Masked hypertension is revealed by exaggerated submaximal exercise blood pressure among adolescents from the Avon longitudinal study of parents and children (ALSPAC)

Objectives: Masked hypertension (MH) is associated with hypertension-related markers of organ damage, but is undetectable by clinic (resting) BP. Exaggerated systolic BP response to submaximal exercise reveals MH in adults, but it is unknown whether this is the case during adolescence. We aimed to determine if exercise BP was raised in adolescents with MH, and associations with markers of organ damage. Methods: 585 adolescents (aged 17.7 ± 0.3 years; 41.9% male) from the Avon longitudinal study of parents and children (ALSPAC), completed a step-exercise test with post-exercise BP, resting (clinic) BP and 24-hour ambulatory BP (ABP). MH was defined on the basis of guideline adult thresholds as clinic BP ≤ 140/90 mmHg and 24 h ABP ≥ 130/80 mmHg, or paediatric thresholds (age, sex and height percentiles). Assessment of markers of organ damage including left-ventricular mass (LVM) and carotid-femoral pulse wave velocity (PWV) was also undertaken. Results: 45 (7.7%) participants were classified with MH. Resting and post-exercise SBP were higher in those with MH vs. normotensives (126.1 ± 7.3 mmHg vs. 114.7 ± 10.0 mmHg, p < 0.001; 152.2 ± 17.3 vs 141.1 ± 15.1 mmHg, p = 0.001). A post-exercise SBP threshold of 150 mmHg revealed MH (AUC = 0.69, 95% CI: 0.61–0.76, p < 0.001) and was associated with greater LVM index (30.2 ± 6.5 vs. 27.6 ± 5.8 g/m2.7, p < 0.001) and PWV (5.9 ± 0.6 vs. 5.7 ± 0.7 m/s, p = 0.01). Conclusions: This is the first study within adolescents demonstrating post-exercise SBP can reveal MH and an association with markers of organ damage. Exaggerated exercise BP might be a warning signal of underlying high BP and increased cardiovascular risk undetected by clinic BP.