Base de Datos para la Investigación Farmacoepidemiológica en Atención Primaria (BIFAP): A data resource for pharmacoepidemiology in Spain

Risk of agranulocytosis with metamizole in comparison with alternative medications based on health records in Spain

PURPOSE

We aimed to estimate the absolute (incidence) and relative (hazard ratio; HR) risk of agranulocytosis associated with metamizole in comparison with non-steroidal antiinflammatory drugs (NSAIDs).

METHODS

A cohort study of new users of metamizole versus NSAIDs was performed with BIFAP (Pharmacoepidemiologic Research Database in Public Health Systems; Spain). Patients aged ≥ 2 years in 2005-2022 were followed up from the day after their first metamizole or NSAID dispensation till the end of the treatment period to identify patients hospitalized due to idiosyncratic agranulocytosis. Incidence rate (IR) and adjusted HR of agranulocytosis with metamizole versus NSAID were estimated assuming the onset date of agranulocytosis was the date of hospitalization sensitivity analysis or 7 days before (main analysis). In secondary analyses, we used (1) opioids-paracetamol as negative control and (2) any hospitalized neutropenia as outcome (assuming the onset was 7 days before).

RESULTS

The cohorts included 444,972 new users of metamizole, 3,814,367 NSAID, and 3,129,221 opioids-paracetamol on continuous treatment during a median of 37-40 days. Overall, 26 hospitalized agranulocytosis occurred, 5 in the first week (and so removed in main analysis) and 21 thereafter. IR of agranulocytosis was 14.20 (N = 5 cases) and 8.52 (N = 3), 1.95 (N = 6) and 1.62 (N = 5), and 4.29 (N = 15) and 3.72 (N = 13)/107 person-weeks of continuous treatment using the date of hospitalization or 7 days before, respectively. Two, 0 and 2 of cases identified in both analyses had neoplasia in every cohort, respectively. HR of agranulocytosis associated with metamizole was 7.20 [95% CI: 1.92-26.99] and 4.40 [0.90-21.57] versus NSAID, and 3.31 [1.17-9.34] and 2.45 [0.68-8.83] versus opioid-paracetamol, respectively. HR of neutropenia with metamizole was 2.98 [1.57-5.65] versus NSAID.

CONCLUSIONS

Agranulocytosis was very rare but more common (above 4 times more) with metamizole than other analgesics. The impact of the drug-induced agranulocytosis was less precise with metamizole than the comparators due to its lower use, which precluded to find statistical differences in main analysis. The increased risk of hospitalized neutropenias with metamizole supports the link with its severity although triggers unavailable during the follow-up (ex. cytotoxic medication) can not be discarded.

Antithrombotic Use Patterns in COVID-19 Patients from Spain: A Real-World Data Study

Antithrombotics have been widely used to treat and prevent COVID-19-related thrombosis; however, studies on their use at population levels are limited. We aimed to describe antithrombotic use patterns during the pandemic in Spanish primary care and hospital-admitted patients with COVID-19. Methods: A real-world data study was performed. Data were obtained from BIFAP's electronic health records. We investigated the antithrombotic prescriptions made within ±14 days after diagnosis between March 2020 and February 2022, divided their use into prior and new/naive groups, and reported their post-discharge use. Results: We included 882,540 individuals (53.4% women), of whom 78,499 were hospitalized. The median age was 44.7 (IQR 39-59). Antithrombotics were prescribed in 37,183 (4.6%) primary care subjects and 42,041 (53.6%) hospital-admitted patients, of whom 7505 (20.2%) and 20,300 (48.3%), respectively, were naive users. Prior users were older and had more comorbidities than new users. Enoxaparin was the most prescribed antithrombotic in hospitals, with higher prescription rates in new than prior users (2348.2, IQR 2390-3123.1 vs. 1378, IQR 1162-1751.6 prescriptions per 10,000 cases, p = 0.002). In primary care, acetylsalicylic acid was the most used antithrombotic, with higher use rates in prior than in naïve users. Post-discharge use occurred in 6686 (15.9%) subjects (median use = 10 days, IQR 9-30). Conclusions: Our study identified a consensus on prescribing antithrombotics in COVID-19 patients, but with low use rates in hospitals.

Lack of association between COVID-19 vaccines and miscarriage onset using a case-crossover design

Pregnant women might have an increased risk of SARS-COV-2 infection. Although evidence towards the efficacy and safety of COVID-19 is growing still there is room for improvement on the knowledge towards pregnancy adverse events, such as miscarriage. We explored the association of COVID-19 vaccine with the risk of miscarriages using the Real-World. We identified a cohort of vaccinated pregnancies using the BIFAP database which contains systematically recorded data on care patients in Spain (N = 4054). We then restricted it to those women who had a miscarriage using a validated algorithm (N = 607). Among them, we performed a case-crossover design to evaluate the effect of intermittent exposures on the risk of miscarriage. Adjusted Odds Ratio with their confidence intervals were calculated using two analytical approaches: conditional logistic regression and Generalized Linear Mixed-Effects Models. A total of 225 (37.1%) were aged 35-39 years. The most common comorbidities were asthma, migraine, gastritis, and hypothyroidism. A total of 14.7% received only one dose of COVID-19 and 85.3% two doses, respectively. A total of 36.8% of women with one dose and 27.6% with two doses received the vaccine 7 days prior to the miscarriage. Corresponding adjusted estimates for the risk of miscarriage using the conditional logistic regression where as follows: 1.65 (95% CI 0.85-3.23) when using as the sum of 3 control moments among women with one dose, 1.02 (95% CI 0.72-1.46) among women with two doses and 1.03 (95% CI 0.72, 1.46) using the whole study population. Very similar results were obtained when conducting the Generalized Linear Mixed-Effects Models. There was no overall increased risk of miscarriage onset associated with COVID-19 vaccine although contradictory results were found according to the number of doses. Further studies are required with larger sample sizes to assess this association.

[Use of antipsychotics in patients with dementia in Spain: Comparison with prescription of acetylcholinesterase inhibitors and memantine and analysis of associations]

OBJECTIVE

We have analyzed the prevalence of antipsychotics in patients with dementia in Spain, their age distribution and the influence of treatment with IACEs and memantine on their prescription.

METHOD

Descriptive, retrospective and cross-sectional study of the 2017 BIFAP database in over 65 years of age with dementia. Prescriptions of antipsychotics, IACEs and memantine were collected. For antipsychotics were also collected, the duration of treatment and time from dementia diagnosis to prescription.

RESULTS

A total of 1,327,792 subjects were retrieved, 89,464 (6.73%) with dementia. Antipsychotics were prescribed in 31.76%; by frequency: quetiapine (58.47%), risperidone (21%) and haloperidol (19.34%). Prescriptions of IACEs and memantine were clustered in those younger than 84 years and antipsychotics in those older than 85 (P<.001). Antipsychotics were maintained for a mean of 1174.5 days. In 26.4% of cases they were prescribed alone, OR 0.61 (95% CI: 0.59-0.62), in 35.85% associated with IACEs, OR 1.26 (95% CI: 1.22-1.30) and in 42.4% with memantine, OR 1.69 (95% CI: 1.62-1.78) (P<.000). From the diagnosis of dementia, 461 days (±1576.5) elapsed when isolated drugs were prescribed; 651 days (±1574.25) associated with IACEs and 1224 (±1779) with memantine.

CONCLUSIONS

One third of patients with dementia were prescribed antipsychotics, mostly atypical, more frequently in those older than 85 years and for prolonged periods. IACEs and memantine were associated with the risk of antipsychotic prescription, but paradoxically, with prolonged time to onset.

