A greater reduction in high-frequency heart rate variability to a psychological stressor is associated with subclinical coronary and aortic calcification in postmenopausal women

Abstract

Objective: Reduced cardiac parasympathetic activity, as indicated by a reduced level of clinic or ambulatory high-frequency heart rate variability (HF-HRV), is associated with an increased risk for atherosclerosis and coronary artery disease. We tested whether the reduction in HF-HRV to a psychological stressor relative to a baseline level is also associated with subclinical coronary or aortic atherosclerosis, as assessed by calcification in these vascular regions.

Method: Spectral estimates of 0.15 to 0.40 Hz HF-HRV were obtained from 94 postmenopausal women (61-69 years) who engaged in a 3-minute speech-preparation stressor after a 6-minute resting baseline. A median of 282 days later, electron beam tomography (EBT) was used to measure the extent of coronary and aortic calcification.

Results: In univariate analyses, a greater reduction in HF-HRV from baseline to speech preparation was associated with having more extensive calcification in the coronary arteries (rho = -0.29, p = .03) and in the aorta (rho = -0.22, p = .06). In multivariate analyses that controlled for age, education level, smoking status, hormone therapy use, fasting glucose, high-density lipoproteins, baseline HF-HRV, and the stressor-induced change in respiration rate, a greater stressor-induced reduction in HF-HRV was associated with more calcification in the coronary arteries (B = -1.21, p < .05), and it was marginally associated with more calcification in the aorta (B = -0.92, p = .09).

Conclusion: In postmenopausal women, a greater reduction in cardiac parasympathetic activity to a psychological stressor from baseline may be an independent correlate of subclinical atherosclerosis, particularly in the coronary arteries.

Figures

Figure 1

Unadjusted mean change (± standard error of mean) in high-frequency heart rate variability (HF-HRV) from a resting baseline to a speech preparation task in 79 postmenopausal women with Agatston calcium scores falling in the lower, middle, and upper tertiles of the coronary (bottom) and aortic (top) calcium score distributions. The range of calcium scores for each tertile is shown in parentheses along the abscissa. Changes in HF-HRV to the speech preparation task were assessed a median of 282 days (range, 0–754 days) before coronary and aortic calcium scores were obtained.