Heart rate and blood pressure control in infants exposed to maternal cigarette smoking.
OBJECTIVE
Exposure to maternal cigarette smoking is a major risk factor for sudden infant death syndrome (SIDS). Foetal and postnatal smoke-exposure may alter cardiovascular control in infants. We studied heart rate (HR) and blood pressure (BP) responses in smoke-exposed infants.


METHODS
Eleven infants exposed to maternal cigarette smoking were studied at the age of 12 +/- 2.1 (range 10-16) weeks. Twenty healthy, age-matched infants from non-smoking families served as controls. During confirmed slow-wave sleep (NREM3), 3-5 sec side motion and 45 sec 45 degrees head-up tilt tests were performed.


RESULTS
Control infants showed consistent biphasic HR and BP responses to side motion, with an initial 2-5% increase followed by a 2% decrease (p < 0.0001). In smoke-exposed infants, the initial HR (p = 0.009) and BP responses (p < 0.0001) were markedly reduced, and the subsequent decrease in BP was more prominent (systolic blood pressure, SBP, p = 0.005; diastolic blood pressure, DBP, p = 0.03). No differences were observed between the groups in tilt test results, HR variability or HR responses to spontaneous arousals.


CONCLUSIONS
Maternal cigarette smoking may alter vestibulo-mediated cardiovascular control in early infancy. This may contribute to increased SIDS risk.
Viskari-Lähdeoja
S
S
Hospital for Children and Adolescents, Helsinki, Finland.
Hytinantti
T
T
Andersson
S
S
Kirjavainen
T
T
D001143:Arousal; D001794:Blood Pressure; D016022:Case-Control Studies; D005260:Female; D006339:Heart Rate; D006801:Humans; D007223:Infant; D008297:Male; D008425:Maternal Behavior; D018811:Maternal Exposure / Q000009:adverse effects*; D011247:Pregnancy; D012307:Risk Factors; D012890:Sleep; D012907:Smoking / Q000009:adverse effects*; D013398:Sudden Infant Death / Q000209:etiology; D014724:Vestibular Function Tests