ESPE Abstracts

Background: Activation of the renin-angiotensin-aldosterone system, hyperinsulinemia, and hyperleptinemia have been implicated in the pathogenesis of obesity-related arterial hypertension (AH). We therefore studied serum renin, aldosterone, leptin, and insulin levels in overweight and obese children with and without AH.

Methods: 129 (77 male) overweight/obese (BMI z-score > 1.3 / > 2), children and adolescents, seeking obesity management were studied. Fasting insulin, leptin, renin, and aldosterone were measured by automated methods, and office blood pressure readings were done by oscillometric method. AH was defined by the ESH 2016 guidelines. P25 and P75 limits for sex and age were used to define decreased/ increased renin or aldosterone levels.

Results: Median (range) age was 12.1 (6.6 – 17.3) years, while median BMI z-score was 2.29 (1.30-3.29). An elevated systolic (S) and diastolic (D) blood pressure (BP) was registered in 52 (40 %) and 16 (12 %) subjects, respectively. AH (increased SBP and/or DBP) was more prevalent in male vs. female (51 % vs 33 %; P = 0.024) and obese vs. overweight subjects (41 % vs 25 % ; P = 0.026). Increased renin and aldosterone levels were measured in 4 (3 %) and 82 (63 %) subjects, while 84 (65%) subjects had decreased renin levels. 48 of the 84 (57%) subjects with low renin levels had elevated aldosterone levels. Renin levels correlated positively with aldosterone levels (Rho = 0.42; P < 0.000). However, plasma renin nor aldosterone correlated significantly with serum leptin, serum insulin, age, or z-scores of BMI, waist circumference, SBP, or DBP. Increased renin and aldosterone levels were seen in 3 (1 %) and 44 (59 %) of the 74 normotensive and 1 (1 %) and 38 (69 %) of the 55 hypertensive subjects, while 51/74 (69 %) normotensive and 33/55 (60 %) hypertensive subjects had decreased renin levels. Hypertensive subjects had similar median renin, aldosterone, and leptin levels but significantly (P < 0.001) higher median insulin levels (133(39-467) vs 194(38-93) pmol/L).

Conclusion: AH was observed in 43 % of overweight/obese children. Low renin hypertension was diagnosed in 25.5 % and high renin hypertension in less than 1%. Our results confirm that male sex, higher adiposity (BMI z-score), and hyperinsulinemia are risk factors for obesity-related arterial hypertension.