Impaired cerebral vasoreactivity in white coat hypertensive adolescents.

BACKGROUND AND
PURPOSE: Although its incidence is not high, adolescent hypertension may predict hypertension and increased cardiovascular risk in adulthood. Therefore, the aim of the present study was to assess whether cerebrovascular reactivity is altered in adolescent white coat and sustained hypertensive patients compared to healthy teenagers.
METHODS: Fifty-nine normotensive, 47 white coat hypertensive (WCH), and 73 sustained hypertensive (SH) adolescents were studied. WCH and SH were differentiated by ambulatory blood pressure monitoring. Cerebrovascular reactivity was assessed by transcranial Doppler breath-holding test and was expressed in percent (%) change to the resting cerebral blood flow velocity value.
RESULTS: The percent increase in middle cerebral artery mean blood flow velocity after 30 s of breath holding was lower in both WCH (5.3 ± 3.1%) and SH (9.5 ± 2.6%) groups indicating lower vasodilatory reactivity compared to healthy adolescents (12.1 ± 2.2%). Additionally, serum nitric oxide (NOx) concentrations were lower in both WCH (30.6 ± 11 μM) and SH (30.7 ± 22.4 μM) groups compared to controls (38.8 ± 7.6 μM).
CONCLUSIONS: Both white coat and sustained hypertension result in decreased vasodilatory reaction to CO(2) in adolescents, suggesting involvement of the cerebral arterioles. The present study underlines the importance of early recognition and proper treatment of adolescent hypertension in order to prevent long-term cardiovascular complications.