Antidepressant use and stroke or mortality risk in the elderly.

BACKGROUND AND PURPOSE: Current evidence on antidepressant-related stroke or mortality risk is inconsistent. Because the elderly have the highest exposure to antidepressants, the aim was to quantify their association with stroke and mortality risks in this vulnerable population. METHODS: Persons over 65 years old and registered in the Information System for Research in Primary Care of Catalonia during 2010-2015 comprised the study population. Antidepressant exposure was categorized into current-users, recent-users, past-users and antidepressant non-users (controls). The effect of antidepressant exposure on stroke or death, whichever came first, was analyzed by Cox regression adjusted for established risk factors. RESULTS: Of the 1,068,117 participants included, 20% had antidepressant reimbursements during follow-up, 17% had a stroke and 3% died. The risk of experiencing stroke or death was higher in antidepressant current-users (hazard ratio [HR] 1.04; 95% confidence interval [CI] 1.02-1.06), recent-users (HR 3.34; 95% CI 3.27-3.41) and past-users (HR 2.06; 95% CI 2.02-2.10) compared to antidepressant non-users. Antidepressant current-use was associated with increased stroke (HR 1.56; 95% CI 1.50-1.61) but decreased mortality risk (HR 0.93; 95% CI 0.91-0.94). During antidepressant recent-use and past-use, both stroke and mortality risks were significantly increased compared to no antidepressant use. CONCLUSIONS: Antidepressant use may be associated with increased stroke risk in the elderly. When using antidepressants in this population, the potential risks should be considered.

Incidence of direct oral anticoagulant use in patients with nonvalvular atrial fibrillation and characteristics of users in 6 European countries (2008-2015): A cross-national drug utilization study.

AIMS: To estimate the incidence of direct oral anticoagulant drug (DOAC) use in patients with nonvalvular atrial fibrillation and to describe user and treatment characteristics in 8 European healthcare databases representing 6 European countries. METHODS: Longitudinal drug utilization study from January 2008 to December 2015. A common protocol approach was applied. Annual period incidences and direct standardisation by age and sex were performed. Dose adjustment related to change in age and by renal function as well as concomitant use of potentially interacting drugs were assessed. RESULTS: A total of 186 405 new DOAC users (age ≥18 years) were identified. Standardized incidences varied from 1.93-2.60 and 0.11-8.71 users/10 000 (2011-2015) for dabigatran and rivaroxaban, respectively, and from 0.01-8.12 users/10 000 (2012-2015) for apixaban. In 2015, the DOAC incidence ranged from 9 to 28/10 000 inhabitants in SIDIAP (Spain) and DNR (Denmark) respectively. There were differences in population coverage among the databases. Only 1 database includes the total reference population (DNR) while others are considered a population representative sample (CPRD, BIFAP, SIDIAP, EGB, Mondriaan). They also varied in the type of drug data source (administrative, clinical). Dose adjustment ranged from 4.6% in BIFAP (Spain) to 15.6% in EGB (France). Concomitant use of interacting drugs varied between 16.4% (SIDIAP) and 70.5% (EGB). Cardiovascular comorbidities ranged from 25.4% in Mondriaan (The Netherlands) to 82.9% in AOK Nordwest (Germany). CONCLUSION: Overall, apixaban and rivaroxaban increased its use during the study period while dabigatran decreased. There was variability in patient characteristics such as comorbidities, potentially interacting drugs and dose adjustment. (EMA/2015/27/PH).

Association of Liver Injury From Specific Drugs, or Groups of Drugs, With Polymorphisms in HLA and Other Genes in a Genome-Wide Association Study.

