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Adverse Event

Adverse Events  


Although there is not a universal definition of “adverse event,” the broadest use of the term is any harm to a patient as a result of medical care or the use of a medical product.

Adverse events encompass so-called "never events," which the National Quality Forum (NQF) identifies as those that “should never occur in a healthcare setting,” and the Centers for Medicare and Medicaid Services’ (CMS’) list of hospital-acquired conditions (HACs) for which Medicare will no longer reimburse hospitals.

A “serious adverse event,” as defined by the Food and Drug Administration (FDA), is one that results in death, a life-threatening condition, requires hospitalization, or causes other serious injury.



The Department of Health and Human Services (HHS) Office of Inspector General (OIG) has produced a series of reports about adverse events in hospitals, reflecting regulators’ increased focus on identifying and preventing their occurrence. See, e.g., Hospital Incident Reporting Systems Do Not Capture Most Patient Harm (OEI-06-09-0091); Adverse Events in Hospitals: Medicare's Responses to Alleged Serious Events (OEI-01-08-00590); Adverse Events in Hospitals: Methods for Identifying Events (OEI-06-08-00221); Adverse Events in Hospitals: Case Study in Incidence Among Medicare Beneficiaries in Two Selected Counties; Adverse Events In Hospitals: State Reporting Systems (OEI-06-07-00471); Adverse Events In Hospitals: Overview Of Key Issues (OEI-06-07-00470).

Although an adverse event often indicates that the care resulted in an undesirable clinical outcome and may involve medical errors, adverse events do not always involve errors, negligence, or poor quality of care and may not always be preventable. Department of Health and Human Services (HHS) Office of Inspector General (OIG), Adverse Events in Hospitals: Methods for Identifying Events (OEI-06-08-00221), citing R.M. Wachter, Understanding Patient Safety, McGraw-Hill, 2008.



Medicare Conditions of Participation require hospitals to track instances of patient harm, but the OIG has found many hospital incident reporting systems often fail to capture the bulk of adverse events that actually occur.

The FDA maintains an Adverse Event Reporting System (AERS), a computerized information database designed to support the agency’s post-marketing safety surveillance program for all approved drug and therapeutic biologic products. See The FDA uses AERS to monitor for new adverse events and medication errors that might occur with these marketed products. Id.

Adverse event reporting to the FDA at the point of care is voluntary for healthcare professionals and consumers. Manufacturers that receive an adverse event report are required by regulation to send the report to the FDA. Id.



Agency Guidance

Adverse events also must be reported in the context of clinical trial research. Effective September 27, 2009, the FDA Amendments Act of 2007 (FDAAA) [as it amends 42 U.S.C. § 282(j)(3)(I)(ii)-(iii)] requires Responsible Parties to submit adverse events information when providing clinical study results of applicable clinical trials to Christina M. Markus, Beverly H. Lorell, M.D., Kelly N. Reeves, and Elaine H. Tseng, King & Spalding, Clinical Trial Registration and Results Disclosure: National Institutes of Health Posts Update Regarding Adverse Event Reporting and Delayed Submission of Results, HEALTH LAWYERS WEEKLY, v. 7, no. 30 (July 31, 2009).



In addition, under HHS regulations, “unanticipated problems,” which can include certain adverse events, during the course of federally funded research must be reported to the overseeing institutional review board and relevant agency officials. See generally 45 C.F.R. pt. 46.