Lessons learned from a multi-data source research collaboration: The mirabegron post-authorization safety study program.

BACKGROUND: Many factors contribute to developing and conducting a successful multi-data source, non-interventional, post-authorization safety study (NI-PASS) for submission to multiple health authorities. Such studies are often large undertakings; evaluating and sharing lessons learned can provide useful insights to others considering similar studies. OBJECTIVES: We discuss challenges and key methodological and organizational factors that led to the delivery of a successful post-marketing requirement (PMR)/PASS program investigating the risk of cardiovascular and cancer events among users of mirabegron, an oral medication for the treatment of overactive bladder. RESULTS: We provide context and share learnings, including sections on research program collaboration, scientific transparency, organizational approach, mitigation of uncertainty around potential delays, validity of study outcomes, selection of data sources and optimizing patient numbers, choice of comparator groups and enhancing precision of estimates of associations, potential confounding and generalizability of study findings, and interpretation of results. CONCLUSIONS: This large PMR/PASS program was a long-term commitment from all parties and benefited from an effective coordinating center and extensive scientific interactions across research partners, scientific advisory board, study sponsor, and health authorities, and delivered useful learnings related to the design and organization of multi-data source NI-PASS.

Liver, renal, genitourinary and diabetic ketoacidosis risks among new users of empagliflozin versus dipeptidyl peptidase-4 inhibitors in patients with type 2 diabetes: Post-authorization safety study based on multinational cohorts.

AIM: To estimate risks of diabetic ketoacidosis (DKA), acute liver injury (ALI), acute kidney injury (AKI), chronic kidney disease (CKD), severe complications of urinary tract infection (UTI) and genital infection (GI) among patients with type 2 diabetes initiating empagliflozin versus those initiating a dipeptidyl peptidase-4 (DPP-4) inhibitor. MATERIALS AND METHODS: In this large multinational, observational, new-user cohort study in UK, Danish and US healthcare data sources, patients initiated empagliflozin or a DPP-4 inhibitor between August 2014 and August 2019, were aged ≥18 years, and had ≥12 months' continuous health plan enrolment. Incidence rates by exposure and incidence rate ratios, adjusted for propensity-score deciles, were calculated. RESULTS: In total, 64 599 empagliflozin initiators and 203 315 DPP-4 inhibitor initiators were included. There was an increased risk [pooled adjusted incidence rate ratios (95% confidence interval)] of DKA [2.19 (1.74-2.76)] and decreased risks of ALI [0.77 (0.50-1.19) in patients without predisposing conditions of liver disease; 0.70 (0.56-0.88) in all patients] and AKI [0.54 (0.41-0.73)]. In the UK data, there was an increased risk of GI [males: 4.04 (3.46-4.71); females: 3.24 (2.81-3.74)] and decreased risks of CKD [0.53 (0.43-0.65)] and severe complications of UTI [0.51 (0.37-0.72)]. The results were generally consistent in subgroup and sensitivity analyses. CONCLUSIONS: Compared with DDP-4 inhibitor use, empagliflozin use was associated with increased risks of DKA and GI and decreased risks of ALI, AKI, CKD and severe complications of UTI. These associations are consistent with previous studies and known class effects of sodium-glucose cotransporter 2 inhibitors, including renoprotective effects and beneficial effects on alanine aminotransferase levels.

HARmonized Protocol Template to Enhance Reproducibility of hypothesis evaluating real-world evidence studies on treatment effects: A good practices report of a joint ISPE/ISPOR task force.

PROBLEM: Ambiguity in communication of key study parameters limits the utility of real-world evidence (RWE) studies in healthcare decision-making. Clear communication about data provenance, design, analysis, and implementation is needed. This would facilitate reproducibility, replication in independent data, and assessment of potential sources of bias. WHAT WE DID: The International Society for Pharmacoepidemiology (ISPE) and ISPOR-The Professional Society for Health Economics and Outcomes Research (ISPOR) convened a joint task force, including representation from key international stakeholders, to create a harmonized protocol template for RWE studies that evaluate a treatment effect and are intended to inform decision-making. The template builds on existing efforts to improve transparency and incorporates recent insights regarding the level of detail needed to enable RWE study reproducibility. The overarching principle was to reach for sufficient clarity regarding data, design, analysis, and implementation to achieve 3 main goals. One, to help investigators thoroughly consider, then document their choices and rationale for key study parameters that define the causal question (e.g., target estimand), two, to facilitate decision-making by enabling reviewers to readily assess potential for biases related to these choices, and three, to facilitate reproducibility. STRATEGIES TO DISSEMINATE AND FACILITATE USE: Recognizing that the impact of this harmonized template relies on uptake, we have outlined a plan to introduce and pilot the template with key international stakeholders over the next 2 years. CONCLUSION: The HARmonized Protocol Template to Enhance Reproducibility (HARPER) helps to create a shared understanding of intended scientific decisions through a common text, tabular and visual structure. The template provides a set of core recommendations for clear and reproducible RWE study protocols and is intended to be used as a backbone throughout the research process from developing a valid study protocol, to registration, through implementation and reporting on those implementation decisions.

