Applying two approaches to detect unmeasured confounding due to time-varying variables in a self-controlled risk interval design evaluating COVID-19 vaccine safety signals, using myocarditis as a case example.

We test the robustness of the self-controlled risk interval (SCRI) design in a setting where time between doses may introduce time-varying confounding, using both negative control outcomes (NCOs) and quantitative bias analysis (QBA). All vaccinated cases identified from 5 European databases between 1 September 2020 and end of data availability were included. Exposures were doses 1-3 of the Pfizer, Moderna, AstraZeneca, and Janssen COVID-19 vaccines; outcomes were myocarditis and otitis externa (NCO). The SCRI used a 60-day control window and dose-specific 28-day risk windows, stratified by vaccine brand and adjusted for calendar time. The QBA included two scenarios: (i) baseline probability of the confounder was higher in the control window and (ii) vice versa. The NCO was not associated with any of the COVID-19 vaccine types or doses except Moderna dose 1 (IRR = 1.09, 95%CI 1.01-1.09). The QBA suggested even the strongest literature-reported confounder (COVID-19; RRmyocarditis = 18.3) could only explain away part of the observed effect from IRR = 3 to IRR = 1.40. The SCRI seems robust to unmeasured confounding in the COVID-19 setting, although a strong unmeasured confounder could bias the observed effect upward. Replication of our findings for other safety signals would strengthen this conclusion.

Comparing clinical trial population representativeness to real-world users of 17 biologics approved for immune-mediated inflammatory diseases: An external validity analysis of 66,639 biologic users from the Italian VALORE project.

To date, no population-based studies have specifically explored the external validity of pivotal randomized clinical trials (RCTs) of biologics simultaneously for a broad spectrum of immuno-mediated inflammatory diseases (IMIDs). The aims of this study were, firstly, to compare the patients' characteristics and median treatment duration of biologics approved for IMIDs between RCTs' and real-world setting (RW); secondly, to assess the extent of biologic users treated for IMIDs in the real-world setting that would not have been eligible for inclusion into pivotal RCT for each indication of use. Using the Italian VALORE distributed database (66,639 incident biologic users), adult patients with IMIDs treated with biologics in the Italian real-world setting were substantially older (mean age ± SD: 50 ± 15 years) compared to those enrolled in pivotal RCTs (45 ± 15 years). In the real-world setting, certolizumab pegol was more commonly used by adult women with psoriasis/ankylosing spondylitis (F/M ratio: 1.8-1.9) compared to RCTs (F/M ratio: 0.5-0.6). The median treatment duration (weeks) of incident biologic users in RW was significantly higher than the duration of pivotal RCTs in almost all indications for use and most biologics (4-100 vs. 6-167). Furthermore, almost half (46.4%) of biologic users from RW settings would have been ineligible for inclusion in the respective indication-specific pivotal RCTs. The main reasons were: advanced age, recent history of cancer and presence of other concomitant IMIDs. These findings suggest that post-marketing surveillance of biologics should be prioritized for those patients.

Pharmacological and non-pharmacological treatments in amyotrophic lateral sclerosis: an Italian real-world data study.

BACKGROUND AND PURPOSE: The purpose was to describe the use patterns of pharmacological and non-pharmacological therapies and investigate potential determinants of riluzole use in patients newly diagnosed with amyotrophic lateral sclerosis (ALS) in three Italian regions. METHODS: Amyotrophic lateral sclerosis patients were selected from administrative healthcare databases of Latium, Tuscany and Umbria from 1 January 2014 to 31 December 2019 based on hospital- and disease-specific co-payment exemption data. The first trace of ALS was considered the index date. Incident ALS cases were those without a trace of ALS during the 3-year look back. Patients were described in terms of demographics, clinical characteristics and drug use at baseline, and were classified into four categories based on riluzole use in the 2 years before and 1 year after the index date: prevalent, incident, former users and non-users. Use of symptomatic pharmacological and non-pharmacological therapies was described across these categories during 12 months after the index date. Determinants of riluzole use were also investigated. RESULTS AND CONCLUSIONS: A total of 1636 ALS incident subjects were detected in the three regions, mainly aged 65-74 years. Patients were generally fragile with a high prevalence of comorbidities at baseline. Riluzole was used by 27.4% of the overall study cohort at baseline and steeply increased in the first year after the index date differently between regions (Latium 61.2%, Tuscany 85.0%, Umbria 76.5%), with about half of the subjects being incident users. In the 12 months after the index date, also symptomatic therapies increased, in riluzole users and non-users. Determinants analysis showed that higher patient severity and complexity were associated with a lower likelihood of being treated with riluzole.

