Analysis of Adverse Events Reports Submitted to the Food and Drugs Administration of the United States of America (2007-2012)

Abstract

Background: Many nations collect data on adverse events (AEs) associated with the use of drugs using what is generally referred to as the Spontaneous Reporting System (SRS) [1,2,3]. Analysis of such data is important in discovering hitherto unknown problems associated with drug use and in understanding the features of the variables related to the problem of adverse drug reactions (ADRs) [4,5,6]. The SRS of the Food and Drugs Administration (FDA) of the United States of America (US), known as the FDA Adverse Event Reporting System (FAERS) [3], is probably the largest system for collecting data on AEs associated with drug use.
 Objectives: (i) Find any trends in the variables associated with the problem of adverse events in drug use, (ii) Elucidate some of the issues raised in the literature by way of the evidence provided by the data, (iii) Find the drugs that were most cited as principal suspect in adverse events and (iv) Examine the data for any other notable attributes.
 Methods: Quarterly Extracts from the FAERS database covering the period 2007 to 2012, which is publicly available on the website of the Food and Drugs Administration (FDA, US), were analysed. Out of the over fifty (50) variables contained in the extracts, fourteen (14) of them, which were thought to be relevant to the objectives of the study, were examined. Owing to the nature of the data, the tools of frequencies, proportions and averages were used in the analysis of it.
 Results: The results of the analysis revealed that for the period 2007 – 2012, the reported cases of adverse events almost tripled (2.7 times), with annual growth rate of 22.1%. Reports on female subjects dominated throughout the period, accounting for a little over two-thirds of the reported cases annually and in the overall number of reports for the period. The proportion of cases that resulted in death appeared to be increasing over time. Non-health professionals are almost as likely as health professionals to report adverse events. Expedited reports (concerning events that are unexpected, from the perspective of the known pharmacology of the suspect drug(s)) accounted for the highest number of cases throughout the period. A large proportion of the cases were reported electronically with an indication of increasing trend over the period under review and in the years following. The age group most involved in adverse events associated with drug use is 45 – 64, followed by the age groups 65 and over, 45 – 59, 18 – 44 and 0 – 17 in descending order of involvement when looked at from the point of view of number of reported cases. However the results of the analysis show that susceptibility to adverse events increases with age; the older one gets the more vulnerable one becomes to adverse events involving drug use. The analysis also revealed that some of the problems that prevent the best use of SRS data, such as missing values for age and sex, mentioned in the literature, existed during the period under consideration [7,8,9].
 Conclusion: It is essential to encourage reporting of adverse events, especially accurate and prompt reporting. This is indispensable in dealing with the problem of adverse events in medication use comprehensively; as it not easy to obtain data on the variables involved with the problem through other means and SRS data provide useful insights, especially when keying out factors that contribute to the occurrence of adverse events associated with drug use.

Analysis of Data on Adverse Drug Events Reported to the Food and Drugs Administration of the United States of America

“…One could infer that the proportion of reported cases of adverse events that resulted in death and hospitalization (including those that warranted extension of hospital stay) were at least 8.2% and 20.1% respectively for the 2013 to 2018 period. These values are quite close to the respective values of 7.6% and 21.4 obtained for the 2007 to 2012 period [16].…”

“…further less when the latter has been adjusted for potential drug use (7.6 percentage point difference, Table 8 and Figure 8). These observations are a marked departure from results obtained in the analysis reported in the paper covering the 2007 to 2012 period [16] and the results obtained by Moore et al [18]. It is significant to note that the value of p increases with age (down the table).…”

“…As seen in the results of the analysis presented above, the number of adverse events reported to the FDA (US) grew at an average annual rate of 15.8% for the 2013 to 2018 period. This growth rate is lower than the 22.1% per annum observed for the 2007 to 2012 period [16]; which may be indicating that the rate of reporting may have, on the whole, slowed down during the 2013 to 2018 period, compared to that of the 2007 to 2012 period. It could also be that in LAERS, the system did not recognise some of the duplicate reports as such, passing them off It is worth noting that more reports were received for the 2013 to 2018 period than for the 2007 to 2012 period [16] as the total number of reports (6,714,463) received for the 2013 to 2018 period is approximately 2.7 times the number of reports (2,483,936) The rate of growth of the number of death which appeared to be increasing in the 2007 to 2012 period seem to have stabilized as the proportion of deaths relative to both the overall number of reports and the non-missing cases seem to hover around 9% and 17% respectively (Figure 3).…”

“…Section 3 presents the results of analysis of data covering the 2013 to 2018 period with some initial DOI: 10.4236/ojs.2020.102015 205 Open Journal of Statistics discussion. Section 4 presents a discussion of the findings for the 2013 to 2018 period in full, and compares the findings with that of the 2007 to 2012 period [16]. Some thoughts on the implications of the findings for pharmacovigilance form the concluding section, Section 5.…”

“…The study reported in this paper was intended to identify and describe the trends in the variables associated with the problem of adverse events in medication use during the 2013 to 2018 period and to compare them with that of the 2007 to 2012 period [16], particularly whether the transition from an old system of organising the data to a new one by the FDA (US) has had any effect on the trends observed in the variables. Specifically, the objectives of the study were to: i) explore the trends in the variables involved with the adverse events problem in the 2013 to 2018 period and compare these trends with that found in the study covering the 2007 to 2012 period; ii) determine whether or not the level of missing variable values in the 2013 to 2018 period is lower than, the same or higher than it was in the 2007 to 2012 period; iii) find out how the first twenty principal suspect drugs most cited to be involved in adverse events occurring during drug use in the 2013 to 2018 period compare with that of the 2007 to 2012 period.…”