HARmonized Protocol Template to Enhance Reproducibility of Hypothesis Evaluating Real-World Evidence Studies on Treatment Effects: A Good Practices Report of a Joint ISPE/ISPOR Task Force.

OBJECTIVES: Ambiguity in communication of key study parameters limits the utility of real-world evidence (RWE) studies in healthcare decision-making. Clear communication about data provenance, design, analysis, and implementation is needed. This would facilitate reproducibility, replication in independent data, and assessment of potential sources of bias. METHODS: The International Society for Pharmacoepidemiology (ISPE) and ISPOR-The Professional Society for Health Economics and Outcomes Research (ISPOR) convened a joint task force, including representation from key international stakeholders, to create a harmonized protocol template for RWE studies that evaluate a treatment effect and are intended to inform decision-making. The template builds on existing efforts to improve transparency and incorporates recent insights regarding the level of detail needed to enable RWE study reproducibility. The over-arching principle was to reach for sufficient clarity regarding data, design, analysis, and implementation to achieve 3 main goals. One, to help investigators thoroughly consider, then document their choices and rationale for key study parameters that define the causal question (e.g., target estimand), two, to facilitate decision-making by enabling reviewers to readily assess potential for biases related to these choices, and three, to facilitate reproducibility. STRATEGIES TO DISSEMINATE AND FACILITATE USE: Recognizing that the impact of this harmonized template relies on uptake, we have outlined a plan to introduce and pilot the template with key international stakeholders over the next 2 years. CONCLUSION: The HARmonized Protocol Template to Enhance Reproducibility (HARPER) helps to create a shared understanding of intended scientific decisions through a common text, tabular and visual structure. The template provides a set of core recommendations for clear and reproducible RWE study protocols and is intended to be used as a backbone throughout the research process from developing a valid study protocol, to registration, through implementation and reporting on those implementation decisions.

Risk Assessment of Acute Myocardial Infarction and Stroke Associated with Long-Acting Muscarinic Antagonists, Alone or in Combination, versus Long-Acting beta2-Agonists.

Background: The long-acting muscarinic antagonist (LAMA) aclidinium was approved in Europe in 2012 to relieve symptoms in adult patients with chronic obstructive pulmonary disease (COPD). A post-authorization safety study was initiated to assess potential cardiovascular risks associated with LAMAs versus long-acting beta2-agonists. Purpose: To estimate incidence rates and adjusted incidence rate ratios (IRRs) for acute myocardial infarction (AMI), stroke, and major adverse cardiac events (MACE) in new users of aclidinium, aclidinium/formoterol, tiotropium, other LAMA, long-acting beta-agonists/inhaled corticosteroids (LABA/ICS), and LAMA/LABA compared with initiators of LABA. Patients and Methods: This population-based cohort study included patients with COPD aged ≥40 years initiating COPD medications in the UK Clinical Practice Research Datalink (CPRD) Aurum database from 2012 to 2019. Poisson regression models were used to estimate the IRR for AMI, stroke, and MACE in users of COPD medications versus LABA, adjusting for clinically relevant covariables. Results: The study included 11,121 new users of aclidinium, 4804 of aclidinium/formoterol, 56,198 of tiotropium, 23,856 of other LAMA, 17,450 of LAMA/LABA, 70,289 of LABA/ICS, and 13,716 of LABA. During periods of continuous medication use after initiation (current use), crude incidence rates per 1000 person-years for AMI ranged from 8.7 (aclidinium/formoterol) to 12.4 (LAMA/LABA), for stroke ranged from 4.8 (aclidinium/formoterol) to 7.2 (LAMA/LABA), and for MACE ranged from 13.5 (aclidinium/formoterol) to 19.3 (LAMA/LABA). Using LABA as reference, adjusted IRRs [95% confidence intervals] were close to 1 for all study drugs for AMI (lowest for aclidinium/formoterol, 0.95 [0.60-1.52], and highest for LAMA/LABA, 1.23 [0.91-1.67]), stroke (lowest for aclidinium/formoterol, 0.64 [0.39-1.06], and highest for tiotropium, 1.02 [0.81-1.27] for tiotropium) and for MACE (lowest for aclidinium, 0.93 [0.75-1.16], and highest for LAMA/LABA, 1.24 [0.97-1.59]). Conclusion: Risks of AMI, stroke, and MACE in current users of aclidinium, aclidinium/formoterol, tiotropium, other LAMA, LAMA/LABA, or LABA/ICS were similar to the risks among current users of LABA.