COVID-19 and pregnancy: A European study on pre- and post-infection medication use.

PURPOSE: The COVID-19 pandemic has impacted medication needs and prescribing practices, including those affecting pregnant women. Our goal was to investigate patterns of medication use among pregnant women with COVID-19, focusing on variations by trimester of infection and location. METHODS: We conducted an observational study using six electronic healthcare databases from six European regions (Aragon/Spain; France; Norway; Tuscany, Italy; Valencia/Spain; and Wales/UK). The prevalence of primary care prescribing or dispensing was compared in the 30-day periods before and after a positive COVID-19 test or diagnosis. RESULTS: The study included 294,126 pregnant women, of whom 8943 (3.0%) tested positive for, or were diagnosed with, COVID-19 during their pregnancy. A significantly higher use of antithrombotic medications was observed particularly after COVID-19 infection in the second and third trimesters. The highest increase was observed in the Valencia region where use of antithrombotic medications in the third trimester increased from 3.8% before COVID-19 to 61.9% after the infection. Increases in other countries were lower; for example, in Norway, the prevalence of antithrombotic medication use changed from around 1-2% before to around 6% after COVID-19 in the third trimester. Smaller and less consistent increases were observed in the use of other drug classes, such as antimicrobials and systemic corticosteroids. CONCLUSION: Our findings highlight the substantial impact of COVID-19 on primary care medication use among pregnant women, with a marked increase in the use of antithrombotic medications post-COVID-19. These results underscore the need for further research to understand the broader implications of these patterns on maternal and neonatal/fetal health outcomes.

Sharing Is Caring? International Society for Pharmacoepidemiology Review and Recommendations for Sharing Programming Code.

PURPOSE: There is increasing recognition of the importance of transparency and reproducibility in scientific research. This study aimed to quantify the extent to which programming code is publicly shared in pharmacoepidemiology, and to develop a set of recommendations on this topic. METHODS: We conducted a literature review identifying all studies published in Pharmacoepidemiology and Drug Safety (PDS) between 2017 and 2022. Data were extracted on the frequency and types of programming code shared, and other key open science practices (clinical codelist sharing, data sharing, study preregistration, and stated use of reporting guidelines and preprinting). We developed six recommendations for investigators who choose to share code and gathered feedback from members of the International Society for Pharmacoepidemiology (ISPE). RESULTS: Programming code sharing by articles published in PDS ranged from 1.8% in 2017 to 9.5% in 2022. It was more prevalent among articles with a methodological focus, simulation studies, and papers which also shared record-level data. CONCLUSION: Programming code sharing is rare but increasing in pharmacoepidemiology studies published in PDS. We recommend improved reporting of whether code is shared and how available code can be accessed. When sharing programming code, we recommend the use of permanent digital identifiers, appropriate licenses, and, where possible, adherence to good software practices around the provision of metadata and documentation, computational reproducibility, and data privacy.

Describing diversity of real world data sources in pharmacoepidemiologic studies: The DIVERSE scoping review.

PURPOSE: Real-world evidence (RWE) is increasingly used for medical regulatory decisions, yet concerns persist regarding its reproducibility and hence validity. This study addresses reproducibility challenges associated with diversity across real-world data sources (RWDS) repurposed for secondary use in pharmacoepidemiologic studies. Our aims were to identify, describe and characterize practices, recommendations and tools for collecting and reporting diversity across RWDSs, and explore how leveraging diversity could improve the quality of evidence. METHODS: In a preliminary phase, keywords for a literature search and selection tool were designed using a set of documents considered to be key by the coauthors. Next, a systematic search was conducted up to December 2021. The resulting documents were screened based on titles and abstracts, then based on full texts using the selection tool. Selected documents were reviewed to extract information on topics related to collecting and reporting RWDS diversity. A content analysis of the topics identified explicit and latent themes. RESULTS: Across the 91 selected documents, 12 topics were identified: 9 dimensions used to describe RWDS (organization accessing the data source, data originator, prompt, inclusion of population, content, data dictionary, time span, healthcare system and culture, and data quality), tools to summarize such dimensions, challenges, and opportunities arising from diversity. Thirty-six themes were identified within the dimensions. Opportunities arising from data diversity included multiple imputation and standardization. CONCLUSIONS: The dimensions identified across a large number of publications lay the foundation for formal guidance on reporting diversity of data sources to facilitate interpretation and enhance replicability and validity of RWE.

