An algorithm to identify incident myocardial infarction using Medicaid data

Cardiovascular and renal outcomes of GLP-1 receptor agonists vs. DPP-4 inhibitors and basal insulin in type 2 diabetes mellitus: A systematic review and meta-analysis

OBJECTIVE

To compare the cardiovascular and renal outcomes of GLP-1 RA versus DPP4i and basal insulin in the management of T2DM.

METHODS

Data from 22 studies involving over 200,000 participants were pooled using the inverse variance method and random-effects meta-analysis. The review was reported in accordance with PRISMA.

RESULTS

Compared with DPP4i, treatment with GLP-1 RA was associated with a greater benefit on composite cardiovascular outcomes (HR:0.77, 95% CI:0.69-0.87), myocardial infarction (HR:0.82, 95% CI:0.69-0.97), stroke (HR:0.83, 95% CI: 0.74-0.93), cardiovascular mortality (HR:0.76, 95% CI:0.68-0.85) and all-cause mortality (HR:0.65, 95% CI:0.48-0.90). There was no difference in effect on heart failure (HR:0.97, 95% CI:0.82-1.15). Compared with basal insulin, GLP-1 RA was associated with better effects on composite cardiovascular outcomes (HR:0.62, 95% CI:0.48-0.79), heart failure (HR:0.57, 95% CI:0.35-0.92), myocardial infarction (HR:0.70, 95% CI:0.58-0.85), stroke (HR:0.50, 95% CI:0.40-0.63) and all-cause mortality (HR:0.31, 95% CI:0.20-0.48). Evidence from a small number of studies suggests that GLP-1 RA had better effects on composite and individual renal outcomes, such as eGFR, compared with either DPP4i and basal insulin.

CONCLUSION

Available evidence suggests that treating T2DM with GLP-1 RA can yield better benefits on composite and specific cardiorenal outcomes than with DPP4i and basal insulin.

PROSPERO REGISTRATION NUMBER

CRD42022335504.

Duloxetine, Gabapentin, and the Risk for Acute Myocardial Infarction, Stroke, and Out-of-Hospital Death in Medicare Beneficiaries With Non-Cancer Pain

OBJECTIVE

Duloxetine is a serotonin-norepinephrine reuptake inhibitor prescribed for musculoskeletal and other forms of chronic pain. Its dual pharmacologic properties have the potential to either raise or lower cardiovascular risk: adrenergic activity may increase the risk for acute myocardial infarction (AMI) and stroke, but antiplatelet activity may decrease risk. Gabapentin is another nonopioid medication used to treat pain, which is not thought to have adrenergic/antiplatelet effects. With the current emphasis on the use of nonopioid medications to treat patients with chronic pain, assessing cardiovascular risks associated with these medications among high-risk patients is important.

MATERIALS AND METHODS

We conducted a retrospective cohort study among a 20% sample of Medicare enrollees, aged 65 to 89, with chronic pain who were new users between 2015 and 2018 of either duloxetine (n = 34,009) or gabapentin (n = 233,060). We excluded individuals with cancer or other life-threatening conditions at study drug initiation. The primary outcome was a composite of AMI, stroke, and out-of-hospital mortality. We adjusted for comorbidity differences with time-dependent inverse probability of treatment weighting.

RESULTS

During 115,668 person-years of follow-up, 2361 patients had the composite primary outcome; the rate among new users of duloxetine was 16.7/1000 person-years compared with new users of gabapentin (21.1/1000 person-years), adjusted hazard ratio = 0.98 (95% CI: 0.83, 1.16). Results were similar for the individual components of the composite outcome as well as in analyses stratified by demographic and clinical characteristics.

DISCUSSION

In summary, cohort Medicare patients with non-cancer pain beginning treatment with duloxetine had rates of AMI, stroke, and out-of-hospital mortality comparable to those who initiated gabapentin.

Comparative safety of sulfonylureas among U.S. nursing home residents

BACKGROUND

The comparative safety of sulfonylureas (SUs) in nursing home (NH) residents remains understudied despite widespread use. We compared the effects of three SU medications and initial SU doses on adverse glycemic and cardiovascular events among NH residents.

METHODS

This national retrospective cohort study linked Medicare claims with Minimum Data Set 2.0 assessments for long-stay NH residents aged ≥65 years between January 2008 and September 2010. Exposures were the SU medication initiated (glimepiride, glipizide, or glyburide) and doses (standard or reduced). One-year outcomes were hospitalizations or emergency department visits for severe hypoglycemia, heart failure (HF), stroke, and acute myocardial infarction (AMI). After the inverse probability of treatment and inverse probability of censoring by death weighting, we estimated hazard ratios (HR) using Cox regression models with robust 95% confidence intervals (CI).

RESULTS

The cohort (N = 6821) included 3698 new glipizide, 1754 glimepiride, and 1369 glyburide users. Overall, the mean (standard deviation) age was 81.4 (8.2) years, 4816 (70.6%) were female, and 5164 (75.7%) were White non-Hispanic residents. The rates of severe hypoglycemia were 30.3 (95% CI 22.3-40.1), 49.0 (95% CI 34.5-67.5), and 35.9 (95% CI 22.2-54.9) events per 1000 person-years among new glipizide, glimepiride, and glyburide users, respectively (glimepiride versus glipizide HR 1.6, 95% CI 1.0-2.4, p = 0.04; glyburide versus glipizide HR 1.2, 95% CI 0.7-1.9, p = 0.59). The rates of severe hypoglycemia were 27.1 (95% CI 18.6-38.0) and 42.8 (95% CI 33.6-53.8) events per 1000 person-years among new users of reduced and standard SU doses, respectively (HR 2.2, 95% CI 1.4-3.5, p < 0.01). Rates of HF, stroke, and AMI were similar between medications and doses.

CONCLUSIONS

Among long-stay NH residents, new use of glimepiride and standard SU doses resulted in higher rates of severe hypoglycemic events. Cardiovascular outcomes may not be affected by the choice of SU medication or dose.

PheValuator 2.0: Methodological improvements for the PheValuator approach to semi-automated phenotype algorithm evaluation

PURPOSE

Phenotype algorithms are central to performing analyses using observational data. These algorithms translate the clinical idea of a health condition into an executable set of rules allowing for queries of data elements from a database. PheValuator, a software package in the Observational Health Data Sciences and Informatics (OHDSI) tool stack, provides a method to assess the performance characteristics of these algorithms, namely, sensitivity, specificity, and positive and negative predictive value. It uses machine learning to develop predictive models for determining a probabilistic gold standard of subjects for assessment of cases and non-cases of health conditions. PheValuator was developed to complement or even replace the traditional approach of algorithm validation, i.e., by expert assessment of subject records through chart review. Results in our first PheValuator paper suggest a systematic underestimation of the PPV compared to previous results using chart review. In this paper we evaluate modifications made to the method designed to improve its performance.

METHODS

The major changes to PheValuator included allowing all diagnostic conditions, clinical observations, drug prescriptions, and laboratory measurements to be included as predictors within the modeling process whereas in the prior version there were significant restrictions on the included predictors. We also have allowed for the inclusion of the temporal relationships of the predictors in the model. To evaluate the performance of the new method, we compared the results from the new and original methods against results found from the literature using traditional validation of algorithms for 19 phenotypes. We performed these tests using data from five commercial databases.

RESULTS

In the assessment aggregating all phenotype algorithms, the median difference between the PheValuator estimate and the gold standard estimate for PPV was reduced from -21 (IQR -34, -3) in Version 1.0 to 4 (IQR -3, 15) using Version 2.0. We found a median difference in specificity of 3 (IQR 1, 4.25) for Version 1.0 and 3 (IQR 1, 4) for Version 2.0. The median difference between the two versions of PheValuator and the gold standard for estimates of sensitivity was reduced from -39 (-51, -20) to -16 (-34, -6).