Incidence of Acute Renal Failure in Patients Using Levetiracetam Versus Other Antiseizure Medications: A Voluntary Post-Authorization Safety Study.

INTRODUCTION: Acute kidney injury is an expected adverse drug reaction listed in the European Union (EU) Summary of Product Characteristics (SmPC) for levetiracetam, one of the most widely used modern antiseizure medications (ASMs). OBJECTIVE: We conducted a voluntary post-authorization safety study to characterize the rate of acute renal failure (ARF) in patients exposed to levetiracetam versus other ASMs. METHODS: New users of ASMs without prior renal dysfunction were identified and followed for 30 days in the IBM® MarketScan® database (USA, January 2008-December 2017). ARF was defined as a diagnosis on inpatient or emergency department claims. We estimated adjusted incidence rates, incidence rate ratios (IRRs), and incidence rate differences (IRDs) of ARF in patients initiating levetiracetam versus other ASMs. RESULTS: Overall, 110,336 patients were eligible for the monotherapy cohort and 96,215 were eligible for the polytherapy cohort. The overall crude rate of ARF following a new ASM was 6.0 and 6.5 per 10,000 patients for the 'monotherapy' and 'polytherapy' cohorts, respectively, in the first 30 days after the index date. In the monotherapy cohort, the IRR for ARF was 1.37 (95% confidence interval [CI] 0.80-2.34) and the corresponding IRD was 2.0 (95% CI - 1.12 to 5.12) additional ARFs per 10,000 patient-months. In the polytherapy cohort, the adjusted IRR for ARF was 0.94 (95% CI 0.51-1.74) and the corresponding IRD was - 0.42 cases per 10,000 patient-months (95% CI - 4.01 to 3.17). CONCLUSIONS: The rate of ARFs in ASM new users was very low. In patients without prior ASMs, the estimated difference in risk of ARF associated with initiation of levetiracetam versus initiation of other ASMs was small, with 95% CIs compatible with small protective or harmful effects. In patients receiving polytherapy, the difference was compatible with the null and the 95% CI with small protective or harmful effects.

Characteristics of New Users of Aclidinium Bromide, Aclidinium/Formoterol, and Other COPD Medications in the United Kingdom, Denmark, and Germany.

BACKGROUND AND OBJECTIVES: Aclidinium bromide was approved in the European Union for the treatment of chronic obstructive pulmonary disease (COPD) in adult patients in 2012 and in a fixed-dose combination with formoterol in 2014. We characterised new users of aclidinium, aclidinium/formoterol and other COPD medications and evaluated off-label prescribing of these medications in three European populations. METHODS: We described demographic characteristics, comorbidities, comedications, COPD severity and off-label prescribing of new users of aclidinium, aclidinium/formoterol and other COPD medications in patients with COPD aged ≥ 40 years in the Clinical Practice Research Datalink (CPRD, UK), Danish National Health Databases, and German Pharmacoepidemiological Research Database (GePaRD) between 2015 and 2017. RESULTS: We included 17,668 new users of aclidinium (CPRD, 4871; Denmark, 2836; GePaRD, 9961) and 14,808 new users of aclidinium/formoterol (CPRD, 2153; Denmark, 2586; GePaRD, 10,069). Study patients were of similar age, except in GePaRD, where users of long-acting beta2-agonists (LABA)/inhaled corticosteroids were younger. Patients had multiple comorbidities and used multiple comedications-most frequently hypertension (50-79%) and short-acting beta2-agonists (26-84%). Aclidinium users in CPRD and long-acting anticholinergics/LABA users in Denmark and GePaRD had the highest frequency of severe/very severe COPD. Off-label prescribing of aclidinium (5.0% [CPRD]-8.9% [Denmark]) and aclidinium/formoterol (2.6% [GePaRD]-3.2% [CPRD]) was low, and the main reason was asthma without a COPD diagnosis. CONCLUSIONS: Aclidinium and aclidinium/formoterol were mostly prescribed according to label, with preference given to older patients with more severe COPD and to patients with a high prevalence of comorbidities and comedication use.

Cardiovascular Risk in Users of Mirabegron Compared with Users of Antimuscarinic Treatments for Overactive Bladder: Findings from a Non-Interventional, Multinational, Cohort Study.

