Representativeness of diabetes patients participating in a web-based adverse drug reaction monitoring system

Sex Differences in Adverse Drug Reactions of Metformin: A Longitudinal Survey Study

INTRODUCTION

In general, women more often experience metformin-associated adverse drug reactions (ADRs) than men.

OBJECTIVES

We aimed to assess whether sex differences in reported ADRs for metformin are observed at different times after initiation, and to explore their concurrence with sex differences in the dose of metformin over time. This may guide future studies in assessing the involved mechanisms of sex differences in metformin-associated ADRs and may guide sex-specific management of ADRs in clinical practice.

METHODS

This study has a longitudinal design using data about patients initiating metformin collected by the Dutch National Pharmacovigilance Center Lareb through their Intensive Monitoring program. Patients were asked to complete a web-based questionnaire six times after initiation (i.e., at 2 weeks, 6 weeks and at 3, 6, 9, and 12 months). The outcome variables were the proportion of patients reporting any ADR (primary) and the dose of metformin (secondary). Sex differences in the proportions of ADRs and in the dose were tested at each assessment using Pearson Chi-Squared tests and Wilcoxon rank-sum tests, respectively. Using Bonferroni adjustment for multiple testing, a p value < 0.01 was considered statistically significant.

RESULTS

The number of included patients was 1712 (40.9% women). Women reported an ADR more often than men, which was statistically significant at the assessment at 2 weeks (34% vs 25%, p < 0.001), and 6 weeks (37% vs 28%, p = 0.001) after initiation. In general, women were reported to be prescribed a lower dose than men, which became statistically significant at the 9-month assessment (p < 0.01).

CONCLUSIONS

Sex differences in reported ADRs were seen in the first weeks after metformin initiation, whereas statistically significant differences in self-reported prescribed dosing were observed after several months. Patients, in particular women, might benefit from being prescribed lower metformin doses at treatment initiation.

The 2011–2020 Trends of Data-Driven Approaches in Medical Informatics for Active Pharmacovigilance

Pharmacovigilance, the scientific discipline pertaining to drug safety, has been studied extensively and is progressing continuously. In this field, medical informatics techniques and interpretation play important roles, and appropriate approaches are required. In this study, we investigated and analyzed the trends of pharmacovigilance systems, especially the data collection, detection, assessment, and monitoring processes. We used PubMed to collect papers on pharmacovigilance published over the past 10 years, and analyzed a total of 40 significant papers to determine the characteristics of the databases and data analysis methods used to identify drug safety indicators. Through systematic reviews, we identified the difficulty of standardizing data and terminology and establishing an adverse drug reactions (ADR) evaluation system in pharmacovigilance, and their corresponding implications. We found that appropriate methods and guidelines for active pharmacovigilance using medical big data are still required and should continue to be developed.

Intensive Monitoring Studies for Assessing Medicines: A Systematic Review

Introduction: Intensive monitoring (IM) is one of the methods of post-marketing active surveillance based upon event monitoring, which has received interest in the current medicines regulatory landscape. For a specific period of time, IM involves primary data collection and is actively focused on gathering longitudinal information, mainly safety, since the first day of drug use. Objectives: To describe IM systems and studies' data published over 11-years period (2006-2016). Specifically, we reviewed study population/event surveillance, methodological approaches, limitations, and its applications in the real-world evidence generation data. Methods: We completed a systematic search of MEDLINE and EMBASE to identify studies published from 2006 to 2016, that used IM methodology. We extracted data using a standardized form and results were analyzed descriptively. The methodological quality of selected studies was assessed using the modified Downs and Black checklist. Results: From 1,400 screened citations, we identified 86 papers, corresponding to 69 different studies. Seventy percent of reviewed studies corresponded to established IM systems, of which, more than half were prescription event monitoring (PEM) and modified-PEM. Among non-established IM systems, vaccines were the most common studied drugs (n = 14). The median cohort size ranged from 488 (hospitals) to 10,479 (PEM) patients. Patients and caregivers were the event data source in 39.1% of studies. The mean overall quality score was similar between established and non-established IM. Conclusions: Over the study period, IM studies were implemented in 26 countries with different maturity levels of post-marketing surveillance systems. We identified two major limitations: only 20% of studies were conducted at hospital-level, which is a matter of concern, insofar as healthcare systems are facing a lack of access to new medicines at ambulatory care level. Additionally, IM access to data of drug exposure cohorts, either at identification or at follow-up stages, could somehow constitute a barrier, given the complexity of managerial, linkable, and privacy data issues.

Adverse drug event patterns experienced by patients with diabetes: A diary study in primary care

PURPOSE

Little is known about adverse drug events (ADEs) experienced over time during chronic drug use. The purpose of this study was to assess ADE patterns experienced by patients with diabetes.

METHODS

Patients who received an oral glucose-lowering drug completed a daily diary for 13 weeks. The diary asked for experienced symptoms and whether patients related these symptoms to any drug they used. Summaries of Product Characteristics were used to check whether the ADEs were known adverse drug reactions (ADRs) of the drugs used. Patterns of weekly occurring ADEs were assessed with descriptive statistics.