COVID-19 Distribution in Pregnancy, Drug Use Patterns and COVID-19 Medication during the Pandemic in Spain: Data from Real-World Electronic Health Records

Although pregnant women were considered a risk population for COVID-19, little is known of their drug use during the pandemic. We aimed to investigate COVID-19 distribution, drug use patterns and COVID-19 medication. We conducted a retrospective cohort of validated pregnancies aged 15-49 years, from January 2020 to December 2022, using the BIFAP database. An identified cohort of pregnant women with COVID-19 was matched by age, gestational age, length of pregnancy and outcome to a cohort free of COVID-19 (8413 vs. 24,975). We performed a descriptive analysis on COVID-19 cases, estimated the drug use patterns and assessed COVID-19-specific drugs within the week prior/after diagnosis, stratified by pandemic wave and gestational week. The results showed that 72% of pregnant women with COVID-19 received at least one prescription vs. 66.6% of those free of COVID-19, with analgesics, antibiotics and thyroid hormones being the most prescribed drugs in both groups. In the COVID-19 group, they were antithrombotics (40 prescriptions per 100 women), analgesic/NSAIDs (19.64/6.29) and antibiotics (6.95). COVID-19 cases gradually increased, peaking at the fifth and second waves. Prescription rates were similar when compared to pre-pandemic studies. The use of drugs compatible with COVID-19 treatments was in line with recommendations.

Development and Validation of Case-Finding Algorithms for Digestive Cancer in the Spanish Healthcare Database BIFAP

BACKGROUND

electronic health records (EHRs) are helpful tools in epidemiology despite not being primarily collected for research. In Spain, primary care physicians play a central role and manage patients even in specialized care. All of this introduces variability that may lead to diagnostic inconsistencies. Therefore, data validation studies are crucial, so we aimed to develop and validate case-finding algorithms for digestive cancer in the primary care database BIFAP.

METHODS

from 2001 to 2019, subjects aged 40-89 without a cancer history were included. Case-finding algorithms using diagnostic codes and text-mining were built. We randomly sampled, clustered, and manually reviewed 816 EHRs. Then, positive predictive values (PPVs) and 95% confidence intervals (95% CIs) for each cancer were computed. Age and sex standardized incidence rates (SIRs) were compared with those reported by the National Cancer Registry (REDECAN).

RESULTS

we identified 95,672 potential cases. After validation, the PPV (95% CI) for hepato-biliary cancer was 87.6% (81.8-93.4), for esophageal cancer, it was 96.2% (93.1-99.2), for pancreatic cancer, it was 89.4% (84.5-94.3), for gastric cancer, it was 92.5% (88.3-96.6), and for colorectal cancer, it was 95.2% (92.1-98.4). The SIRs were comparable to those reported by the REDECAN.

CONCLUSIONS

the case-finding algorithms demonstrated high performance, supporting BIFAP as a suitable source of information to conduct epidemiologic studies of digestive cancer.

Risk of ischemic stroke associated with direct oral anticoagulants discontinuation on patients with non-valvular atrial fibrillation

INTRODUCTION

Although direct oral anticoagulants' (DOACs) prescriptions have experienced immense growth in the last decade, the proportion of discontinuers is still common yielding an increased risk of ischemic stroke (IS) onset.

AIMS

We aimed to estimate the association between DOACs discontinuation and risk of IS among patients with non-valvular atrial fibrillation (NVAF).

METHODS

We used data from a cohort of new DOACs users, followed patients from the first DOAC prescription date up to IS (index date) and conducted a nested case-control analysis using conditional logistic regression. Adjusted odds ratios, 95% confidence intervals were calculated for discontinuation of DOACs (current use compared with past use). The latter, subdivided among those stopping treatment 3 to 2 months and 6 and 3 months prior to index date. The effect of naïve current users against IS onset compared with non-naïve current users was also evaluated.

RESULTS

DOACs discontinuation showed an OR of IS of 1.47 (95% CI: 1.02-2.12); estimates were 2.51 (95% CI: 1.84-3.42) for whom discontinued treatment within months 3 and 2 and 1.43 (95% CI: 0.96-2.13) for those between months 6 and 3 prior to index date. Analyzing DOACs individually, risk of IS associated with past users compared with current users: 1.98 (95% CI: 1.25-3.12) for apixaban, 1.38 (95% CI: 0.40-4.72) for edoxaban, 1.98 (95% CI: 1.24-2.65) for dabigatran and 1.87 (95% CI: 1.26-2.76) for rivaroxaban. Similar results were found when stratified by naïve and non-naïve users.

CONCLUSIONS

DOACs' discontinuation is associated with higher risk of IS, especially in the second and third months following interruption.

Effectiveness of homologous/heterologous booster COVID-19 vaccination schedules against severe illness in general population and clinical subgroups in three European countries

Using 4 data-sources (Spain, Italy, United Kingdom) data and a 1:1 matched cohort study, we aimed to estimate vaccine effectiveness (VE) in preventing SARS-CoV-2 infections with hospitalisations (±30 days) and death (±56 days) in general population and clinical subgroups with homologous/heterologous booster schedules (Comirnaty-BNT and Spikevax-MOD original COVID-19 vaccines) by comparison with unboosted individuals, during Delta and beginning of Omicron variants. Hazard Ratio (HR, by Cox models) and VE ([1-HR]*100) were calculated by inverse probability weights. Between December 2020-February 2022, in adults without prior SARS-CoV-2 infection, we matched 5.5 million people (>1 million with immunodeficiency, 343,727 with cancer) with a booster (3rd) dose by considering doses 1 and 2 vaccine brands and calendar time, age, sex, region, and comorbidities (immunodeficiency, cancer, severe renal disease, transplant recipient, Down Syndrome). We studied booster doses of BNT and MOD administered after doses 1 and 2 with BNT, MOD, or Oxford-AstraZeneca during a median follow-up between 9 and 16 weeks. BNT or MOD showed VE ranging from 70 to 86% across data sources as heterologous 3rd doses, whereas it was 42-88% as homologous 3rd doses. Depending on the severity and available follow-up, 3rd-dose effectiveness lasted between 1 and 5 months. In people with immunodeficiency and cancer, protection across data sources was detected with both heterologous (VE = 54-83%) and homologous (VE = 49-80%) 3rd doses. Overall, both heterologous and homologous 3rd doses with BTN or MOD showed additional protection against the severe effects of SARS-CoV-2 infections for the general population and for patients at potentially high risk of severe COVID-19 (elderly, people with immunodeficiency and cancer) in comparison with two doses schemes during Delta or early Omicron periods. The early VE after vaccination may be due to less testing among vaccinated pairs and unknown confounders, deserving cautious interpretation. The VE wane over time needs further in-depth research to properly envisage when or whether a booster of those vaccines should be administered.

Clinical pharmacology facing the real-world setting: Pharmacovigilance, pharmacoepidemiology and the economic evaluation of drugs

Traditionally, clinical pharmacology has focused its activities on drug-organism interaction, from an individual or collective perspective. Drug efficacy assessment by performing randomized clinical trials and analysis of drug use in clinical practice by carrying out drug utilization studies have also been other areas of interest. From now on, Clinical pharmacology should move from the analysis of the drug-individual interaction to the analysis of the drug-individual-society interaction. It should also analyze the clinical and economic consequences of the use of drugs in the conditions of normal clinical practice, beyond clinical trials. The current exponential technological development that facilitates the analysis of real-life data offers us a golden opportunity to move to all these other areas of interest. This review describes the role that clinical pharmacology has played at the beginning and during the evolution of pharmacovigilance, pharmacoepidemiology and economic drug evaluations in Spain. In addition, the challenges that clinical pharmacology is going to face in the following years in these three areas are going to be outlined too.

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.

Risk of Ischemic Stroke Associated with Calcium Supplements and Interaction with Oral Bisphosphonates: A Nested Case-Control Study

Conflicting results about the association of calcium supplements (CS) with ischemic stroke (IS) have been reported. We tested this hypothesis by differentiating between CS alone (CaM) and CS with vitamin D (CaD) and between cardioembolic and non-cardioembolic IS. We examined the potential interaction with oral bisphosphonates (oBs). A nested case-control study was carried out. We identified incident IS cases aged 40-90 and randomly sampled five controls per case matched by age, sex, and index date. Current users were compared to non-users. An adjusted odds ratios (AOR) and 95% CI were computed through conditional logistic regression. Only new users were considered. We included 13,267 cases (4400 cardioembolic, 8867 non-cardioembolic) and 61,378 controls (20,147 and 41,231, respectively). CaM use was associated with an increased risk of cardioembolic IS (AOR = 1.88; 95% CI: 1.21-2.90) in a duration-dependent manner, while it showed no association with non-cardioembolic IS (AOR = 1.05; 95% CI: 0.74-1.50); its combination with oBs increased the risk of cardioembolic IS considerably (AOR = 2.54; 95% CI: 1.28-5.04), showing no effect on non-cardioembolic. CaD use was not associated with either cardioembolic (AOR = 1.08; 95% CI: 0.88-1.31) or non-cardioembolic IS (AOR = 0.98; 95% CI: 0.84-1.13) but showed a small association with cardioembolic IS when combined with oBs (AOR = 1.35; 95% CI: 1.03-1.76). The results support the hypothesis that CS increases the risk of cardioembolic IS, primarily when used concomitantly with oBs.

