Plasma adhesion molecules in children with sleep-disordered breathing.

STUDY OBJECTIVES

To determine whether childhood sleep-disordered breathing (SDB) is associated with elevated levels of plasma adhesion molecules.

DESIGN

Prospective, observational study.

SETTING

Sleep Medicine Center of Kosair Children's Hospital.

PARTICIPANTS

Thirty-nine children with SDB (apnea-hypopnea index [AHI] > 5/h), 47 children with mild SDB (AHI 1 to 5/h), and 42 healthy control subjects (AHI < 1/h).

MEASUREMENTS AND RESULTS

One hundred twenty-eight children underwent a standard polysomnographic assessment with a blood draw the following morning. Plasma levels of CRP and the adhesion molecules intercellular adhesion molecule (ICAM)-1 and P-selectin were measured. No differences were observed in ICAM-1 levels among the groups; however, obese children had higher ICAM-1 levels than nonobese children (425.0 +/- 123.0 ng/mL vs 375.6 +/- 107.1 ng/mL, p = 0.04) [mean +/- SD]. P-selectin levels were significantly higher in the SDB group (84.0 +/- 52.2 ng/mL) and the mild SDB group (89.3 +/- 49.9 ng/mL) when compared to control subjects (49.5 +/- 22.3 ng/mL; p < 0.001 for both groups). Furthermore, P-selectin correlated with AHI (r = 0.32, p < 0.001), respiratory arousal index (r = 0.27, p = 0.002), and nadir of oxygen saturation as measured by pulse oximetry (r = - 0.19, p = 0.038). Plasma CRP levels were found to correlate with P-selectin even after controlling for BMI (r = 0.20, p = 0.05). No correlations were found between CRP and ICAM-1.

CONCLUSIONS

Children with SDB have plasma elevations of P-selectin, a marker of platelet activation, lending support to the premise that inflammatory processes are elicited by SDB in children, and may contribute to accelerated risk for cardiovascular morbidity. In contrast, elevations in ICAM-1 are primarily associated with obesity rather than SDB.