CONCLUSION

PheValuator 2.0 produces estimates for the performance characteristics for phenotype algorithms that are significantly closer to estimates from traditional validation through chart review compared to version 1.0. With this tool in researcher's toolkits, methods, such as quantitative bias analysis, may now be used to improve the reliability and reproducibility of research studies using observational data.

Cardiovascular risk associated with allopurinol vs. benzbromarone in patients with gout

Aims 

With the high prevalence of gout and associated cardiovascular (CV) diseases, information on the comparative CV safety of individual urate-lowering drugs becomes increasingly important. However, few studies examined the CV risk of uricosuric agents. We compared CV risk among patients with gout who initiated allopurinol vs. benzbromarone.

Methods and results 

Using the Korean National Health Insurance claims data (2002–17), we conducted a cohort study of 124 434 gout patients who initiated either allopurinol (n = 103 695) or benzbromarone (n = 20 739), matched on propensity score at a 5:1 ratio. The primary outcome was a composite CV endpoint of myocardial infarction, stroke/transient ischaemic attack, or coronary revascularization. To account for competing risk of death, we used cause-specific hazard models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the outcomes comparing allopurinol initiators with benzbromarone. Over a mean follow-up of 1.16 years, 2258 patients developed a composite CV event. The incidence rate of the composite CV event was higher in allopurinol initiators (1.81 per 100 person-years) than benzbromarone (1.61 per 100 person-years) with a HR of 1.22 (95% CI 1.05–1.41). The HR for all-cause mortality was 1.66 (95% CI 1.43–1.93) among allopurinol initiators compared with benzbromarone.

Conclusion 

In this large population-based cohort of gout patients, allopurinol was associated with an increased risk of composite CV events and all-cause mortality compared to benzbromarone. Benzbromarone may reduce CV risk and mortality in patients with gout, although more studies are necessary to confirm our findings and to advance our understanding of the underlying mechanisms.

Long-term safety of extended levonorgestrel-containing oral contraceptives in the United States

OBJECTIVES

To compare the safety profile of Seasonique, a 91-day levonorgestrel-containing combined oral contraceptive (COC_LNG), to 28-day COC_LNG regarding the risk of venous thromboembolism (VTE) and arterial thromboembolism (ATE).

STUDY DESIGN

A new user cohort study was conducted in a US health care database from 2006 to 2017. Each 91-day COC_LNG treatment episode in females was matched to up to four 28-day COC_LNG treatment episodes by propensity score. We identified VTE cases in either (1) an inpatient setting with ICD-9 and ICD-10 diagnosis codes of PE and/or DVT in the primary position, or (2) an outpatient setting with ICD-9 or ICD-10 diagnosis codes of DVT in conjunction with an anticoagulant medication dispensing or alteplase (thrombolytic) during the 30-day period following the date of DVT diagnosis. VTE was validated using medical records. We assessed the study endpoints in the two cohorts using incidence rates and Cox proportional hazards models adjusted for potential confounders.

RESULTS

Of the 25,593 treatment episodes in 91-day COC_LNG and 76,586 treatment episodes in 28-day COC_LNG, 35 and 68 patients had VTEs, respectively, corresponding to a hazard ratio (HR) of 1.40 (95% confidence interval [CI], 0.90-2.19). The VTE algorithm had a positive predictive value of 76.4% (95% CI, 66.2%-84.8%). ATEs were recorded in 13 and 28 episodes, respectively, with a corresponding HR of 1.21 (95% CI, 0.58-2.53).

CONCLUSIONS

These results do not indicate a significant difference between 91-day COC_LNG and 28-day COC_LNG in terms of VTE or ATE risk.

IMPLICATIONS

Compared to use of 28-day COC_LNG, use of 91-day extended COC_LNG was not associated with a significant difference in risk of venous and arterial thromboembolism.

Trends in the Inpatient Burden of Coronary Artery Disease in Granulomatosis With Polyangiitis: A Study of a Large National Dataset

OBJECTIVE

Cardiovascular (CV) diseases are serious comorbidities in patients with granulomatosis with polyangiitis (GPA). In a sample of patients hospitalized for GPA, we sought to examine trends in the burden of coronary artery disease (CAD) and its 2 serious manifestations, acute myocardial infarction (AMI) and heart failure (HF).

METHODS

We used the National Inpatient Sample to conduct a retrospective cross-sectional analysis. Our sample consisted of hospitalizations for GPA between 2005 and 2014. We examined trends in the proportion of CAD, AMI, and HF in all hospitalizations with GPA compared to those without GPA. We used logistic regression adjusted for potential confounders and included interaction terms.

RESULTS

Among a total of 103,453 GPA hospitalizations, 20,351 (19.7%) hospitalizations had a concurrent diagnosis of CAD. GPA with CAD was associated with overall lower burden of traditional CV risk factors compared to non-GPA with CAD, with the exception of chronic kidney disease (57% vs 21%). Over the 10-year study period, there were rising trends in the inpatient burden of CAD (16.6% in 2005 to 22.7% in 2014) and CAD with HF (4.3% in 2005 to 9.9% in 2014), but not AMI (1.2% in 2005 to 1.1% in 2014), in GPA hospitalizations compared to non-GPA controls.

CONCLUSION

In this national sample of GPA hospitalizations, we found that the burden of CAD and CAD with HF was on the rise over the 10-year period compared to non-GPA; however, it was not the case for AMI.

Comparative cardiovascular risk of allopurinol versus febuxostat in patients with gout: a nation-wide cohort study

OBJECTIVE

To compare cardiovascular (CV) risk among gout patients initiating allopurinol vs febuxostat.

METHODS

Using 2002-2015 Korean National Health Insurance Service data for the entire Korean population, we conducted a cohort study on gout patients initiating allopurinol or febuxostat. The primary outcome was a composite CV end point of myocardial infarction, stroke/transient ischaemic attack, or coronary revascularization. Secondary outcomes were individual components of the primary outcome, and all-cause mortality. We used propensity score-matching with a 4:1 ratio for allopurinol and febuxostat initiators to control for confounding. Competing risk analyses were done for non-fatal outcomes accounting for deaths.

RESULTS

We included 39 640 allopurinol initiators propensity score-matched on 9910 febuxostat initiators. The mean age was 59.1 years and 78.4% were male. The incidence rate per 100 person-years for the primary outcome was 1.89 for allopurinol and 1.84 for febuxostat initiators. The corresponding hazard ratio comparing allopurinol vs febuxostat initiators was 1.09 (95% CI: 0.90, 1.32). No significant difference was found for the secondary outcomes, including all-cause mortality (hazard ratio 0.96; 95% CI: 0.79, 1.16). Subgroup analyses limited to those at high CV risk and to equipotent-dose initiators (i.e. allopurinol ⩾300 mg/day vs febuxostat ⩾40 mg/day) showed similar results.

CONCLUSION

Overall, this large Korean population-based study suggests no difference in the risk of non-fatal CV events and all-cause mortality between allopurinol and febuxostat initiators. These findings are consistent with the recent US Medicare population study, although the current study population consisted of younger Asians.

Psychostimulants/Atomoxetine and Serious Cardiovascular Events in Children with ADHD or Autism Spectrum Disorder

BACKGROUND

Psychostimulants and atomoxetine have been shown to increase blood pressure, heart rate, and QT interval in children and adolescents; however, based on current literature, it is unclear if these "attention-deficit/hyperactivity disorder (ADHD) medications" are also associated with serious cardiovascular (SCV) events. We addressed this question in commonly exposed groups of children and adolescents with either ADHD or autism spectrum disorder (ASD).