Effect of the combination of diuretics, renin-angiotensin-aldosterone system inhibitors, and non-steroidal anti-inflammatory drugs or metamizole (triple whammy) on hospitalisation due to acute kidney injury: A nested case-control study

PURPOSE

Concomitant use of diuretics, renin-angiotensin-aldosterone system (RAAS) inhibitors, and non-steroidal anti-inflammatory drugs (NSAIDs) or metamizole, known as 'triple whammy' (TW), has been associated with an increased risk of acute kidney injury (AKI). Nevertheless, there is still uncertainty on its impact in hospitalisation and mortality. The aim of the study was to analyse the association between exposure to TW and the risk of hospitalisation for AKI, all-cause mortality and the need for renal replacement therapy (RRT).

METHODS

A case-control study nested in a cohort of adults exposed to at least one diuretic or RAAS inhibitor between 2009 and 2018 was carried out within the Pharmacoepidemiological Research Database for Public Health Systems (BIFAP). Patients hospitalised for AKI between 2010 and 2018 (cases) were matched with up to 10 patients of the same age, sex and region of Spain who had not been hospitalised for AKI as of the date of hospitalisation for AKI of the matching case (controls). The association between TW exposure versus non-exposure to TW and outcome variables was analysed using logistic regression models.

RESULTS

A total of 480 537 participants (44 756 cases and 435 781 controls) were included (mean age: 79 years). The risk of hospitalisation for AKI was significantly higher amongst those exposed to TW [adjusted odds ratio (aOR) 1.36, 95% confidence interval (95%CI) 1.32-1.40], being higher with current (aOR 1.60, 95%CI 1.52-1.69) and prolonged exposure (aOR 1.65, 95%CI 1.55-1.75). No significant association was found with the need of RRT. Unexpectedly, mortality was lower in those exposed to TW (aOR 0.81, 95%CI 0.71-0.93), which may be influenced by other causes.

CONCLUSION

Vigilance should be increased when diuretics, RAAS inhibitors, and NSAIDs or metamizole are used concomitantly, especially in patients at risk such as elderly patients.

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.

Association of oral bisphosphonates with cardioembolic ischemic stroke: a nested case-control study

Background: Bisphosphonates have been reported to increase the risk of atrial fibrillation. Therefore, it is conceivable that they may increase the risk of cardioembolic ischemic stroke (IS). However, most epidemiological studies carried out thus far have not shown an increased risk of IS, though none separated by the main pathophysiologic IS subtype (cardioembolic and non-cardioembolic) which may be crucial. In this study, we tested the hypothesis that the use of oral bisphosphonates increases specifically the risk of cardioembolic IS, and explored the effect of treatment duration, as well as the potential interaction between oral bisphosphonates and calcium supplements and anticoagulants. Methods: We performed a case-control study nested in a cohort of patients aged 40-99 years, using the Spanish primary healthcare database BIFAP, over the period 2002-2015. Incident cases of IS were identified and classified as cardioembolic or non-cardioembolic. Five controls per case were randomly selected, matched for age, sex, and index date (first recording of IS) using an incidence-density sampling. The association of IS (overall and by subtype) with the use of oral bisphosphonates within the last year before index date was assessed by computing the adjusted odds ratios (AOR) and their 95% CI using a conditional logistic regression. Only initiators of oral bisphosphonates were considered. Results: A total of 13,781 incident cases of IS and 65,909 controls were included. The mean age was 74.5 (SD ± 12.4) years and 51.6% were male. Among cases, 3.15% were current users of oral bisphosphonates, while among controls they were 2.62%, yielding an AOR of 1.15 (95% CI:1.01-1.30). Of all cases, 4,568 (33.1%) were classified as cardioembolic IS (matched with 21,697 controls) and 9,213 (66.9%) as non-cardioembolic IS (matched with 44,212 controls) yielding an AOR of 1.35 (95% CI:1.10-1.66) and 1.03 (95% CI: 0.88-1.21), respectively. The association with cardioembolic IS was clearly duration-dependent (AOR≤1 year = 1.10; 95% CI:0.82-1.49; AOR>1-3 years = 1.41; 95% CI:1.01-1.97; AOR>3 years = 1.81; 95% CI:1.25-2.62; p for trend = 0.001) and completely blunted by anticoagulants, even in long-term users (AOR>1 year = 0.59; 0.30-1.16). An interaction between oral bisphosphonates and calcium supplements was suggested. Conclusion: The use of oral bisphosphonates increases specifically the odds of cardioembolic IS, in a duration-dependent manner, while leaves materially unaffected the odds of non-cardioembolic IS.

Antihistamines as an early treatment for Covid-19

Infection with SARs-COV-2 results in COVID-19 disease. Between March 2020 and August 2021, 468 COVID-19 patients confirmed by PCR or antigen test, in Yepes, Spain, received early treatment with antihistamines, adding azithromycin in selected cases. The primary endpoint is the hospitalization rate of COVID-19 patients, and the secondary endpoints are ICU admission and mortality rates. All endpoints are compared with the official Spanish rates during the time period of the study. There were 20 hospital admissions (hospitalization rate 4,3%), 5 ICU admissions (ICU admission rate 1,1%) and 3 deaths (fatality rate of 0,6%). No patients in the study required follow up treatment, which suggest they did not develop long COVID. Results from this retrospective trail indicate that early treatment of SARS-COV-2 positive patients with antihistamines may reduce the odds of hospitalization (OR: 0.490, CI: 0.313-0.767, p-value: 0.001). Randomized controlled clinical trials are needed to further evaluate the effects of early antihistamine treatment of SARS-CoV-2 patients to prevent hospitalization, ICU admission, mortality and long-covid.

Flecainide and risk of skin neoplasms: Results of a large nested case-control study in Spain and Denmark

Background: A previous study in Denmark suggested an increased melanoma risk associated with the use of flecainide. Objective: To study the association between flecainide use and the risk of melanoma and non-melanoma skin cancer in Spain and Denmark. Methods: We conducted a multi-database case-control study in (database/study period) Spain (SIDIAP/2005-2017 and BIFAP/2007-2017) and Denmark (Danish registries/2001-2018). We included incident cases of melanoma or non-melanoma skin cancer (NMSC) aged ≥18 with ≥2 years of previous data (≥10 years for Denmark) before the skin cancer and matched them to controls (10:1 by age and sex). We excluded persons with immunosuppression or previous cancer. We defined ever-use as any prescription fill and high-use as a cumulative dose of at least 200 g (reference: never-use). We categorized a cumulative dose for a dose-response assessment. We used conditional logistic regression to compute ORs (95% CI) adjusted for photosensitizing, anti-neoplastic, disease-specific drugs and comorbidities. Results: The total numbers of melanoma/NMSC cases included were 7,809/64,230 in SIDIAP, 4,661/31,063 in BIFAP, and 27,978/152,821 in Denmark. In Denmark, high-use of flecainide was associated with increased adjusted ORs of skin cancer compared with never-use [melanoma: OR 1.97 (1.38-2.81); NMSC: OR 1.34 (1.15-1.56)]. In Spain, an association between high-use of flecainide and NMSC was also observed [BIFAP: OR 1.42 (1.04-1.93); SIDIAP: OR 1.19 (0.95-1.48)]. There was a non-significant dose-response pattern for melanoma in Denmark and no apparent dose-response pattern for NMSC in any of the three databases. We found similar results for ever-use of flecainide. Conclusion: Flecainide use was associated with an increased risk of melanoma (Denmark only) and NMSC (Denmark and Spain) but without substantial evidence of dose-response patterns. Further studies are needed to assess for possible unmeasured confounders.

