Analysis of deceleration capacity in healthy females

AIM To analyze the deceleration capacity (DC) in healthy females and to explore the effects of age and circadian rhythm on DC. METHODS We collected the average heart rate (HR), DC and time domain parameters of heart rate variability (HRV) (SDNN, RMSSD) for 24 h, both day- (15:00-20:00) and night- (00:00-05:00) time, respectively, from 24-h Holter recordings in 339 healthy females aged 18 to 70 years. According to age, subjects were divided into four groups, young (18-30 years), middle-age (31-44 years), perimenopausal (45-55 years) and older group (56-70 years). RESULTS DC, HRV and HR generally decreased with age. DC and RMSSD were significantly higher at night in all age groups. DC showed a significant correlation with HR, SDNN and RMSSD. CONCLUSION DC declines with age and shows regular changes following circadian rhythm. Moreover, DC is closely correlated with HRV.