October 2009
Reviewer: Jeff C. Huffman, MD
Generalized anxiety disorder is associated with metabolic syndrome in the Vietnam Experience Study
Background: Both depression and anxiety have been associated with the development of — and death from — cardiovascular disease. There has been limited evidence suggesting a link between major depression (MDD) and metabolic syndrome, but additional assessment of this link has been needed, and there had been no prior study of the association between GAD and metabolic syndrome.
Methods: This cohort was the same as the previously described Vietnam Experience Study cohort (Phillips, et al, reviewed here). During the medical examination in 1986, in addition to undergoing interview assessments for MDD and GAD, subjects had bloodwork, blood pressure monitoring, and height and weight data to calculate BMI. The primary outcome variable was the presence of metabolic syndrome; multiple demographic, psychosocial, and medical variables were also included in the analysis.
Results: Seven hundred seventy-three (18%) of the subjects had metabolic syndrome at the time of the medical evaluation. MDD was not associated with metabolic syndrome, but GAD was significantly associated with metabolic syndrome, independent of all covariables (odds ratio 1.4; p=0.02).
Discussion: As with the preceding article, these findings raise important questions about the importance of anxiety (GAD) in the development of cardiovascular conditions. Furthermore, given the high rates of comorbidity between MDD and GAD, these results make us question whether prior studies that found links between depression and metabolic syndrome — but did not measure GAD — were actually missing the "true" link between GAD and metabolic syndrome.
Again, the generalizability of these results may be limited by the limitations of the cohort regarding its selective nature, male population, and unusually high rates of GAD. Furthermore, this study measured psychiatric symptoms and metabolic factors contemporaneously, making it difficult to make any argument about one condition causing the other. Further study of the impact of GAD on cardiovascular health is clearly needed.