The Risk of SARS-CoV-2 Infection in Pregnant Women: An Observational Cohort Study Using the BIFAP Database

BACKGROUND

It has been suggested that women experiencing during pregnancy several physiological and immunological changes that might increase the risk of any infection including the SARS-CoV-2.

OBJECTIVE

We aimed to quantify the risk of SARS-CoV-2 infection during pregnancy compared with women with no pregnancies.

METHODS

We used data from the BIFAP database and a published algorithm to identify all pregnancies during 2020. Pregnancies were matched (1:4) by age region, and length of pregnancy with a cohort of women of childbearing age. All women with SARS-CoV-2 infection before entering the study were discarded. We estimated incidence rates of SARS-CoV-2 with 95% confidence intervals (CIs) expressed by 1000 person-months as well as Kaplan-Meier figures overall and also stratified according to pregnancy period: during pregnancy, at puerperium (from end of pregnancy up to 42 days) and after pregnancy. (from 43 days after pregnancy up to end pf study period (i.e., June 2021). We conducted a Cox regression to assess risk factors for SARS-COV infection. The incidence rate of SARS-CoV-2 infection expressed by 1000 person-months were.

RESULTS

There was a total of 103,185 pregnancies and 412,740 matched women at childbearing, with a mean age of 32.3 years. The corresponding incidence rates of SARS-CoV-2 infection according to cohorts were: 2.44 cases per 1000 person-months (confidence interval (CI) 95%: 2.40-2.50) and 4.29 (95% CI: 4.15-4.43) for comparison cohort. The incidence rate ratio (IRR) of SARS-CoV-2 was 1.76 (95% CI: 1.69-1.83). When analyzing according to pregnancy period, the IRRs were 1.30 (95% CI: 11.20-1.41) during the puerperium and 1.19 (95% CI: 41.15-1.23) after pregnancy. In addition to pregnancy itself, other important risk factors were obesity (1.33 (95% CI: 1.23-1.44)) and diabetes (1.23 (95% CI: 11.00-1.50).

CONCLUSION

Pregnant women are at increased risk of SARS-CoV-2 infection compared with women of childbearing age not pregnant. Nevertheless, there is a trend towards reverting during puerperium and after pregnancy.

Myocarditis and pericarditis associated with SARS-CoV-2 vaccines: A population-based descriptive cohort and a nested self-controlled risk interval study using electronic health care data from four European countries

Background: Estimates of the association between COVID-19 vaccines and myo-/pericarditis risk vary widely across studies due to scarcity of events, especially in age- and sex-stratified analyses. Methods: Population-based cohort study with nested self-controlled risk interval (SCRI) using healthcare data from five European databases. Individuals were followed from 01/01/2020 until end of data availability (31/12/2021 latest). Outcome was first myo-/pericarditis diagnosis. Exposures were first and second dose of Pfizer, AstraZeneca, Moderna, and Janssen COVID-19 vaccines. Baseline incidence rates (IRs), and vaccine- and dose-specific IRs and rate differences were calculated from the cohort The SCRI calculated calendar time-adjusted IR ratios (IRR), using a 60-day pre-vaccination control period and dose-specific 28-day risk windows. IRRs were pooled using random effects meta-analysis. Findings: Over 35 million individuals (49·2% women, median age 39-49 years) were included, of which 57·4% received at least one COVID-19 vaccine dose. Baseline incidence of myocarditis was low. Myocarditis IRRs were elevated after vaccination in those aged < 30 years, after both Pfizer vaccine doses (IRR = 3·3, 95%CI 1·2-9.4; 7·8, 95%CI 2·6-23·5, respectively) and Moderna vaccine dose 2 (IRR = 6·1, 95%CI 1·1-33·5). An effect of AstraZeneca vaccine dose 2 could not be excluded (IRR = 2·42, 95%CI 0·96-6·07). Pericarditis was not associated with vaccination. Interpretation: mRNA-based COVID-19 vaccines and potentially AstraZeneca are associated with increased myocarditis risk in younger individuals, although absolute incidence remains low. More data on children (≤ 11 years) are needed.

Influenza Vaccination and Risk of Ischemic Stroke: A Population-Based Case-Control Study

BACKGROUND AND OBJECTIVES

To assess the relationship between influenza vaccination in the general population and risk of a first ischemic stroke (IS) during pre-epidemic, epidemic, and postepidemic periods.

METHODS

A nested case-control study was conducted in a Spanish primary care database over 2001-2015. Individuals aged 40-99 years with at least 1 year registry and no history of stroke or cancer were selected to conform the source cohort, from which incident IS cases were identified and classified as cardioembolic or noncardioembolic. Five controls per case were randomly selected, individually matched with cases for exact age, sex, and date of stroke diagnosis (index date). A patient was considered vaccinated when he/she had a recorded influenza vaccination at least 14 days before the index date within the same season. Adjusted odds ratios (aORs) and their respective 95% CIs were computed through a conditional logistic regression. Pneumococcal vaccination was used as a negative control.

RESULTS

From a cohort of 3,757,621 patients, we selected 14,322 incident IS cases (9,542 noncardioembolic and 4,780 cardioembolic) and 71,610 matched controls. Of them, 41.4% and 40.5%, respectively, were vaccinated yielding a crude OR of 1.05 (95% CI 1.01-1.10). Vaccinated patients presented a higher prevalence of vascular risk factors, diseases, and comedication than those nonvaccinated, and after full adjustment, the association of influenza vaccination with IS yielded an aOR of 0.88 (95% CI 0.84-0.92), appearing early (aOR15-30 days 0.79; 95% CI 0.69-0.92) and slightly declining over time (aOR>150 days 0.92; 95% CI 0.87-0.98). A reduced risk of similar magnitude was observed with both types of IS, in the 3 epidemic periods, and in all subgroups analyzed (men, women, individuals younger and older than 65 years of age, and those with intermediate and high vascular risk). By contrast, pneumococcal vaccination was not associated with a reduced risk of IS (aOR 1.08; 95% CI 1.04-1.13).

DISCUSSION

Results are compatible with a moderate protective effect of influenza vaccine on IS appearing early after vaccination. The finding that a reduced risk was also observed in pre-epidemic periods suggests that either the "protection" is not totally linked to prevention of influenza infection or it may be partly explained by unmeasured confounding factors.

Antidepressant use and off-label prescribing in primary care in Spain (2013-2018)

INTRODUCTION

Recent studies show an increase in the use of antidepressants in minors (younger than 18 years), although few antidepressants are indicated for this age group. The aim of our study was to calculate the annual prevalence of antidepressant use in children and adolescents and to review the adherence of prescription to current indications.

METHODS

Study of the prevalence of antidepressant use in minors based on the records of the Electronic Database for Pharmacoepidemiologic Studies in Primary Care (BIFAP) of Spain for the 2013-2018 period, considering at least one prescription per year for each patient.

RESULTS

The prevalence of antidepressant prescription in patients from the BIFAP cohort increased between 2013 (7.97 prescriptions per 1000 patients) and 2018 (8.87 prescriptions per 1000 patients), in most groups and in both sexes. In this period, female patients received the most prescriptions, surpassing prescriptions in male patients by up to 2.5 points in the overall rates. In patients younger than 13 years, this trend was inverted and antidepressant use was higher in male patients. The prevalence of prescription rose with increasing patient age, as did the proportion of off-label prescriptions. The use of off-label medication decreased over time.

CONCLUSIONS

There was a gradual increase in the prevalence of antidepressant prescription in minors younger than 18 years, with a predominance of the female sex. The high proportion of unapproved medication use in this age group calls for more thorough investigation of the risk-benefit balance of these treatments and of safer treatment alternatives.

Development and external validation of a 1- and 5-year fracture prediction tool based on electronic medical records data: The EPIC risk algorithm

OBJECTIVES

We aimed to develop and validate a fracture risk algorithm for the automatic identification of subjects at high risk of imminent and long-term fracture risk.