BACKGROUND & AIMS: We performed a genome-wide association study (GWAS) to identify genetic risk factors for drug-induced liver injury (DILI) from licensed drugs without previously reported genetic risk factors. METHODS: We performed a GWAS of 862 persons with DILI and 10,588 population-matched controls. The first set of cases was recruited before May 2009 in Europe (n = 137) and the United States (n = 274). The second set of cases were identified from May 2009 through May 2013 from international collaborative studies performed in Europe, the United States, and South America. For the GWAS, we included only cases with patients of European ancestry associated with a particular drug (but not flucloxacillin or amoxicillin-clavulanate). We used DNA samples from all subjects to analyze HLA genes and single nucleotide polymorphisms. After the discovery analysis was concluded, we validated our findings using data from 283 European patients with diagnosis of DILI associated with various drugs. RESULTS: We associated DILI with rs114577328 (a proxy for A*33:01 a HLA class I allele; odds ratio [OR], 2.7; 95% confidence interval [CI], 1.9-3.8; P = 2.4 × 10-8) and with rs72631567 on chromosome 2 (OR, 2.0; 95% CI, 1.6-2.5; P = 9.7 × 10-9). The association with A*33:01 was mediated by large effects for terbinafine-, fenofibrate-, and ticlopidine-related DILI. The variant on chromosome 2 was associated with DILI from a variety of drugs. Further phenotypic analysis indicated that the association between DILI and A*33:01 was significant genome wide for cholestatic and mixed DILI, but not for hepatocellular DILI; the polymorphism on chromosome 2 was associated with cholestatic and mixed DILI as well as hepatocellular DILI. We identified an association between rs28521457 (within the lipopolysaccharide-responsive vesicle trafficking, beach and anchor containing gene) and only hepatocellular DILI (OR, 2.1; 95% CI, 1.6-2.7; P = 4.8 × 10-9). We did not associate any specific drug classes with genetic polymorphisms, except for statin-associated DILI, which was associated with rs116561224 on chromosome 18 (OR, 5.4; 95% CI, 3.0-9.5; P = 7.1 × 10-9). We validated the association between A*33:01 terbinafine- and sertraline-induced DILI. We could not validate the association between DILI and rs72631567, rs28521457, or rs116561224. CONCLUSIONS: In a GWAS of persons of European descent with DILI, we associated HLA-A*33:01 with DILI due to terbinafine and possibly fenofibrate and ticlopidine. We identified polymorphisms that appear to be associated with DILI from statins, as well as 2 non-drug-specific risk factors.

Only full adherence to proton pump inhibitors protects against drug-induced upper gastrointestinal bleeding.

PURPOSE: The use of gastroprotective agents has allowed significant progress in the prevention of upper gastrointestinal bleeding (UGIB) associated with non-steroidal anti-inflammatory drugs (NSAIDs) and antiplatelet agents. Nevertheless, some concerns remain regarding the gastroprotective dosage and treatment duration. Our aim was to study the effect of gastroprotective agents in UGIB induced by NSAIDs and single- or dual-antiplatelet therapy. METHODS: A multicenter case-control study was conducted including 577 cases diagnosed with UGIB and 1343 sex-, age-, and hospital-matched controls. To estimate exposure to NSAIDs and gastroprotective agents, consumption was calculated for the 4 weeks prior to hospital admission in terms of defined daily doses (DDDs). Risk groups for UGIB induced by NSAIDs and single- or dual-antiplatelet therapy were defined as a function of each drug dose, use of gastrointestine-damaging drugs, and risk factors for UGIB. Odds ratios (ORs) with 95% confidence intervals (CIs) were adjusted for single- (model 1) and dual- (model 2) antiplatelet therapy. RESULTS: Full adherence (> 0.80DDD) to proton pump inhibitors (PPIs) was the only gastroprotective therapy that significantly reduced the risk of UGIB, considering NSAID risk (OR: 0.53; 95% CI: 0.30-0.95) and dose (OR: 0.48; 95% CI: 0.27-0.87) with ORs adjusted for single-antiplatelet therapy (model 1) and NSAID risk (OR: 0.55; 95% CI: 0.31-0.98) and dose (OR: 0.49; 95% CI: 0.28-0.89) with ORs adjusted for dual-antiplatelet therapy (model 2). CONCLUSIONS: These results reinforce the recommendation of adding a PPI at effective doses (full adherence) to prevent UGIB induced by NSAIDs, or single- or dual-antiplatelet therapy.

CYP2C9 variants as a risk modifier of NSAID-related gastrointestinal bleeding: a case-control study.

OBJECTIVE: The aim of this study was to assess whether the CYP2C9*2 and/or *3 variants might modify the risk for NSAID-related upper gastrointestinal bleeding (UGIB) in NSAID users. PATIENTS AND METHODS: We conducted a multicenter, case-control study in which cases were patients aged more than 18 years with a diagnosis of UGIB, and controls were matched (1 : 3) by sex, age, date of admission, and hospital. Exposure was defined as the mean number of defined daily doses (DDDs) of NSAIDs metabolized by CYP2C9 in the week preceding the index date. Three DDD categories were defined (0, ≤ 0.5, and > 0.5). Exposure was constructed taking both NSAID use and CYP2C9 polymorphisms into account. Patients of non-European origin were excluded from the analysis. RESULTS: A total of 577 cases and 1343 controls were finally included in the analysis: 103 cases and 89 controls consumed NSAIDs metabolized by CYP2C9, and 88 cases and 177 controls were CYP2C9*3 carriers. The adjusted odds ratios (aORs) of UGIB associated with the CYP2C9*2 and wild-type alleles proved to be similar [OR=8.79 (4.50-17.17) and 10.15 (2.92-35.35), respectively] and lower than those of the CYP2C9*3 allele [aOR=18.07 (6.34-51.53)] for consumers taking more than 0.5 DDDs of NSAIDs metabolized by CYP2C9. Grouping genotypes into carriers and noncarriers of the CYP2C9*3 variant resulted in aORs of 16.92 (4.96-57.59) for carriers and 9.72 (4.55-20.76) for noncarriers, where DDDs were greater than 0.5. CONCLUSION: The presence of the CYP2C9*3 variant increases the risk for UGIB associated with NSAID for DDDs greater than 0.5. The presence of the CYP2C9*2 allele shows no such effect.