METHODS

Using commercial (years 2000-2016) and Medicaid (years 2012-2016) administrative claims data from the United States (US), we conducted two case-control studies, nested within respective cohorts of ADHD and ASD children aged 3-18 years. We defined cases by a composite outcome of stroke, myocardial infarction, or serious cardiac arrhythmia. For each case, we matched ten controls on age, sex, and insurance type. We conducted conditional logistic regression models to test associations between SCV outcomes and a primary exposure definition of current ADHD medication use. Additionally, we controlled for resource use, cardiovascular and psychiatric comorbidities, and use of medications in a variety of sensitivity analyses.

RESULTS

We identified 2,240,774 children for the ADHD cohort and 326,221 children for the ASD cohort. For ADHD, 33.9% of cases (63 of 186) versus 32.2% of controls (598 of 1860) were exposed, which yielded an odds ratio (OR) and 95% confidence interval (CI) of 1.08 (0.78-1.49). For ASD, 12.5% of cases (6 of 48) versus 22.1% of controls (106 of 480) were exposed [OR 0.49 (0.20-1.20)]. Covariate-adjusted results and results for individual outcomes and other exposure definitions were consistent with no increased risk of SCV events.

CONCLUSION

Using large US claims data, we found no evidence of increased SCV risk in children and adolescents with ADHD or ASD exposed to ADHD medications.

PheValuator: Development and evaluation of a phenotype algorithm evaluator

BACKGROUND

The primary approach for defining disease in observational healthcare databases is to construct phenotype algorithms (PAs), rule-based heuristics predicated on the presence, absence, and temporal logic of clinical observations. However, a complete evaluation of PAs, i.e., determining sensitivity, specificity, and positive predictive value (PPV), is rarely performed. In this study, we propose a tool (PheValuator) to efficiently estimate a complete PA evaluation.

METHODS

We used 4 administrative claims datasets: OptumInsight's de-identified Clinformatics™ Datamart (Eden Prairie,MN); IBM MarketScan Multi-State Medicaid); IBM MarketScan Medicare Supplemental Beneficiaries; and IBM MarketScan Commercial Claims and Encounters from 2000 to 2017. Using PheValuator involves (1) creating a diagnostic predictive model for the phenotype, (2) applying the model to a large set of randomly selected subjects, and (3) comparing each subject's predicted probability for the phenotype to inclusion/exclusion in PAs. We used the predictions as a 'probabilistic gold standard' measure to classify positive/negative cases. We examined 4 phenotypes: myocardial infarction, cerebral infarction, chronic kidney disease, and atrial fibrillation. We examined several PAs for each phenotype including 1-time (1X) occurrence of the diagnosis code in the subject's record and 1-time occurrence of the diagnosis in an inpatient setting with the diagnosis code as the primary reason for admission (1X-IP-1stPos).

RESULTS

Across phenotypes, the 1X PA showed the highest sensitivity/lowest PPV among all PAs. 1X-IP-1stPos yielded the highest PPV/lowest sensitivity. Specificity was very high across algorithms. We found similar results between algorithms across datasets.

CONCLUSION

PheValuator appears to show promise as a tool to estimate PA performance characteristics.

Modafinil and the risk of cardiovascular events: Findings from three US claims databases

PURPOSE

This study examined the potential risk of cardiovascular (CV) events associated with modafinil and the consistency of the risk estimates across databases.

METHODS

A retrospective, inception cohort design of patients who initiated treatment with modafinil between 2006 and 2008 was used in three US health care claims databases. Modafinil users were matched with nonusers. Patients were further divided into two cohorts of obstructive sleep apnea (OSA) and non-OSA (NOSA) cohorts. Endpoints of interest, including myocardial infarction (MI), stroke, CV hospitalizations, and all-cause death, were assessed using incidence rates and Cox proportional hazard ratios (HRs), adjusted for potential confounding factors.

RESULTS

The cohorts included a total of 175 524 patients in MarketScan CM; 77 266-in IMS LifeLink; and 8174-in MarketScan Medicaid. No increased risk for MI in the OSA and NOSA cohorts was observed across all three databases. The risks of CV hospitalization in the OSA and NOSA cohorts were not different between the modafinil users and nonusers, except for IMS LifeLink database where the HR was lower than one in the modafinil users compared with the nonusers (HR, 0.69; 95% confidence interval [CI], 0.54 to 0.87). For OSA patients with prior stroke, an adjusted HR of 1.96 (95% CI, 1.02 to 3.76) was observed for stroke among modafinil users compared with nonusers. Among the NOSA, the HRs for all-cause death in the OSA were inconsistent across databases.

CONCLUSIONS

Except for few CV outcomes, applying one common protocol generated consistent risk estimates of CV events following modafinil use across cohorts and databases.

Position matters: Validation of medicare hospital claims for myocardial infarction against medical record review in the atherosclerosis risk in communities study

PURPOSE

The objectives of this study were to investigate sensitivity and specificity of myocardial infarction (MI) case definitions using multiple discharge code positions and multiple diagnosis codes when comparing administrative data to hospital surveillance data.

METHODS

Hospital surveillance data for ARIC Study cohort participants with matching participant ID and service dates to Centers for Medicare and Medicaid Services (CMS) hospitalization records for hospitalizations occurring between 2001 and 2013 were included in this study. Classification of Definite or Probable MI from ARIC medical record review defined "gold standard" comparison for validation measures. In primary analyses, an MI was defined with ICD9 code 410 from CMS records. Secondary analyses defined MI using code 410 in combination with additional codes.

RESULTS

A total of 25 549 hospitalization records met study criteria. In primary analysis, specificity was at least 0.98 for all CMS definitions by discharge code position. Sensitivity ranged from 0.48 for primary position only to 0.63 when definition included any discharge code position. The sensitivity of definitions including codes 410 and 411.1 were higher than sensitivity observed when using code 410 alone. Specificity of these alternate definitions was higher for women (0.98) than for men (0.96).

CONCLUSION

Algorithms that rely exclusively on primary discharge code position will miss approximately 50% of all MI cases due to low sensitivity of this definition. We recommend defining MI by code 410 in any of first 5 discharge code positions overall and by codes 410 and 411.1 in any of first 3 positions for sensitivity analyses of women.

Comparative Cardiovascular Risk of Abatacept and Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis With and Without Diabetes Mellitus: A Multidatabase Cohort Study

BACKGROUND

We examined the cardiovascular risk of abatacept compared with tumor necrosis factor (TNF) inhibitors in patients with rheumatoid arthritis with and without diabetes mellitus (DM).

METHODS AND RESULTS

We conducted a cohort study of patients with rheumatoid arthritis who newly started abatacept or TNF inhibitors using claims data from Medicare and MarketScan. The primary outcome was a composite cardiovascular end point of myocardial infarction (MI), stroke/transient ischemic attack, and coronary revascularization. To account for >60 baseline characteristics, abatacept initiators were 1:1 propensity score (PS) matched to TNF initiators in each database. Cox proportional hazards models estimated hazard ratio (HR) and 95% confidence interval (CI) in the PS-matched cohort per database. A fixed-effects meta-analysis pooled database-specific HRs. We included a total of 13 039 PS-matched pairs of abatacept and TNF inhibitor initiators (6103 pairs in Medicare and 6936 pairs in MarketScan). A total of 34.7% in Medicare and 19.8% in MarketScan had baseline DM. The HR (95% CI) for the primary outcome associated with abatacept use versus TNF inhibitor was 0.81 (0.66-0.99) in Medicare and 0.95 (0.74-1.23) in MarketScan, with a pooled HR of 0.86 (95% CI, 0.73-1.01; P=0.3 for heterogeneity). The risk of the primary outcome was lower in abatacept initiators versus TNF inhibitors in the DM subgroup, with a pooled HR of 0.74 (95% CI, 0.57-0.96; P=0.7 for heterogeneity), but not in the non-DM subgroup, with a pooled HR of 0.94 (95% CI, 0.77-1.14; P=0.4 for heterogeneity).

