The ratio between the heart period (T) and the time constant (τ), characterizing the arterial pressure decay during the diastole, is a known ventriculo-arterial coupling factor, which is constant in mammals. Previously we have shown T/τ can be determined using standard ambulatory blood pressure(BP) monitoring (ABPM) records and when increased ,predicts all-cause mortality. Here we evaluated the association between increased T/τ and risk-related variation in some continuous clinical and demographic characteristics. We analyzed ABPM records of 2823 hypertensive patients (age 56±16, 54% women, 58% medicated and 9% with diabetes). T/τ was determined using its model expression, as the ratio between T coefficient of variation (SD/mean) and ln(SBP/DBP) variability (SD), where SBP and DBP are the systolic and diastolic BP and T (in sec) is 60/heart rate (HR). One-way ANOVA was applied to T/τ (dependent variable) using as a factor one of the following characteristics after grouping at constant intervals: age [in 5-yr intervals], body mass index (BMI) [5 kg/m
2
], mean SBP, DBP and pulse pressure (PP) [5 mmHg]; the corresponding dipping [5%], and hear rate (HR) [5 bpm]. End groups with size<50 were eliminated. T, τ and T/τ were 0.88±0.13 sec, 1.18±0.48 sec and 0.88±0.42, respectively. T/τ was greater than 0.9, 1.0 and 1.1, respectively, for 37%, 29% and 16% of the patients (1048, 829 and 647 of 2823). T/τ variation with the tested factors was monotonous and highly significant (p<10
-6
for all). T/τ increased with older age, higher BMI, SBP, PP, and lower DBP, HR, and their dipping: T/τ was greater than 1.03 for age>77 yr; >1.06 for BMI>32 kg/m
2
; >1.06 for (mean) SBP>162 mmHg; >1.07 for DBP<68 mmHg; >1.07 for HR<57 beat/min; >1.05, >0.96 and >1.11 for SBP- DBP- and HR dipping smaller than 2.5%, 2.5% and 7.5%, respectively. The finding that T/τ values greater than a relatively narrow threshold (1.05±0.04) corresponds to risk factors level, and tendency tendency of the tested characteristics supports the view that T/τ that deviates from sucha threshold may signify autonomic cardiovascular dysregulation.