Tiotropium Respimat(®) vs. HandiHaler(®): real-life usage and TIOSPIR trial generalizability.

AIM: Two inhaler devices (Respimat® and HandiHaler®) are available for tiotropium, a long acting anticholinergic agent. We aimed to analyze drug utilization, off-label usage and generalizability of the TIOSPIR trial results for both devices. METHODS: Patients aged ≥18 years exhibiting at least one documented prescription of tiotropium in the database of the Association of Statutory Health Insurance Physicians, Bavaria, Germany, were included (years 2004-2008). Annual period prevalence rates (PPRs) were calculated stratified by age, gender and inhaler devices. Off-label usage (patients lacking a chronic obstructive pulmonary disease (COPD) diagnosis) and the proportion of patients meeting the inclusion and exclusion criteria of the TIOSPIR trial were analyzed. RESULTS: Between 2004 and 2008, PPRs increased and varied between 49.2 and 74.5 per 10 000 persons for HandiHaler® and between 1.5 and 9.3 per 10 000 persons for Respimat®. Small differences regarding patient characteristics existed between the two inhaler devices. Only about 30% (HandiHaler® 32.1%, Respimat® 30.0%) of the database patients receiving tiotropium could be theoretically included in the TIOSPIR trial. CONCLUSIONS: Comparing the two tiotropium devices, no clinically relevant differences regarding patient and prescribing characteristics were revealed. Results of the TIOSPIR trial were generalizable only to a minority of our study patients, underlining the need for real-life data.

Multi-centre, multi-database studies with common protocols: lessons learnt from the IMI PROTECT project.

PURPOSE: To assess the impact of a variety of methodological parameters on the association between six drug classes and five key adverse events in multiple databases. METHODS: The selection of Drug-Adverse Event pairs was based on public health impact, regulatory relevance, and the possibility to study a broad range of methodological issues. Common protocols and data analytical specifications were jointly developed and independently and blindly executed in different databases in Europe with replications in the same and different databases. RESULTS: The association between antibiotics and acute liver injury, benzodiazepines and hip fracture, antidepressants and hip fracture, inhaled long-acting beta2-agonists and acute myocardial infarction was consistent in direction across multiple designs, databases and methods to control for confounding. Some variation in magnitude of the associations was observed depending on design, exposure and outcome definitions, but none of the differences were statistically significant. The association between anti-epileptics and suicidality was inconsistent across the UK CPRD, Danish National registries and the French PGRx system. Calcium channel blockers were not associated with the risk of cancer in the UK CPRD, and this was consistent across different classes of calcium channel blockers, cumulative durations of use up to >10 years and different types of cancer. CONCLUSIONS: A network for observational drug effect studies allowing the execution of common protocols in multiple databases was created. Increased consistency of findings across multiple designs and databases in different countries will increase confidence in findings from observational drug research and benefit/risk assessment of medicines.

Prescribing of long-acting beta-2-agonists/inhaled corticosteroids after the SMART trial.

BACKGROUND: After the SMART trial evaluating the safety of salmeterol (long-acting beta-2-agonist (LABA)) in asthma patients, regulatory actions were taken to promote a guideline-adherent prescribing of LABA only to patients receiving inhaled corticosteroids (ICS). We aim to analyse LABA- and ICS-related prescription patterns after the SMART trial in Germany. METHODS: Patients documented in the Bavarian Association of Statutory Health Insurance Physicians database (approximately 10.5 million people) were included if they had a diagnosis of asthma and at least one prescription of LABA and/or ICS between 2004 and 2008. Annual period prevalence rates (PPRs) were estimated and Cochrane Armitage tests were used for time trend analyses. RESULTS: Highest annual PPRs were found for budesonide and the fixed combination of salmeterol/fluticasone. The proportion of "concomitant LABA and ICS users" increased from 52.0 to 57.6% within the study period, whereas for "LABA users without ICS" a slight decrease from 6.5 to 5.4% was found. In 2008, the proportion of patients with at least one quarter with a LABA prescription without concomitant ICS was highest in elderly, male patients (≈20%). In the majority of these patients, a concomitant diagnosis of COPD (i.e. asthma-COPD overlap syndrome [ACOS]) was present. CONCLUSIONS: Between 2004 and 2008, we found a moderate increase in guideline-adherent LABA prescribing in a representative German population. Elderly men received a significant number of LABA prescriptions without concomitant ICS probably due to ACOS.

