Association of level of cognition with sympathovagal imbalance and cardiovascular risks in prehypertension
Background and Aim: Prehypertension is more prevalent in young age group. In India, the prevalence of prehypertension varies from 24.5% to 27.2%. In midlife, blood pressure levels of prehypertension range may have an influence on memory. However, the degree of cognitive decline and its mechanisms in prehypertension is lacking. The aim of the present work is to study the association of the level of cognition with sympathovagal imbalance (SVI) and cardiovascular (CV) risks in prehypertension. Methods: Eighty‑four participants (42 normotensives and 42 prehypertensives) aged between 18 and 44 years were included in this case–control study. The demographic, anthropometric, basal CV parameters, heart rate variability, cardiovascular autonomic function tests (CAFTs), rate pressure product (RPP) as the indicator of CV risk, and event‑related potential P300 as the marker of cognitive function, and biochemical parameters of insulin resistance (IR), inflammation, and oxidative stress were recorded. Association of level of cognition with various factors was assessed by Pearson’s correlation analysis. Results: The basal CV parameters were significantly elevated, and total power was reduced in prehypertensives. In CAFTs, 30:15 ratio and Δ DBPIHG were increased, and E: I ratio was decreased in prehypertensive group. The latency of P300 was not significantly prolonged in prehypertensives. Although the correlation was not significant between P300 latency and low frequency: high frequency ratio (the marker of SVI), it was significant with RPP in prehypertensives. The fasting blood glucose, insulin, and homeostatic model assessment‑IR were not significant, and high‑sensitivity C‑reactive protein was elevated; oxidant status was increased and antioxidant status was decreased in prehypertensive groups. Conclusion: Although prehypertensives have SVI and increased CV risks, considerable memory impairment was not found in them. However, the level of cognition was linked to CV risks.