INTRODUCTION: During clinical trials, mirabegron, a ß3-adrenoreceptor agonist, was associated with increased vital signs vs placebo in patients with overactive bladder. OBJECTIVE: The purpose of this study was to compare incidence rates of adverse cardiovascular (CV) outcomes following mirabegron or antimuscarinic use. METHODS: We conducted an observational post-marketing safety study utilising real-world data. The study population was identified within five sources: Danish and Swedish National Registers, Clinical Practice Research Datalink (UK), Optum (USA) and Humana (USA). Episodes of time when patients were new users of mirabegron or antimuscarinics (October 2012-December 2018) were sourced from prescriptions and matched on propensity scores. Occurrences of major adverse cardiovascular events (MACE), acute myocardial infarction (AMI), stroke, CV mortality and all-cause mortality were identified. Outcome incidence rates and hazard ratios from Cox models were estimated. RESULTS: Overall, 152,026 mirabegron and 152,026 antimuscarinic episodes were matched. The population consisted of 63.1% women and 72.6% were ≥ 65 years old. There were no appreciable differences in the incidence rates of MACE, AMI or stroke between users of mirabegron and antimuscarinics. Incidence rates of CV mortality (hazard ratio 0.83, 95% confidence interval 0.73-0.95) and all-cause mortality (hazard ratio 0.80, 95% confidence interval 0.76-0.84) were no higher with mirabegron vs antimuscarinics. Results restricted to episodes at high risk for CV events or stratified by age (< 65 years, ≥ 65 years) or prior overactive bladder medication use were consistent with overall findings. CONCLUSIONS: This large, multinational study found no higher risk of MACE, AMI, stroke, CV mortality or all-cause mortality among users of mirabegron relative to users of antimuscarinics.

During clinical trials, mirabegron, which is a treatment for overactive bladder, was associated with small increases in heart rate and blood pressure. This study was conducted to compare the frequency of cardiac events following the use of mirabegron or antimuscarinics, a group of treatments also used to treat overactive bladder. We obtained the data for this study from four countries: Denmark, Sweden, the UK and the USA. We identified people who were new users of mirabegron or antimuscarinics from 2012 to 2018 using prescription or dispensing records. Occurrences of major cardiac events, heart attack, stroke, death due to cardiac events and death from any cause were evaluated. Overall, we identified 152,026 times when mirabegron or antimuscarinics were each used as new treatments. Most of the people in the study were women (63.1%) and at least 65 years old (72.6%). There were no notable differences between the treatment groups with regard to how often major cardiac events, heart attack or stroke occurred. Further, death due to cardiac events and death from any cause were no higher with mirabegron compared with antimuscarinics. We obtained similar results when the data were assessed for patients who were at high risk for cardiac events or split by age (less than 65 years or at least 65 years) or a history of overactive bladder medication use. In conclusion, this large study involving data from several countries found no higher risk of major cardiac events, heart attack, stroke or death among people prescribed mirabegron compared with antimuscarinics.

A Cohort Study to Evaluate the Risk of Hospitalisation for Congestive Heart Failure Associated with the Use of Aclidinium and Other Chronic Obstructive Pulmonary Disease Medications in the UK Clinical Practice Research Datalink.

BACKGROUND: The long-acting anticholinergic (LAMA) aclidinium was approved in Europe in 2012 to relieve symptoms in adults with chronic obstructive pulmonary disease (COPD). A Post-Authorisation Safety Study (PASS) was initiated to assess potential cardiovascular safety concerns for aclidinium. OBJECTIVE: To estimate the adjusted incidence rate ratio (IRR) for hospitalisation for heart failure in patients with COPD who were new users of aclidinium, tiotropium, other LAMA, long-acting beta-agonists/inhaled corticosteroids (LABA/ICS), and LAMA/LABA were compared with initiators of LABA. METHODS: This population-based cohort study included patients with COPD aged ≥40 years initiating COPD medications in the Clinical Practice Research Datalink (CPRD) GOLD in the United Kingdom from 2012 to 2017. Medications were identified via general practice prescriptions. The first-ever hospitalisations for heart failure were identified in the Hospital Episode Statistics, and general practitioner records from the CPRD. Poisson regression models were used to estimate the IRR for hospitalisation for heart failure in users of COPD medications versus LABA, adjusting for clinically relevant covariates. RESULTS: The study included 4350 new users of aclidinium, 23,405 of tiotropium, 6977 of other LAMAs, 3122 of LAMA/LABA, 26,093 of LABA/ICS, and 5678 of LABA. Mean age was 69-70 years across medication groups. Aclidinium users had the highest proportion of severe COPD, and LABA users had the lowest (35% vs 19%, respectively). Crude incidence rates per 1000 person-years for the first-ever hospitalisation for heart failure ranged from 6.9 in LABA to 9.5 in aclidinium. Using LABA as reference, adjusted IRRs (95% confidence interval) for first-ever hospitalisation for heart failure were 0.90 (0.53-1.53) for aclidinium, 1.02 (0.69-1.51) for tiotropium, 0.86 (0.50-1.47) for other LAMAs, 1.09 (0.41-2.92) for LAMA/LABA, and 1.01 (0.69, 1.48) for LABA/ICS. CONCLUSION: The study did not find increased risks of hospitalisations for heart failure in new users of aclidinium, tiotropium, other LAMAs, LAMA/LABA, and LABA/ICS compared with LABA.

