Computerized dynamic pupillometry indices mirrors the heart rate variability parameters.

OBJECTIVE: Dynamic pupillometry (DP) is a simple, non-invasive computerized assessment of pupillary light response which provides data concerning both branches of the autonomous nervous system (ANS). Heart rate variability (HRV) analysis assess cardiac health and the ANS modulation on the heart. In this study, we aimed to evaluate the utility of DP as a predictor of cardiac autonomic activity assessed by HRV. PATIENTS AND METHODS: A total of 44 consecutive healthy subjects (mean age = 35.9 ± 7.4 years, 24 males) were enrolled. Pupil diameters (R0, R1, R2 and R%): latency (Lc), amplitude (Ac), velocity (Vc) and duration of pupil contraction (Tc): latency (Ld), velocity (Vd) and duration of pupil dilatation (Td) were measured in DP. Time and frequency domain indices of HRV were obtained from 24-h ambulatory electrocardiographic monitoring. RESULTS: There were strong significant correlations of Vc with LF/HF (r = -0.672, p = 0.001) and a measure of HRV: RMSDD (r = 0.654, p = 0.001). R% significantly correlated with PNN50 (r = -0.432, p = 0.003) and RMSDD (r = -0.422, p = 0.004) and LF/HF (r = 0.340, p = 0.024). Vc (ß = 0.647, p = 0.011) and Ac (ß = 0.320, p = 0.013) were found as independent predictors of RMSSD. Vc (ß = 0.578, p = 0.036) was found to be only significant predictor of PNN50. Vc (ß = -0.617, p = 0.008) and R% (ß = 0.309, p = 0.038) were found to be significant predictors of LF/HF. CONCLUSIONS: Pupillary autonomic functions assessed by DP correlates with cardiac autonomic functions evaluated by HRV. Among the DP parameters analyzed, Vc was a predictor of parasympathetic indices, and R% was a predictor of sympathetic indicators of cardiac autonomic functions.

Assessment of the relationship between dynamic pupillometry and exercise heart rate recovery among healthy subjects.

OBJECTIVE: Dynamic pupillometry (DP) is a simple, non-invasive computerized technique for assessment of pupillary light response which provides data concerning the balance of both branches of the autonomous nervous system (ANS). Heart rate (HR) recovery (HRR) after graded exercise reflects cardiac autonomic activity and predicts cardiovascular events. In this study, we aimed to evaluate the utility of DP as a predictor of cardiac autonomic activity assessed by HRR. PATIENTS AND METHODS: A total of 62 consecutive healthy subjects (mean age = 33.7 ± 8.6 years, 39 males and 23 females) were enrolled. Pupil diameters (R0, R1, R2 and R%): latency (Lc), amplitude (Ac), velocity (Vc) and duration of pupil contraction (Tc): latency (Ld), velocity (Vd) and duration of pupil dilatation (Td) were measured in DP. HRR indices were calculated by subtracting 1st (HRR1), 2nd (HRR2) and 3rd (HRR3) minute HR from the maximal HR during treadmill exercise stress test. RESULTS: HRR1 was 32.9 ± 8.0 bpm, HRR2 was 55.1 ± 11.6 bpm and HRR3 was 58.3 ± 12.7 bpm, respectively. Correlation analysis revealed significant positive correlations of HRR1 with Vc (r = 0.660, p = 0.001), Ac (r = 0.559, p = 0.001) and Vd (r = 0.412, p = 0.001). HRR had significant negative correlations with Lc (r = -0.442, p = 0.001), R% (r = -0.384, p = 0.002) and Ld (r = -0.286, p = 0.025). Vc [ß = 3.995 (1.040 to 6.951, 95% CI, p = 0.009)] and Lc [ß = -0.032 (-0.056 to -0.008, 95% CI, p = 0.01)] were found to be significant independent predictors of HRR1. CONCLUSIONS: Pupillary autonomic functions assessed by DP correlates with cardiac autonomic functions evaluated by HRR. Among the DP parameters analyzed, Vc and Lc were independent predictors of cardiac autonomic functions.