Augmented Resting Beat-to-Beat Blood Pressure Variability in Young, Healthy, Hispanic Men

Hispanic Americans (HA) are at a higher risk for metabolic syndrome and diabetes compared to other racial groups in the United States, conditions that are well established risk factors for cardiovascular disease progression. Beat-to-beat blood pressure variability (BPV) is a known predictor of cardiovascular risk. However, racial differences in beat-to-beat BPV between HA and non-Hispanic white (WH) men have not been investigated. Therefore, we tested the hypothesis that young, healthy, HA men have greater resting beat-to-beat BPV compared to healthy age and body mass index matched WH men. We studied 8 young healthy HA men (23 ± 3 years, 24.2 ± 2.3 kg/m 2 , mean ± standard deviation) and 10 young healthy WH men (22 ± 3 years, P = 0.574; 24.1 ± 3.1 kg/m 2 , P = 0.948). During ten minutes of quiet supine rest, beat-to-beat arterial blood pressure (BP; finger photoplethysmography) was continuously recorded and brachial automated sphygmomanometry was used to verify beat-to-beat BP measurements (Welch Allyn). Stroke volume (SV) was estimated using the Modelflow method, then cardiac output (CO = SV x Heart rate) and total peripheral resistance (TPR = MAP / CO) were calculated. Standard deviation (SD), range, coefficient of variation (CV), and average real variability (ARV) were calculated for systolic (SBP), diastolic (DBP), mean arterial BP (MAP), CO and TPR. Resting SBP (HA: 116 ± 7 mmHg; WH: 118 ± 6 mmHg; P = 0.509), DBP (HA: 67 ± 4 mmHg; WH: 65 ± 5 mmHg; P = 0.432), and MAP (HA: 83 ± 4 mmHg; WH: 83 ± 5 mmHg; P = 0.830), were not different between groups. Beat-to-beat MAP SD (HA: 5.3 ± 1.3 mmHg; WH: 3.6 ± 0.9 mmHg; P = 0.004), range (HA: 30 ± 6 mmHg; WH: 20 ± 4 mmHg; P = 0.001), CV (HA: 6.4 ± 1.3 %; WH: 4.4 ± 1.1 %; P = 0.002), and ARV (HA: 1.4 ± 0.3; WH: 1.1 ± 0.3; P = 0.033) were all higher in HA men compared to WH men. Likewise, all SBP and DBP beat-to-beat variability measures were higher in HA men compared to WH men (all p < 0.05). HA men also had higher TPR SD (HA: 1.3 ± 0.2 mmHg/min/L; WH: 0.9 ± 0.2 mmHg/min/L; P = 0.009) and range (HA: 9 ± 2 mmHg/min/L; WH: 6 ± 2 mmHg; P = 0.009) compared to WH men, however there were no differences in any CO variability measures (P > 0.05). Despite normal resting BP, these preliminary data suggest that beat-to-beat BPV is higher in HA men compared to WH men, which was accompanied by an augmented TPR variability. This heightened BP and TPR variability in HA men warrants additional investigation. This work was supported by the College of Nursing and Health Innovation. This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.