AIDS and Behavior

, Volume 20, Issue 2, pp 423–430 | Cite as

Syndemics and Health Disparities: A Methodological Note

  • Alexander C. Tsai
  • Atheendar S. Venkataramani
Original Paper


In the theory of syndemics, diseases are hypothesized to co-occur in particular temporal or geographical contexts due to harmful social conditions (disease concentration) and to interact at the level of populations and individuals, with mutually enhancing deleterious consequences for HIV risk (disease interaction). Since its original elaboration more than 20 years ago, the epidemiological literature on syndemic problems has followed a questionable trajectory, stemming from the use of a specific type of regression model specification that conveys very little information about the theory of syndemics. In this essay we critically review the dominant approaches to modeling in the literature on syndemics; highlight the stringent assumptions implicit in these models; and describe some meaningful public health implications of the resulting analytical ambiguities. We conclude with specific recommendations for empirical work in this area moving forward.


AIDS/HIV Social determinants 



The authors acknowledge salary support through U.S. National Institutes of Health K23MH096620 (A.C.T.). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Alexander C. Tsai
    • 1
    • 2
    • 3
  • Atheendar S. Venkataramani
    • 1
    • 2
    • 4
  1. 1.MGH Global HealthMassachusetts General HospitalBostonUSA
  2. 2.Harvard Center for Population and Development StudiesCambridgeUSA
  3. 3.Mbarara University of Science and TechnologyMbararaUganda
  4. 4.Division of General Internal Medicine, Department of MedicineMassachusetts General HospitalBostonUSA

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