[Efficacy of continuous positive airway pressure therapy upon resistant hypertension in patients with obstructive sleep apnea hypopnea syndrome].
OBJECTIVE
To investigate the efficacy and possible mechanism of continuous positive airway pressure (CPAP) therapy upon blood pressure in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and resistant hypertension (RH).


METHODS
Thirteen OSAHS patients with RH were recruited. Before and after 3-month CPAP therapy, their blood pressures at 10:00 PM, 2:00 AM and 6:00 AM were measured and their morning plasma concentrations of aldosterone (ALD) and plasma renin activity (PRA) tested at supine position with radioimmunoassay.


RESULTS
Compared with blood pressure parameters at pre-CPAP therapy, there was a significant decrease in blood pressure before sleep at the end of 3-month CPAP therapy [(135.5 +/- 2.8)/(84.2 +/- 4.6) vs (152.2 +/- 19.2)/(98.9 +/- 15.6) mm Hg, P < 0.01], at night during sleep [ (133.1 +/- 2.4)/(81.5 +/- 4.6) vs (156.6 +/- 19.4)/(102.8 +/- 16.6) mm Hg, P < 0.01] and in the early morning [(151.5 +/- 3.0)/(81.2 +/- 3.2) vs (172.1 +/- 23.7)/(98.1 +/- 6.5) mm Hg, P < 0.01]. Comparison of plasma concentrations of ALD and PRA before and after 3-month CPAP therapy indicated that there was a significant difference in ALD [(538 +/- 42) vs (408 +/- 53) pmol/L, P < 0.01] but not significantly different in PRA [(0.27 +/- 0.14) microg x L(-1) x h(-1) vs (0.20 +/- 0.12), P = 0.221].


CONCLUSIONS
CPAP therapy could significantly improve RH and plasma ALD concentration. Elevated plasma ALD concentration is possibly involved in the pathogenesis of RH in OSAHS patients.
Zhang
Xi-Long
XL
Department of Respiratory Medicine, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China. zhangxilong1952@yahoo.com.cn
Li
Yan-Qun
YQ
D000328:Adult; D045422:Continuous Positive Airway Pressure; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010845:Obesity Hypoventilation Syndrome / Q000150:complications / Q000628:therapy; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000628:therapy*