Metadata for Data dIscoverability aNd Study rEplicability in obseRVAtional Studies (MINERVA): Development and Pilot of a Metadata List and Catalogue in Europe.

PURPOSE: Metadata for data dIscoverability aNd study rEplicability in obseRVAtional studies (MINERVA), a European Medicines Agency-funded project (EUPAS39322), defined a set of metadata to describe real-world data sources (RWDSs) and piloted metadata collection in a prototype catalogue to assist investigators from data source discoverability through study conduct. METHODS: A list of metadata was created from a review of existing metadata catalogues and recommendations, structured interviews, a stakeholder survey, and a technical workshop. The prototype was designed to comply with the FAIR principles (findable, accessible, interoperable, reusable), using MOLGENIS software. Metadata collection was piloted by 15 data access partners (DAPs) from across Europe. RESULTS: A total of 442 metadata variables were defined in six domains: institutions (organizations connected to a data source); data banks (data collections sustained by an organization); data sources (collections of linkable data banks covering a common underlying population); studies; networks (of institutions); and common data models (CDMs). A total of 26 institutions were recorded in the prototype. Each DAP populated the metadata of one data source and its selected data banks. The number of data banks varied by data source; the most common data banks were hospital administrative records and pharmacy dispensation records (10 data sources each). Quantitative metadata were successfully extracted from three data sources conforming to different CDMs and entered into the prototype. CONCLUSIONS: A metadata list was finalized, a prototype was successfully populated, and a good practice guide was developed. Setting up and maintaining a metadata catalogue on RWDSs will require substantial effort to support discoverability of data sources and reproducibility of studies in Europe.

Patterns of anti-CGRP mAbs use and variation of triptan consumption following treatment initiation: A descriptive drug utilization study in the Tuscany region, Italy.

OBJECTIVE: To describe the pattern of anti-calcitonin gene-related peptide monoclonal antibodies (anti-CGRP mAbs) utilization in the Tuscany region, Italy, and the variation of triptan consumption after treatment initiation. BACKGROUND: Given the recent commercialization of anti-CGRP mAbs as migraine preventive medications, real-world evidence on their patterns of utilization and their impact on migraine abortive medication use is still limited. METHODS: A retrospective, descriptive, cohort study on the real-world utilization of anti-CGRP mAbs was performed using the population-based regional administrative database of Tuscany. Patients with ≥1 anti-CGRP mAb dispensing (namely erenumab, galcanezumab, fremanezumab) between April 1, 2019, and September 30, 2021, were identified. The first dispensing was the cohort entry (CE). New users (NUs) were patients with no anti-CGRP mAb dispensing before CE. Kaplan-Meier (KM) curves were plotted to describe the cumulative probability of remaining with the initial anti-CGRP mAb during a 15-month follow-up period as a measure of treatment persistence. Among NUs with ≥2 triptan dispensings during the 6 months before CE (i.e., baseline), the mean monthly number of triptan dosage units dispensed was measured in five consecutive follow-up time windows (months 1-3, 4-6, 7-9, 10-12, 13-15) and the difference from the baseline was calculated. RESULTS: A total of 624 NUs (erenumab = 295, galcanezumab = 223, fremanezumab = 106) were identified, of whom 188 (78%) were women. Mean age was 49.2 years (standard deviation [SD] = 12.6). The survival to discontinuation at 6, 12, and 15 months was about 69%, 48%, and 6%, respectively. The survival to switch was about 6% at 15 months. The observed variation of triptan consumption at 3/6/9/12/15 months and the corresponding SD was -4.4 [8.2]/-5.2 [9.0]/-5.5 [9.2]/-5.4 [9.2]/-4.5 [10.0], respectively. CONCLUSION: Patient demographics reflect the place of these medications in therapy. Overall, findings seem to indicate a favorable tolerability and effectiveness profile. Further studies are warranted to better establish the long-term comparative effectiveness, safety, and cost effectiveness of anti-CGRP mAbs compared to other preventive medications.

Utilization patterns, cardiovascular risk, and concomitant serotoninergic medications among triptan users between 2008 and 2018: A gender analysis in one Italian region, Tuscany.

