Background: Major depressive disorder (MDD) is associated with increased cardiovascular risk. Although cardiovascular hyperactivity to stressors (e.g., cold pressor test (CPT)) is common in those with MDD, the aortic hemodynamic (AH) responses to sympatho-stimulation in healthy individuals with higher depressive scores (HDS) are not well understood. We hypothesized that individuals with HDS, compared with those with low depressive scores (LDS), would have greater changes in AH during the CPT.
Methods: Thirty-five male participants (mean age, 22.3±0.7 years) completed a self-report measure of depressive symptoms and were classified as having an HDS or LDS. Radial waveforms were then obtained by means of applanation tonometry. The testing protocol consisted of a 10-minute seated rest, 5 minutes of baseline measurements, a 3-minute CPT, and a 3-minute recovery period.
Results: At baseline, no differences were found between the LDS (n=16) and HDS (n=19) groups on any variables studied. During CPT, there was a significant group-by-time interaction for aortic mean blood pressure (HDS vs. LDS = 107±3mm Hg vs. 96±3mm Hg; P = 0.008); augmentation index (HDS vs. LDS =19% ± 3% vs. 11% ± 2%; P = 0.02), a surrogate of wave reflection; and systolic time interval (HDS vs. LDS = 2295±78mm Hg/s.min(-1) vs. 1919±74mm Hg/s.min(-1); P = 0.001), a marker of myocardial work, such that the HDS group had significantly higher responses than the LDS group.
Conclusions: HDS may be associated with cardiac hyperactivity during sympatho-stimulation, contributing to increased central blood pressure, wave reflection, and myocardial work. Prospective studies to unveil mechanisms explaining increased AH in healthy individuals with high depressive symptomatology are warranted.
Keywords: aortic hemodynamics; augmentation index; blood pressure; cold pressor test; hypertension; major depressive disorder; pulse wave analysis..