RESEARCH, DESIGN, AND METHODS

A cohort of subjects aged 50-85, between 2007 and 2017, was extracted from the Catalan information system for the development of research in primary care database (SIDIAP). Participants were followed until the earliest of death, transfer out, fracture, or 12/31/2017. Potential risk factors were obtained based on the existing literature. Cox regression was used to model 1 and 5-year risk of hip and major fracture. The original cohort was randomly split in 80:20 for development and internal validation purposes respectively. External validation was explored in a cohort extracted from the Spanish database for pharmaco-epidemiological research in primary care.

RESULTS

A total of 1.76 million people were included from SIDIAP (50.7 % women with mean age of 65.4 years). Hip and major fracture incidence rates were 3.57 [95%CI 3.53 to 3.60] and 11.61 [95%CI 11.54 to 11.68] per 1000 person-years, respectively. The derived model included 19 risk factors. Internal validity showed good results on calibration and discrimination. The 1-year C-statistic for hip and major fracture were 0.851 (95%CI 0.853 to 0.864), and 0.717 (95%CI 0.742 to 0.749) respectively. The 5-year C-statistic for hip and major fracture were 0.849 (95%CI 0.847 to 0.852) and 0.724 (95%CI 0.721 to 0.727) respectively. External validation showed good performance for hip and major fracture risk prediction.

CONCLUSIONS

We have developed and validated a clinical prediction tool for 1- and 5-year hip and major osteoporotic fracture risks using electronic primary care data. The proposed algorithm can be automatically estimated at the population level using the available primary care records. Future work is needed on the cost-effectiveness of its use for population-based screening and targeted prevention of osteoporotic fractures.

Prescribing Patterns of Codeine and Alternative Medicines in Children in Europe

Introduction

Concerns over serious respiratory depression in children led to two European Union (EU) referral procedures (in 2013 and 2015) to review the benefit–risk balance of codeine in this population when used for pain relief, cough or cold. Consequently, codeine should no longer be used in children aged < 12 years and restrictions were introduced for treatment in children ≥ 12 years.

Objective

This multinational collaborative study aimed to assess the effectiveness of these risk minimisation measures by evaluating changes in prescribing of codeine and alternative treatments.

Method

Children under 12 and 12–18 years old were followed between 2010 and 2017 to analyse quarterly trends in prescribing of codeine and alternative treatments in electronic health records from France, Germany, Norway, Spain and the United Kingdom using interrupted time series analysis.

Results

Overall prescribing of codeine in children decreased in all five countries, reaching near zero prevalence in children under 12 years of age. This was accompanied by an increase in use of other opioid analgesics in France (from 0.15 to 0.56 prevalence per 100 person-years immediately after the first referral), Norway (from 0.0006 to 0.0013 at the end of the study), the United Kingdom (from 0.018 to 0.05 at the end of the study), and an increase in non-opioid analgesics in Norway (from 0.045 to 0.075 at the end of the study) after the referral on pain relief indication. The referral on cough/cold indication led to a decrease in use of opioid and non-opioid antitussives in children aged < 12 years in France (from 10 to 7 and 20 to 16, respectively) and had no impact in other countries. Overall prescribing trends for codeine and alternatives were similar across both age groups within each country.

Conclusion

The decrease in use of codeine shows that healthcare professionals followed the adopted measures and switched prescribing practices for pain management in children aged < 18 years towards opioid or non-opioid analgesics depending on national clinical and reimbursement settings. Whist the magnitude of the first referral on pain differed between countries, the second referral on cough/cold had only a minimal impact on the use of codeine and antitussives.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40264-022-01214-y.

Assessment of thyroiditis risk associated with HPV vaccination among girls aged 9-18 years: A time-varying cohort study

BACKGROUND

Previous studies have suggested a relationship between human papillomavirus vaccine and autoimmune diseases, including thyroiditis. Thus, we aimed to evaluate the risk of thyroiditis associated with HPV vaccination among girls using the Primary Care Database For Pharmacoepidemiological Research (BIFAP) in Spain.

METHODS

In this retrospective cohort study, girls in BIFAP aged 9-18 years from 2007 to 2016, free of past thyroiditis and HPV vaccination, were included. Hazard Ratios (HRs; 95% CI) of thyroiditis were calculated within exposed periods (up to 2 years of vaccination) and post-exposed periods (from 2 years after vaccination onwards) compared with non-exposed periods, overall, by dose and by type of vaccine, adjusted for potential confounders collected at different times. In a post-hoc analysis, we moved back the thyroiditis date (30 days) as a theoretical delay in diagnosis.

RESULTS

Out of the 388,411 girls included in the cohort, 153,924 were vaccinated against HPV and 480 thyroiditis (253 autoimmune) cases were identified (334 non-exposed; 103 exposed; 43 post-exposed). Adjusted HR was 1.18 [95% CI: 0.79-1.76] for exposed (1.25 [0.77-2.04] for bi- and 1.15 [0.76-1.76] for quadri-valent vaccines) and 1.26 [0.74-2.14] for post-exposed periods. HR was 1.50 [0.87-2.59] for the 1^st dose, 1.13 [0.66-1.91] for the 2^nd and 1.11 [0.71-1.72] for the 3^rd one. When the diagnosis date was moved back, the risk was 1.14 [0.76-1.70] for exposed period, being 1.80 [0.86-3.76] and 1.40 [0.74-2.66] after 1^st dose of bi- and quadri-valent, respectively.

CONCLUSIONS

We did not observe an increased risk of thyroiditis following HPV vaccination (whether bi- or quadri-valent). Even though the point estimate was higher after 1^st HPV vaccination dose than after subsequent doses, a dose-effect was not confirmed. Results remained similar after applying a lag time.

The role of prenatal exposure to antidepressants, anxiolytic, and hypnotics and its underlying illness on the risk of miscarriage using BIFAP database

Purpose

Despite the notable increase on the prescription of antidepressants and anxiolytics during pregnancy, recommendation on maintaining the treatment during prenatal period is still controversial. We aimed to separately assess the role of effects of the antidepressants and anxiolytic and the underlying illness, controlled by potential confounding associated with miscarriage onset.

Methods

We used data from a validated pregnant cohort aged 15–49 years from 2002 to 2016 using BIFAP database. All confirmed miscarriages were used to perform a nested control analysis using conditional logistic regression. Women were classified according to use of each drug of interest into four mutually exclusive groups: nonusers, users only during prepregnancy, continuers, and initiators during first trimester. Adjusted odds ratios (aORs) for major confounders during pregnancy such as number of visits to primary care practitioners visits, obesity, smoking, HTA, diabetes with 95% confidence intervals were calculated.

Results

Compared with nonusers, antidepressants continuers had the highest increased risk of miscarriage aOR (95%) of 1.29 (1.13–1.46), being continuers of paroxetine and fluoxetine the antidepressants with the strongest association. Likewise, continuers of anxiolytics and initiators showed an increased risk of 1.19 (1.04–1.37) and 1.30 (1.13–1.50). When separating the effect between the condition itself or the treatment, women exposed during first trimester, regardless treatment duration and/or the underlying illness, had the highest risk 1.27 (1.08–1.51) for antidepressants and 1.25 (1.13–1.39) for anxiolytics.

Conclusions

Our analysis showed an association between prenatal exposure to antidepressants and anxiolytics and miscarriage onset after controlling by potential confounding adjusting for confounders and the underlying illness. This association was not supported for hypnotic medications. Further studies are warranted to evaluate the risk of miscarriage among subpopulation of pregnant women requiring these medications.