CONCLUSIONS

In this large population-based cohort of patients with rheumatoid arthritis, abatacept use appeared to be associated with a modestly reduced cardiovascular risk when compared with TNF inhibitor use, particularly in patients with DM.

Changes in Statin Adherence Following an Acute Myocardial Infarction Among Older Adults: Patient Predictors and the Association With Follow-Up With Primary Care Providers and/or Cardiologists

BACKGROUND

Hospitalizations for acute myocardial infarctions (AMIs) are associated with changes in statin adherence. It is unclear to what extent adherence changes, which patients are likely to change, and how post-discharge follow-up is associated with statin adherence change.

METHODS AND RESULTS

This retrospective study used Medicare data for all fee-for-service beneficiaries 66 years and older with an AMI hospitalization in 2008-2010 and statin use before their index AMI. Multivariable multinomial logistic regression models (odds ratio [OR] and 99% confidence interval [CI]) were applied to assess associations between both patient characteristics and follow-up with a primary care provider and/or cardiologist with the outcome of statin adherence change (increase or decrease) from the 6-month pre- to 6-month post-AMI periods. Of 113 296 patients, 64.0% had no change in adherence, while 19.7% had increased and 16.3% had decreased adherence after AMI hospitalization. Black and Hispanic patients were more likely to have either increased or decreased adherence than white patients. Patients who required coronary artery bypass graft surgery (OR, 1.34; 99% CI, 1.21-1.49) or percutaneous transluminal coronary angioplasty/stent procedure (OR, 1.25; 99% CI, 1.17-1.32) during their index hospitalization were more likely to have increased adherence. Follow-up with a primary care provider was only mildly associated with increased adherence (OR, 1.08; 99% CI, 1.00-1.16), while follow-up with a cardiologist (OR, 1.15; 99% CI, 1.05-1.25) or both provider types (OR, 1.21; 99% CI, 1.12-1.30) had stronger associations with increased adherence.

CONCLUSIONS

Post-AMI changes in statin adherence varied by patient characteristics, and improved adherence was associated with post-discharge follow-up care, particularly with a cardiologist or both a primary care provider and a cardiologist.

A threshold trajectory was revealed by isolating the effects of hemoglobin rate of rise in anemia of chronic kidney disease

BACKGROUND

To assess cardiovascular risk among various hemoglobin (Hb) rates of rise (RoR) in chronic kidney disease (CKD) patients with anemia who have initiated therapy with erythropoiesis stimulating agents (ESAs).

METHODS

Observational cohort of CKD patients initiating ESA therapy from the Centricity® database, 1990-2011. Proportional hazards models tested the hypothesis that a slower Hb RoR (0 < g/dl/month ⩽ 0.125) is associated with a lower cardiovascular (CV) incidence [composite of fatal/nonfatal myocardial infarction (MI) and stroke] compared with faster RoR (0.125 < g/dl/month ⩽ 2.0, and >2.0 g/dl/month).

RESULTS

A total of 9220 patients receiving ESAs were followed for an average of 3.1 years. Slow (group B) RoR versus medium (group C') and fast (group D') RoR in Hb, throughout all Hb milestones, was associated with lower risk of the composite endpoint [B (slow) versus D' (fast) [hazard ratio (HR) = 0.20 (0.11, 0.39), p < 0.0001]; B versus C' (medium) [HR = 0.34 (0.19, 0.62), p = 0.0004], and C' versus D' [HR = 0.60 (0.42, 0.85), p = 0.005]]. Within achieved Hb milestones, HRs were: B versus D' at milestone ⩾ 14.1 g/dl [HR = 0.17 (0.05, 0.56); p = 0.004] and at milestone 12.6-14.0 [HR = 0.18 (0.07, 0.46), p = 0.0004].

CONCLUSION

Rapid Hb rise is associated with adverse CV outcomes, with markedly lower risk for rates below a threshold trajectory of 0.125 g/dl/month, even with complete correction.

Comparative Safety and Effectiveness of Denosumab Versus Zoledronic Acid in Patients With Osteoporosis: A Cohort Study

Limited head-to-head comparative safety and effectiveness data exist between denosumab and zoledronic acid in real-world healthcare. We aimed to examine the safety and effectiveness of denosumab compared to zoledronic acid with regard to risk of serious infection and cardiovascular disease (CVD) and osteoporotic fracture. We conducted a cohort study using claims data (2009-2013) from a US commercial insurance plan database. We included patients aged ≥50 years who were newly initiated on denosumab or zoledronic acid. The primary outcomes were (1) hospitalization for serious infection; (2) composite CVD endpoint including myocardial infarction, stroke, coronary revascularization, and heart failure; and (3) nonvertebral osteoporotic fracture including hip, wrist, forearm, and pelvic fracture. To control for potential confounders, we used 1:1 propensity score (PS) matching. Cox proportional hazards models compared the risk of serious infection, CVD, and osteoporotic fracture within 365 days after initiation of denosumab versus zoledronic acid. After PS matching, a total of 2467 pairs of denosumab and zoledronic acid initiators were selected with a mean age of 63 years and 96% were female. When compared with zoledronic acid, denosumab was not associated with an increased risk of serious infection (HR 0.81; 95% confidence interval [CI], 0.55 to 1.21) or CVD (HR 1.11; 95% CI, 0.60 to 2.03). Similar results were obtained for each component of CVD. The risk of osteoporotic fracture was also similar between groups (HR 1.21; 95% CI, 0.84 to 1.73). This large population-based cohort study shows that denosumab and zoledronic acid have comparable clinical safety and effectiveness with regard to the risk of serious infection, CVD, and osteoporosis fracture within 365 days after initiation of medications. © 2016 American Society for Bone and Mineral Research.

Health literacy and 30-day hospital readmission after acute myocardial infarction

OBJECTIVE

To assess the validity of a predictive model of health literacy, and to examine the relationship between derived health literacy estimates and 30-day hospital readmissions for acute myocardial infarction (AMI).

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

A National Institute of Aging (NIA) study cohort of 696 adult, English-speaking primary care patients, aged 55-74 years, was used to assess the validity of derived health literacy estimates. Claims from 7733 Medicare beneficiaries hospitalised for AMI in 2008 in North Carolina and Illinois were used to investigate the association between health literacy estimates and 30-day hospital readmissions.

MEASURES

The NIA cohort was administered 3 common health literacy assessments (Newest Vital Sign, Test of Functional Health Literacy in Adults, and Rapid Estimate of Adult Literacy in Medicine). Health literacy estimates at the census block group level were derived via a predictive model. 30-day readmissions were measured from Medicare claims data using a validated algorithm.

RESULTS

Fair agreement was found between derived estimates and in-person literacy assessments (Pearson Correlation coefficients: 0.38-0.51; κ scores: 0.38-0.40). Medicare enrollees with above basic literacy according to derived health literacy estimates had an 18% lower risk of a 30-day readmission (RR=0.82, 95% CI 0.73 to 0.92) and 21% lower incidence rate of 30-day readmission (IRR=0.79, 95% CI 0.68 to 0.87) than patients with basic or below basic literacy. After adjusting for demographic and clinical characteristics, the risk of 30-day readmission was 12% lower (p=0.03), and the incidence rate 16% lower (p<0.01) for patients with above basic literacy.

CONCLUSIONS

Health literacy, as measured by a predictive model, was found to be a significant, independent predictor of 30-day readmissions. As a modifiable risk factor with evidence-based solutions, health literacy should be considered in readmission reduction efforts.

Effects of xanthine oxidase inhibitors on cardiovascular disease in patients with gout: a cohort study

BACKGROUND

Hyperuricemia and gout are associated with an increased risk of cardiovascular disease (CVD). It is unknown whether treating hyperuricemia with xanthine oxidase inhibitors (XOIs), including allopurinol and febuxostat, modifies cardiovascular risks.