Antiepileptic drugs and suicide: a systematic review of adverse effects.

BACKGROUND: Since the FDA (Food and Drug Administration) report on antiepileptic drugs (AEDs) and suicide risk was released (2008), several studies have been published on this controversial relationship. This systematic review (SR) gives an updated approach to this health issue. SUMMARY: We searched 6 databases. We ultimately included 11 publications: 4 cohort studies, 1 case-crossover study, 2 community case-control studies, and 4 SRs. Overall, 1 SR described studies already included; 3 studies reported a 2- to 4-fold overall increase in risk; 1 study reported an increased risk of suicide among epilepsy patients on AEDs with high risk of depression; 1study showed a protective effect among epilepsy patients; 2 studies were conducted with patients with bipolar disorder (1 showed a protective effect, whereas the other showed a 3-fold increase in risk of suicide), and the other 3 studies reported results for single AEDs. Several biases affected the published results. KEY MESSAGES: There is no clear evidence of an association between the use of AEDs and an increased risk of suicide because of the heterogeneity in the studies at the clinical and methodological level. A future study should cover all indications for use, retrieve information from a healthcare database, and include a defined set of covariates to avoid bias.

Impact of 2018 EU Risk Minimisation Measures and Revised Pregnancy Prevention Programme on Utilisation and Prescribing Trends of Medicinal Products Containing Valproate: An Interrupted Time Series Study.

INTRODUCTION: Due to established teratogenicity of valproates, the EU risk minimisation measures (RMMs) with a pregnancy prevention programme (PPP) for valproate were updated in March 2018. OBJECTIVES: To investigate the effectiveness of the 2018 EU RMMs on valproate utilisation in five European countries/regions. METHODS: A multi-database, times series study of females of childbearing potential (12-55 years) was conducted using electronic medical records from five countries/regions (01.01.2010-31.12.2020): Denmark, Tuscany (Italy), Spain, the Netherlands, and the UK. Clinical and demographic information from each database was transformed to the ConcePTION Common Data Model, quality checks were conducted and a distributed analysis was performed using common scripts. Incident and prevalent use of valproate, proportion of discontinuers and switchers to alternative medicine, frequency of contraception coverage during valproate use, and occurrence of pregnancies during valproate exposure were estimated per month. Interrupted time series analyses were conducted to estimate the level or trend change in the outcome measures. RESULTS: We included 69,533 valproate users from 9,699,371 females of childbearing potential from the five participating centres. A significant decline in prevalent use of valproates was observed in Tuscany, Italy (mean difference post-intervention -7.7%), Spain (-11.3%), and UK (-5.9%) and a non-significant decline in the Netherlands (-3.3%), but no decline in incident use after the 2018 RMMs compared to the period before. The monthly proportion of compliant valproate prescriptions/dispensings with a contraceptive coverage was low (<25%), with an increase after the 2018 RMMs only in the Netherlands (mean difference post-intervention 12%). There was no significant increase in switching rates from valproates to alternative medicine after the 2018 intervention in any of the countries/regions. We observed a substantial number of concurrent pregnancies during valproate exposure, but with a declining rate after the 2018 RMMs in Tuscany, Italy (0.70 per 1000 valproate users pre- and 0.27 post-intervention), Spain (0.48 and 0.13), the Netherlands (0.34 and 0.00), and an increasing rate in UK (1.13 and 5.07). CONCLUSION: There was a small impact of the 2018 RMMs on valproate use in the studied European countries/regions. The substantial number of concurrent pregnancies with valproate exposure warrants a careful monitoring of implementation of the existing PPP for valproate in clinical practice in Europe, to see if there is any need for additional measures in the future.

Impact of the 2018 revised Pregnancy Prevention Programme by the European Medicines Agency on the use of oral retinoids in females of childbearing age in Denmark, Italy, Netherlands, and Spain: an interrupted time series analysis.