Use of intravenous iron and risk of anaphylaxis: A multinational observational post-authorisation safety study in Europe.

PURPOSE: This post-authorisation safety study estimated the risk of anaphylaxis in patients receiving intravenous (IV) iron in Europe, with interest in iron dextran and iron non-dextrans. Studies conducted in the United States have reported risk of anaphylaxis to IV iron ranging from 2.0 to 6.8 per 10 000 first treatments. METHODS: Cohort study of IV iron new users, captured mostly through pharmacy ambulatory dispensing, from populations covered by health and administrative data sources in five European countries from 1999 to 2017. Anaphylaxis events were identified through an algorithm that used parenteral penicillin as a positive control. RESULTS: A total of 304 210 patients with a first IV iron treatment (6367 iron dextran), among whom 13-16 anaphylaxis cases were identified and reported as a range to comply with data protection regulations. The pooled unadjusted incidence proportion (IP) ranged from 0.4 (95% confidence interval [CI], 0.2-0.9) to 0.5 (95% CI, 0.3-1.0) per 10 000 first treatments. No events were identified at first dextran treatments. There were 231 294 first penicillin treatments with 30 potential cases of anaphylaxis (IP = 1.2; 95% CI, 0.8-1.7 per 10 000 treatments). CONCLUSION: We found an IP of anaphylaxis from 0.4 to 0.5 per 10 000 first IV iron treatments. The study captured only a fraction of IV iron treatments administered in hospitals, where most first treatments are likely to happen. Due to this limitation, the study could not exclude a differential risk of anaphylaxis between iron dextran and iron non-dextrans. The IP of anaphylaxis in users of penicillin was consistent with incidences reported in the literature.

A study of cancer occurrence in users of mirabegron and antimuscarinic treatments for overactive bladder.

OBJECTIVE: This post-authorization safety study (EU PAS Register Number: EUPAS16088) was designed to compare the incidence of cancer outcomes in patients treated with mirabegron versus antimuscarinic medications. METHODS: Cohorts of mirabegron initiators during 2012-2018 were propensity-score matched to antimuscarinic medication initiators within real-world data sources (Danish National Registers, Swedish National Registers, Clinical Practice Research Datalink [UK], Optum [US], and Humana [US]). Incident cancer cases were identified during follow-up from direct linkage to cancer registers or validated through medical record review or through physician questionnaires. Comparisons of sex-specific composite cancer outcomes (cancer of the lung/bronchus, colon/rectum, melanoma of skin, urinary bladder, non-Hodgkin lymphoma, kidney/renal pelvis, pancreas, prostate in men and breast and uterus in women) were made overall and for person-time in the first year and after the first year following start of treatment, for all ages and for the subgroup ≥65 years. RESULTS: Among the 80,637 mirabegron initiators matched to 169,885 antimuscarinic medication initiators, 68% were at least 65 years of age and 66% were women. Over 5000 incident cancer cases were observed overall. Incidence rates were higher for men than women for composite and individual cancer outcomes. The pooled fixed effects hazard ratios for composite cancer outcomes (all ages) were 1.05 (95% confidence interval [CI]: 0.98-1.14) for women and 1.06 (95% CI: 0.98-1.14) for men. Results were similar in persons ≥65 years. CONCLUSIONS: The results suggest no association between mirabegron use and risk of cancer, compared with antimuscarinic medications, in either men or women. Registration: EU PAS Register Number: EUPAS16088.

Long-Term Risk of Skin Cancer and Lymphoma in Users of Topical Tacrolimus and Pimecrolimus: Final Results from the Extension of the Cohort Study Protopic Joint European Longitudinal Lymphoma and Skin Cancer Evaluation (JOELLE).