METHODS

We used US insurance claims data to conduct a cohort study among gout patients, comparing XOI initiators with non-users with hyperuricemia defined as serum uric acid level ≥6.8 mg/dL. We calculated incidence rates of a composite nonfatal cardiovascular outcome that included myocardial infarction, coronary revascularization, stroke, and heart failure. Propensity score (PS)-matched Cox proportional hazards regression compared the risk of composite cardiovascular endpoint in XOI initiators vs those with untreated hyperuricemia, controlling for baseline confounders. In a subgroup of patients with uric acid levels available, PS-matched Cox regression further adjusted for baseline uric acid levels.

RESULTS

There were 24,108 PS-matched pairs with a mean age of 51 years and 88% male. The incidence rate per 1000 person-years for composite CVD was 24.1 (95% confidence interval [CI] 22.6-26.0) in XOI initiators and 21.4 (95% CI, 19.8-23.2) in the untreated hyperuricemia group. The PS-matched hazard ratio for composite CVD was 1.16 (95% CI, 0.99-1.34) in XOI initiators vs those with untreated hyperuricemia. In subgroup analyses, the PS-matched hazard ratio for composite CVD adjusted for serum uric acid levels was 1.10 (95% CI, 0.74-1.64) among XOI initiators.

CONCLUSIONS

Among patients with gout, initiation of XOI was not associated with an increased or decreased cardiovascular risk compared with those with untreated hyperuricemia. Subgroup analyses adjusting for baseline uric acid levels also showed no association between XOI and cardiovascular risk.

The association of the treatment with glucagon-like peptide-1 receptor agonist exenatide or insulin with cardiovascular outcomes in patients with type 2 diabetes: a retrospective observational study

BACKGROUND

To evaluate the association of treatment with glucagon-like peptide-1 (GLP-1) receptor agonist exenatide and/or insulin on macrovascular outcomes in patients with type 2 diabetes (T2DM).

METHODS

We conducted a retrospective longitudinal pharmaco-epidemiological study using large ambulatory care data to evaluate the risks of heart failure (HF), myocardial infarction (MI) and stroke in established T2DM patients who received a first prescription of exenatide twice daily (EBID) or insulin between June 2005 and May 2009, with follow-up data available until December 2012. Three treatment groups were: EBID with oral antidiabetes drugs (OADs) (EBID, n = 2804), insulin with OADs (Insulin, n = 28551), and those who changed medications between EBID and insulin or had combination of EBID and insulin during follow-up, along with OADs (EBID + insulin, n = 7870). Multivariate Cox-regression models were used to evaluate the association of treatment groups with the risks of macrovascular events.

RESULTS

During a median 3.5 years of follow-up, cardiovascular event rates per 1000 person-years were significantly lower for the EBID and EBID + insulin groups compared to the insulin group (HF: 4.4 and 6.1 vs. 17.9; MI: 1.1 and 1.2 vs. 2.5; stroke: 2.4 and 1.8 vs. 6.1). Patients in the EBID/EBID + insulin group had significantly reduced risk of HF, MI and stroke by 61/56%, 50/38% and 52/63% respectively, compared to patients in the insulin group (p < 0.01).

CONCLUSIONS

Treatment with exenatide, with or without concomitant insulin was associated with reduced macrovascular risks compared to insulin; although inherent potential bias in epidemiological studies should be considered.

Dipeptidyl peptidase-4 inhibitors do not increase the risk of cardiovascular events in type 2 diabetes: a cohort study

AIMS

Two recent randomized controlled trials of type 2 diabetes mellitus (T2DM) patients with history of, or at high risk of, cardiovascular disease (CVD) showed no risk of ischemic cardiovascular events associated with dipeptidyl peptidase-4 inhibitors (DPP4i), but an increased risk of heart failure (HF) with saxagliptin. We evaluated the risk of CVD including myocardial infarction (MI), stroke, coronary revascularization, and HF associated with DPP4i in T2DM patients with and without baseline CVD as used in the community.

METHODS

Using US commercial insurance claims data (2005-2012), we conducted a cohort study that included initiators of DPP4i and non-DPP4i treatments. Composite CVD endpoints including MI, stroke, coronary revascularization, and HF were defined with a hospital discharge diagnosis or procedure code. Cox proportional hazards models compared the risk of composite and individual CVD endpoints in propensity score (PS)-matched initiators of DPP4 versus non-DPP4i.

RESULTS

We included 79,538 (18 % with baseline CVD) persons in PS-matched pairs of DPP4i and non-DPP4i initiators. The incidence rate per 1,000 person-years for composite CVD was 30.30 (95 % CI 28.24-32.51) in DPP4i and 34.76 (95 % CI 32.34-37.36) in non-DPP4i. The PS-matched hazard ratio (HR) for composite CVD was 0.87 (95 % CI 0.79-0.96) in DPP4i versus non-DPP4i. The PS-matched HR for HF was 0.81 (95 % CI 0.70-0.94) in DPP4i versus non-DPP4i. Among patients with baseline CVD, there was no increased risk of CVD or HF associated with DPP4i use.

CONCLUSIONS

Among T2DM patients, initiating DPP4i was not associated with a greater risk of CVD or HF compared to non-DPP4i initiators.

Cardiovascular, bleeding, and mortality risks in elderly Medicare patients treated with dabigatran or warfarin for nonvalvular atrial fibrillation

BACKGROUND

The comparative safety of dabigatran versus warfarin for treatment of nonvalvular atrial fibrillation in general practice settings has not been established.

METHODS AND RESULTS

We formed new-user cohorts of propensity score-matched elderly patients enrolled in Medicare who initiated dabigatran or warfarin for treatment of nonvalvular atrial fibrillation between October 2010 and December 2012. Among 134 414 patients with 37 587 person-years of follow-up, there were 2715 primary outcome events. The hazard ratios (95% confidence intervals) comparing dabigatran with warfarin (reference) were as follows: ischemic stroke, 0.80 (0.67-0.96); intracranial hemorrhage, 0.34 (0.26-0.46); major gastrointestinal bleeding, 1.28 (1.14-1.44); acute myocardial infarction, 0.92 (0.78-1.08); and death, 0.86 (0.77-0.96). In the subgroup treated with dabigatran 75 mg twice daily, there was no difference in risk compared with warfarin for any outcome except intracranial hemorrhage, in which case dabigatran risk was reduced. Most patients treated with dabigatran 75 mg twice daily appeared not to have severe renal impairment, the intended population for this dose. In the dabigatran 150-mg twice daily subgroup, the magnitude of effect for each outcome was greater than in the combined-dose analysis.

CONCLUSIONS

In general practice settings, dabigatran was associated with reduced risk of ischemic stroke, intracranial hemorrhage, and death and increased risk of major gastrointestinal hemorrhage compared with warfarin in elderly patients with nonvalvular atrial fibrillation. These associations were most pronounced in patients treated with dabigatran 150 mg twice daily, whereas the association of 75 mg twice daily with study outcomes was indistinguishable from warfarin except for a lower risk of intracranial hemorrhage with dabigatran.

Comparing pioglitazone to insulin with respect to cancer, cardiovascular and bone fracture endpoints, using propensity score weights

Background

Diabetes is an important global disease, associated with significant morbidity and an increased risk of death due to chronic end-organ complications. The thiazolidinediones, used mainly as third-line agents in type 2 diabetes mellitus (T2DM), have been associated with some safety concerns, such as an increased risk of bladder cancer, an increased risk of bone fracture and heterogeneous effects on cardiovascular events.

Objective

This study aimed to evaluate safety data on pioglitazone for several outcomes and examine them in context with each other as well as with insulin, another third-line treatment for T2DM.

