Study On Relationship Of ANP And BNP With Nocturnal Polyuria In Patients With Obstructive Sleep Apnea Syndrome

Objectives: To assess the relation between nocturnal secretion of atrial natriuretic peptide (ANP) , brain natriuretic peptide (BNP) and nocturnal polyuria in patients with obstructive sleep apnea syndrome (OSAS).Methods: 10 cases with nocturnal polyuria and co-existing moderate-to-severe OSAS were selected as trial group, 10 cases without nocturnal polyuria and SAS as control group. Plasma levels of BNP and ANP in all subjects were measured at 10PM and at 6AM and the nocturia output, the osmotic pressure of nocturia and the nocturia excretion of Na~+ were surveyed in polysomnography (PSG) monitoring night. After the trial group received nasal continuous positive airway pressure (nCPAP) treatment, all the criteria were repeated.Results :(1) In trial group, plasma ANP levels increased from (568±41) ng/L(10PM)to (1017±148)ng/L(6AM) (P<0.001) in PSG monitoring night, after treatment with nCPAP,it decreased to (584±58) ng/L (P<0.001) .In control group, plasma ANP levels at 6AM( (553±58) ng/L) when compared to at 10PM ( (540±60) ng/L) had no significant increase (P>0.05 ) .(2) In trial group, plasma BNP levels had no significant change from 10PM((57±16)ng/L) to 6AM ((60±19)ng/L) (P>0.05) in PSG monitoring night, after treatment with nCPAP,it was (60±19)ng/L ,which had no significant decrease than before treatment. In control group, plasma BNP levels had no significant change from 10PM ( (50±9) ng/L) to 6AM( (51±10) ng/L) (P>0.05) .(3) After treatment with nCPAP, the reduction of ANP was correlated with the reduction of the AHI, the reduction of the nocturia output, the reduction of the nocturia excretion of Na~+ and the addition of the osmotic pressure of nocturia.The correlation coefficients were 0.736, 0.836, 0.891, 0.841,respectively(all P<0.05).The reduction of BNP had no significant correlation with the above parameters.Conclusion: Nocturnal polyuria in patients with obstructive sleep apnea syndrome is probably correlated with the increase of nocturnal ANP, and it is not correlated with BNP.