TY - JOUR
T1 - Continuous positive airway pressure treatment improves baroreflex control of heart rate during sleep in severe obstructive sleep apnea syndrome
AU - Bonsignore, Maria R.
AU - Parati, Gianfranco
AU - Insalaco, Giuseppe
AU - Marrone, Oreste
AU - Castiglioni, Paolo
AU - Romano, Salvatore
AU - Di Rienzo, Marco
AU - Mancia, Giuseppe
AU - Bonsignore, Giovanni
PY - 2002/8/1
Y1 - 2002/8/1
N2 - The role of the arterial baroreflex in the cardiovascular changes associated with the obstructive sleep apnea syndrome (OSAS), and the effect of nasal continuous positive airway pressure (CPAP) treatment on baroreflex function during sleep are unknown. Baroreflex control of heart rate was studied in 29 normotensive patients with OSAS under no treatment, in 11 age-matched control subjects, and in 10 patients at CPAP withdrawal after 5.5 ± 3.7 (range 3-14) months of treatment. Baroreflex control of heart rate was assessed by "sequence method" analysis of continuous blood pressure recordings (Finapres) obtained during nocturnal polysomnography. In untreated OSAS, baroreflex sensitivity (BRS) was low during wakefulness and non-rapid eye movement (REM) stage 2 sleep compared with control subjects, and correlated inversely with mean lowest SaO2 and the blood pressure increase after apneas. After CPAP treatment, the apnea-hypopnea index was lower, and mean lowest SaO2 higher than before treatment. After CPAP, patients were more bradycardic, blood pressure and its standard deviation decreased as SaO2 improved in non-REM stage 2 sleep, and BRS increased (nocturnal wakefulness: +59%; non-REM stage 2 sleep: +68% over pretreatment values). Our data suggest that baroreflex dysfunction in OSAS may be at least partly accounted for by nocturnal intermittent hypoxemia, and can be reversed by long-term CPAP treatment.
AB - The role of the arterial baroreflex in the cardiovascular changes associated with the obstructive sleep apnea syndrome (OSAS), and the effect of nasal continuous positive airway pressure (CPAP) treatment on baroreflex function during sleep are unknown. Baroreflex control of heart rate was studied in 29 normotensive patients with OSAS under no treatment, in 11 age-matched control subjects, and in 10 patients at CPAP withdrawal after 5.5 ± 3.7 (range 3-14) months of treatment. Baroreflex control of heart rate was assessed by "sequence method" analysis of continuous blood pressure recordings (Finapres) obtained during nocturnal polysomnography. In untreated OSAS, baroreflex sensitivity (BRS) was low during wakefulness and non-rapid eye movement (REM) stage 2 sleep compared with control subjects, and correlated inversely with mean lowest SaO2 and the blood pressure increase after apneas. After CPAP treatment, the apnea-hypopnea index was lower, and mean lowest SaO2 higher than before treatment. After CPAP, patients were more bradycardic, blood pressure and its standard deviation decreased as SaO2 improved in non-REM stage 2 sleep, and BRS increased (nocturnal wakefulness: +59%; non-REM stage 2 sleep: +68% over pretreatment values). Our data suggest that baroreflex dysfunction in OSAS may be at least partly accounted for by nocturnal intermittent hypoxemia, and can be reversed by long-term CPAP treatment.
KW - Autonomic nervous system
KW - Hypertension
KW - Sleep-disordered breathing
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U2 - 10.1164/rccm.2107117
DO - 10.1164/rccm.2107117
M3 - Article
C2 - 12153958
AN - SCOPUS:0036683376
VL - 166
SP - 279
EP - 286
JO - American Journal of Respiratory and Critical Care Medicine
JF - American Journal of Respiratory and Critical Care Medicine
SN - 1073-449X
IS - 3
ER -