PURPOSE: Evidence is insufficient to infer whether topical calcineurin inhibitors (TCIs; tacrolimus and pimecrolimus) cause malignancy. The study objective was to estimate the long-term risk of skin cancer and lymphoma associated with topical TCI use in adults and children, separately. PATIENTS AND METHODS: A cohort study in Denmark, Sweden, UK, and the Netherlands was conducted. Adjusted incidence rate ratios (IRRs) and 95% confidence intervals (CIs) were calculated for nonmelanoma skin cancer (NMSC), melanoma, cutaneous T-cell lymphoma (CTCL), non-Hodgkin lymphoma (NHL) excluding CTCL, and Hodgkin lymphoma (HL) in new users of TCIs versus users of moderate/high-potency topical corticosteroids. RESULTS: The study included 126,908/61,841 adults and 32,605/27,961 children initiating treatment with tacrolimus/pimecrolimus, respectively. Follow-up was ≥10 years for 19% of adults and 32% of children. Incidence rate ratios and (95% confidence intervals) for tacrolimus versus corticosteroid users in adults were <1 for melanoma, non-Hodgkin lymphoma, and Hodgkin lymphoma; and 1.80 (1.25-2.58) for cutaneous T-cell lymphoma. For pimecrolimus, IRRs in adults were <1 for non-Hodgkin lymphoma, cutaneous T-cell lymphoma, and Hodgkin's lymphoma; and 1.21 (1.03-1.41) for melanoma; and 1.28 (1.20-1.35) for nonmelanoma skin cancer. In children, results were inconclusive due to few events. In adults, incidence rate ratios ≥5 years after first topical calcineurin inhibitor exposure were not higher than in overall analyses. CONCLUSION: Overall, we found little evidence associating use of topical calcineurin inhibitors with skin cancer and lymphoma; confounding by indication, surveillance bias, and reverse causation may have influenced these results. Even if causal, the public health impact of these excess risks would be low and confined to the first years of exposure.

Validation of cardiovascular outcomes and risk factors in the Clinical Practice Research Datalink in the United Kingdom.

PURPOSE: Strategies to identify and validate acute myocardial infarction (AMI) and stroke in primary-care electronic records may impact effect measures, but to an unknown extent. Additionally, the validity of cardiovascular risk factors that could act as confounders in studies on those endpoints has not been thoroughly assessed in the United Kingdom Clinical Practice Research Datalink's (CPRD's) GOLD database. We explored the validity of algorithms to identify cardiovascular outcomes and risk factors and evaluated different outcome-identification strategies using these algorithms for estimation of adjusted incidence rate ratios (IRRs). METHODS: First, we identified AMI, stroke, smoking, obesity, and menopausal status in a cohort treated for overactive bladder by applying computerized algorithms to primary care medical records (2004-2012). We validated these cardiovascular outcomes and risk factors with physician questionnaires (gold standard for this analysis). Second, we estimated IRRs for AMI and stroke using algorithm-identified and questionnaire-confirmed cases, comparing these with IRRs from cases identified through linkage with hospitalization/mortality data (best estimate). RESULTS: For AMI, the algorithm's positive predictive value (PPV) was >90%. Initial algorithms for stroke performed less well because of inclusion of codes for prevalent stroke; algorithm refinement increased PPV to 80% but decreased sensitivity by 20%. Algorithms for smoking and obesity were considered valid. IRRs based on questionnaire-confirmed cases only were closer to IRRs estimated from hospitalization/mortality data than IRRs from algorithm-identified cases. CONCLUSIONS: AMI, stroke, smoking, obesity, and postmenopausal status can be accurately identified in CPRD. Physician questionnaire-validated AMI and stroke cases yield IRRs closest to the best estimate.

Validity of hospital ICD-10-GM codes to identify acute liver injury in Germany.

PURPOSE: Acute liver injury (ALI) is an important adverse drug reaction. We estimated the positive predictive values (PPVs) of ICD-10-GM codes of ALI used in an international postauthorisation safety study (PASS). METHODS: Analyses used routine data (2007 to 2016, adults) from a German academic hospital in a cross-sectional design. Two algorithms from the PASS were applied to extract potential cases from the hospital information system: specific end point (A) (discharge diagnosis of liver disease-specific codes) and less specific end point (B) (discharge and outpatient-specific and nonspecific codes suggestive of liver injury). ALI cases were confirmed on the basis of plasma liver enzyme activity elevation. Secondary analysis was performed following exclusion of cases with known cancer, chronic liver, biliary and pancreatic disease, heart failure, and alcohol-related disorders, as applied in the PASS. RESULTS: On the basis of ICD codes: outcome A, 154 cases (143 with case notes and lab data for case verification); outcome B, 485 cases (357 with case notes and lab data). ALI was confirmed in 71 outcome A cases, PPV of 49.7% (95% confidence interval [CI], 41.2%-58.1%), and 100 outcome B cases, PPV of 28.0% (95% CI, 23.4%-33.0%). Applying exclusion criteria increased PPV (95% CI) to 62.7% (50.0%-74.2%) for outcome A and 45.7% (37.2%-54.3%) for outcome B. CONCLUSIONS: In safety studies on hepatotoxicity based on routine data using ICD-10-GM discharge codes and when validation of potential cases is not feasible, only the more specific codes should be used to describe ALI, and competing diagnoses for liver injury should be excluded to avoid substantial misclassification.

Validity of ICD-9 and ICD-10 codes used to identify acute liver injury: A study in three European data sources.