Statins and Colorectal Cancer Risk: A Population-Based Case-Control Study and Synthesis of the Epidemiological Evidence

(1) Background: The pleiotropic effects of statins may explain a chemoprotective action against colorectal cancer (CRC). Many studies have tested this hypothesis, but results have been inconsistent so far. Moreover, few have examined statins individually which is important for determining whether there is a class effect and if lipophilicity and intensity may play a role. (2) Methods: From 2001–2014, we carried out a study comprised of 15,491 incident CRC cases and 60,000 matched controls extracted from the primary healthcare database BIFAP. We fit a logistic regression model to compute the adjusted-odds ratios (AOR) with their 95% confidence intervals (CIs). Additionally, we carried out a systematic review and meta-analysis. (3) Results: Current use of statins showed a reduced risk of CRC (AOR = 0.87; 95% CI: 0.83–0.91) not sustained after discontinuation. The association was time-dependent, starting early (AOR_{6months–1year} = 0.85; 95% CI: 0.76–0.96) but weakened beyond 3-years. A class effect was suggested, although only significant for simvastatin and rosuvastatin. The risk reduction was more marked among individuals aged 70 or younger, and among moderate-high intensity users. Forty-eight studies were included in the meta-analysis (pooled-effect-size = 0.90; 95% CI: 0.86–0.93). (4) Conclusions: Results from the case-control study and the pooled evidence support a moderate chemoprotective effect of statins on CRC risk, modified by duration, intensity, and age.

Selective Serotonin Reuptake Inhibitors and Risk of Noncardioembolic Ischemic Stroke: A Nested Case-Control Study

BACKGROUND

Multiple studies have reported that the use of selective serotonin reuptake inhibitors (SSRIs) is associated with an increased risk of ischemic stroke; however, this finding may be the result of a confounding by indication. We examined the association using different approaches to minimize such potential bias.

METHODS

A nested case-control study was carried out in a Spanish primary health-care database over the study period 2001 to 2015. Cases were patients sustaining an ischemic stroke with no sign of cardioembolic or unusual cause. For each case, up to 5 matched controls (for exact age, sex, and index date) were randomly selected. Antidepressants were divided in 6 pharmacological subgroups according to their mechanism of action. The current use of SSRIs (use within a 30-day window before index date) was compared with nonuse, past use (beyond 365 days) and current use of other antidepressants through a conditional logistic regression model to obtain adjusted odds ratios and 95% CI. Only initiators of SSRIs and other antidepressants were considered.

RESULTS

A total of 8296 cases and 37 272 matched controls were included. Of them, 255 (3.07%) were current users of SSRIs among cases and 834 (2.24%) among controls, yielding an adjusted odds ratio of 1.14 (95% CI, 0.97-1.34) as compared with nonusers, 0.94 (95% CI, 0.77-1.13) as compared with past-users and 0.74 (95% CI, 0.58-0.93) as compared with current users of other antidepressants. No relevant differences were found by duration (≤1, >1 year), sex, age (<70, ≥70 years old) and background vascular risk.

CONCLUSIONS

The use of SSRIs was not associated with an increased risk of noncardioembolic ischemic stroke. On the contrary, as compared with other antidepressants, SSRIs appeared to be protective.

Effect of regulatory interventions on agomelatine use in Spain: A multiple intervention time-series analysis in a nationwide electronic healthcare record database

BACKGROUND

Liver injury is an important identified risk for agomelatine and several measures were put in place to prevent and minimize such risk. The study aims to assess the impact of four interventions on the incidence of agomelatine use, particularly among patients aged ≥75 in Spain between 2011 and 2018.

METHODS

Quasi-experimental interrupted time-series analysis to examine data from a nationwide electronic healthcare record database (BIFAP). Quarterly cumulative incidence of agomelatine use per 100 000 patients was calculated and the impact of four regulatory interventions was quantified.

RESULTS

The incidence of agomelatine use decreased by 85% and 87% from first quarter 2011 to last quarter 2018 in patients below and above 75 years old, respectively. Regulatory actions taken were not associated with an immediate and significant falling level of use or slope. The incidence was less than expected 6 months after the first and third intervention for patients below and above 75 years old, and more than expected after the second and fourth intervention for both populations, though these analyses were underpowered to observe significant results. The downward trend became less pronounced, reaching a residual level of use, which remained stable in the last segment of the study period.

CONCLUSION

New users of agomelatine decreased throughout the study period, starting before interventions took place. The effect of specific interventions might be masked by the progressive decrease tendency, constant over the study period. The effects of external factors that might overlap, unintended consequences, and issues concerning statistical modeling in situations where rates are already falling, should be considered when interpreting the results.

Influenza vaccine and risk of acute myocardial infarction in a population-based case-control study

OBJECTIVE

To assess the relationship between influenza vaccination and risk of a first acute myocardial infarction (AMI) in the general population by different epidemic periods.

METHODS

This is a population-based case-control study carried out in BIFAP (Base de datos para la investigación farmacoepidemiológica en atención primaria), over 2001-2015, in patients aged 40-99 years. Per each incident AMI case, five controls were randomly selected, individually matched for exact age, sex and index date (AMI diagnosis). A patient was considered vaccinated when he/she had a recorded influenza vaccination at least 14 days before the index date within the same season. The association between influenza vaccination and AMI risk was assessed through a conditional logistic regression, computing adjusted ORs (AOR) and their respective 95% CIs. The analysis was performed overall and by each of the three time epidemic periods per study year (pre-epidemic, epidemic and postepidemic).

RESULTS

We identified 24 155 AMI cases and 120 775 matched controls. Of them, 31.4% and 31.2%, respectively, were vaccinated, yielding an AOR of 0.85 (95% CI 0.82 to 0.88). No effect modification by sex, age and background cardiovascular risk was observed. The reduced risk of AMI was observed shortly after vaccination and persisted over time. Similar results were obtained during the pre-epidemic (AOR=0.87; 95% CI 0.79 to 0.95), epidemic (AOR=0.89; 95% CI 0.82 to 0.96) and postepidemic (AOR=0.83; 95% CI 0.79 to 0.87) periods. No association was found with pneumococcal vaccine (AOR=1.10; 95% CI 1.06 to 1.15).

CONCLUSIONS

Results are compatible with a moderate protective effect of influenza vaccine on AMI in the general population, mostly in primary prevention, although bias due to unmeasured confounders may partly account for the results.

A strategy for assessment and validation of major bleeding cases in a primary health care database in Spain

PURPOSE

This study aims to validate major bleeding (MB) cases within a cohort of new users of direct oral anticoagulants (DOACs) in Electronic health records (EHRs) from primary care in Spain (BIFAP), introducing more efficient techniques and automating the process of validation in the pharmacoepidemiologic research with EHR data as much as possible.

METHODS

Registered bleedings were identified in a cohort of new users of DOACs in BIFAP using ICPC 2 and ICD 9 codes; we ascertained these bleedings as MB through a validation strategy based on the MB definition from the International Society on Thrombosis and Hemostasis, which used hospitalization and critical localization as proxies. We assessed hospitalization with hospital discharge information (only available for some years and regions) and a free text-based algorithm created to identify hospitalization in EHR's clinical notes. Incidence rates (IR) of MB were evaluated by bleeding type.

RESULTS

The study cohort included 104 614 patients, with 274521.5 p-y of follow up. There were 6143 registered bleedings during the study period (519 intracranial bleeding - ICB, 4606 gastrointestinal bleeding - GIB, 1018 extracranial bleeding - ECB), from which 1679 were confirmed as MB (416 ICB, 1086 GIB, and 177 ECB). The free text-based semi-automatic algorithm had moderate recall (0.59), but high specificity (0.99), and precision (0.94).

CONCLUSION

The combination of hospitalization and critical localization is a valid approach to validate MB in EHRs with incomplete information. The use of more automatic methods for case validation instead of manual review of clinical notes is favored.

The prevalence and incidence rate of overweight and obesity among 2.5 million children and adolescents in Spain

INTRODUCTION AND OBJECTIVES

Childhood obesity trends are plateauing in Spain, but limited information is available about how they differ by region. This study assessed childhood and adolescent the prevalence and incidence of overweight and obesity from 2005 to 2017 across 8 Spanish regions.

METHODS

This longitudinal study used height and weight measurements from 2.5 million children aged 2 to 17 years to calculate overweight and obesity, according to the World Health Organization (WHO) guidelines. Data were obtained from The Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria, and the Information System for Research in Primary Care. Prevalence and incidence rates and trends from 2005 to 2017 were calculated and stratified by age, sex, and region.