OBJECTIVE: To describe the pattern of triptan use by gender in Tuscany, Italy, focusing on special user populations in which evidence on triptan safety is still not conclusive. BACKGROUND: Growing evidence supports the role of gender differences in migraine pathophysiology and treatment. However, gender impact on triptan real-word utilization has been poorly investigated. METHODS: A retrospective, descriptive, cohort study was performed using the population-based Administrative Healthcare Database of Tuscany region (Italy). Subjects registered in the database on the January 1 of each year between 2008 and 2018 were identified. New users (NU) of triptans (ATC:N02CC*) were patients with one or more triptan dispensation during the year of interest and none in the past. Age, cardiovascular comorbidities representing an absolute or a possible contraindication to triptan utilization, concomitant serotonergic medications, and pattern of triptan use during 1-year follow-up were described by gender. RESULTS: A total of 86,109 patients who received one or more triptan dispensing were identified. Of 64,672 NU (men = 17,039; women = 47,633), 10.2% (6823/64,672) were aged >65 years, who were mostly women (n = 4613). Among NU, men and women with absolute cardiovascular contraindications were 4.3% (740/17,039) and 2.1% (1022/47,633), respectively, while those concomitantly taking serotonergic medications were 17.2% (267/1549) and 21.9% (949/4330), respectively (949/4330). Regular users (two or more dispensing with ≥3 months between first and last observed dispensing) accounted for 26.4% of women (12,597/47,633) and 19.11% of men (3250/17,039); frequent users (≥15 dosage units/month during ≥3 consecutive months) were overall 0.1% (94/64,672) and 62.0% (58/94) of them concomitantly received serotonergic medications. CONCLUSION: Considering gender differences in triptan use highlighted here, large scale observational studies are warranted to better define what populations are safe to use triptans and whether it is appropriate to tighten or relax certain recommendations on triptan use. In the meantime, any suspected adverse drug reaction observed in the special user populations highlighted in this study should be promptly reported.

Cases of acquired hemophilia A following COVID-19 vaccines: Cogent safety signal or possible reporting/detection bias? Preliminary evidence from Tuscany, Italy.

PURPOSE: Several case reports of acquired hemophilia A (AHA) following COVID-19 vaccines were recently published. A possible increased incidence of AHA during the COVID-19 vaccination campaign was also suggested. We aimed at generating evidence for the preliminary assessment of the association between AHA and COVID-19 vaccination through an ecological study in one Italian region, Tuscany. METHODS: An ecological study was performed using the population-based administrative data source of Tuscany. Per each year between 2017 and 2021, we included patients aged 5+ and active into the database as of January 1. Temporal patterns of annual incidence of possible AHA cases and AHA-tested patients were respectively observed. The rates of possible AHA cases per AHA-tested patients were calculated in 2021 and 2017-2019, respectively (calendar year 2020 was excluded because non-representative of the pre-pandemic era). Age-sex standardization was applied. Poisson's 95% confidence intervals (95% CI) were estimated. Statically significant differences were defined as absence of 95% CI overlap. RESULTS: In 2021, standardized incidence of both possible AHA cases (5.6/million subjects/year; 95% CI = 3.4-8.7) and AHA-tested patients (60.7/1000 subjects/year; 95% CI = 60.4-60.9) showed the lowest point estimates, though only the latter was statistically different compared to previous calendar years. The standardized rate of possible AHA cases per AHA-tested patients was 9.2/100000 (95% CI = 5.6-14.3) in 2021 and 12.5/100000 (95% CI = 8.2-18.1) during 2017-2019. CONCLUSIONS: These preliminary findings do not support the hypothesis of an increased incidence of AHA cases during the COVID-19 vaccination campaign. However, in 2021, the still ongoing healthcare access restrictions might have contributed to the low incidence of AHA and laboratory tests observed. Therefore, large-scale multi-database studies are warranted.

Overview of the European post-authorisation study register post-authorization studies performed in Europe from September 2010 to December 2018.