Methods

This retrospective cohort study extracted data from May 1, 2000 until June 30, 2010, from the i3 InVision Data Mart™ database. To adjust for the testing of multiple hypotheses, the Holm method was applied to endpoints representing potential harm from pioglitazone treatment, separately from those representing potential benefit from pioglitazone. The study population included patients with T2DM ≥ 45 years old who were new users of either pioglitazone or insulin. Key outcomes were incident cases of a composite of myocardial infarction (MI) or stroke requiring hospitalization; bone fracture requiring hospitalization; bladder cancer; and a composite of nine other selected cancers. Kaplan–Meier curves were generated and hazard ratios (HRs) for pioglitazone versus insulin were estimated from Cox proportional hazards models adjusted with inverse probability of treatment weights derived from propensity scores.

Results

A total of 56,536 patients (pioglitazone group 38,588; insulin group 17,948) qualified for the study. The mean follow-up was 2.2 years for pioglitazone and 1.9 years for insulin patients. Weighted survival analysis of the composite of MI and stroke, as well as the composite of nine cancers, yielded significant differences in favour of pioglitazone. For the composite of MI and stroke, the HR for pioglitazone versus insulin was 0.44 (95 % confidence interval [CI] 0.39–0.50, p < 0.0001). Modelling of the composite of nine selected cancers produced an HR of 0.78 (95 % CI 0.71–0.85, p < 0.0001). A non-statistically significant difference in favour of pioglitazone was observed in the incidence rate of bone fracture requiring hospitalization (HR 0.86, 95 % CI 0.74–1.01, p = 0.058). For bladder cancer, the overall incidence rates were relatively low and showed no significant difference between the two groups; the HR for pioglitazone versus insulin was 0.92 (95 % CI 0.63–1.33, p = 0.64).

Conclusion

Compared with insulin, pioglitazone was associated with a significant reduction in the risk of MI and stroke requiring hospitalization, and a significant reduction in the risk of other selected cancers. While pioglitazone treatment may be linked with a lower risk of bladder cancer and bone fracture relative to insulin, these differences were not statistically significant.

Prevalent but moderate variation across small geographic regions in patient nonadherence to evidence-based preventive therapies in older adults after acute myocardial infarction

BACKGROUND

Patient long-term adherence to β-blockers, HMG-CoA reductase inhibitors (statins), and angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) after acute myocardial infarction (AMI) is alarmingly low. It is unclear how prevalent patient adherence may be across small geographic areas and whether this geographic prevalence may vary.

METHODS

This is a retrospective cohort study using Medicare service claims files from 2007 to 2009 with Medicare beneficiaries 65 years and above who were alive 30 days after the index AMI hospitalization between January 1, 2008 and December 31, 2008 (N=85,017). The adjusted proportions of patients adherent to β-blockers, statins, and ACEIs/ARBs, respectively, in the 12 months after discharge across the 306 Hospital Referral Regions (HRRs) were measured and compared by control chart. The intracluster correlation coefficient (ICC) and the additional prediction power from this small-area variation on individual patient adherence were assessed.

RESULTS

The adjusted proportion of patients adherent across HRRs ranged from 58% to 74% (median, 66%) for β-blockers, from 57% to 67% (median, 63%) for ACEIs/ARBs, and from 58% to 73% (median, 66%) for statins. The ICC was 0.053 (95% CI, 0.043-0.064) for β-blockers, 0.050 (95% CI, 0.039-0.061) for ACEIs/ARBs, and 0.041 (95% CI, 0.031-0.052) for statins. The adjusted proportion of patients adherent across HRRs increased the c-statistic by 0.01-0.02 (P < 0.0001).

CONCLUSIONS

Nonadherence to evidence-based preventive therapies post-AMI among older adults was prevalent across small geographic regions. Moderate small-area variation in patient adherence exists.

Validation of Diagnostic and Procedural Codes for Identification of Acute Cardiovascular Events in US Veterans with Rheumatoid Arthritis

Objective:

To assess the accuracy of International Classification of Diseases, Ninth Revision, and Current Procedural Terminology codes for identifying cardiovascular (CV) events (myocardial infarction [MI], stroke, coronary artery bypass graft [CABG], and percutaneous coronary intervention [PCI]) in enrollees of the Veterans Affairs Rheumatoid Arthritis (VARA) registry.

Design:

We performed a validation study from VARA enrollment until 6/1/2010 to compare the accuracy of CV events in those with and without CV-event coding in inpatient and outpatient records to evaluate for CV events +/− 3 months of the coding. The positive predictive value (PPV) was calculated, and codes with a PPV ≥50% were included in a composite coding algorithm.

Results:

We evaluated 107 individuals for 21 CV-event codes and 60 individuals without CV-event coding. The PPV varied between 0–100%. Composite coding algorithms’ PPV ranged from 70–100%.

Conclusions:

Validation of these algorithms allows for identification of acute CV events with known accuracy. The sensitivity and PPV of coding algorithms for CABG and PCI exceed that of stroke and MI.

Lower incidence of macrovascular complications in patients on insulin glargine versus those on basal human insulins: a population-based cohort study in Italy

BACKGROUND AND AIM

The aim of this study was to compare the use of insulin glargine and intermediate/long-acting human insulin (HI) in relation to the incidence of complications in diabetic patients.

METHODS AND RESULTS

A population-based cohort study was conducted using administrative data from four local health authorities in the Abruzzo Region (900,000 inhabitants). Diabetic patients without macrovascular diseases and treated with either intermediate/long-acting HI or glargine were followed for 3-years; the incidence of diabetic (macrovascular, microvascular and metabolic) complications was ascertained by hospital discharge claims and estimated using Cox proportional hazard models. Propensity score (PS) matching was also used to adjust for significant differences in the baseline characteristics between the two groups.

RESULTS

Overall, 1921 diabetic patients were included: 744 intermediate/long-acting HI and 1177 glargine users. During the 3-year follow-up, 209 (28.1%) incident events of any diabetic complication occurred in the intermediate/long-acting HI and 159 (13.5%) in the glargine group. After adjustment for covariates, glargine users had an HR (95% CI) of 0.57 (0.44-0.74) for any diabetic complication and HRs of 0.61 (0.44-0.84), 0.58 (0.33-1.04) and 0.35 (0.18-0.70) for macrovascular, microvascular and metabolic complications, respectively, compared to intermediate/long-acting HI users. PS analyses supported these findings.

CONCLUSIONS

The use of glargine is associated with a lower risk of macrovascular complications compared with traditional basal insulins. However, limitations inherent to the study design including the short length of observation and the lack of data on metabolic control or diabetes duration, do not allow us to consider this association as a proof of causality.

Cardiovascular and mortality risk in elderly Medicare beneficiaries treated with olmesartan versus other angiotensin receptor blockers

PURPOSE

In the randomized trial, Randomized Olmesartan and Diabetes Microalbuminuria Prevention, acute cardiovascular death was increased nearly fivefold in diabetic patients treated with high-dose olmesartan, an angiotensin receptor blocker (ARB), compared with placebo.

METHODS

Medicare beneficiaries were entered into new-user cohorts of olmesartan or other ARBs and followed on therapy for occurrence of acute myocardial infarction, stroke, or death. Analyses focused on specific subgroups defined by diabetes status, ARB dose, and duration of therapy. Hazard ratios (HR) with 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression, with other ARBs as reference.

RESULTS

A total of 158,054 olmesartan and 724,673 other ARB users were followed for 54,285 and 260,390 person-years, respectively, during which 9237 endpoint events occurred. Lower-dose olmesartan was not associated with increased risk for any endpoint, regardless of duration of use. High-dose olmesartan for 6 months or longer was associated with increased risk of death in patients with diabetes (HR 2.03, 95%CI 1.09-3.75, p = 0.02) and with reduced risk in nondiabetic patients (HR 0.46, 95%CI 0.24-0.86, p = 0.01). Some, but not all, sensitivity analyses suggested that selective prescribing of olmesartan to healthier patients (channeling bias) may have accounted for the reduced risk in nondiabetic patients.

