New Directions in Public Health Surveillance: Using Electronic Health Records to Monitor Chronic Disease

Public health is an information business. Whether acquiring information to inform policy and programs or disseminating information so others can make informed decisions, public health depends upon timely, accurate, and complete information. As noted in this issue of the journal, public health surveillance and informatics have been central sources of information for public health leaders for decades. In other Management Moment columns,^1,2 we have offered the vision of the “informatics-savvy health department” in which innovative approaches to collecting and using information to guide public health programs were described. In this column, we offer a new direction in public health surveillance as practiced in informatics-savvy health departments in which data from electronic health records (EHRs) are used for chronic disease surveillance. Public health leaders play a central role in this pioneering work by supporting staff to address technical issues and in fostering information partnerships with the health care system to create networks of innovation in public health informatics.

Electronic Health Records—A New Source of Surveillance Data for Public Health

Over recent years, public health leaders have come to appreciate that timely, detailed clinical data about chronic disease screening, diagnosis, treatment, and control exist in EHRs. Vast repositories of detailed clinical data reside within health systems, health information exchanges, and other health data aggregators. Getting access to detailed clinical data, and, more importantly, creating ongoing information partnerships with the holders of such data, is a high-value opportunity for public health today, an opportunity for which the path consists largely of relationship building and governance. However, a range of technical challenges must be addressed to realize this potential.

Addressing Technical Challenges

In recent years, specialists in public health informatics have piloted multiple approaches to extracting EHR data and transforming it for public health surveillance; a few examples that have potential for widespread use are highlighted here. The Colorado Health Observation Regional Data Service (CHORDS) is a distributed data network that links EHR data across health care and behavioral health providers in the Denver metro area.^3–5 CHORDS generates prevalence maps such as adult and adolescent depression, adult hypertension, and pediatric obesity at the census tract level for public use.⁶ In New York City, the Macroscope project^7,8 tested the use of EHR data from primary care providers for surveillance. By conducting a comparison of chronic disease prevalence estimates between EHRs and surveys, the Macroscope found high sensitivity and specificity for obesity and diabetes prevalence and modest to high specificity and sensitivity for hypertension, tobacco use, and hyperlipidemia. In another pioneering project, researchers at Harvard Medical School developed Electronic medical record Support for Public Health (ESP) and RiskScape, which were first implemented as a distributed network used by the Massachusetts Department of Public Health, a project known as MDPHnet,^9,10 and has now been replicated in other jurisdictions. ESP transforms EHR data into public health indicators through condition-specific algorithms such as diabetes, smoking, and hypertension prevalence and control. RiskScape processes these data to visualize geographic, demographic, and temporal surveillance trends (see Figures 1 and 2 that reflect test data). While each project had different methods and outputs, all 3 demonstrated that EHR data could be accessed successfully and transformed into meaningful surveillance information.

FIGURE 1: RiskScape Dashboard of Chronic Disease Risk Factors^aAbbreviation: BMI, body mass index.^aThe estimates reflect test data and are not intended for surveillance use. This figure is available in color online (www.JPHMP.com).

FIGURE 2: Prevalence of Hypertension by County^{a a}The estimates reflect test data and are not intended for surveillance use. This figure is available in color online (www.JPHMP.com).

Creating a Widespread Network of Informatics Innovation

With pilot funding from the Centers for Disease Control and Prevention (CDC), the National Association of Chronic Disease Directors (NACDD) has created a network of public health informatics innovators to expand the practice of using EHR data for surveillance of chronic disease risk factors—the Multi-state EHR-based Network for Disease Surveillance or MENDS.¹¹ MENDS is a distributed surveillance system that provides timely estimates of the epidemiology of chronic diseases using detailed clinical data drawn from EHRs nationwide. MENDS can be accessed by health departments and other authorized users for informing policies, monitoring trends, planning programs, and evaluating outcomes. MENDS has recruited data aggregators to act as stewards of data from health care organizations and provide operational, research, and quality improvement services. Public health leaders in participating states can then use RiskScape's online dashboard to track rates of chronic disease prevalence, risk factors, and control (Figure 1) among large populations. These data can be used to create chronic disease prevalence maps at the county and zip code levels (Figure 2).

By participating in MENDS, health departments, health care organizations, and data aggregators work together, using visualization tools that apply a chronic disease epidemiology lens to generate surveillance insights. By accessing data from data aggregators, the MENDS system leverages existing relationships between public health agencies and health care delivery systems using a technical infrastructure and data curation tools that delivery systems have already implemented. Forging these relationships often requires the direct intervention of a senior public health leader.

Forming Information Partnerships

The future of public health practice will depend in large measure on the formation of mutually beneficial strategic partnerships.¹² The prevention of chronic disease on a population level represents a compelling opportunity to form such partnerships. To begin with, what do we mean by information partnerships? For our purposes, these are formal arrangements in which health departments—local, regional, state, and tribal—have access to the rich benefits of clinical data to answer pressing population health questions, questions in which ideally the owners or stewards of the clinical data also have an interest.

Sharing clinical data from the EHR with an outside organization such as a health department requires addressing different governance and legal challenges. Forging an information partnership requires building trust, navigating HIPAA, and overcoming legal and policy hurdles. It is the responsibility of the health care organization and data aggregators to protect clinical data. Data sharing outside of treatment, payment, or operations requires additional documentation, agreements, assurances, and security measures, for which the receiving organization is responsible. There are 3 key components of an effective information partnership that public health leaders will need to address:

• First, building a compelling, win-win value case, providing the rationale for why and how the partnership will lead to enduring value for both parties, thus making the costs in time and perhaps money worthwhile.
• Second, once the decision to share data has been made, effective governance structure, policies, and processes are needed to clarify how decisions will be made, define respective roles and responsibilities, define allowable uses of the data, and establish ownership of data products. Data sharing agreements will almost certainly be a principal artifact of establishing governance.
• A third less tangible but no less critical element is trust. There is a saying that data sharing happens at the speed of trust,¹³ a saying likely to be endorsed by anyone participating in such exchanges. Building trust takes time, and it may involve the active and consistent participation of public health leadership until it is established.

Summary

The oceans of detailed clinical data are teeming with potential for public health. The increasing focus on population health within the health care community has created curiosity and desire for public health surveillance methods, tools, partnerships, and insights. Information partnerships between public health and health care present opportunities to answer many surveillance questions that have been unanswerable in the past. Examples include actively monitoring disease control, prescribed treatments, and health care utilization for people with chronic diseases. In addition, health information exchanges and data aggregators are powerful assets to provide technical infrastructure and data contribution services with public health. Obtaining access to such data requires the creation of a win-win value proposition, establishing sound governance structures and procedures that build and maintain trust, and bringing value to the table in the form of population health, epidemiologic, and analytic expertise to prevent and manage chronic disease in communities and nationally.