BACKGROUND: The European post-authorisation study (EU PAS) register is a repository launched in 2010 by the European Medicines Agency (EMA). All EMA-requested PAS, commonly observational studies, must be recorded in this register. Multi-database studies (MDS) leveraging secondary data have become an important strategy to conduct PAS in recent years, as reflected by the type of studies registered in the EU PAS register. OBJECTIVES: To analyse and describe PAS in the EU PAS register, with focus on MDS. METHODS: Studies in the EU PAS register from inception to 31st December 2018 were described concerning transparency, regulatory obligations, scope, study type (e.g., observational study, clinical trial, survey, systematic review/meta-analysis), study design, type of data collection and target population. MDS were defined as studies conducted through secondary use of >1 data source not linked at patient-level. Data extraction was carried out independently by 14 centres with expertise in pharmacoepidemiology, using publicly available information in the EU PAS register including study protocol, whenever available, using a standardised data collection form. For validation purposes, a second revision of key fields for a 15% random sample of studies was carried out by a different centre. The inter-rater reliability (IRR) was then calculated. Finally, to identify predictors of primary data collection-based studies/versus those based on secondary use of healthcare databases) or MDS (vs. non-MDS), odds ratios (OR) and 95% confidence intervals (CI) were calculated fitting univariate logistic regression models. RESULTS: Overall, 1426 studies were identified. Clinical trials (N = 30; 2%), systematic reviews/meta-analyses (N = 16; 1%) and miscellaneous study designs (N = 46; 3%) were much less common than observational studies (N = 1227; 86%). The protocol was available for 63% (N = 360) of 572 observational studies requested by a competent authority. Overall, 36% (N = 446) of observational studies were based fully or partially on primary data collection. Of 757 observational studies based on secondary use of data alone, 282 (37%) were MDS. Drug utilisation was significantly more common as a study scope in MDS compared to non-MDS studies. The overall percentage agreement among collaborating centres that collected the data concerning study variables was highest for study type (93.5%) and lowest for type of secondary data (67.8%). CONCLUSIONS: Observational studies were the most common type of studies in the EU PAS register, but 30% used primary data, which is more resource-intensive. Almost half of observational studies using secondary data were MDS. Data recording in the EU PAS register may be improved further, including more widespread availability of study protocols to improve transparency.

Risk of coronavirus disease 2019 hospitalization and mortality in rheumatic patients treated with hydroxychloroquine or other conventional disease-modifying anti-rheumatic drugs in Italy.

OBJECTIVES: To ascertain if the use of hydroxychloroquine(HCQ)/cloroquine(CLQ) and other conventional DMARDs (cDMARDs) and rheumatic diseases per se may be associated with COVID-19-related risk of hospitalization and mortality. METHODS: This case-control study nested within a cohort of cDMARD users was conducted in the Lombardy, Veneto, Tuscany and Lazio regions and Reggio Emilia province. Claims databases were linked to COVID-19 surveillance registries. The risk of COVID-19-related outcomes was estimated using a multivariate conditional logistic regression analysis comparing HCQ/CLQ vs MTX, vs other cDMARDs and vs non-use of these drugs. The presence of rheumatic diseases vs their absence in a non-nested population was investigated. RESULTS: A total of 1275 patients hospitalized due to COVID-19 were matched to 12 734 controls. Compared with recent use of MTX, no association between HCQ/CLQ monotherapy and COVID-19 hospitalization [odds ratio (OR) 0.83 (95% CI 0.69, 1.00)] or mortality [OR 1.19 (95% CI 0.85, 1.67)] was observed. A lower risk was found when comparing HCQ/CLQ use with the concomitant use of other cDMARDs and glucocorticoids. HCQ/CLQ was not associated with COVID-19 hospitalization as compared with non-use. An increased risk for recent use of either MTX monotherapy [OR 1.19 (95% CI 1.05, 1.34)] or other cDMARDs [OR 1.21 (95% CI 1.08, 1.36)] vs non-use was found. Rheumatic diseases were not associated with COVID-19-related outcomes. CONCLUSION: HCQ/CLQ use in rheumatic patients was not associated with a protective effect against COVID-19-related outcomes. The use of other cDMARDs was associated with an increased risk when compared with non-use and, if concomitantly used with glucocorticoids, also vs HCQ/CLQ, probably due to immunosuppressive action.

Utilisation patterns and clinical impact of the introduction of infliximab-biosimilar in Tuscany, Italy: real world evidence following the recommendation of switching for non-medical reasons.