RESULTS

The overall obesity prevalence increased in boys and girls from age 2 (0.8%; 95%CI, 0.8-0.9 in both sexes) until peaking at age 7 in girls (17.3%; 95%CI, 17.1-17.5) and age 9 in boys (24.1%; 95%CI 23.9-24.3). The highest and lowest obesity prevalences were observed in Murcia and Navarre. Overall obesity prevalence trends decreased from 2005 to 2017 in all age-sex groups and in most regions. Highest obesity incidence rates were found in children aged 6 to 7 years, (4.5 [4.5-4.5] and 3.5 [3.5-3.5] new obesity cases per 100 person-years in boys and girls, respectively). Boys had higher prevalence and incidence rates than girls across all regions. Overweight/obesity prevalence and incidence rates and their trends were consistently higher than the obesity results, although a similar pattern was observed across sex and age.

CONCLUSIONS

Overweight and obesity prevalence slightly decreased in Spain from 2005 to 2017, but regional, sex, and age differences persisted. Because incidence peaked around the age of 6 years, it may be important to begin health promotion programs at an early age.

Risk of acute myocardial infarction among new users of chondroitin sulfate: A nested case-control study

Objective

To test the hypothesis that the use of chondroitin sulfate (CS) or glucosamine reduces the risk of acute myocardial infarction (AMI).

Design

Case-control study nested in a primary cohort of patients aged 40 to 99 years, using the database BIFAP during the 2002–2015 study period. From this cohort, we identified incident cases of AMI and randomly selected five controls per case, matched by exact age, gender, and index date. Adjusted odds ratios (AOR) and 95% confidence interval (CI) were computed through a conditional logistic regression. Only new users of CS or glucosamine were considered.

Results

A total of 23,585 incident cases of AMI and 117,405 controls were included. Of them, 89 cases (0.38%) and 757 controls (0.64%) were current users of CS at index date, yielding an AOR of 0.57 (95%CI: 0.46–0.72). The reduced risk among current users was observed in both short-term (<365 days, AOR = 0.58; 95%CI: 0.45–0.75) and long-term users (>364 days AOR = 0.56; 95%CI:0.36–0.87), in both sexes (men, AOR = 0.52; 95%CI:0.38–0.70; women, AOR = 0.65; 95%CI:0.46–0.91), in individuals over or under 70 years of age (AOR = 0.54; 95%CI:0.38–0.77, and AOR = 0.61; 95%CI:0.45–0.82, respectively) and in individuals at intermediate (AOR = 0.65; 95%CI:0.48–0.91) and high cardiovascular risk (AOR = 0.48; 95%CI:0.27–0.83), but not in those at low risk (AOR = 1.11; 95%CI:0.48–2.56). In contrast, the current use of glucosamine was not associated with either increased or decreased risk of AMI (AOR = 0.86; 95%CI:0.66–1.08).

Conclusions

Our results support a cardioprotective effect of CS, while glucosamine seems to be neutral. The protection was remarkable among subgroups at high cardiovascular risk.

Papillomavirus vaccination and Guillain-Barre Syndrome among girls: A cohort study in Spain

BACKGROUND

Studies of the association of Guillain-Barré Syndrome (GBS) with papillomavirus vaccination (HPVv; scheduled from 2007) have provided contradicting results, probably due to the low frequency of this disease. We aimed at estimating that risk relative to non-vaccination among girls, by using the Spanish Primary Care Database for Pharmacoepidemiological Research (BIFAP).

METHODS

A cohort study of girls aged 9-18 years during 2007-2016 free of GBS or HPVv was selected and followed up to GBS diagnosis. Follow-up time was divided by time-varying HPVv exposure and confounders. Crude Incidence rates (IR per 1,000,000 person-years (py)) and adjusted Hazard Ratios (HR) of GBS were estimated anytime after vaccination compared to non-exposed periods. HRs were also estimated for the first 90 days after HPVv (risk-window) and thereafter.

RESULTS

Out of 388,849 girls, of which 154,255 were vaccinated, 6 'confirmed' GBS cases occurred during non-exposure periods (IR of 5.83 per million person-years; 95% CI: 2.62-12.97) and 3 'confirmed' cases anytime after vaccination (IR of 7.87; 95% CI: 2.54-24.39). The resulting adjusted HR anytime after vaccination was 1.24 (95% CI: 0.19-8.00). All three cases occurred after the risk window of 90 days with an HR of 1.77 (95% CI: 0.25-12.54) for post-exposure periods as compared with non-exposure. Since zero cases occurred during the risk window, no HR could be estimated for exposed periods.

CONCLUSIONS

Incidences of GBS were in line with the range previously reported for young people, supporting the potential of BIFAP for performing studies on GBS. However, a lack of power may be present for quantifying the relative risk of such a rare disease after the vaccination among the study cohort, where we can only exclude an increased risk of 8-times relative to no vaccination.

Use of hydrochlorothiazide and risk of skin cancer in a large nested case-control study in Spain

PURPOSE

Hydrochlorothiazide (HCTZ) use has been linked to skin cancer in northern European countries. We assessed the association between HCTZ exposure and risk of malignant melanoma (MM) and keratinocyte carcinoma (KC) in a European Mediterranean population.

METHODS

Two parallel nested case-control studies were conducted in Spain using two electronic primary healthcare databases, each one providing data on both exposure and outcomes: SIDIAP and BIFAP. Cancer cases were matched to 10 controls by age and gender through risk-set sampling. The ORs and 95% CI for MM and KC associated with previous HCTZ use were estimated using conditional logistic regression. In BIFAP, KC cases were further identified as basal cell carcinoma (BCC) or squamous cell carcinoma (SCC).

RESULTS

In adjusted analyses, both ever and cumulative high (≥50,000 mg) use of HCTZ were associated with an increased risk of KC. The risk estimates for high use were 1.30 (1.26-1.34) in SIDIAP and 1.20 (1.12-1.30) in BIFAP, with a lower risk for BCC (1.11 [1.02-1.21]) than for SCC (1.71 [1.45-2.02]). A dose-response relationship was observed between cumulative doses of HCTZ and KC risk. Inconsistent results were found for high use of HCTZ and risk of MM: 1.25 (1.09-1.43) in SIDIAP and 0.85 (0.64-1.13) in BIFAP.

CONCLUSIONS

In this European Mediterranean population, a high cumulative use of HCTZ was related to an increased risk of KC with a clear dose-response pattern.

An Estimation of the Incidence of Thyroiditis Among Girls in Primary Care in Spain

OBJECTIVE

As for other auto-immune processes, thyroiditis is monitored after vaccinations. The aim was to estimate the baseline incidence of thyroiditis among girls, before investigating papillomavirus vaccination as a potential risk factor.

METHODS

Observational cohort study including girls aged 9-18 years and registered between 2002-2016 in the Spanish Primary Care Database for Pharmacoepidemiological Research. Girls were followed until a thyroiditis occurred, 19 years of age, left the cohort, died, or the study ended. Anonymized records were reviewed for diagnosis confirmation (endocrine discharge letter and/or free-text comments) in a random sample. Incidence rate (IR) per 10⁵ person years (/10⁵ py) was estimated.

RESULTS

The cohort numbered 480,169 girls, of whom 641 had a record of thyroiditis: 346 autoimmune thyroiditis; 17 thyroiditis of other types; and 278 unspecified. Incidence of recorded thyroiditis increased with age, from 23.96 at age 9 years to 47.91 at age 14 years, and stabilized around 31.06-34.43 among girls aged 15-18 years. Of the 98 records reviewed, 60.2% were ‘confirmed’ cases, 32.7% ‘possible’ and 7.1% were discarded. After correction for discarded cases, IR=20.83 ‘confirmed’ cases, increasing to 32.12/10⁵ py when ‘confirmed’ plus ‘possible’ cases were included. Between 2002-2005, incidences were lower (16.28 and 20.93 cases/10⁵ py) than in the period 2007-2016 (21.17 and 33.78 cases/10⁵ py) for ‘confirmed’ and ‘confirmed’ plus ‘possible’, respectively.

CONCLUSION

Two-thirds of the recorded thyroiditis included confirmatory evidence. The incidence of thyroiditis among girls increased with age and in the later period, and remained stable among girls aged 15-18 years.