CONCLUSIONS

High-dose olmesartan was associated with an increased risk of death in diabetic patients treated for 6 months or longer and with a reduced risk of death in nondiabetic patients, when compared with use of other ARBs. This latter effect was probably because of selective prescribing of olmesartan to healthier patients, although effect modification cannot be excluded. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Cardiovascular risk in rheumatoid arthritis: comparing TNF-α blockade with nonbiologic DMARDs

BACKGROUND

Elevated tumor necrosis factor (TNF)-α likely contributes to the excess cardiovascular risk observed in rheumatoid arthritis. We compared the cardiovascular risk in rheumatoid arthritis patients starting a TNF-α blocking agent versus a nonbiologic disease-modifying antirheumatic drug (nbDMARD).

METHODS

Subjects with rheumatoid arthritis participating in several different US insurance programs between 1998 and 2007 who received methotrexate were eligible. Those who added a TNF-α blocking agent were compared with subjects who added a nbDMARD in Cox regression models stratified by propensity score decile and adjusted for oral glucocorticoid dosage. We examined the composite cardiovascular end point of myocardial infarction, stroke, or coronary re-vascularization after 6 months.

RESULTS

We compared 8656 new users of a nbDMARD with 11,587 new users of a TNF-α blocking agent with similar baseline covariates. Incidence rates per 100 person-years for the composite cardiovascular end point were 3.05 (95% confidence interval [CI], 2.54-3.65) for nbDMARDs and 2.52 (95% CI, 2.12-2.98) for TNF-α blocking agents. The hazard ratio (HR) for the TNF-α blocking agent compared with nbDMARD carrying the first exposure forward was 0.80 (95%, CI 0.62-1.04), while the HR for the as-treated analysis was 0.71 (95% CI, 0.52-0.97). The potential cardiovascular benefit of TNF-α blocking agents was strongest among individuals ≥65 years of age (HR 0.52; 95% CI, 0.34 -0.77; P for interaction = 0.075).

CONCLUSION

Among subjects with rheumatoid arthritis, TNF-α blocking agents may be associated with a reduced risk of cardiovascular events compared with an nbDMARD. Randomized controlled clinical trials should be considered to test this hypothesis.

Cardiovascular and mortality risks in Parkinson's disease patients treated with entacapone

The controlled trial Stalevo Reduction in Dyskinesia Evaluation in Parkinson's Disease (STRIDE-PD) reported an unexpected increase in acute myocardial infarction (AMI) with entacapone use in patients with Parkinson's disease (PD). The authors investigated whether entacapone increased cardiovascular and mortality risk compared with the use of a non-levodopa dopamine agonist (DA) or a selective monoamine oxidase type-B inhibitor (MAOBI). Using national Medicare data, a new-user cohort of elderly patients with PD treated with entacapone was propensity score (PS) matched with new users of either DA or MAOBI. The PS model included variables for sociodemographics, cardiovascular disease, medications, prior PD treatment, and comorbidities. Cox proportional hazards regression was used to compare on-therapy time to event for AMI, stroke, and death with DA-MAOBI as a reference. Study cohorts included 8681 entacapone-treated and 17,362 DA-MAOBI-treated initators who were followed for 2569 and 5385 person-years, respectively. Cohorts were closely balanced for all covariates. During follow-up, there were 106 AMIs, 89 strokes, and 201 deaths. The hazard ratio (HR) and 95% confidence interval (CI) associated with entacapone use was 0.86 (95% CI, 0.57-1.30) for AMI, 0.85 (95% CI, 0.54-1.35) for stroke, and 0.79 (95% CI, 0.58-1.07) for death. The risk was unchanged for treatment of ≤ 6 months' and>6 months' duration and was unaffected by adjustment for time-varying levodopa use during follow-up. The risk of each endpoint was not differentially affected by diabetes, ischemic heart disease, or kidney failure status. However, the risk of stroke was modified by the presence (HR, 2.09; 95% CI, 0.98-4.45) or absence (HR, 0.51; 95% CI, 0.27-0.95) of advanced PD-related morbidities (P value for interaction=0.004). Entacapone was not associated with an increased risk of AMI, stroke, or death in elderly patients with PD.

Validation of acute myocardial infarction in the Food and Drug Administration's Mini-Sentinel program

PURPOSE

To validate an algorithm based upon International Classification of Diseases, 9(th) revision, Clinical Modification (ICD-9-CM) codes for acute myocardial infarction (AMI) documented within the Mini-Sentinel Distributed Database (MSDD).

METHODS

Using an ICD-9-CM-based algorithm (hospitalized patients with 410.x0 or 410.x1 in primary position), we identified a random sample of potential cases of AMI in 2009 from four Data Partners participating in the Mini-Sentinel Program. Cardiologist reviewers used information abstracted from hospital records to assess the likelihood of an AMI diagnosis based on criteria from the Joint European Society of Cardiology and American College of Cardiology Global Task Force. Positive predictive values (PPVs) of the ICD-9-based algorithm were calculated.

RESULTS

Of the 153 potential cases of AMI identified, hospital records for 143 (93%) were retrieved and abstracted. Overall, the PPV was 86.0% (95% confidence interval; 79.2%, 91.2%). PPVs ranged from 76.3% to 94.3% across the four Data Partners.

CONCLUSIONS

The overall PPV of potential AMI cases, as identified using an ICD-9-CM-based algorithm, may be acceptable for safety surveillance; however, PPVs do vary across Data Partners. This validation effort provides a contemporary estimate of the reliability of this algorithm for use in future surveillance efforts conducted using the Food and Drug Administration's MSDD.

Comparative effectiveness of sulfonylurea and metformin monotherapy on cardiovascular events in type 2 diabetes mellitus: a cohort study

BACKGROUND

The effects of sulfonylureas and metformin on outcomes of cardiovascular disease (CVD) in type 2 diabetes are not well-characterized.

OBJECTIVE

To compare the effects of sulfonylureas and metformin on CVD outcomes (acute myocardial infarction and stroke) or death.

DESIGN

Retrospective cohort study.

SETTING

National Veterans Health Administration databases linked to Medicare files.

PATIENTS

Veterans who initiated metformin or sulfonylurea therapy for diabetes. Patients with chronic kidney disease or serious medical illness were excluded.

MEASUREMENTS

Composite outcome of hospitalization for acute myocardial infarction or stroke, or death, adjusted for baseline demographic characteristics; medications; cholesterol, hemoglobin A1c, and serum creatinine levels; blood pressure; body mass index; health care utilization; and comorbid conditions.

RESULTS

Among 253 690 patients initiating treatment (98 665 with sulfonylurea therapy and 155 025 with metformin therapy), crude rates of the composite outcome were 18.2 per 1000 person-years in sulfonylurea users and 10.4 per 1000 person-years in metformin users (adjusted incidence rate difference, 2.2 [95% CI, 1.4 to 3.0] more CVD events with sulfonylureas per 1000 person-years; adjusted hazard ratio [aHR], 1.21 [CI, 1.13 to 1.30]). Results were consistent for both glyburide (aHR, 1.26 [CI, 1.16 to 1.37]) and glipizide (aHR, 1.15 [CI, 1.06 to 1.26]) in subgroups by CVD history, age, body mass index, and albuminuria; in a propensity score-matched cohort analysis; and in sensitivity analyses.

LIMITATION

Most of the veterans in the study population were white men; data on women and minority groups were limited but reflective of the Veterans Health Administration population.

CONCLUSION

Use of sulfonylureas compared with metformin for initial treatment of diabetes was associated with an increased hazard of CVD events or death.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality and the U.S. Department of Health and Human Services.

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.

ADHD drugs and serious cardiovascular events in children and young adults

BACKGROUND

Adverse-event reports from North America have raised concern that the use of drugs for attention deficit-hyperactivity disorder (ADHD) increases the risk of serious cardiovascular events.