OBJECTIVES: This study was aimed at assessing the impact of a non-medical recommendation on drug-utilisation patterns and clinical outcomes in a central Region of Italy (Tuscany). METHODS: We performed a pre-post study on data collected in Tuscan healthcare administrative databases. We included patients with diagnosis of rheumatoid arthritis, or psoriatic arthritis, or ankylosing spondylitis, or ulcerative colitis, or Crohn's disease, or psoriasis. The first analysis compared patients treated with infliximab on January 1st, 2013 (originator only available) to those on January 1st, 2016 (both originator and biosimilar available). The second analysis compared infliximab-originator users with infliximab-biosimilar ones. Adjusted odds ratios (OR) of persistence on treatment, Emergency Department (ED) admissions, hospitalisations and specialist visits were calculated. RESULTS: The first analysis included 606 patients and the second 434. In both analyses, we did not observe any significant difference in persistence. In the first analysis, the 2016 infliximab-originator cohort showed a significant association with the risk of having at least one ED admission (OR 1.54, 95% CI 1.02 to 2.31). A significant difference of accessing a specialist visit (more frequently rheumatologic) was observed in the 2016 cohort (OR 1.52, 95% CI 1.05 to 2.20). In the second analysis, the risk of having at least one hospitalisation decreased significantly in switchers to infliximab-biosimilar (OR 0.49, 95% CI 0.26 to 0.96). CONCLUSIONS: Our study showed no relevant changes in the clinical outcomes following the introduction of infliximab-biosimilar. The few observed differences observed can be explained mainly by a selective switching to infliximab-biosimilar in patients with lower burden of disease.

Use of antiseizure medications and safety of branded versus generic formulations: A comparative study on Tuscan administrative databases.

PURPOSE: To assess patterns of use of antiseizure medications (ASMs) and to compare the safety of generic versus branded formulations in terms of admission to hospital or to emergency department (ED). METHODS: We conducted a drug utilization study with a propensity score-matched design using the administrative databases of the Italian Tuscany region. New users of ASMs during 2015 with no history of neoplasia were considered and their first prescription was classified as: available only as branded (only-B-ASM); branded with generic available (B-ASM); and generic (G-ASM). Patients with G-ASM first prescription were matched with four patients with B-ASM prescription. Participants were followed up for one year or until the date of death or diagnosis of neoplasia. Cox regression models were fitted to estimate the risk of admission to hospital or ED. RESULTS: We identified 36,601 ASM new-users, including 2094 (6.4%) with only-B-ASM as first prescription, 24,588 (74.9%) with B-ASM, and 5788 (17.6%) with G-ASM. We found no differences in the risk of admission to hospital or ED (Hazard Ratio (HR), 0.92; 95% Confidence Interval (CI), 0.85-1.02) among users of generic ASMs compared to those using branded ASMs. CONCLUSIONS: In our study population, generic ASMs were used less than branded ones. The similarity in the safety of branded and generic formulations suggests that generic ASMs could be the preferred formulation in current clinical practice resulting in a substantial decrease in the cost of treatment.

Direct healthcare costs of chronic kidney disease management in Italy: What cost-savings can be achieved with higher biosimilar uptake and more appropriate use of erythropoiesis-stimulating agents?

PURPOSE: Erythropoiesis-stimulating agents (ESAs), are used for treating chronic kidney disease (CKD)-related anemia, contributing to CKD costs. The study was aimed at investigating direct healthcare costs of CKD patients treated with ESAs and the potential savings achievable by increasing the use of biosimilars and preventing inappropriate ESA use. METHODS: A multi-center, cohort study was conducted using claims databases of five large Italian geographic areas. Yearly mean direct healthcare costs per patient were estimated, stratifying by CKD stage. The total yearly cost and potential savings related to ESA use were estimated: (a) considering 25/50/75% of originator ESA substitution with biosimilars; (b) eliminating inappropriate ESA dispensing. RESULTS: During the study period, the ESA-related yearly mean cost represented 17% of total yearly costs in stage I-III, decreasing to 13% in stage IV-V and 6% in dialysis. Among originator users, assuming a 25% of biosimilar uptake, the annual cost-savings of ESA treatment would represent 10.5% of total ESA costs in CKD stage I-V and 7.7% in dialysis. Among incident ESA users for which hemoglobin levels were available, 9% started inappropriately ESA treatment, increasing to 62.0% during the first year of maintenance therapy. Hypothesizing prevention of the first inappropriate ESA dispensing, the total yearly cost-savings would amount to €35 772, increasing to €167 641 eliminating the inappropriate dispensing during maintenance therapy. CONCLUSIONS: Higher use of lowest cost ESA, prevention of inappropriate ESA use as well as other strategies aimed at slowing down the progressive renal impairment are essential for minimizing clinical and economic burden of CKD.

