Approaches to chronic disease and chronic care: From oxymoron to modern zeitgeist

The increasing prevalence and cost of chronic diseases and care indicate that comprehensive changes and paradigm shifts are needed in how healthcare systems approach and care for the chronically ill. Biological systems theory has been suggested as a model to explain human differences within surrounding systems that could translate into biological mechanisms, and is consistent with the chronic care model. Biological systems theory defines five levels of environmental contexts within the social milieu of an individual: the microsystem, comprising the direct interactions and intimate relationships of an individual's everyday life; the mesosystem, relating to interactions between the components of the microsystem; the exosystem, comprising the wider social and community setting; the macrosystem, consisting of cultural value, ethnic identity, beliefs, laws, and customs; and the chronosystem, comprising the patterns of events throughout the lifecourse. Interventions incorporating biological systems theory have shown some success in pediatric populations. Bioecological systems theory presents an out-of-the-box discipline approach for potential application or contribution to chronic care that is consistent with the chronic care model.