Pulse Rate Variability and All-Cause Mortality Risk in the General Japanese Population.

Background: Although pulse rate variability (PRV) is considered a potential surrogate marker for heart rate variability in the assessment of autonomic function, it is not clear whether PRV-derived parameters predict mortality risk in the general population. Methods and Results: Between 2009 and 2018, a total of 5,943 Japanese individuals, aged 30-79 years, were recruited for a prospective study and followed until the end of 2022. The pulse wave was examined over a 5-min period using a fingertip photoplethysmography sensor to determine the resting heart rate (RHR) and the time and frequency domains of PRV. A Cox proportional hazard model was used to calculate the hazard ratio (HR) and 95% confidence interval (CI) of PRV-derived parameters for all-cause mortality using the penalized cubic splines method. During 12.4 years of follow up, 437 deaths were recorded. The HR for mortality, adjusted for sex, age, and community, for the lowest quartiles of the standard deviation of the normal-to-normal intervals (SDNN) increased 1.51 times (95% CI 1.15-1.98) vs. the third quartile. Although mortality risk was attenuated after adjustment for several confounders and RHR, PRV-derived parameters of autonomic function showed significant non-linearity of association with mortality risk in the spline analysis. Conclusions: Low values of PRV-derived autonomic parameters were associated with an increased risk of all-cause mortality in the general Japanese population.