The development of depressive symptoms during medical internship stress predicts worsening vascular function

We sought to prospectively determine whether the onset of internship stress and any subsequent depression alters physiological markers of early vascular disease

We explored potential mechanisms linking stress and depression to vascular disease in a prospective cohort of 37 participants exposed to medical internship stress, an established precipitant of depressive symptomatology.

Change in depressive symptom score from baseline over one year of internship stress was inversely correlated with change in the reactive hyperemia index (RHI), a measure of peripheral endothelial function (r=0.41, p=0.01). The change in depressive symptoms in the first six months of internship was similarly related to change in RHI over one year (r=0.38, p=0.02). While the development of depressive symptoms did not significantly impact changes in endothelial progenitor cells (EPCs), EPCs did significantly decrease with the year of internship stress (11.9 to 3.4cells/ml blood; p=0.01).

Endothelial function may be a critical link between stress, depression, and cardiovascular disease and a feasible surrogate outcome for prospective studies.