TY - JOUR
T1 - Daytime sympathetic hyperactivity in OSAS is related to excessive daytime sleepiness
AU - Donadio, Vincenzo
AU - Liguori, Rocco
AU - Vetrugno, Roberto
AU - Contin, Manuela
AU - Elam, Mikael
AU - Wallin, B. Gunnar
AU - Karlsson, Tomas
AU - Bugiardini, Enrico
AU - Baruzzi, Agostino
AU - Montagna, Pasquale
PY - 2007/8
Y1 - 2007/8
N2 - The aim of this study was to investigate the relationships among sympathetic hyperactivity, excessive daytime sleepiness (EDS) and hypertension in obstructive sleep apnoea syndrome (OSAS). Ten newly diagnosed OSAS patients with untreated EDS and daytime hypertension underwent polysomnography (PSG) and daytime measurements of plasma noradrenaline (NA), ambulatory blood pressure (BP), muscle sympathetic nerve activity (MSNA) by microneurography and objective assessment of EDS before and during 6 months of compliance-monitored continuous positive airway pressure (CPAP) treatment. One month after the start of CPAP, BP, MSNA and NA were significantly lowered, remaining lower than baseline also after 3 and 6 months of treatment. CPAP use caused a significant improvement of sleep structures, and reduced EDS. A statistical correlation analysis demonstrated that EDS was not correlated with sleep measures obtained from baseline PSG (% sleep stages, apnoea and arousal index, mean oxygen saturation value), whereas daytime sleepiness was significantly correlated with MSNA. Furthermore, MSNA and BP showed no correlation. Our data obtained from selected patients suggest that the mechanisms inducing EDS in OSAS are related to the degree of daytime sympathetic hyperactivity. Additionally, resting MSNA was unrelated to BP suggesting that factors other than adrenergic neural tone make a major contribution to OSAS-related hypertension. The results obtained in this pilot study need, however, to be confirmed in a larger study involving more patients.
AB - The aim of this study was to investigate the relationships among sympathetic hyperactivity, excessive daytime sleepiness (EDS) and hypertension in obstructive sleep apnoea syndrome (OSAS). Ten newly diagnosed OSAS patients with untreated EDS and daytime hypertension underwent polysomnography (PSG) and daytime measurements of plasma noradrenaline (NA), ambulatory blood pressure (BP), muscle sympathetic nerve activity (MSNA) by microneurography and objective assessment of EDS before and during 6 months of compliance-monitored continuous positive airway pressure (CPAP) treatment. One month after the start of CPAP, BP, MSNA and NA were significantly lowered, remaining lower than baseline also after 3 and 6 months of treatment. CPAP use caused a significant improvement of sleep structures, and reduced EDS. A statistical correlation analysis demonstrated that EDS was not correlated with sleep measures obtained from baseline PSG (% sleep stages, apnoea and arousal index, mean oxygen saturation value), whereas daytime sleepiness was significantly correlated with MSNA. Furthermore, MSNA and BP showed no correlation. Our data obtained from selected patients suggest that the mechanisms inducing EDS in OSAS are related to the degree of daytime sympathetic hyperactivity. Additionally, resting MSNA was unrelated to BP suggesting that factors other than adrenergic neural tone make a major contribution to OSAS-related hypertension. The results obtained in this pilot study need, however, to be confirmed in a larger study involving more patients.
KW - Continuous positive airway pressure
KW - Hypertension
KW - Muscle sympathetic nerve activity
KW - Obstructive sleep apnoea syndrome
KW - Sleepiness
UR - http://www.scopus.com/inward/record.url?scp=34548015836&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34548015836&partnerID=8YFLogxK
U2 - 10.1111/j.1365-2869.2007.00602.x
DO - 10.1111/j.1365-2869.2007.00602.x
M3 - Article
C2 - 17716282
AN - SCOPUS:34548015836
VL - 16
SP - 327
EP - 332
JO - Journal of Sleep Research
JF - Journal of Sleep Research
SN - 0962-1105
IS - 3
ER -