In a recent BMJ editorial, Nicholas Moore and Bernard Begaud outline initiatives to improve pharmacovigilance in Europe. Such initiatives are essential to improving the safety of healthcare because current approaches to detection of serious adverse drug reactions (ADRs) have major limitations. Serious adverse drug reactions are often too rare to be detected in early clinical trials, and may not be detected through post-marketing surveillance for many years. This delay in identifying adverse drug reactions leaves clinicians unaware about the potential risks of the drugs they are prescribing, puts patients at risk of iatrogenic harm, and increases both healthcare costs and the costs of drug development.
The development of databases derived from electronic patient records and hospital administration systems could help to improve the detection of adverse drug reactions. In England, these databases include the General Practice Research Database (GPRD), The Health Improvement Network (THIN) and QResearch, all of which are derived from electronic primary care records; and the Hospital Episode Statistics (HES) database, which is derived from hospital patient administration systems and hospital discharge records.
To illustrate this potential, we used one primary care database (THIN) to investigate the association of myopathy and myalgia with the use of statins. Using a case-crossover design (in which each patient acts as their own control and side-effects are examined in the period while a patient is on a drug compared when they are not), it may have been possible to detect the association with statins as early as 1996 (see the figure below, which shows the relative risk of myopathy & myalgia by year in 16,591 patients using statins or fibrates from 1991–2005). A longer exposure period then allows more precise quantification of the size of the effect with narrowing of confidence intervals. The full results of this study can be viewed in an article published in the medical journal PLoS One.
For adverse drug reactions that result in hospital admission, Hospital Episode Statistics, which cover all inpatient and day case activity in England, offer a method for identifying these admissions. For example, between 1998–2005, the total number of hospital episodes for all diagnoses increased by 14% but the total number of hospital episodes associated with adverse drug reactions increased by 45%.[4] The increase in admissions associated with adverse drug reactions may have due to a number of factors: improving record keeping from increased awareness, a general increase in adverse drug reactions against a background of an increasingly elderly population, the introduction of new drugs, and poly-pharmacotherapy because of increased pressure to prescribe medication for long-term illnesses such as diabetes, heart disease and hypertension. More detailed coding, and better use of HES data and of similar systems elsewhere in Europe, could considerably improve our surveillance of ADRs, as well as allowing the evaluation of interventions to improve the safety of prescribing. These issues and the full results of this study are discussed in an article published in BMC Clinical Pharmacology.
Health systems throughout Europe are investing substantially in information and communication technologies, such as the National Programme for Information Technology in England's NHS. One consequence of this investment could be substantially improved methods of pharmacovigilance, allowing pan-European studies building on the many national studies we have seen to date. For example, the EU-ADR project aims to use data from several European countries to develop improved methods of pharmacovigilance. Coverage of larger populations than allowed by single country and single database studies also increases study power with the potential benefit of earlier and more effective detection of adverse drug reactions.
Source: Improving pharmacovigilance: Use of routinely collected data. BMJ 2010;340:c2403.
The development of databases derived from electronic patient records and hospital administration systems could help to improve the detection of adverse drug reactions. In England, these databases include the General Practice Research Database (GPRD), The Health Improvement Network (THIN) and QResearch, all of which are derived from electronic primary care records; and the Hospital Episode Statistics (HES) database, which is derived from hospital patient administration systems and hospital discharge records.
To illustrate this potential, we used one primary care database (THIN) to investigate the association of myopathy and myalgia with the use of statins. Using a case-crossover design (in which each patient acts as their own control and side-effects are examined in the period while a patient is on a drug compared when they are not), it may have been possible to detect the association with statins as early as 1996 (see the figure below, which shows the relative risk of myopathy & myalgia by year in 16,591 patients using statins or fibrates from 1991–2005). A longer exposure period then allows more precise quantification of the size of the effect with narrowing of confidence intervals. The full results of this study can be viewed in an article published in the medical journal PLoS One.
Health systems throughout Europe are investing substantially in information and communication technologies, such as the National Programme for Information Technology in England's NHS. One consequence of this investment could be substantially improved methods of pharmacovigilance, allowing pan-European studies building on the many national studies we have seen to date. For example, the EU-ADR project aims to use data from several European countries to develop improved methods of pharmacovigilance. Coverage of larger populations than allowed by single country and single database studies also increases study power with the potential benefit of earlier and more effective detection of adverse drug reactions.
Source: Improving pharmacovigilance: Use of routinely collected data. BMJ 2010;340:c2403.
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