Abstract 440: Gender Differences In Hemodynamic And Autonomic Reactivity During Mental And Physical Laboratory Stress Tests In Normal Subjects Of The “Oman Family Study”
Background: Exaggerated cardiovascular reactivity for blood pressure (BP) and heart rate (HR) to laboratory stress tests has been proposed as a predictor of cardiovascular disease.
Subjects and Methods: The study was conducted in normal subject; 262 males and 280 females (mean age 30 ± 9 years, BMI 23.5 ± 4 years), from five large and highly consanguineous homogeneous Arab families of OFS. Hemodynamic parameters: Heart rate (HR), systolic, diastolic, mean BP (mmHg), Stroke index (SI, SI (ml/beat/m2), cardiac index (CI,L/min/m2) ), total peripheral resistance index (TPRI, yne*s*/cm2)), left ventricular ejection time (LVET, ms) and cardiac contractility (IC, 1000/sec ) were computed from beat-to-beat BP, ECG and impedance cardiography (TFM, CNSystems). Autonomic parameters ( LF; sympathetic , HF; parasympathetic, normalized) and baroreceptor sensitivity (BRS, ms/mmHg) were computed using spectral analysis and the sequence method, respectively. Hemodynamic and autonomic eactivity were averaged after 3 minutes of the word conflict (Δ WCT) and the cold presser (Δ CPT) tests. Results were compared using the Student’s paired ‘t’ test. A P value of < 0.05 was considered as significant.
Results: Males had significantly higher or lower reactivity than females for ΔWCT HR( 9.3 ±7 vs. 6.8 ± 6.3), SBP (9.9 ± 11 vs. 7.5 ±6.) , DBP (7.9 ± 8 vs. 6.3± 6), MBP (9.4 ±9.5, (SI -1.9 ± 5.5 vs. - 0.8 ± 4.7) and BRS ( -7.5± 15.9 vs. -4 ±10.5) . In contrast ΔCPT in females evoked significantly higher HR (8.2 ± 8 vs. 5.1 ± 8), CI (0.19 ± 0.4 vs. 0.08 ±0.4) and LF (11.6 ± 16.vs. 5.8 ±15.9) but significantly lower LVET (-8.7 ±16.6 vs. -3.8 ±9) and , BRS ( -6 ± 13 vs.-3.4 ±14 )
Conclusion: In this genetically and environmentally homogeneous cohort of OFS we found significant gender differences in hemodynamic and autonomic responses during the WCT and CPT tests. This may indicate that biological mechanism and genetic factors may contribute to such differences and should be receive special emphasis in cardiovascular research.
Author Disclosures: M.O. Hassan: None. D.S. Jaju: None. R.A. Bayoumi: None. S. Al-Yahyaee: None. A.G. Comuzzie: None. S.V. Voruganti: None. S.A. Albarwani: None.
- © 2014 by American Heart Association, Inc.