What is "syndemic"

n. An aggregation of two or more diseases that interact synergistically within a population.

A syndemic is the aggregation of two or more diseases in a population in which there is some level of positive biological interaction that exacerbates the negative health effects of any or all of the diseases. The term was developed and introduced by Merrill Singer in several articles in the mid-1990s and has since received growing attention and use among epidemiologists and medical anthropologists concerned with community health and the effects of social conditions on health, culminating in a recent textbook. Syndemics tend to develop under conditions of health disparity, caused by poverty, stress, or structural violence, and contribute to a significant burden of disease in affected populations. The term syndemic is further reserved to label the consequential interactions between concurrent or sequential diseases in a population and in relation to the social conditions that cluster the diseases within the population.

The traditional biomedical approach to disease is characterized by an effort to diagnostically isolate, study, and treat diseases as if they were distinct entities that existed in nature separate from other diseases and independent of the social contexts in which they are found. This singular approach proved useful historically in focusing medical attention on the immediate causes and biological expressions of disease and contributed, as a result, to the emergence of targeted modern biomedical treatments for specific diseases, many of which have been successful. As knowledge about diseases has advanced, it is increasingly realized that diseases are not independent and that synergistic disease interactions are of considerable importance for prognosis. Importantly, few studies in the empirical literature have actually tested the hypothesis of syndergistic disease interaction (see "Statistical modeling in research on syndemics" below), which is a significant gap in the literature. Given that social conditions can contribute to the clustering, form and progression of disease at the individual and population level, there is growing interest in the health sciences on syndemics.