Background: In March 2018, the European pregnancy prevention programme for oral retinoids was updated as part of risk minimisation measures (RMM), emphasising their contraindication in pregnant women. Objective: To measure the impact of the 2018 revision of the RMMs in Europe by assessing the utilisation patterns of isotretinoin, alitretinoin and acitretin, contraceptive measures, pregnancy testing, discontinuation, and pregnancy occurrence concomitantly with a retinoid prescription. Methods: An interrupted time series (ITS) analysis to compare level and trend changes after the risk minimisation measures implementation was conducted on a cohort of females of childbearing age (12-55 years of age) from January 2010 to December 2020, derived from six electronic health data sources in four countries: Denmark, Netherlands, Spain, and Italy. Monthly utilisation figures (incidence rates [IR], prevalence rates [PR] and proportions) of oral retinoids were calculated, as well as discontinuation rates, contraception coverage, pregnancy testing, and rates of exposed pregnancies to oral retinoids, before and after the 2018 RMMs. Results: From 10,714,182 females of child-bearing age, 88,992 used an oral retinoid at any point during the study period (mean age 18.9-22.2 years old). We found non-significant level and trend changes in incidence or prevalence of retinoid use in females of child-bearing age after the 2018 RMMs. The reason of discontinuation was unknown in >95% of cases. Contraception use showed a significant increase trend in Spain; for other databases this information was limited. Pregnancy testing was hardly recorded thus was not possible to model ITS analyses. After the 2018 RMM, rates of pregnancy occurrence during retinoid use, and start of a retinoid during a pregnancy varied from 0.0 to 0.4, and from 0.2 to 0.8, respectively. Conclusion: This study shows a limited impact of the 2018 RMMs on oral retinoids utilisation patterns among females of child-bearing age in four European countries. Pregnancies still occur during retinoid use, and oral retinoids are still prescribed to pregnant women. Contraception and pregnancy testing information was limited in most databases. Regulators, policymakers, prescribers, and researchers must rethink implementation strategies to avoid any pregnancy becoming temporarily related to retinoid use.

Susceptibility to amoxicillin-clavulanate-induced liver injury is influenced by multiple HLA class I and II alleles.

BACKGROUND & AIMS: Drug-induced liver injury (DILI), especially from antimicrobial agents, is an important cause of serious liver disease. Amoxicillin-clavulanate (AC) is a leading cause of idiosyncratic DILI, but little is understood about genetic susceptibility to this adverse reaction. METHODS: We performed a genome-wide association study using 822,927 single nucleotide polymorphism (SNP) markers from 201 White European and US cases of DILI following AC administration (AC-DILI) and 532 population controls, matched for genetic background. RESULTS: AC-DILI was associated with many loci in the major histocompatibility complex. The strongest effect was with an HLA class II SNP (rs9274407, P=4.8×10(-14)), which correlated with rs3135388, a tag SNP of HLA-DRB1*1501-DQB1*0602 that was previously associated with AC-DILI. Conditioned on rs3135388, rs9274407 is still significant (P=1.1×10(-4)). An independent association was observed in the class I region (rs2523822, P=1.8×10(-10)), related to HLA-A*0201. The most significant class I and II SNPs showed statistical interaction (P=.0015). High-resolution HLA genotyping (177 cases and 219 controls) confirmed associations of HLA-A*0201 (P=2×10(-6)) and HLA-DQB1*0602 (P=5×10(-10)) and their interaction (P=.005). Additional, population-dependent effects were observed in HLA alleles with nominal significance. In an analysis of autoimmune-related genes, rs2476601 in the gene PTPN22 was associated (P=1.3×10(-4)). CONCLUSIONS: Class I and II HLA genotypes affect susceptibility to AC-DILI, indicating the importance of the adaptive immune response in pathogenesis. The HLA genotypes identified will be useful in studies of the pathogenesis of AC-DILI but have limited utility as predictive or diagnostic biomarkers because of the low positive predictive values.

Potential impact of benzodiazepine use on the rate of hip fractures in five large European countries and the United States.

Benzodiazepine use increases the risk of falls and has been associated with an increased risk of hip fractures. Our aim was to estimate the possible population impact of the use of benzodiazepines on the rate of hip fracture in France, Germany, Italy, Spain, the United Kingdom, and the United States. We conducted a literature review to estimate the pooled relative risk (RR) for hip fractures and use of benzodiazepines. Prevalence rates of benzodiazepine use in 2009 were calculated for each country using the IMS MIDAS database and three public databases in Denmark, the Netherlands, and Norway. Both the RR and prevalence rates were used for calculation of population attributable risks (PARs) of hip fractures associated with benzodiazepine use. The literature review showed an increased risk of hip fractures in benzodiazepine users (RR = 1.4, 95 % CI 1.2-1.6). Rate of benzodiazepine use showed considerable differences between countries, ranging from 4.7 % to 22.3 % of population ever in a 1-year period. These are reflected in results for the PARs; estimated attributions of benzodiazepines to the rate of hip fractures were 1.8 %, 95 % CI 1.1-2.6 (Germany); 2.0 %, 95 % CI 1.2-2.8 (United Kingdom); 5.2 %, 95 % CI 3.2-7.3 (Italy); 7.4 %, 95 % CI 4.5-10.0 (France); 8.0 %, 95 % CI 4.9-11.0 (United States); and 8.2 %, 95 % CI 5.1-12.0 (Spain). PAR estimates suggest that the potential attribution of benzodiazepine use on the population rate of hip fractures in the five specified European countries and the United States varies between 1.8 % and 8.2 %. During the next phase of the IMI-PROTECT study, a comparison with individual patient data will show whether this approach is valid.

