared with age- and gender-matched general US population and with veteran controls. In these groups, these deficits are not attributable to differences in sociodemographics, comorbidity and healthcare access/utilization. Arthroplasty status may be a surrogate for poorer HRQOL and worse outcomes. Future studies are indicated to determine HRQOL deficit causes and interventions to improve HRQOL in patients with arthroplasty.

Identification of Helicobacter pylori infected patients, using administrative data

BACKGROUND

Helicobacter pylori is a prevalent organism implicated in peptic ulcer disease.

AIM

To validate administrative data for diagnosis of H. pylori-infected patients.

METHODS

Administrative data identified patients with ICD-9 code for H. pylori (041.86) or prescription of eradication therapy; diagnosis was confirmed by chart abstraction. Multivariable regression assessed predictors of infection considering drug therapy, ICD-9 code 041.86, procedure code, in-patient or out-patient diagnostic code, age, gender and race to generate an algorithm for validation.

RESULTS

The test cohort of 531 patients (361 potential cases; 170 random controls) was primarily male (94%), Caucasian (59%) and elderly [67 years (s.d. 10)]. The positive predictive value (PPV) of ICD-9 code 041.86 was 100% and 97.4% if from an in-patient or out-patient encounter, respectively. Eradication drug therapy had a PPV of 73.7% (triple therapy) and 97.7% (quadruple therapy). The strongest predictors were out-patient ICD-9 code 041.86 (OR 8.1; 95% CI: 7.0-9.1); eradication drug therapy (OR 7.4; 95% CI: 6.6-8.3); oesophagogastroduodenoscopy (OR 3.5; 95% CI: 3.3-3.6); and age > or =70 (OR 1.2; 95% CI: 1.1-1.4). An algorithm including these data elements yielded a c-statistic of 0.93 and PPV of 97.9%.

CONCLUSIONS

Administrative data can diagnose H. pylori-infected patients. The diagnostic algorithm includes presence of eradication drug therapy overlapping with an out-patient ICD-9 code 041.86 among elderly adults.

Gout is associated with more comorbidities, poorer health-related quality of life and higher healthcare utilisation in US veterans

OBJECTIVE

To better understand the impact of gout on functional status, health-related quality of life (HRQoL), mortality and healthcare utilisation in US veterans.

METHODS

All veterans seen in Veterans Integrated Service Network-13 from 1 October 1996 to 31 March 1998 received mailed surveys asking about demographic characteristics; performance of activities of daily living and HRQoL by Short Form-36 (SF-36) for Veterans. Administrative data included demographics; inpatient/outpatient healthcare utilisation; ICD-9 codes for gout, medical comorbidities and arthritis excluding gout-"arthritic comorbidity" and 1-year mortality. Multivariable estimates compared results between veterans with/without gout using least means squared.

RESULTS

SUBJECTS

with gout were significantly older, retired, not married, current non-smokers, with more comorbidities. Multivariable-adjusted bodily pain was somewhat worse (49.7 vs 47.1, p<0.01) and mental health (66.7 vs 68.6, p<0.01) domain scores somewhat better in patients with gout, both differences significant but not clinically meaningful (less than threshold of 5-10 points); other SF-36 domain and summary scores and functional limitations were similar. Medical or arthritic comorbidities predicted clinically/statistically lower adjusted scores in all SF-36 domains and physical domains (physical component summary), respectively. Patients with gout had significantly more annual primary care visits (3.5 vs 2.7, p<0.001) and admissions to hospital (18.3% vs 15.1%, p<0.01), fewer mental health visits (10.1% vs 13.7%, p<0.01) and similar mortality (2.6% vs 2.2%, p = 0.23).

CONCLUSIONS

Gout is independently associated with higher medical and arthritic comorbidity, primary care and inpatient utilisation. Poorer HRQoL, functional limitation and higher mortality noted in univariate analyses in patients with gout were attributable to higher comorbidity and sociodemographic characteristics.

Rationale and design of the Post-MI FREEE trial: a randomized evaluation of first-dollar drug coverage for post-myocardial infarction secondary preventive therapies

BACKGROUND

Medication nonadherence is a major public health problem, especially for patients with coronary artery disease. The cost of prescription drugs is a central reason for nonadherence, even for patients with drug insurance. Removing patient out-of-pocket drug costs may increase adherence, improve clinical outcomes, and even reduce overall health costs for high-risk patients. The existing data are inadequate to assess whether this strategy is effective.

TRIAL DESIGN

The Post-Myocardial Infarction Free Rx and Economic Evaluation (Post-MI FREEE) trial aims to evaluate the effect of providing full prescription drug coverage (ie, no copays, coinsurance, or deductibles) for statins, beta-blockers, angiotensin-converting enzyme inhibitors, and angiotensin II receptor blockers to patients after being recently discharged from the hospital. Potentially eligible patients will be those individuals who receive their health and pharmacy benefits through Aetna, Inc. Patients enrolled in a Health Savings Account plan, who are > or =65 years of age, whose plan sponsor (ie, the employer, union, government, or association that sponsors the particular benefits package) has opted out of participating in the study, and who do not receive both medical services and pharmacy coverage through Aetna will be excluded. The plan sponsor of each eligible patient will be block randomized to either full drug coverage or current levels of pharmacy benefit, and all subsequently eligible patients of that same plan sponsor will be assigned to the same benefits group. The primary outcome of the trial is a composite clinical outcome of readmission for acute MI, unstable angina, stroke, congestive heart failure, revascularization, or inhospital cardiovascular death. Secondary outcomes include medication adherence and health care costs. All patients will be followed up for a minimum of 1 year.

