various inflammatory pathways that link oral infections disease have provided significant evidence of interrelat-
such as periodontitis to systemic damage. These etiologi- ed etiological pathways. When carefully examined, these
cal mechanisms include metastatic spread of gram-nega- pathways yield multiple opportunities for preventive or
tive bacteria that gain access to the vasculature through early therapeutic intervention of a cluster of multi-fac-
a breach of the compromised epithelial lining of peri- torial chronic diseases like diabetes, atherosclerosis-in-
odontal pockets and metastatic injury from the effects duced diseases, and periodontitis. Adopting a syndemic
of the circulating toxins of periodontal pathogens. ²⁵ The orientation to the epidemic of obesity, insulin resistance,
result is metastatic inflammation caused by immunologic diabetes and related inflammatory conditions may pro-
response to the pathogens and their toxins. ²⁵ Infection vide the best blueprint for health-promotion and risk-
within the periodontium may be the origin of vascular modification strategies that disrupt the cycle of immuno-
dissemination of large numbers of virulent pathogenic inflammatory events. These types of interventions hold
bacteria to distant sites in the body, ²⁶ thereby increas- the greatest promise for sustainable healthcare.
ing the burden of systemic inflammation seen in several
chronic disease states, including diabetes. Syndemic is a relatively new term introduced in 1994 by
Singer²⁸ to describe a set of 2 or more linked health prob-
Another pathobiological concept that may be unfamiliar lems acting synergistically to contribute to the excess
to many within the dental and medical communities is burden of disease in a population. ²⁸ Although the term is
the relationship between infection seen in periodontal generally used in a public healthcare context to describe
disease, insulin resistance, and the risk of chronic inflam- intertwined and mutually enhancing health and social
matory conditions. This relationship is best described by problems, Singer used it to describe mutually reinforc-
a conceptual model proposed by Donahue and Wu, ²⁷ who ing connections between substance abuse, violence, and
theorized that there is a pathobiological mechanism to AIDS. ²⁹ A syndemic orientation is primarily distinguished
support a role for periodontitis and insulin resistance in from other healthcare perspectives by its explicit empha-
increasing risk for diabetes and coronary heart disease sis on examining the connections between health-related
(CHD). Simplified, oral infections such as chronic peri- problems. ²⁹
odontitis could trigger low-level inflammation leading
to increased cytokine production and enhanced insulin Traditionally, research, disease prevention, public health
resistance. ²⁷ Insulin resistance increases the risk for practices, and healthcare policy have focused on a single
both type 2 diabetes and CHD. ²⁷ Once established, dia- disease, even when evidence suggested interrelation-
betes and CHD may subsequently induce feedback which ships. ²⁹ The term syndemic may aptly apply to the inter-
amplifies the immune and inflammatory responses. ²⁷ If related cluster of chronic inflammatory disease states
this hypothesis is proven, such a cycle of immuno-inflam- that may amplify one another and to the forces (environ-
matory events would provide multiple opportunities for mental and acquired risk factors) linking those disease
interventions potentially mitigating the risk for diabetes states together. ²⁹ Diabetes, obesity, insulin resistance, hy-
and CHD. pertension, hyperlipidemia, and genetically-encoded hy-
perinflammatory response to infection (i.e., periodontal
The overarching precept is that medical and dental pro- infection) are part of this cluster of diseases brought on
fessionals have common goals: preventing chronic inflam- by chronic inflammation. These syndemic relationships
mation and enabling interventions that disrupt the cycle are represented in Figure 1.
of immuno-inflammatory events. All healthcare providers
need to understand the role of inflammation in the link A syndemic orientation has the potential to provide a
between periodontal disease and systemic diseases such framework that can guide initiatives of greater efficien-
as diabetes and CVD. It is essential that medical provid- cies and effectiveness because healthcare providers will
ers recognize infections of oral origin as significant risk no longer approach chronic diseases as discrete prob-
factors for systemic inflammation. lems. Instead, diseases will be viewed as a cluster of
chronic diseases resulting from multiple forces (envi-
Utilizing a Syndemic Orientation to Devise ronmental and acquired risk factors) that bind the con-

Health-Promotion and Risk-Modification Strategies ditions together. As long as outcomes are measured as
Decades of research related to the sequelae of chronic in- reductions in specific diseases rather than as a cluster
flammatory conditions such as diabetes and periodontal of interrelated chronic conditions, there will be no incen-