Abstract P331: Higher Allostatic Load Score is Associated With Early Cardiovascular Risk in Young South Africans. The AfricanPREDICT Study

Abstract

Background: The Allostatic load score (ALS) is a composite score that measures the cumulative physiological burden of sustained exposure to stress and biological dysregulation. ALS has markers capture risk in 4 domains (neuro-endocrine, metabolic, cardiovascular, and immunological). Higher ALS in adults predict cardiovascular disease (CVD), but it is unknown whether ALS is associated with CVD risk in youth and young adults (YA), and whether the risk and association would differ at such an early age. Aims: In youth and YA we compared 1) the total ALS; 2) the cardiovascular profile according to high and low ALS; and 3) the association of ALS with markers of CVD. Methods: Participants in the African PRospective study on the Early Detection and Identification of Cardiovascular disease and HyperTension (AfricanPREDICT) were 587 youth<24years (48% Male, 21±2 years) and 579 YA≥24years (49% Male, 27±2 years) were evaluated. The ALS was calculated from fasting biomarkers using the upper quartile population distribution of dehydroepiandrosterone (DHEA), cortisol, interleukin-6 (IL-6), C-reactive protein (hsCRP), BMI, systolic-BP, diastolic-BP, and lower quartile of HDL-cholesterol. The upper quartile of ALS in the whole population was defined as high ALS. Retinal vessel analyses, pulse wave velocity, and echocardiography were obtained and associations with ALS determined by regression analyses adjusted for sex, ethnicity, cotinine, gamma-glutamyl-transferase (GGT) and physical activity. Results: ALS median range was 1-8, and a high ALS of >3 was observed in 35% of youth, and 47% YA. In youth with high ALS, ALS associated with narrower retinal arteries (Adj R 2 :0.16, β-coefficient, -1.73, (95%CI), -2.95, -0.94), P =0.052), greater pulse wave velocity (Adj R 2 :0.56, 0.75 (0.48, 1.98), P =0.021), increased left ventricular mass index (Adj R 2 :0.61, 2.21 (0.43, 8.46) P =0.048), lower left ventricular function (global longitudinal strain) (Adj R 2 :0.37, -0.45 (-1.06, -0.06) P =0.015). Similarly, in YA with high ALS, ALS associated with narrower retinal arteries (Adj R 2 :0.43, -4.54 (-6.58, -2.50), P <0.001), greater pulse wave velocity (Adj R 2 :0.44, 0.62 (0.09, 1.17), P =0.043), increased left ventricular mass index (Adj R 2 :0.53, 2.62 (1.52, 5.76) P =0.032), lower diastolic function (E/A ratio) (Adj R 2 :0.27, -0.11 (-0.18, -0.04) P =0.002). Conclusion: Youth and YA with high ALS had a more adverse CVD risk profile and greater association with markers of cardiovascular aging compared to their low ALS counterparts. ALS and allostatic dysregulation should be evaluated in youth and YA, when assessing current and future cardiovascular risk.