RESULTS

We included 78 patients. Almost half of them reported at least one ADE (N = 36; 46%). In total, 80 ADEs were reported. Of these ADEs, 71 (90%) were known ADRs. ADEs lasted less than 1 week in 27 cases (34%) and between 2 and 12 weeks in 15 cases (19%). The remaining ADEs fluctuated (16 cases; 20%) or persisted (22 cases; 28%) during the entire study period.

CONCLUSIONS

ADEs experienced by patients with diabetes can fluctuate or persist over long periods of drug use.

The value of patient reporting to the pharmacovigilance system: a systematic review

AIMS

Current trends in pharmacovigilance systems are veering towards patient involvement in spontaneous reporting of adverse drug reactions (ADRs). The aim of the current systematic review was to identify what is known and what remains unknown with respect to patient reporting to pharmacovigilance systems.

METHODS

A systematic literature search was conducted in PubMed, CINAHL, Journals@Ovid and the Cochrane Library. Studies were included if they contained: (i) reviews about patient reporting; (ii) evaluation of patient reports to national or supranational pharmacovigilance authorities; (iii) a comparison between patient and healthcare professional (HCP) reports submitted to pharmacovigilance authorities; and (iv) surveys of patient experiences, opinions and awareness about reporting ADRs. The methodological quality of the studies was assessed according to principles of Grading of Recommendations, Assessment, Development and Evaluations (GRADE).

RESULTS

A total of thirty four studies were included. Five of the studies were reviews (two of which systematic reviews), fourteen retrospective observational studies, nine surveys and six applied mixed research methods. Patient reporting has the advantages of bringing novel information about ADRs. It provides a more detailed description of ADRs, and reports about different drugs and system organ classes when compared with HCP reporting. In addition, patients describe the severity and impact of ADRs on daily life, complementing information derived from HCPs. Patient reporting is relatively rare in most countries.

CONCLUSIONS

Patient reporting adds new information, and perspective about ADRs in a way otherwise unavailable. This can contribute to better decision-making processes in regulatory activities. The present review identified gaps in knowledge that should be addressed to improve our understanding of the full potential and drawbacks of patient reporting.

Patient Participation and the Use of Ehealth Tools for Pharmacoviligance

In recent years, pharmacovigilance has undergone some major changes. First, the patient's active role in identifying and describing adverse drug reactions (ADRs) has gained recognition. Second, pharmacovigilance has increasingly incorporated information and communications technology (ICT). Patients can now upload their own reports of ADRs online. Data on intensive medication monitoring are now collected via the Internet and smartphones. Worldwide collection of AEs using smart phones might become the leading technique in Low and Middle Income Countries where broad mobile phone service can be managed cheaper than Internet communication. At the same time, researchers are exploring the potential for data sharing via online forums and Internet search engines. In particular we synthetize the Pros and cons of the various methods for gathering pharmacovigilance data (i.e., Web-based spontaneous reporting of adverse drug reactions; Intensive drug monitoring studies; Analysis of online forum postings; Use of mobile phone systems to monitor drug effects). This article describes these advances and highlights their respective contributions.

Construct and concurrent validity of a patient-reported adverse drug event questionnaire: a cross-sectional study

BACKGROUND

Direct patient-reported information about adverse drug events (ADEs) is important since it adds to healthcare professional-reported information about the safety of drugs. Previously, we developed an instrument to assess patient-reported ADEs in research settings. The aim of this study is to assess the construct and concurrent validity of the questionnaire.

METHODS

Patients on at least an oral glucose-lowering drug completed the ADE questionnaire, the World Health Organization Quality of Life-BREF, and the Treatment Satisfaction Questionnaire for Medication (TSQM). The ADE questionnaire assesses ADEs for any drug that the patient uses. Construct validity was assessed by testing whether patients reporting an ADE had a lower general quality of life and physical health than those not reporting an ADE, using Mann-Whitney U-tests and t-tests (significance level <0.05). For concurrent validity, we tested whether ADEs that patients associate with particular drugs in the ADE questionnaire are documented in the Summary of Product Characteristics (SPC) of those drugs, and whether patients who report an ADE with the use of metformin on the TSQM, mention metformin as a drug associated with an ADE on the ADE questionnaire. Agreement of 70% with the SPC was considered satisfactory. Sensitivity and positive predictive value (PPV) were calculated for the comparison with the TSQM, where 70% was used as the cut-off level for sufficient concurrent validity.

RESULTS

We included 135 patients (mean age 64 years, 35% women). Patients who reported an ADE (N = 37) had a lower general quality of life and physical health than those not reporting an ADE (P < 0.05). For 78 of the 146 reported ADEs (53%), patients mentioned at least 1 particular drug associated with the ADE. After clustering related ADEs, this resulted in 56 patient-reported ADE-drug associations. Of these, 41 (73%) were in agreement with information in the SPC. Finally, the questionnaire had a sensitivity of 38% and PPV of 79% for assessing ADEs associated with metformin.

CONCLUSIONS

The construct validity of the patient-reported ADE questionnaire was sufficient for reporting any versus no ADE, but the concurrent validity was only partly demonstrated. Therefore, the questionnaire needs to be adapted before it can be used.