2005 Heightened sympathetic activity in obstructive sleep apnoea syndrome and its relationship to cardiovascular disease
Dr. Chung-yan Chan, Department of Medicine, North District Hospital
Background and methods
Patients with obstructive sleep apnea syndrome (OSAS) were found to have high sympathetic activity. The effect of short-term nasal continuous positive airway pressure (nCPAP) on sympathetic activity among OSAS patients was evaluated in this study.
Results
Twenty-four hour urine catecholamine excretion in 26 newly diagnosed OSAS patient was measured before and after treatment with nCPAP for at least one month period. The results of 21 patients who completed two sets of 24-hour urine catecholamine measurements were analyzed. There was significant reduction in 24-hour urine nor-epinephrine excretion after nCPAP therapy, mean urine nor-adrenaline reduced from 376.9 to 285.0nmol/day, with a mean reduction of 91.86nmol/dL (SD 194.86, 95% CI 3.15 – 180.55, p = 0.043)
Conclusion
nCPAP therapy could effectively reduce sympathetic activity in patients with moderate to severe OSAS. The effect of nCPAP was evident even after a short period of treatment.