Synergism interaction between genetic polymorphisms in drug metabolizing enzymes and NSAIDs on upper gastrointestinal haemorrhage: a multicenter case-control study.

BACKGROUND: Interindividual genetic variations contribute to differences in patients' response to drugs as well as to the development of certain disorders. Patients who use non-steroidal anti-inflammatory drugs (NSAIDs) may develop serious gastrointestinal disorders, mainly upper gastrointestinal haemorrhage (UGIH). Studies about the interaction between NSAIDs and genetic variations on the risk of UGIH are scarce. Therefore, we investigated the effect of 16 single nucleotide polymorphisms (SNPs) involved in drug metabolism on the risk of NSAIDs-induced UGIH. MATERIALS AND METHODS: We conducted a multicenter case-control study of 326 cases and 748 controls. Participants were sub-grouped into four categories according to NSAID exposure and genetic profile. We estimated odds ratios (ORs) and their 95% confidence intervals (CI) using generalized linear mixed models for dependent binomial variables and then calculated the measures of interaction, synergism index (S), and relative excess risk due to interaction (RERI). We undertook stratified analyses by the type of NSAID (aspirin, non-aspirin). RESULTS: We observed an excess risk of UGIH due to an interaction between any NSAID, non-aspirin NSAIDs or aspirin and carrying certain SNPs. The greatest excess risk was observed for carriers of: rs2180314:C>G [any NSAID: S = 3.30 (95%CI: 1.24-8.80), RERI = 4.39 (95%CI: 0.70-8.07); non-aspirin NSAIDs: S = 3.42 (95%CI: 1.12-10.47), RERI = 3.97 (95%CI: 0.44-7.50)], and rs4809957:A>G [any NSAID: S = 2.11 (95%CI: 0.90-4.97), RERI = 3.46 (95%CI: -0.40-7.31)]. Aspirin use by carriers of rs6664:C>T is also associated with increased risk of UGIH [ORaspirin(+),wild-type: 2.22 (95%CI: 0.69-7.17) vs. ORaspirin(+),genetic-variation: 7.72 (95%CI: 2.75-21.68)], yet larger sample size is needed to confirm this observation. CONCLUSIONS: The joint effect of the SNPs s2180314:C>G and rs4809957:A>G and NSAIDs are more than three times higher than the sum of their individual effects. Personalized prescriptions based on genotyping would permit a better weighing of risks and benefits from NSAID consumption.KEY MESSAGESMulticenter case-control study of the effect of genetic variations involved in drug metabolism on upper gastrointestinal haemorrhage (UGIH) induced by NSAIDs (aspirin and non-aspirin).There is a statistically significant additive synergism interaction between certain genetic polymorphisms and NSAIDs on UGIH: rs2180314:C>G and rs4809957:A>G. The joint effect of each of these single nucleotide polymorphisms and NSAIDs on UGIH is more than three times higher than the sum of their individual effects.Genetic profiling and personalized prescriptions would be useful in managing the risks and benefits associated with NSAIDs.

Paracetamol in therapeutic dosages and acute liver injury: causality assessment in a prospective case series.

BACKGROUND: Acute liver injury (ALI) induced by paracetamol overdose is a well known cause of emergency hospital admission and death. However, there is debate regarding the risk of ALI after therapeutic dosages of the drug.The aim is to describe the characteristics of patients admitted to hospital with jaundice who had previous exposure to therapeutic doses of paracetamol. An assessment of the causality role of paracetamol was performed in each case. METHODS: Based on the evaluation of prospectively gathered cases of ALI with detailed clinical information, thirty-two cases of ALI in non-alcoholic patients exposed to therapeutic doses of paracetamol were identified. Two authors assessed all drug exposures by using the CIOMS/RUCAM scale. Each case was classified into one of five categories based on the causality score for paracetamol. RESULTS: In four cases the role of paracetamol was judged to be unrelated, in two unlikely, and these were excluded from evaluation. In seven of the remaining 26 cases, the RUCAM score associated with paracetamol was higher than that associated with other concomitant medications. The estimated incidence of ALI related to the use of paracetamol in therapeutic dosages was 0.4 per million inhabitants older than 15 years of age and per year (99%CI, 0.2-0.8) and of 10 per million paracetamol users-year (95% CI 4.3-19.4). CONCLUSIONS: Our results indicate that paracetamol in therapeutic dosages may be considered in the causality assessment in non-alcoholic patients with liver injury, even if the estimated incidence of ALI related to paracetamol appears to be low.

Factors associated with primary nonadherence to newly initiated direct oral anticoagulants in patients with nonvalvular atrial fibrillation.