CONCLUSION

The Post-MI FREEE trial will be the first randomized study to evaluate the impact of reducing cost-sharing for essential cardiac medications in high-risk patients on clinical and economic outcomes.

National mortality following upper gastrointestinal or cardiovascular events in older veterans with recent nonsteroidal anti-inflammatory drug use

BACKGROUND

Upper gastrointestinal events (UGIE), myocardial infarction (MI) and cerebrovascular accident (CVA) are known morbidities among recent NSAID users.

AIM

To assess all-cause mortality following UGIE, MI or CVA among recent NSAID users.

METHODS

Veterans >65 prescribed an NSAID at any Veterans Affairs (VA) facility were identified using prescription fill data and their records linked to a merged VA-Medicare database. Each person-day was assessed for NSAID, coxib or proton pump inhibitor (PPI) exposure. Incidence density ratios and hazard rates of death were calculated following UGIE, MI and CVA adjusting for demographics, co-morbidity, prescription channeling, geographic location and pharmacological covariates.

RESULTS

Among 474 495 patients [97.8% male; 85.3% white; 73.9 years (s.d. 5.6)], death followed at a rate of 5.5 per 1000 person-years (95% CI: 5.4-5.6) post-UGIE, 17.7 per 1000 person-years (95% CI: 17.5-17.9) post-MI and 21.8 per 1000 person-years (95% CI: 21.6-22.0) post-CVA. CVA was associated with greatest risk of death [hazard ratio (HR) 12.4; 95% CI: 10.9-14.3] followed by MI (HR 10.7; 95% CI: 9.2-11.6) and UGIE (HR 3.3; 95% CI: 2.8-3.9). Predictors of mortality were advancing age and co-morbidity, increased use of coxibs and failure to ensure adequate gastroprotection.

CONCLUSION

Among elderly veterans with recent NSAID use, an UGIE, MI or CVA is a clinically relevant premorbid event.

Feasibility of determining myocardial infarction type from medical record review

BACKGROUND

Hospital discharge data are used extensively in health research. Given the clinical differences between ST segment elevation myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI), it is important that these entities be distinguishable in a medical record. The authors sought to determine the extent to which the type of MI is recorded in medical records, as well as the consistency of this designation within individual records.

METHODS

Records of all MI patients admitted to a tertiary care centre in Canada from April 1, 2000, to March 31, 2001, were reviewed. Documentation and consistency of the use of the terms STEMI (Q wave, ST elevation or transmural MI) or NSTEMI (non-Q wave, subendocardial or nontransmural MI) were assessed in the admission history, progress notes, coronary care unit summary and discharge summary sections of each record.

RESULTS

Missing data were common; each chart section mentioned MI type in fewer than one-half of charts. When information was combined, it was possible to determine the type of MI in 81.1% of cases. MI type was consistently described as STEMI in 48.7% of cases, and as NSTEMI in 32.4%. Of concern, MI type was discrepant across sections in 10.5% of cases and missing entirely in 8.4% of cases.

CONCLUSIONS

The designation of MI cases as STEMI or NSTEMI is both incomplete and inconsistent in hospital records. This has implications for health services research conducted retrospectively using medical record data, because it is difficult to comprehensively study processes and outcomes of MI care if the type cannot be retrospectively determined.

The validity of viral hepatitis and chronic liver disease diagnoses in Veterans Affairs administrative databases

BACKGROUND

The validity of International Classification of Diseases-9 codes for liver disease has not been determined.

AIM

To examine the accuracy of International Classification of Diseases-9 codes for cirrhosis with hepatitis C virus or alcoholic liver disease and HIV or hepatitis B virus coinfection with hepatitis C virus in Veterans Affairs data.

METHODS

We conducted a retrospective study comparing the Veterans Affairs administrative data with abstracted data from the Michael E. DeBakey VA Medical Center's medical records. We calculated the positive predictive value, negative predictive value, per cent agreement and kappa.

RESULTS

For cirrhosis codes, the positive predictive value (probability that cirrhosis is present among those with a code) and negative predictive value (probability that cirrhosis is absent among those without a code) were 90% and 87% with 88% agreement and kappa = 0.70. For hepatitis C virus codes, the positive predictive value and negative predictive value were 93% and 92%, yielding 92% agreement and kappa = 0.78. For alcoholic liver disease codes, the positive predictive value and negative predictive value were 71% and 98%, with 89% agreement and kappa = 0.74. All parameters for HIV coinfection with hepatitis C virus were >89%; however, the codes for hepatitis B virus coinfection had a positive predictive value of 43-67%.

CONCLUSION

These diagnostic codes (except hepatitis B virus) in Veterans Affairs administrative data are highly predictive of the presence of these conditions in medical records and can be reliably used for research.