PURPOSE: Validating cases of acute liver injury (ALI) in health care data sources is challenging. Previous validation studies reported low positive predictive values (PPVs). METHODS: Case validation was undertaken in a study conducted from 2009 to 2014 assessing the risk of ALI in antidepressants users in databases in Spain (EpiChron and SIDIAP) and the Danish National Health Registers. Three ALI definitions were evaluated: primary (specific hospital discharge codes), secondary (specific and nonspecific hospital discharge codes), and tertiary (specific and nonspecific hospital and outpatient codes). The validation included review of patient profiles (EpiChron and SIDIAP) and of clinical data from medical records (EpiChron and Denmark). ALI cases were confirmed when liver enzyme values met a definition by an international working group. RESULTS: Overall PPVs (95% CIs) for the study ALI definitions were, for the primary ALI definition, 84% (60%-97%) (EpiChron), 60% (26%-88%) (SIDIAP), and 74% (60%-85%) (Denmark); for the secondary ALI definition, 65% (45%-81%) (EpiChron), 40% (19%-64%) (SIDIAP), and 70% (64%-77%) (Denmark); and for the tertiary ALI definition, 25% (18%-34%) (EpiChron), 8% (7%-9%) (SIDIAP), and 47% (42%-52%) (Denmark). The overall PPVs were higher for specific than for nonspecific codes and for hospital discharge than for outpatient codes. The nonspecific code "unspecified jaundice" had high PPVs in Denmark. CONCLUSIONS: PPVs obtained apply to patients using antidepressants without preexisting liver disease or ALI risk factors. To maximize validity, studies on ALI should prioritize hospital specific discharge codes and should include hospital codes for unspecified jaundice. Case validation is required when ALI outpatient cases are considered.

Use of aclidinium did not increase the risk of death in a noninterventional cohort study in the Clinical Practice Research Datalink (CPRD), United Kingdom.

BACKGROUND: Aclidinium bromide is an inhaled long-acting muscarinic antagonist (LAMA). Although the initial potential increased cardiovascular and mortality risk among users of tiotropium has been ruled out by several observational studies, and clinical trials, there are still concerns related to the use of newer LAMA medications. The current study aimed to evaluate the risk of death among users of aclidinium and other LAMAs. METHODS: We conducted a cohort and nested case-control study among patients with COPD aged 40 years or older to compare the risk of all-cause mortality among users of aclidinium and other COPD medications with the risk among users of long-acting ß2 agonists (LABA), in the Clinical Practice Research Datalink (CPRD) in the United Kingdom (2012-2017). RESULTS: Mortality rates per 1,000 person-years were 32.9 for aclidinium, 43.8 for tiotropium, 38.0 for other LAMA, 47.1 for LABA/ICS, and 38.1 for LABA. The RR of death compared with current use of LABA was 0.54 (confidence interval [95% CI], 0.40-0.72) for aclidinium, 0.96 (95% CI, 0.76-1.21) for tiotropium, 0.76 (95% CI, 0.58-0.99) for other LAMA, and 1.08 (95% CI, 0.90-1.31) for LABA/ICS. Decreased risk for death observed among users of aclidinium was driven by overall current single use (RR = 0.41; 95% CI, 0.22-0.79), which corresponded to 26% of the aclidinium users (<15 cases) and not by multiple use (RR = 1.02; 95% CI, 0.71-1.48). CONCLUSION: Use of aclidinium, tiotropium, other LAMA, or LABA/ICS was not associated with an increased risk of all-cause mortality as compared with the use of LABAs.

Risk of Acute Liver Injury in Agomelatine and Other Antidepressant Users in Four European Countries: A Cohort and Nested Case-Control Study Using Automated Health Data Sources.