BACKGROUND: Direct oral anticoagulants (DOACs) are widely used for the prevention of stroke in nonvalvular atrial fibrillation (NVAF); however, real-world primary nonadherence (failing to collect the first prescription) has been measured in very few studies. OBJECTIVE: To report primary nonadherence in NVAF patients who are newly prescribed DOACs and identify associated factors. METHODS: This observational retrospective cohort study used a large primary care database in Catalonia. Patients with NVAF who were newly prescribed a DOAC between January 2009 and December 2015 were identified, and primary nonadherence was measured by comparing prescribing records to pharmacy claims data. Multivariable logistic regression was used to determine associated factors. RESULTS: A total of 12,257 patients met the inclusion and exclusion criteria; of these, 1,276 (10.4%) were primary nonadherent. Primary nonadherence was found to be 12.8% for apixaban, 8.6% for dabigatran, and 10.8% for rivaroxaban. Multivariable logistic regression indicated higher odds of primary nonadherence with apixaban and rivaroxaban compared to dabigatran (apixaban: OR = 1.61, 95% CI = 1.39-1.87; rivaroxaban: OR = 1.28, 95% CI = 1.11-1.47). Patients aged at least 80 years showed lower odds of primary nonadherence compared to those aged less than 65 years (OR = 0.78, 95% CI = 0.66-0.93). A diagnosis of chronic kidney disease was associated with primary nonadherence (OR = 1.27, 95% CI = 1.08-1.50). Whereas, diabetes (OR = 0.85, 95% CI = 0.74-0.97), hypertension (OR = 0.79, 95% CI = 0.70-0.91), and stroke/transient ischemic attack (OR = 0.70, 95% C I =0.59-0.82) were inversely associated with primary nonadherence. CONCLUSIONS: Overall, 10.4% of patients prescribed DOACs were primary nonadherent, failing to collect the first prescription. The percentage could have serious implications for patient outcomes and the real-world cost-effectiveness of prescribing DOACs in NVAF. Rates of primary nonadherence and associated factors may provide useful information for the design and evaluation of adherence interventions. DISCLOSURES: No outside funding was received for this study. The data for this study came from the European Medicines Agency PE-PV project (Grant/Award Number EMA/2015/27/PH). The authors have nothing to disclose. A preliminary version of this work was presented at the European Drug Utilisation Research Group (EuroDURG) Conference, Szeged, Hungary, March 5, 2020.

A multicenter case-control study of the effect of e-nos VNTR polymorphism on upper gastrointestinal hemorrhage in NSAID users.

Bleeding in non-steroidal anti-inflammatory drug (NSAID) users limited their prescription. This first multicenter full case-control study (325 cases and 744 controls), explored the association of e-NOS intron 4 variable number tandem repeat (VNTR) polymorphism with upper gastrointestinal hemorrhage (UGIH) in NSAID exposed and unexposed populations and assessed any interaction between this polymorphism and NSAIDs. NSAID users carrying e-NOS intron 4 wild type genotype or VNTR polymorphism have higher odds of UGIH than those unexposed to NSAIDs [Odds Ratio (OR): 6.62 (95% Confidence Interval (CI): 4.24, 10.36) and OR: 5.41 (95% CI 2.62, 11.51), respectively], with no effect modification from VNTR polymorphism-NSAIDs interaction [Relative Excess Risk due to Interaction (RERI): -1.35 (95% CI -5.73, 3.03); Synergism Index (S): 0.77 (95% CI 0.31, 1.94)]. Similar findings were obtained for aspirin exposure. Non-aspirin NSAID users who carry e-NOS intron 4 VNTR polymorphism have lower odds of UGIH [OR: 4.02 (95% CI 1.85, 8.75) than those users with wild type genotype [OR: 6.52 (95% CI 4.09, 10.38)]; though the interaction estimates are not statistically significant [RERI: -2.68 (95% CI -6.67, 1.31); S: 0.53 (95% CI 0.18, 1.55)]. This exploratory study suggests that the odds of UGIH in NSAID or aspirin users does not modify according to patient´s e-NOS intron 4 genotype.

Prescribers' compliance with summary of product characteristics of dabigatran, rivaroxaban and apixaban-A European comparative drug utilization study.