METHODS

We conducted a retrospective cohort study with automated data from four health plans (Tennessee Medicaid, Washington State Medicaid, Kaiser Permanente California, and OptumInsight Epidemiology), with 1,200,438 children and young adults between the ages of 2 and 24 years and 2,579,104 person-years of follow-up, including 373,667 person-years of current use of ADHD drugs. We identified serious cardiovascular events (sudden cardiac death, acute myocardial infarction, and stroke) from health-plan data and vital records, with end points validated by medical-record review. We estimated the relative risk of end points among current users, as compared with nonusers, with hazard ratios from Cox regression models.

RESULTS

Cohort members had 81 serious cardiovascular events (3.1 per 100,000 person-years). Current users of ADHD drugs were not at increased risk for serious cardiovascular events (adjusted hazard ratio, 0.75; 95% confidence interval [CI], 0.31 to 1.85). Risk was not increased for any of the individual end points, or for current users as compared with former users (adjusted hazard ratio, 0.70; 95% CI, 0.29 to 1.72). Alternative analyses addressing several study assumptions also showed no significant association between the use of an ADHD drug and the risk of a study end point.

CONCLUSIONS

This large study showed no evidence that current use of an ADHD drug was associated with an increased risk of serious cardiovascular events, although the upper limit of the 95% confidence interval indicated that a doubling of the risk could not be ruled out. However, the absolute magnitude of such an increased risk would be low. (Funded by the Agency for Healthcare Research and Quality and the Food and Drug Administration.).

Traumeel - an emerging option to nonsteroidal anti-inflammatory drugs in the management of acute musculoskeletal injuries

Musculoskeletal injuries are on the rise. First-line management of such injuries usually employs the RICE (rest, ice, compression, and elevation) approach to limit excessive inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs) are also commonly used to limit inflammation and to control pain. Traumeel^®, a preparation with bioregulatory effects is also used to treat the symptoms associated with acute musculoskeletal injuries, including pain and swelling. Traumeel is a fixed combination of biological and mineral extracts, which aims to apply stimuli to multiple targets to restore normal functioning of regulatory mechanisms. This paper presents the accumulating evidence of Traumeel’s action on the inflammatory process, and of its efficacy and tolerability in randomized trials, as well as observational and surveillance studies for the treatment of musculoskeletal injuries. Traumeel has shown comparable effectiveness to NSAIDs in terms of reducing symptoms of inflammation, accelerating recovery, and improving mobility, with a favorable safety profile. While continued research and development is ongoing to broaden the clinical evidence of Traumeel in acute musculoskeletal injury and to further establish its benefits, current information suggests that Traumeel may be considered as an anti-inflammatory agent that is at least as effective and appears to be better tolerated than NSAIDs.

Outcomes with concurrent use of clopidogrel and proton-pump inhibitors: a cohort study

BACKGROUND

Proton-pump inhibitors (PPIs) and clopidogrel are frequently coprescribed, although the benefits and harms of their concurrent use are unclear.

OBJECTIVE

To examine the association between concurrent use of PPIs and clopidogrel and the risks for hospitalizations for gastroduodenal bleeding and serious cardiovascular disease.

DESIGN

Retrospective cohort study using automated data to identify patients who received clopidogrel between 1999 through 2005 after hospitalization for coronary heart disease.

SETTING

Tennessee Medicaid program.

PATIENTS

20,596 patients (including 7593 concurrent users of clopidogrel and PPIs) hospitalized for myocardial infarction, coronary artery revascularization, or unstable angina pectoris.

MEASUREMENTS

Baseline and follow-up drug use was assessed from automated records of dispensed prescriptions. Primary outcomes were hospitalizations for gastroduodenal bleeding and serious cardiovascular disease (fatal or nonfatal myocardial infarction or sudden cardiac death, stroke, or other cardiovascular death).

RESULTS

Pantoprazole and omeprazole accounted for 62% and 9% of concurrent PPI use, respectively. Adjusted incidence of hospitalization for gastroduodenal bleeding in concurrent PPI users was 50% lower than that in nonusers (hazard ratio, 0.50 [95% CI, 0.39 to 0.65]). For patients at highest risk for bleeding, PPI use was associated with an absolute reduction of 28.5 (CI, 11.7 to 36.9) hospitalizations for gastroduodenal bleeding per 1000 person-years. The hazard ratio associated with concurrent PPI use for risk for serious cardiovascular disease was 0.99 (CI, 0.82 to 1.19) for the entire cohort and 1.01 (CI, 0.76 to 1.34) for the subgroup of patients who had percutaneous coronary interventions with stenting during the qualifying hospitalization.

LIMITATIONS

Unmeasured confounding and misclassification of exposure (no information on adherence or over-the-counter use of drugs) and end points (not confirmed by medical record review) were possible. Because many patients entered the cohort from hospitals with relatively few cohort members, the analysis relied on the assumption that after adjustment for observed covariates, PPI users from one such hospital could be compared with nonusers from a different hospital.

CONCLUSION

In patients with serious coronary heart disease treated with clopidogrel, concurrent PPI use was associated with reduced incidence of hospitalizations for gastroduodenal bleeding. The corresponding point estimate for serious cardiovascular disease was not increased; however, the 95% CI included a clinically important increased risk.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality and National Heart, Lung, and Blood Institute.

Outcomes with concurrent use of clopidogrel and proton-pump inhibitors: a cohort study

BACKGROUND

Proton-pump inhibitors (PPIs) and clopidogrel are frequently coprescribed, although the benefits and harms of their concurrent use are unclear.

OBJECTIVE

To examine the association between concurrent use of PPIs and clopidogrel and the risks for hospitalizations for gastroduodenal bleeding and serious cardiovascular disease.

DESIGN

Retrospective cohort study using automated data to identify patients who received clopidogrel between 1999 through 2005 after hospitalization for coronary heart disease.

SETTING

Tennessee Medicaid program.

PATIENTS

20,596 patients (including 7593 concurrent users of clopidogrel and PPIs) hospitalized for myocardial infarction, coronary artery revascularization, or unstable angina pectoris.

MEASUREMENTS

Baseline and follow-up drug use was assessed from automated records of dispensed prescriptions. Primary outcomes were hospitalizations for gastroduodenal bleeding and serious cardiovascular disease (fatal or nonfatal myocardial infarction or sudden cardiac death, stroke, or other cardiovascular death).

RESULTS

Pantoprazole and omeprazole accounted for 62% and 9% of concurrent PPI use, respectively. Adjusted incidence of hospitalization for gastroduodenal bleeding in concurrent PPI users was 50% lower than that in nonusers (hazard ratio, 0.50 [95% CI, 0.39 to 0.65]). For patients at highest risk for bleeding, PPI use was associated with an absolute reduction of 28.5 (CI, 11.7 to 36.9) hospitalizations for gastroduodenal bleeding per 1000 person-years. The hazard ratio associated with concurrent PPI use for risk for serious cardiovascular disease was 0.99 (CI, 0.82 to 1.19) for the entire cohort and 1.01 (CI, 0.76 to 1.34) for the subgroup of patients who had percutaneous coronary interventions with stenting during the qualifying hospitalization.

LIMITATIONS

Unmeasured confounding and misclassification of exposure (no information on adherence or over-the-counter use of drugs) and end points (not confirmed by medical record review) were possible. Because many patients entered the cohort from hospitals with relatively few cohort members, the analysis relied on the assumption that after adjustment for observed covariates, PPI users from one such hospital could be compared with nonusers from a different hospital.

CONCLUSION

In patients with serious coronary heart disease treated with clopidogrel, concurrent PPI use was associated with reduced incidence of hospitalizations for gastroduodenal bleeding. The corresponding point estimate for serious cardiovascular disease was not increased; however, the 95% CI included a clinically important increased risk.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality and National Heart, Lung, and Blood Institute.