Outcome misclassification: Impact, usual practice in pharmacoepidemiology database studies and an online aid to correct biased estimates of risk ratio or cumulative incidence.

PURPOSE: It is well documented that outcome misclassification can bias a point estimate. We aimed to understand current practice in addressing this bias in pharmacoepidemiology database studies and to develop an open source application (app) from existing methodology to demonstrate the impact and mechanism of this bias on results. METHODS: Studies of an exposure and a clinical outcome were selected from all Pharmacoepidemiology and Drug Safety publications during 2017 and any reference to outcome misclassification described. An app to correct risk ratio (RR) and cumulative incidence for outcome misclassification was developed from a published methodology and used to demonstrate the impact of correction on point estimates. RESULTS: Eight (19%) of 43 papers selected reported estimates of outcome ascertainment accuracy with positive predictive value (PPV) the most commonly reported measure (7 of 8 studies). Three studies (7%) corrected for the bias, 1 by exposure strata, and 5 (12%) restricted analyses to confirmed cases. The app (app http://apps.p-95.com/ISPE/) uses values of PPV and sensitivity (or a range of possible values) in each exposure strata and returns corrected point estimates and confidence intervals. The app demonstrates that small differences between comparison groups in PPV or sensitivity can introduce bias even when accuracy estimates are high. CONCLUSIONS: Outcome misclassification is not usually corrected in pharmacoepidemiology database studies although correction methods using routinely measured indices are available. Error indices are needed for each comparison group to correct RR estimates for these errors. The app should encourage understanding of this bias and increase adjustment.

Patterns and trends of utilization of incretin-based medicines between 2008 and 2014 in three Italian geographic areas.

BACKGROUND: The incretin-based medicines GLP1 analogues (GLP1a) and dipeptidyl peptidase-4 inhibitors (DPP4i) are hypoglycaemic agents licensed for the treatment of type 2 diabetes mellitus (T2DM). Although these drugs possess comparable efficacy and low risk of hypoglycaemia, differences in terms of route of administration (subcutaneous versus oral), effect on body weight and gastrointestinal tolerabily can impact their actual use in clinical practice. This study aimed to describe the real-world utilization of incretin-based medicines in the Italian clinical practice. METHODS: A multi-database, population-based, descriptive, cohort study was performed using administrative data collected between 2008 and 2014 from three Italian geographic areas. Subjects aged ≥18 were selected. New users were defined as those with ≥1 dispensing of GLP1a or DPP4i during the year of interest and none in the past. Trends of cumulative annual incidence of use in the general adult population were observed. New users of GLP1a or DPP4i were respectively described in terms of demographic characteristics and use of antidiabetic drugs during 1 year before and after the first incretin dispensing. RESULTS: The overall study population included 4,943,952 subjects. A total of 7357 new users of GLP1a and 41,907 of DPP4i were identified during the study period. Incidence of use increased between 2008 (0.2‰ for both GLP1a and DPP4i) and 2011 (GLP1a = 0.6‰; DPP4i = 2.5‰) and slightly decreased thereafter. In 2014, 61% of new GLP1a users received once-daily liraglutide while 52% of new DPP4i users received metformin/DPP4i in fixed-dose. The percentage of new DPP4i users older than 65 years of age increased from 30.9 to 62.6% during the study period. Around 12% of new users had not received any antidiabetic before starting an incretin. CONCLUSIONS: During the study period, DPP4i rapidly became the most prescribed incretin-based medicine, particularly among older new user. The choice of the specific incretin-based medicine at first prescription appeared to be directed towards those with higher convenience of use (e.g. oral DPP4i rather than subcutaneous GLP1a, once-daily liraglutide rather than twice-daily exenatide). The non-negligibile use of incretin-based medicines as first-line pharmacotherapy for T2DM warrants further effectiveness and safety evaluations to better define their place in therapy.

The ENCePP Code of Conduct: A best practise for scientific independence and transparency in noninterventional postauthorisation studies.

