P123: Reservoir Pressure is Independently associated with 11–12 Year Old’s Kidney Function: Population-Derived Study

Introduction Reservoir pressure (RP) and excess pressure (XSP) independently predict cardiovascular events in adults, but have never been investigated as markers of cardiovascular risk among children. This study aimed to determine the association of RP and XSP with end-organ makers of cardiovascular risk related to kidney function and large artery pre-atherosclerosis. Methods Participants were 1874 11–12 year-old children (50% male) from the Longitudinal Study of Australian Children’s Child Health CheckPoint study. Brachial blood pressure was measured by cuff oscillometric device (SphygmoCor XCEL, AtCor, Sydney). The same device was used to derive reservoir pressure (RP) and excess pressure (XSP) from the brachial pressure waveform. Kidney function was determined from estimated glomerular filtration rate (eGFR, n = 926) and large artery pre-atherosclerosis was determined from carotid intima media thickness (cIMT, n = 1131) using ultrasound. Results The eGFR was significantly correlated with RP peak (r = −0.109, p = 0.001), RP integral (r = −0.136, p < 0.001), XSP peak (r = 0.096, p = 0.004) and XSP integral (r = 0.102, p = 0.002). The RP (whether expressed as peak or integral) was significantly associated with eGFR after adjusting for sex, waist-to-hip ratio, heart rate and brachial BP indices (RP peak β = −0.079, p = 0.02, partial R 2 = 0.006 and RP integral β = −0.079, p = 0.02, partial R 2 = 0.007). XSP was not independently associated with eGFR after adjusting for the above variables. Neither RP nor XSP were significantly associated with cIMT. Conclusion Independent of conventional risk factors, RP was significantly associated with kidney function among a large population of Australian children. The non-invasive method to derive RP using an oscillometric cuff device could provide useful clinical information in children.