Objectives:
To examine the association between incident sleep-disordered breathing (SDB) and blood pressure and blood pressure reactivity in a population based sample of adolescents.
Methods:
The Penn State Child Cohort is a general population based sample of 700 children aged 5-12 years at the baseline examination (2000-2005). Currently, 300 participants have completed their 8-year follow up examination. Blood pressure was assessed at follow up in the evening using an automated device prior to the sleep recording in three positions. Three assessments in the seated position were completed after 5 minutes of rest. This was followed by 3 assessments in the supine position after 5 minutes of rest. The averages of the 2
nd
and 3
rd
readings for both positions are reported. Finally the subject was asked to stand as fast as possible and 2 additional readings were completed immediately upon their foot hitting the floor. These two standing readings were averaged. The difference between standing and supine BP was used as measures of vascular reactivity. The age, gender and height adjusted mean level of BP measures comparing individuals with and without incident SDB (defined as Apnea Hypopnia Index, AHI>5/hr) after excluding individuals with baseline SDB were calculated.
Results:
We observed no significant differences in diastolic blood pressure across the three positions. However, systolic blood pressure across all three positions and vascular reactivity were significantly elevated in those with incident SDB, as summarized in Table 1.
Conclusion:
In an 8-year followup of this population based sample of children, there was no persistence of SDB from baseline. Incident SDB (about 11%) was significantly associated with elevated systolic BP across all three positions. Further, SDB was associated with increased systolic BP reactivity, which has been associated with increased risk of CVD and the development of hypertension in adults.
Risk factors associated with habitual snoring and sleep-disordered breathing in a multi-ethnic Asian population: a population-based study