A Validation Study on the Frequency and Natural History of Miscarriages Using the Spanish Primary Care Database BIFAP

(1) Background: There is a major gap of knowledge towards the natural history of miscarriages in electronic medical records. We aimed to calculate the frequency of miscarriages using data from BIFAP database. (2) Methods: We identified all pregnancy losses and carried out a multistep validation exercise. Potential cases with positive predictive values (PPV) of miscarriage confirmation <85% or those confirming other pregnancy loss were excluded. Kaplan–Meier figures and incidence rates (IRs) of miscarriage with 95% confidence intervals (CIs) expressed by 1000 person-weeks were calculated. Stratifying analysis by age, specific high-risk groups, and drug exposure within the pre-pregnancy period were performed restricted to women with recording last menstrual period (LMP). (3) Results: Women with confirmed miscarriage (N = 18,070), tended to be older, with higher frequency of comorbidities and drug utilization. Restricting to women with LPM recorded, IR of miscarriage was 10.89 (CI 95% 10.68–11.10) per 1000 women-weeks, with a median follow-up of 10 weeks (IQR: 8–12). The IR according to age was: 2.71 (CI 95% 2.59–2.84) in those aged <30 years compared to 9.11 (CI 95% 8.55–9.70) in women aged ≥40 years. Advanced maternal age (Hazard Ratio (HR, 95% confidence interval) CI 95%: 3.34 (3.08–3.62)), use of antihypertensives (1.49 (1.21–1.84), and use of drugs classified as D or X during pregnancy (1.17 (1.07–1.29)) showed to be positive predictors associated with increased risk of miscarriages. (4) Conclusion: BIFAP database can be used to identify women suffering from miscarriages, which will serve to further study risk factors associated with miscarriages with special attention to drug utilization.

Drug Prescription Profiles in Patients with Polypharmacy in Spain: A Large-Scale Pharmacoepidemiologic Study Using Real-World Data

We aimed to identify and compare medication profiles in populations with polypharmacy between 2005 and 2015. We conducted a cross-sectional study using information from the Computerized Database for Pharmacoepidemiologic Studies in Primary Care (BIFAP, Spain). We estimated the prevalence of therapeutic subgroups in all individuals 15 years of age and older with polypharmacy (≥5 drugs during ≥6 months) using the Anatomical Therapeutic Chemical classification system level 4, by sex and age group, for both calendar years. The most prescribed drugs were proton-pump inhibitors (PPIs), statins, antiplatelet agents, benzodiazepine derivatives, and angiotensin-converting enzyme inhibitors. The greatest increases between 2005 and 2015 were observed in PPIs, statins, other antidepressants, and β-blockers, while the prevalence of antiepileptics was almost tripled. We observed increases in psychotropic drugs in women and cardiovascular medications in men. By patient´s age groups, there were notable increases in antipsychotics, antidepressants, and antiepileptics (15–44 years); antidepressants, PPIs, and selective β-blockers (45–64 years); selective β-blockers, biguanides, PPIs, and statins (65–79 years); and in statins, selective β-blockers, and PPIs (80 years and older). Our results revealed important increases in the use of specific therapeutic subgroups, like PPIs, statins, and psychotropic drugs, highlighting opportunities to design and implement strategies to analyze such prescriptions’ appropriateness.

Evaluation of the Risk of Inflammatory Bowel Disease after the HPV Vaccination in Primary Care in Spain: A Time-Varying Cohort Analysis of Around 390,000 Girls

INTRODUCTION

A link between the human papillomavirus vaccination (HPVv) and inflammatory bowel disease (IBD) has been suggested.

OBJECTIVE

We aimed to estimate the risk of IBD following HPVv compared with periods not exposed to the vaccines.

METHODS

Primary healthcare records (Spanish Primary Care Database For Pharmacoepidemiological Research [BIFAP]) were used in a cohort study of girls in Spain aged 9-18 years between 2007 and 2016 free of IBD or HPVv at study entrance. During the follow-up to IBD diagnosis, time-varying HPVv exposure and confounders were assessed in Cox models to estimate the hazard ratio (HRs) of IBD in the 2 years after HPVv (exposed period) and thereafter (post-exposed) compared with the no exposure periods. In a post hoc analysis, we moved the IBD date back 30 days as a theoretical delay in diagnosis confirmation.

RESULTS

The cohort comprised 388,669 girls; 154,174 of these received the HPVv, and 88 IBD cases occurred (55 non-exposed, 22 exposed [after first N = 6, second N = 2, or third N = 14 dose] and 11 in post-exposed periods). The adjusted HR was 1.66 (95% confidence interval [CI] 0.68-4.05) for exposed and 1.10 (95% CI 0.37-3.24) for post-exposed periods. The HR for the first dose was 3.94 (95% CI 1.19-13.02). No association was found for the second or third doses. Post hoc, the HR was 1.83 (95% CI 0.72-4.69) for exposed periods (N = 18), and 1.84 (95% CI 0.35-9.83; N = 2), 1.50 (95% CI 0.40-5.63; N = 4) and 1.98 (95% CI 0.71-5.49; N = 12) after the first, second and third doses, respectively.

CONCLUSIONS

This study did not show an increased risk of IBD following 2 years of HPVv exposure. However, an increased risk of IBD diagnosis was observed following the first vaccination dose (1-34 days), which is likely attributable to the clinical recommendation to vaccinate upon onset of IBD symptoms.

Antihistamines and azithromycin as a treatment for COVID-19 on primary health care - A retrospective observational study in elderly patients

Between March and April 2020, 84 elderly patients with suspected COVID-19 living in two nursing homes of Yepes, Toledo (Spain) were treated early with antihistamines (dexchlorpheniramine, cetirizine or loratadine), adding azithromycin in the 25 symptomatic cases. The outcomes are retrospectively reported. The primary endpoint is the fatality rate of COVID-19. The secondary endpoints are the hospital and ICU admission rates. Endpoints were compared with the official Spanish rates for the elderly. The mean age of our population was 85 and 48% were over 80 years old. No hospital admissions, deaths, nor adverse drug effects were reported in our patient population. By the end of June, 100% of the residents had positive serology for COVID-19. Although clinical trials are needed to determine the efficacy of both drugs in the treatment of COVID-19, this analysis suggests that primary care diagnosis and treatment with antihistamines, plus azithromycin in selected cases, may treat COVID-19 and prevent progression to severe disease in elderly patients.

The recording and prevalence of Inflammatory bowel disease in girls' primary care medical Spanish records

PURPOSE

Inflammatory bowel disease (IBD) recording validation among girls in the Spanish Primary Care Database For Pharmacoepidemiological Research (BIFAP).

METHODS

In this observational study, girls aged 9 to 18 years registered in BIFAP between 2002 and 2016, were followed up until there was a recorded IBD diagnosis or a referral to specialist indicating IBD. Anonymized profiles were reviewed to retrieve diagnosis confirmation (a positive colonoscopy or biopsy, specialist, or physician's comments mentioning the IBD diagnosis) or discarding (negative procedure results, alternative diagnosis, or family history). "possible" IBD were profiles missing that evidence, or had suspected IBD. The prescriptions of intestinal anti-inflammatory agents, azatioprine, and mercaptopurine were collected. The prevalence of IBD was estimated after review.

RESULTS

Out of 480 634 girls, 323 had a first ever recorded IBD, of which, 37.8% (N = 122) were "confirmed" incident IBD diagnosis, 19.8% (N = 64) discarded and 38.7% (N = 125) "possible" IBD. Additionally, 12 IBD records (3.7%) referred to prevalent IBD. Prescriptions were recorded in 94.3% (confirmed), 63.2% (possible), 83.3% (prevalent), and 3.1% (discarded) IBD cases. Prevalence was 52.83 "confirmed" or 93.58/10⁵ girls when "possible" IBD were added.

CONCLUSIONS

For a third of the girls, the first recorded IBD included evidence confirming the diagnosis while most of those with missing evidence had treatment indicated for IBD. For research focused in sensitivity, an algorithm including "possible" plus "confirmed" episodes is recommended, whereas only "confirmed" to guarantee higher predictive value. Prevalence suggests that IBD is not a rare disease among girls.