P105 Endocrine, autonomic and vascular function in children with Sleep Disordered Breathing

Abstract SDB is a risk factor for cardiovascular disease and co-exists with chronic endocrine disorders such as type II diabetes and metabolic syndrome. Children with SDB have increased blood flow velocity, an indicator of reduced vascular compliance and early vascular aging. Increased blood flow velocity is positively associated with sympathetic activity, increased arterial sympathetic nerve fibre density and endothelial damage. Whether changes in endocrine function occur concomitantly with altered autonomic and vascular function in children with SDB was assessed. Thirty six children scheduled for tonsillectomy underwent overnight polysomnography (SDB severity), pupil light reflex (autonomic function), fasting brachial artery blood flow assessment (vascular function - Doppler Ultrasound). Leptin and Ghrelin - both hormonal markers associated with sympathetic activity were measured in urine using ELISA and serum using MagPlex. The following dimensions of the dorsal lingual artery (tonsil) were measured – medial thickness, medial area, smooth muscle cell number/layers. We observed a positive correlation between serum and urine leptin and ghrelin concentrations. Increased blood flow velocity and arterial medial thickness were both associated with increased serum and urine leptin and ghrelin concentrations. Pupil light reflex was negatively associated with serum leptin and ghrelin levels. OAHI was positively correlated with leptin and ghrelin concentration (urine and serum) but not blood flow velocity. Blood flow velocity was inversely correlated with SpO2 nadir (REM). Our findings suggest that SDB has a global effect on the autonomic, vascular and endocrine systems.The impact of untreated paediatric SDB on the development of comorbidities in later life needs urgent attention.

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O006 Early vascular ageing in children with sleep disordered breathing: evidence of vascular hypertrophy and hyperplasia

SLEEP Advances ◽

10.1093/sleepadvances/zpab014.005 ◽

2021 ◽

Vol 2 (Supplement_1) ◽

pp. A3-A4

Author(s):

P Vokolos ◽

D Kennedy ◽

K Lushington ◽

J Martin ◽

D Wabnitz ◽

...

Keyword(s):

Blood Flow ◽

Flow Velocity ◽

Blood Flow Velocity ◽

Vascular Function ◽

Arterial Wall ◽

Velocity Time Integral ◽

Sympathetic Overactivity ◽

Time Integral ◽

Vascular Ageing ◽

Increased Blood Flow

Abstract Children with sleep disordered breathing (SDB) have evidence of increased blood flow velocity and sympathetic overactivity. Sympathetic overactivity leads to peripheral vasoconstriction, increased vascular resistance and consequently, increases blood flow velocity. Early vascular ageing involves premature arterial thickening and stiffening that leads to changes in vascular function. Both increased blood flow velocity and sympathetic overactivity are promoters of arterial remodelling and hence, early vascular ageing. No studies have directly histologically investigated arterial wall structure in children with SDB and how it relates to vascular function. Thirty-six children scheduled for tonsillectomy underwent polysomnography to determine SDB severity and resting brachial artery blood flow velocity (velocity time integral and peak systolic velocity) using Doppler ultrasound. The dorsal lingual artery (tonsil) was stained using hematoxylin and eosin techniques to examine arterial wall structures. Increased velocity time integral correlated with increased arterial medial thickness (r = 0.50, P<0.01), arterial smooth muscle cells (r =0.43, P<0.05) and arterial smooth muscle layers (r=0.45, P<0.01). These relationships remained significant after controlling for body-mass index (BMI). Increased BMI was associated with increased velocity time integral (r=0.61, P<0.01), arterial medial thickness (r=0.37, P<0.05) and arterial medial area (r=0.36, P<0.05). SpO2nadir (TST/REM) was inversely associated with arterial medial area (r=-0.35; r=-0.38, P<0.05). These results demonstrate that increased blood flow velocity is associated with changes in arterial wall composition in children with SDB. This suggests that paediatric SDB, a treatable disorder, is potentially a modifiable risk factor for early vascular ageing and resultant cardiovascular disease in adulthood.

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