Pick up almost any article about population health and you may well find the topic confused with the concept of community health. They are, in fact, related but different terms, and the implications of the differences are significant for health systems.

Population Health

Population health has to do with accountability for the healthcare outcomes and costs of caring for a defined population of people.

The population is most often defined by contract – it might be the insureds of a particular insurance plan or it might be the employees and beneficiaries of an employer that contracts with the health system to manage the health of its workforce. The accountability results from the incentives and/or penalties associated with the healthcare outcomes and cost in caring for the population as determined by a value-based arrangement. 

Population health is not business as usual under fee-for-service. While health systems typically have many contracts under which a defined population has coverage for care provided by the health system to members of the health plan, fee-for-service ensures payment for each service provided, often without regard to whether that service was necessary, whether there was a more cost-effective service available or whether the patient was harmed by the service. In other words, the providers are not accountable for the healthcare outcomes or cost, even though it is a defined population. 

Community Health

Healthcare planners may define communities as towns, cities, counties or service areas. The health of a particular community can be measured in many different ways, but generally, measures assess the cumulative impact of the social determinants of health, especially personal behaviors (e.g., smoking rates, use of seatbelts and prevalence of alcoholism) and environmental factors (e.g., poverty levels, crime rates, educational levels and access to care).

Health systems can and should contribute to improving community health, but do not generally have the resources or expertise to take accountability for a community’s health.

Implications

Effective population health management is very different from the approaches to community health. Those health systems and hospitals that conflate the two are very likely to be ineffective at population health and ill-prepared for new and emerging pay-for-value arrangements. 

Population health management involves understanding the health risks of the defined population and then segmenting the population into subpopulations.

For St. Luke’s, broad subpopulations are (1) those who are healthy, without identifiable risk factors or known genetic predispositions for a preventable or treatable disease; (2) those who are healthy but have identifiable risk factors or known genetic predispositions to disease; (3) the acutely ill in our hospitals; (4) those with a chronic disease; and (5) those with multiple chronic illnesses. 

Circumscribing subpopulations ensures that interventions are tailored to the specific subpopulation and that limited resources are directed towards those subpopulations that account for the overwhelming majority of the costs and healthcare spending, i.e., subpopulations 4 and 5.

More limited and targeted interventions are directed at subpopulation 2, essentially to mitigate the risk factors and/or to increase screenings for the diseases for which they have increased risk due to their genetic predisposition. For subpopulation 3, we focus our efforts around high reliability, since this is the subpopulation we are most likely to inadvertently and severely harm. 

This approach is distinctly different from our community health initiatives. Our population health strategies are extremely targeted and focused on known individuals with known risks within the defined populations for which we have assumed some degree of financial risk. Our community health initiatives tend to be directed at behavioral or environmental determinants of health, applied broadly to people who are largely unknown to us and may or may not be receiving healthcare services from us. 

While we take accountability for population health, and perform most of those services ourselves or through other providers working in an integrated and transparent manner with us, our community health initiatives tend to be delivered through partnerships with other community organizations and state or local agencies.

For some of these community health partnerships, we are the leader; for others, our main function may be as convener; and for others, we may simply contribute to the efforts of others through grant or other indirect support. 

Population health contributes to community health. As a general rule, about 10 percent of a community’s health status is determined through the access to care and services provided by local healthcare providers. 

It is important that those of us who run hospitals and health systems, as well as the boards that oversee these efforts, remain realistic about the relatively minor contribution we make to the health of a community. By the time we see a car accident victim, whether the patient would have had fewer injuries and a better outcome had she been wearing a seatbelt is a moot point. By the time we see a woman in active labor, whether the infant would have been healthier had the mother received prenatal care is a moot point. 

That is not to say that our hospitals and health systems don’t play a critical role in the health of our communities, but I don’t know of any hospital or health system with the resources needed to reach all the members of the communities they serve in their homes, schools and workplaces, and impact all, or even most of, the social determinants of health. 

We need to be experts in population health – if not us, who else is positioned to do this? But we also need to be humbled by the magnitude of the community health challenge, and find partners to work with and through, who often will have a greater understanding of the problems, greater expertise and greater competencies with which to address these health challenges. 

When we are very good at population health, the heart of our business, and as a consequence of being successful in value-based contracts, we generate the income that is not only sufficient to reinvest in our people, facilities and technology to drive even better outcomes at lower cost, but also the income that we can devote to community health, which should in turn diminish the proportion of those in subpopulations 4 and 5, who account for so much of our healthcare spending.