White coat hypertension in adolescents.

BACKGROUND: Although white coat hypertension (WCH) seems to occur in 20% or more of the adult hypertensive population, this clinical condition has rarely been described in adolescents. DESIGN: Routine use of ambulatory blood pressure monitoring (ABPM) procedure as part of the investigation of arterial hypertension in adolescents. METHODS: Office blood pressure was checked after 5 minutes of rest in the seated position by the auscultation method and ABPM was performed with oscillometrical equipment (SpaceLabs 90207, Redmond, Washington, USA). RESULTS: In the present study 6 adolescents (5 females, 3 white), suspected to suffer from arterial hypertension as judged by office blood pressure measurements, mean age 15.1 years (12.2 - 17.7), mean height 164.5 cm, mean weight 77.2 kg, mean body mass index 28.8 kg/m2 (25 - 35.2), were diagnosed with WCH using ambulatory blood pressure monitoring (ABPM). CONCLUSION: White coat hypertension should also be considered in the evaluation of arterial hypertension in adolescents.

Postexercise responses of muscle sympathetic nerve activity and blood flow to hyperinsulinemia in humans.

Although insulin and exercise cause dramatic changes in physiological parameters, the impact of exercise on neural and hemodynamic responses to insulin administration has not been described. In a study of the effects of a single bout of exercise on blood pressure (BP), muscle sympathetic nerve activity (MSNA), and forearm blood flow (FBF) responses to insulin infusion during the postexercise period, 11 healthy men underwent, in a random order, two hyperinsulinemic euglycemic clamps performed after 45 min of 1) bicycle exercise (50% peak O(2) uptake, Exercise session) and 2) seated rest (Control session). Data were analyzed during baseline and steady-state periods. Although insulin levels and insulin sensitivity were similar, baseline plasma glucose levels were significantly lower in the Exercise than in the Control session. Mean BP was significantly lower (3%) and FBF was higher (27%) in the Exercise session. Exercise increased insulin-induced MSNA enhancement (84%) without changing FBF and BP responses to hyperinsulinemia. In conclusion, a single bout of exercise that does not alter insulin sensitivity exacerbates insulin-induced increase in MSNA without changing FBF and BP responses to hyperinsulinemia.

[Ambulatory blood pressure monitoring in normal adolescents]. / Monitorização ambulatorial da pressão arterial em adolescentes normais.

PURPOSE: To evaluate technical aspects of ambulatory blood pressure monitoring (ABPM) in normal adolescents. METHODS: Forty five normal adolescents (27 female), 10-18 years old. RESULTS: ABPM recordings showed a mean of 90% successful readings; 30% of the patients complained of sleep disruption related to the functioning of the ABPM monitor; the mean systolic, diastolic and heart rate fall during sleep was 13%, 23% and 24% respectively; the mean systolic and diastolic blood pressure load, while awake, was in male adolescents 25.4 +/- 27.7% and 11.8 +/- 14.6%, and in female adolescents, 17.5 +/- 18.7% and 11.8 +/- 11.4%, respectively; the mean systolic and diastolic blood pressure load, while asleep, was in male adolescents 15.4 +/- 22.9% and 2.8 +/- 4.9% and, in female adolescents, 10.5 +/- 18.2% and 1.8 +/- 2.7%, respectively; the mean diastolic values of the first two hours of recording were higher than the ones obtained during the rest of the hours of recording while awake; different mean systolic, diastolic and heart rate values were found during the afternoon and nocturnal sleep periods. CONCLUSION: ABPM was well accepted by the adolescent population, with good technical results.