VA serves an enrolled population of 7.7 million veterans, their family members, and survivors through its more than 1,300 sites of care, including 154 medical centers. The presence of automated databases and a prescription drug benefit makes VA a promising setting for postmarket drug studies. There are some examples of the use of data from the VA system for studies of the prevalence of AEs (Nebeker et al., 2005) and case-control studies of possible adverse effects of drugs (Shannon et al., 2005). VA and CDER would like to work together to use this resource more broadly, but resource limitations prevent more extensive collaboration. VA populations are included in the research of a few of the CERTs (CERTS, 2006; UI Health Care News, 2006).
There is near-unanimous agreement that the Medicare Modernization Act and the Medicare Part D benefit offer potential new resources for post-marketing drug studies. As of January 2006, an estimated 43 million people on Medicare were eligible to sign up for prescription drug coverage through Part D plans, and the Department of Health and Human Services (DHHS) indicates that 19.7 million beneficiaries were enrolled as of April, 2006 (Kaiser Family Foundation, 2006). Because the elderly are frequent users of multiple medications for concomitant diseases, data from Medicare Part D could play an important role in postmarket drug studies, particularly given the opportunity to create linkages among pharmacy, outpatient, inpatient, physician office, and emergency-department claims. FDA has endorsed a proposal, lacking in detail, to establish a postmarketing surveillance system for prescription drugs that would use billing data and health care information collected from Medicare beneficiaries (Kaiser Family Foundation, 2005). Through the Agency for Healthcare Research and Quality (AHRQ) Developing Evidence to Inform Decisions about Effectiveness (DEcIDE) Network, investigators are developing a methodologic toolbox and data-analytic framework for using population-based claims and administrative data sources in pharmacoepidemiologic and pharmacovigilance research (DHHS and AHRQ, 2006).
This kind of research is labor-intensive, and specialized knowledge is required to use some of the databases. A small number of ODS/OSE epidemiologists and safety evaluators are trained to use the databases directly or to collaborate with other researchers to design and analyze data, and they have limited time to conduct research because of their other responsibilities (such as responding to OND consults, working to develop needed CDER guidances, and preparing for meetings).
The advantages of research using health care databases include the ability to conduct studies of uncommon diseases or understudied populations with respect to drug exposures, minimization of study costs, reduction in the time required to complete a study, and the opportunity to study large numbers of patients. Those systems can also provide valuable information