PURPOSE: The ENCePP Code of Conduct provides a framework for scientifically independent and transparent pharmacoepidemiological research. Despite becoming a landmark reference, practical implementation of key provisions was still limited. The fourth revision defines scientific independence and clarifies uncertainties on the applicability to postauthorisation safety studies requested by regulators. To separate the influence of the funder from the investigator's scientific responsibility, the Code now requires that the lead investigator is not employed by the funding institution. METHOD: To assess how the revised Code fits the ecosystem of noninterventional pharmacoepidemiology research in Europe, we first mapped key recommendations of the revised Code against ISPE Good Pharmacoepidemiology Practices and the ADVANCE Code of Conduct. We surveyed stakeholders to understand perceptions on its value and practical applicability. Representatives from the different stakeholders' groups described their experience and expectations. RESULTS: Unmet needs in pharmacoepidemiological research are fulfilled by providing unique guidance on roles and responsibilities to support scientific independence. The principles of scientific independence and transparency are well understood and reinforce trust in study results; however, around 70% of survey respondents still found some provisions difficult to apply. Representatives from stakeholders' groups found the new version promising, although limitations still exist. CONCLUSION: By clarifying definitions and roles, the latest revision of the Code sets a new standard in the relationship between investigators and funders to support scientific independence of pharmacoepidemiological research. Disseminating and training on the provisions of the Code would help stakeholders to better understand its advantages and promote its adoption in noninterventional research.

Prescription of antiepileptic medicines including valproate in pregnant women: A study in three European countries.

PURPOSE: To study patterns of antiepileptic drugs (AED) prescribing, particularly valproate, during pregnancy over a 10-year period in the UK, Italy, and France. METHODS: Data on pregnancies conceived after 1 January 2007 with outcomes before 31 December 2016 were extracted from four European electronic health care databases (380 499 in the United Kingdom (UK), 66 681 in France, and 649 918 in Italy [355 767 in Emilia Romagna and 294 151 in Tuscany]). Prevalence of AEDs with an ATC code starting N03A and clobazam (N05BA09) were stratified by country and calendar year. RESULTS: AED prescribing during pregnancy varied from 3.0 (2.8-3.1) per 1000 pregnancies in Emilia Romagna to 7.8 (7.5-8.0) in the UK, 5.9 (5.6-6.1) in Tuscany, and 6.3 (5.7-6.9) in France. Lamotrigine was commonly prescribed in all regions with a third of women exposed to an AED during pregnancy taking lamotrigine in the UK and France. Valproate was prescribed to 28.6% of AED exposed pregnant women in Tuscany, 21.6% in France, 16.7% in Emilia Romagna, and 11.9% in the UK. Over the study period, the prevalence of AED prescribing increased in the UK mainly due to increases in pregabalin and gabapentin, declined in France mainly related to decreases in clonazepam, and remained constant in Italy. Valproate prescriptions declined to a prevalence <1 per 1000 pregnancies in 2015 to 2016 in the UK, France, and Emilia Romagna. CONCLUSIONS: Variations in AED prescribing during pregnancy indicate the potential for further reductions, particularly of valproate. Increases in pregabalin/gabapentin prescribing, for which risks are not well known, are a cause for concern.

Did advice on the prescription of sodium valproate reduce prescriptions to women? An observational study in three European countries between 2007 and 2016.

OBJECTIVES: In November 2014, the CMDh (a regulatory body representing EU Member States) advised doctors not to prescribe sodium valproate for epilepsy or bipolar disorder in preg nant women, in women who can become pregnant, or in girls unless other treatments are ineffective or not tolerated. This study aimed to determine if this warning led to changes in prescription patterns. DESIGN AND SETTING: Cohort of 5.4 million women aged between 10 and 50 years identified in electronic health care data from United Kingdom, France, and Italy (2007-2016). MAIN OUTCOME MEASURES: Anti-epileptic drug (AED) prescriptions. RESULTS: The prevalence of women receiving AED prescriptions in 2016 varied from 12.2 per 1000 to 29 per 1000 in the four regions. The incidence of prescribing any AED (excluding clonazepam, gabapentin, and pregabalin) fell each year on average by 7.5% (95% CI, 7.0%-8.0%; Emilia Romagna), 9.6% (8.3%-11.0%; France), 7.1% (6.7%-7.6%; Tuscany), and 0.4% (0.2%-1.0%; United Kingdom). The relative odds of prescribing sodium valproate rather than any other AED decreased more after 2014 compared with before the end of 2014 in France (OR = 0.77; 95% CI, 0.60-0.98), Tuscany (0.81; 0.76-0.86), Emilia Romagna (0.83; 0.76-0.90), and the United Kingdom (0.92; 0.80-1.06; not statistically significant). CONCLUSIONS: There is evidence that the CMDh warning did lead to changes in prescription patterns of sodium valproate in women of childbearing age. There were considerable differences in prescribing practice amongst regions of Europe.