Non-dipping blood pressure variations in adult Kazakhs are derived from decreased daytime physical activity and increased nighttime sympathetic activity

AbstractMany of the elderly Kazakhs have been found to exhibit non-dipping blood pressure variations (BPV). Such variations are seen in both normotensive and hypertensive Kazakhs. The purpose of this study was (1) to determine whether middle–aged Kazakhs also include large numbers of non-dippers, (2) to compare the characteristics of non-dipping and dipping, and (3) to clarify the mechanisms responsible for non-dipping type BPV by examining the autonomic nervous activity and physical activity. We performed ambulatory blood pressure (BP) monitoring. The subjects were divided into two groups (dipping and non-dipping type). We monitored the subjects’ physical activity with accelerometry and assessed their autonomic nerve activity by performing a frequency domain analysis of their heart rate variability (HRV). The power spectral density (PSD) of the HRV was calculated using fast Fourier transformation. We analyzed the systolic blood pressure (SBP) variations with the maximum entropy method (MEM). The dippers ...