BACKGROUND: Agomelatine is a melatonin receptor agonist and serotonin 5-HT2C receptor antagonist indicated for depression in adults. Hepatotoxic reactions like acute liver injury (ALI) are an identified risk in the European risk management plan for agomelatine. Hepatotoxic reactions have been reported for other antidepressants, but population studies quantifying these risks are scarce. Antidepressants are widely prescribed, and users often have risk factors for ALI (e.g. metabolic syndrome). OBJECTIVE: The goal was to estimate the risk of ALI associated with agomelatine and other antidepressants (fluoxetine, paroxetine, sertraline, escitalopram, mirtazapine, venlafaxine, duloxetine, and amitriptyline) when compared with citalopram in routine clinical practice. METHOD: A nested case-control study was conducted using data sources in Denmark, Germany, Spain, and Sweden (study period 2009-2014). Three ALI endpoints were defined using International Classification of Diseases (ICD) codes: primary (specific codes) and secondary (all codes) endpoints used only hospital discharge codes; the tertiary endpoint included both inpatient and outpatient settings (all codes). Validation of endpoints was implemented. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for current use were estimated for each data source and combined. RESULTS: We evaluated 3,238,495 new antidepressant and 74,440 agomelatine users. For the primary endpoint, the OR for agomelatine versus citalopram was 0.48 (CI 0.13-1.71). Results were also < 1 when no exclusion criteria were applied (OR 0.37; CI 0.19-0.74), when all exclusion criteria except alcohol and drug abuse were applied (OR 0.47; CI 0.20-1.07), and for the secondary (OR 0.40; CI 0.05-3.11) and tertiary (OR 0.79; CI 0.50-1.25) endpoints. Regarding other antidepressants versus citalopram, most OR point estimates were also below one, although with varying widths of the 95% CIs. The result of the tertiary endpoint and the sensitivity analyses of the primary endpoint were the most precise. CONCLUSION: In this study, using citalopram as a comparator, agomelatine was not associated with an increased risk of ALI hospitalisation. The results for agomelatine should be interpreted in the context of the European risk minimisation measures in place. Those measures may have induced selective prescribing and could explain the lower risk of ALI for agomelatine when compared with citalopram. Most other antidepressants evaluated had ORs suggesting a lower risk than citalopram, but additional studies are required to confirm or refute these results.

Antidepressant use in Denmark, Germany, Spain, and Sweden between 2009 and 2014: Incidence and comorbidities of antidepressant initiators.

BACKGROUND: We aimed to describe patterns of use and characteristics of 10 commonly used antidepressants for the period 2009-2014 in Denmark, Germany, Spain, and Sweden. METHODS: Adult initiators from 2009 to 2014 of each study antidepressant were identified in four countries using five data sources: the Danish National registers, GePaRD (Germany), EpiChron (Aragon, Spain), SIDIAP (Catalonia, Spain), and the Swedish National Registers. The study included 10 study antidepressants: citalopram, escitalopram, fluoxetine, paroxetine, sertraline, duloxetine, venlafaxine, amitriptyline, mirtazapine, and agomelatine. RESULTS: Citalopram was the most prescribed study antidepressant, followed by mirtazapine. Paroxetine and agomelatine were the least prescribed antidepressants. Mirtazapine was widely used among older antidepressant initiators with higher percentages of comorbidities at baseline, and fluoxetine was used among young patients. Citalopram and amitriptyline had the lowest percentage of multiple antidepressant use in the 12 months prior to the current treatment episode, while agomelatine, duloxetine, and venlafaxine had the highest percentage of multiple antidepressant use in the year prior to the current treatment episode. LIMITATIONS: The most important limitations are exposure information based on filled prescriptions, focus on antidepressant initiators only, lack of information on the indication, and heterogeneity of the type of data across data sources. CONCLUSIONS: Results of this study including 4.8 million study antidepressant initiators of study antidepressants suggest that citalopram and mirtazapine are the most commonly prescribed antidepressants. Agomelatine and paroxetine were the least used antidepressants in the participating populations. Mirtazapine was the antidepressant most commonly prescribed among older antidepressant initiators with high percentage of comorbidities at baseline, whereas fluoxetine was commonly used among young patients.

GOLD assessment of COPD severity in the Clinical Practice Research Datalink (CPRD).

PURPOSE: To evaluate availability of spirometry and symptom data in the Clinical Practice Research Datalink (United Kingdom) to assess COPD severity using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2016 definition and comparing it with an algorithm used in other studies. METHODS: This was a descriptive, noninterventional, secondary database cohort study of patients with COPD aged 40 years or older, who initiated treatment with specific COPD medications. Patients were classified according to COPD severity (1) in GOLD 2016 "ABCD" categories based on symptoms (Medical Research Council dyspnea grade, COPD Assessment Test, breathlessness), percent predicted FEV1, and exacerbation history and (2) as mild, moderate, severe, or very severe based on treatment and exacerbation history. RESULTS: The study included 63 900 patients with COPD aged 40 years or older that were new users of 1 or more COPD medication of interest. Percent predicted FEV1 was available for 80.9% of patients; symptoms for 75.6% of patients. Classification into GOLD 2016 ABCD categories was possible for 75.6% of the patients. The GOLD 2016 ABCD definition classified more patients under the high-risk categories (22.1%, A; 18.8%, B; 21.3%, C; 37.9%, D) than did the adapted algorithm (7.9%, mild; 48.6%, moderate; 42.1%, severe; 1.4%, very severe). CONCLUSION: Using our adaptation of the GOLD 2016 COPD severity classification, the information in the Clinical Practice Research Datalink allowed us to ascertain COPD severity in approximately 75% of patients with COPD. Algorithms that include medication use tend to misclassify patients with the extreme COPD severity categories.