Dr. Anne Trontell of the Food and Drug Administration (FDA) gave three examples of surveillance: drug-based, setting-based, and outcome-based. Drug-based surveillance occurs when clinicians prescribe a new drug product and actively report on patient safety. This approach examines populations of interest after the launch of a product. It is similar to the United Kingdom’s prescription event monitoring system that follows the first 10,000 users of a new product. Japan’s health-care system also engages in active surveillance in the first six months of a product’s marketing. The UK and Japanese systems could serve as potential models for the United States in postmarketing surveillance.
Dr. Trontell discussed setting-based surveillance as another way to capture ADEs. Drug-associated adverse events may present or otherwise be concentrated in certain health-care facilities. Setting-based surveillance systems in hospitals, emergency room departments, or pharesis centers may help detect relevant drug-related events. Dr. Trontell also noted that the FDA, in collaboration with the Centers for Disease Control and Prevention (CDC), the Consumer Product Safety Commission (CPSC), and the National Electronic Injury Surveillance System (NEISS), looks at its ability to detect drug-related injuries that present to emergency departments.
The National Electronic Injury Surveillance System: Cooperative Adverse Drug Events Surveillance (NEISS-CADES) is a nationally representative subsample of 64 of 98 NEISS hospitals selected as a sample of U.S. hospitals (CDC, 2005). At each of the hospitals, coders review all emergency department charts for ADEs. The case definition excludes drug withdrawal, drug abuse, self-harm attempts, lack of therapeutic effect, and effects of medications administered in the emergency department. This system captures prescription and over-the-counter medications, vaccines, vitamins, and nutritional supplements.
The final area Dr. Trontell discussed was outcome-based surveillance of selected health outcomes that are often associated with drug toxicity. For example, the FDA is working with the Drug-Induced Liver Injury Network (a network of liver transplant centers) to solicit information about antecedent drug exposures in individuals who are listed for or require a liver transplant. Such a system may identify individual agents or combinations thereof that are associated with hepatotoxicity.
Dr. Kilbridge reported that in the Duke University adverse event detection system, even with strong encouragement to report adverse events, approximately one out of every six events is logged into the