Postprandial hypotension is one of the serious problem in the management of elderly hypertension. The present study was designed to investigate possible difference in post prandial blood pressure falls between central and peripheral sites.Design and Method:
Apparently healthy participants in our physical checkup program (n = 360) were recruited and oral glucose (75g) tolerance test was performed. Brachial and central systolic blood pressures (SBPs) were assessed before and after glucose load. Brachial SBP (oscillometer) and radial artery pressure waveforms (tonometer) were recorded using an automated device, and central SBP was estimated using SBP corresponding to the second systolic peak of radial pressure waveforms (HEM-9000AI, Omron Healthcare, Kyoto).Results:
The mean age was 53.6 ± 8.2 years old and brachial and central systolic blood pressure was 127.9 ± 18.1 mmHg 118.9 ± 17.9 mmHg, respectively, at baseline. Oral glucose load significantly reduced both brachial (124.6 ± 16.4 mmHg, p < 0.001) and central SBPs (112.8 ± 16.8 mmHg, p < 0.001). However, reduction in BP after glucose load was greater in central (−6.2 ± 10.6 mmHg) than in brachial SBP (−3.4 ± 11.3 mmHg, p < 0.001), and blood pressure fall more than 20 mmHg was more frequently observed in central (n = 39, 10.8%) than in brachial SBP (n = 23, 6.4%; p < 0.05). The change in augmentation index after oral glucose load was an independent predictor of the difference in postprandial falls between brachial and central SBPs in multivariate analysis (p < 0.001).Conclusions:
Oral glucose load reduces both brachial and central SBPs, with greater reduction in central than in brachial SBP. Vascular relaxations caused after glucose load may have reduced the amplitude of the reflection wave. Postprandial blood pressure fall measured at brachium may underestimate the postprandial blood pressure fall in the brain.