Background: We tested the hypothesis that pressure sensitivity of the sternum (PPS) is associated with autonomic nervous system (ANS) function as assessed by tilt table test (TTT). in patients with stable ischemic heart disease.
Objectives: (1) To evaluate an association between PPS and systolic blood pressure (SBP) and heart rate (HR) responses to TTT; and (2) to test the hypothesis that a reduction of resting PPS raises the PPS, SBP and HR responses to TTT response and lowers risk factors for ANS dysfunction (ANSD).
Methods: Cross-sectional study: In 361 patients with stable ischemic heart disease we measured PPS, SBP, and HR during TTT. Intervention study: We reassessed subjects with persistent stress who concluded a stress intervention trial by a second TTT.
Results: Cross-sectional study: Resting PPS and the PPS response to TTT were correlated (r = - 0.37). The PPS response to TTT was correlated with that of SBP (r = 0.44) and HR (r = 0.49), and with the number of risk factors for ANSD (r = - 0.21) (all p < 0.0001). Intervention study: A reduction in resting PPS was associated with an increment in PPS response to TTT (r = - 0.52, p < 0.0001). The greater this increment, the greater was the reduction in ANSD risk factors (r = - 0.23; p = 0.003).
Conclusion: The results are consistent with the hypothesis that PPS at rest and in response to TTT reflects ANS function.
Keywords: Autonomic nervous system dysfunction; depression; pressure pain sensitivity; pressure pain threshold; stress; tilt table test.