P3.11 ETHNIC DIFFERENCES IN ARTERIAL WAVEFORM MEASURES IN A LARGE SAMPLE OF ADULTS ENROLLED IN THE VITAMIN D ASSESSMENT (VIDA) STUDY

Few studies have examined whether central arterial wavTable:eform measures vary with ethnicity. We aimed to provide a more comprehensive examination of ethnic differences in several cardiovascular risk factors, which may reveal new ethnic variations. A cross-sectional (baseline) analysis of 5110 adults (2971 M, 2139 F; age range, 50–84 years) from multiple ethnic groups (European/Other, Maori, Pacific, South Asian) participating in a New Zealand clinical trial of the effect of vitamin D supplementation (the ViDA study) on cardiovascular disease events was carried out. Peripheral blood pressure was measured with an Omron T9P oscillometric device. Arterial pressure waveforms were derived from suprasystolic brachial measurement using a Pulsecor R6.5 device, which previously has been shown to yield central pressure measurements highly correlated with those from aortic catheterisation. These were decomposed into forward- and backward-travelling waves and reservoir wave analysis was applied to derive reservoir and excess pressures. Compared to European/Other participants, those in the other three ethnic groups had significantly higher peripheral augmentation index after adjustment for age, sex and BMI (Table). Other ethnic differences in arterial waveform parameters and morphologies will be reported, including those derived from reservoir wave analysis. In conclusion, arterial function varies across ethnic groups. Longitudinal analyses will be carried out after 4 years follow-up to determine if arterial waveform measures predict cardiovascular disease incidence. Funding: Health Research Council of New Zealand Measure Mean (SE)* European/Other (n=2959) Mean difference (SE)* from European/Other P-value# Maori (n=194) Pacific (n=254) South Asian (n=139) Brachial BP (mmHg) Systolic 139.5 (0.4) 2.9 (1.4) 2.4 (1.2) −2.1 (1.6) 0.019 Diastolic 76.9 (0.2) 2.0 (0.7) 0.7 (0.7) −1.5 (0.9) 0.009 Peripheral augmentation Index % 100.6 (0.9) 8.8 (2.9) 3.2 (2.7) 5.8 (3.4) 0.009 *Adjusted for age, sex and BMI; #P-value for variation across all 4 ethnic groups. Table:Preliminary data from the ViDA study.