Achieving meaningful device surveillance: from reaction to proaction.

BY 2004, THE US FOOD AND DRUG ADMINISTRATION (FDA) had received a number of reports of serious complications associated with the use of vascular closure devices during cardiac catheterization procedures. In response, the FDA contracted with the National Cardiovascular Data Registry to conduct a prospective comparative safety study of approved devices. One device was found to pose an increased risk for vascular complications, and the device was subsequently removed from the market. While this was a victory for patient safety and demonstrated the potential for clinical registries to support device surveillance, the study raised questions: Should this safety signal have been detected earlier? What other undetected device safety issues exist? These questions highlight key gaps in the US postapproval device surveillance safety net. It is a reactive system, largely relying on voluntary reporting of potential device problems. This leads to underrecognition and lags in timely evaluation of potential device safety issues in clinical practice. When reports are submitted, the FDA often lacks device usage rates (denominator data) and information on comparative safety among devices to determine if there is a “safety signal. ” Moreover, the agency has limited means to investigate potential safety signals in follow-up studies. What is needed is a proactive US device surveillance system—one with nationally representative data for epidemiologic monitoring and with detailed device, patient, and outcome data to inform rigorous comparative safety studies. Calls for a more proactive system abound. For example, the Institute of Medicine is convening national stakeholders in a series of meetings focused on improving the device approval process and postmarket surveillance. The FDA is working with national strategic partners to develop “sentinel” networks to monitor approved products in clinical practice. However, these are works in progress, and effective, coordinated national device surveillance still hangs in the balance. In this issue of JAMA, Resnic and colleagues report initial results of an automated surveillance tool, contributing to proof of concept for sentinel networks. Applying the tool to a statewide angioplasty registry, the authors simultaneously tracked multiple cardiovascular devices and analyzed their comparative outcomes. They found that one particular drug-eluting stent had significantly higher rates of major adverse cardiac events than its peers. They also detected a potential safety signal for a vascular closure device, although that signal was not validated in sensitivity analyses. Beyond the specific findings, the study by Resnic et al represents an important advance in surveillance methodology. It principally supports the feasibility of automated monitoring for device safety signals. The report also demonstrates the value of using clinical registry data to ensure the appropriate level of detail of device, patient, and outcomes data for comparative safety analyses. In this case, the registry data are also used for public reporting of quality of care in Massachusetts; the data are highly complete and are audited. Furthermore, this investigation demonstrates the value of robust statistical methods in comparative safety evaluations using observational data, such as propensity matching and sensitivity analyses, supporting responsible interpretation of potential safety signals. At the same time, this study reinforces how far the United States is from achieving proactive device surveillance. The study was conducted in a single state and despite pooling data from a 4-year period had limited power to compare the outcomes of many devices. The study also used an arbitrary boundary for identifying device safety signals, and additional work is needed to evaluate how different thresholds influence the signal-to-noise ratio of the system. Input from clinicians about any device problems they encountered were not available; such point-of-care reports could complement the epidemiologic data in associating device problems with adverse outcomes. Moreover, despite the robust analytic methods used, the study is observational, and there remains the possibility of unmeasured confounding. Additional studies are needed to determine if the findings represent a true safety signal.