O105 ISOLATED NOCTURNAL HYPERTENSION AND TARGET ORGAN INJURY IN YOUTH

Background and Objective: New American Heart Association (AHA) recommendations in 2022 for pediatric ambulatory blood pressure monitoring (ABPM) established static blood pressure (BP) cutoffs to define hypertension with an optimal sensitivity-specificity balance to best capture target organ injury (TOI). This increased the prevalence of ABPM hypertension, specifically isolated nocturnal hypertension. We utilized ABPM data from the SHIP-AHOY cohort to describe the epidemiology of INH in youth and to evaluate associations between INH and TOI. Methods: We defined INH as wake BP <130/80 mmHg and sleep BP >110/65 mmHg. INH was also evaluated by the 2014 AHA definition: wake BP <95th percentile with sleep BP >95th percentile. Primary outcome was left ventricular hypertrophy (LVH), defined as left ventricular mass index >38.6 g/m2.7. Cardiovascular risk factor (CVRF) scores described the number of risk factors for cardiovascular disease (dyslipidemia, obesity, hypertension by clinic systolic BP, insulin resistance) fro each participant. Logistic regression models assessed the association of INH with LVH, adjusted for age, sex, CVRF score, and ABPM tolerability. Results: Of 397 participants, 77 had INH, mostly (62%) due to elevated systolic BPs only. Median age and height were higher in INH than normotension (16.1 v 15.1 years, P=0.022) (height z-score 1.13 v 0.23, P=0.039). Other characteristics did not differ significantly between groups (Table 1). Estimated glomerular filtration rate was lower in INH. Among those with INH, 27% (N=19/71) had LVH, a greater proportion than found with 2014 definitions (21%, N=7/33). Children with INH had 2.61-fold adjusted odds of LVH compared to normotension (95%CI [1.20,5.69], P=0.016). Conclusions: Over 20% of the SHIP-AHOY cohort had INH, accounting for >1/3 of hypertension overall. INH was associated with older age and taller height, mostly due to systolic BP. Compared to 2014 guidelines, the 2022 definition of INH captured a higher prevalence of LVH. INH was independently associated with increased odds of LVH. Future studies should follow children with INH longitudinally for potential development of daytime hypertension. Table 1: Demographic, Anthropomorphic, and Clinical Characteristics of Isolated Nocturnal Hypertension vs Normotension