Despite a tremendous increase of direct oral anticoagulants (DOACs) prescriptions in recent years, only few data is available analysing prescribers' adherence to Summary of Product Characteristics (SmPC). We aimed to assess adherence to registered indications, contraindications, special warnings/precautions, and potential drug-drug interactions for three DOAC compounds (dabigatran, rivaroxaban, and apixaban) in six databases of five European countries (The Netherlands, United Kingdom, Spain, Denmark, and Germany). We included adult patients (≥18 years) initiating DOACs between 2008 and 2015. For several SmPC items, broad definitions were used due to ambiguous SmPC terms or lacking data in some databases. Within the study period, a DOAC was initiated in 407 576 patients (rivaroxaban: 240 985 (59.1%), dabigatran: 95 303 (23.4%), and apixaban: 71 288 (17.5%)). In 2015, non-valvular atrial fibrillation was the most common indication (>60% in most databases). For the whole study period, a substantial variation between the databases was found regarding the proportion of patients with at least one contraindication (inter-database range [IDR]: 8.2%-55.7%), with at least one special warning/precaution (IDR: 35.8%-75.2%) and with at least one potential drug-drug interaction (IDR: 22.4%-54.1%). In 2015, the most frequent contraindication was "malignant neoplasm" (IDR: 0.7%-21.3%) whereas the most frequent special warning/precaution was "prescribing to the elderly" (≥75 years; IDR: 25.0%-66.4%). The most common single compound class interaction was "concomitant use of non-steroidal anti-inflammatory drugs" (IDR: 3.0%-25.3%). Contraindications, special warnings/precautions, and potential drug-drug interactions were present in a relevant number of new DOAC users. Due to broad definitions used for some SmPC terms, overall proportions for contraindications are prone to overestimation. However, for unambiguous SmPC terms documented in the databases sufficiently, the respective estimates can be considered valid. Differences between databases might be related to "true" differences in prescription behaviour, but could also be partially due to differences in database characteristics.

Genetic Risk Factors in Drug-Induced Liver Injury Due to Isoniazid-Containing Antituberculosis Drug Regimens.

Drug-induced liver injury (DILI) is a complication of treatment with antituberculosis (TB) drugs, especially in isoniazid (INH)-containing regimens. To investigate genetic risk factors, we performed a genomewide association study (GWAS) involving anti-TB DILI cases (55 Indian and 70 European) and controls (1,199 Indian and 10,397 European). Most cases were treated with a standard anti-TB drug regimen; all received INH. We imputed single nucleotide polymorphism and HLA genotypes and performed trans-ethnic meta-analysis on GWAS and candidate gene genotypes. GWAS found one significant association (rs117491755) in Europeans only. For HLA, HLA-B*52:01 was significant (meta-analysis odds ratio (OR) 2.67, 95% confidence interval (CI) 1.63-4.37, P = 9.4 × 10-5 ). For N-acetyltransferase 2 (NAT2), NAT2*5 frequency was lower in cases (OR 0.69, 95% CI 0.57-0.83, P = 0.01). NAT2*6 and NAT2*7 were more common, with homozygotes for NAT2*6 and/or NAT2*7 enriched among cases (OR 1.89, 95% CI 0.84-4.22, P = 0.004). We conclude HLA genotype makes a small contribution to TB drug-related DILI and that the NAT2 contribution is complex, but consistent with previous reports when differences in the metabolic effect of NAT2*5 compared with those of NAT2*6 and NAT2*7 are considered.

High-Throughput Sequencing to Investigate Associations Between HLA Genes and Metamizole-Induced Agranulocytosis.

Background and Objective: Agranulocytosis is a rare and potentially life-threatening complication of metamizole (dipyrone) intake that is characterized by a loss of circulating neutrophil granulocytes. While the mechanism underlying this adverse drug reaction is not well understood, involvement of the immune system has been suggested. In addition, associations between genetic variants in the Human Leukocyte Antigen (HLA) region and agranulocytosis induced by other drugs have been reported. The aim of the present study was to assess whether genetic variants in classical HLA genes are associated with the susceptibility to metamizole-induced agranulocytosis (MIA) in a European population by targeted resequencing of eight HLA genes. Design: A case-control cohort of Swiss patients with a history of neutropenia or agranulocytosis associated with metamizole exposure (n = 53), metamizole-tolerant (n = 39) and unexposed controls (n = 161) was recruited for this study. A high-throughput resequencing (HTS) and high-resolution typing method was used to sequence and analyze eight HLA loci in a discovery subset of this cohort (n = 31 cases, n = 38 controls). Identified candidate alleles were investigated in the full Swiss cohort as well as in two independent cohorts from Germany and Spain using HLA imputation from genome-wide SNP array data. In addition, variant calling based on HTS data was performed in the discovery subset for the class I genes HLA-A, -B, and -C using the HLA-specific mapper hla-mapper. Results: Eight candidate alleles (p < 0.05) were identified in the discovery subset, of which HLA-C∗04:01 was associated with MIA in the full Swiss cohort (p < 0.01) restricted to agranulocytosis (ANC < 0.5 × 109/L) cases. However, no candidate allele showed a consistent association in the Swiss, German and Spanish cohorts. Analysis of individual sequence variants in class I genes produced consistent results with HLA typing but did not reveal additional small nucleotide variants associated with MIA. Conclusion: Our results do not support an HLA-restricted T cell-mediated immune mechanism for MIA. However, we established an efficient high-resolution (three-field) eight-locus HTS HLA resequencing method to interrogate the HLA region and demonstrated the feasibility of its application to pharmacogenetic studies.