A 4-year prospective follow-up study of childhood OSA and its association with BP

• Published in: Chest Vol. 145; no. 6; p. 1255
• Main Authors: Li, Albert M, Au, Chun T, Ng, Crystal, Lam, Hugh S, Ho, Crover K W, Wing, Yun K
• Format: Journal Article
• Language: English
• Published: United States 01.06.2014
• Subjects: Adolescent; Blood Pressure - physiology; Blood Pressure Monitoring, Ambulatory; Child; Circadian Rhythm - physiology; Comorbidity; Female; Follow-Up Studies; Hong Kong; Humans; Hypertension - physiopathology; Longitudinal Studies; Male; Obesity - physiopathology; Polysomnography; Prospective Studies; Severity of Illness Index; Sleep Apnea, Obstructive - physiopathology; Hong Kong
• ISSN: 1931-3543
• DOI: 10.1378/chest.13-1333

Childhood OSA is a prevalent condition associated with raised BP as documented in cross-sectional studies. This study aimed to determine whether baseline or change in OSA severity was associated with ambulatory BP at 4-year follow-up. Children who participated in our previous OSA prevalence research were invited to undergo a repeat overnight sleep study and 24-h ambulatory BP monitoring in this 4-year follow-up study. BP parameters of subjects with differing baseline OSA severity, that is, obstructive apnea-hypopnea index (OAHI) < 1/h, 1 to 5/h, and > 5/h, were compared. Overweight and normal-weight children were analyzed separately. One hundred eighty-five of 306 subjects (60%) were included in the analysis, of whom 58 were overweight at baseline. Linear increasing trends of wake systolic BP (SBP), wake diastolic BP (DBP), and sleep SBP z scores at follow-up were found across groups of increasing baseline OSA severity in the normal weight but not in the overweight subgroup. After adjusting for BMI z score, baseline OAHI was independently associated with all BP z scores at follow-up but not associated with changes in BP z scores across 4 years. On the other hand, change in OAHI was independently associated with sleep SBP and DBP z scores at follow-up and with changes in sleep SBP and DBP z scores across 4 years. This study provides longitudinal data as additional proof that childhood OSA is associated with elevated BP independent of obesity.