Changes in plasma angiotensin II and circadian rhythm of blood pressure in hypertensive patients with sleep apnea syndrome before and after treatment / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To explore the changes in plasma angiotensin II (Ang II) and circadian rhythm of blood pressure among hypertensive patients with sleep apnea syndrome (SAS) before and after continuous positive airway pressure (CPAP) or surgical treatment.</p><p><b>METHODS</b>A total of 180 essential hypertension patients were enrolled in our study. The determination of plasma Ang II concentration, ambulatory blood pressure (ABP), and polysomnography (PSG) monitoring were performed before and 3 months after CPAP or surgical treatment.</p><p><b>RESULTS</b>Patients were classified into three groups by their apnea-hypopnea index (AHI): essential hypertension group (EH group, n = 72; AHI< 5), essential hypertension with mild SAS group (EH+mild SAS group, n = 60, 5 ≤ AHI < 20), and essential hypertension with moderate and severe SAS group (EH + moderate-severe SAS group, n = 48, AHI ≥ 20). The concentrations of plasma Ang2 in the above three groups were 13.42 ± 3.27, 16.17 ± 3.82, and 18.73 ± 4.05 ng/mL respectively before treatment, and Ang2 concentration in EH patients combined with SAS was significantly higher than that in EH group (all P < 0.05). After treatment the values in the latter two groups significantly decreased to 14.67 ± 2.56 and 15.03 ± 3.41 ng/mL respectively (P < 0.05). The incidence of non-dipper blood pressure curve in EH patients was 31.9%, and those in hypertensive patients with mild SAS and moderate-severe SAS were 51.7% and 58.3%, respectively before treatment. The incidence of non-dipper blood pressure curve in the EH patients with mild SAS was significantly higher than that of patients with EH alone (P < 0.05). After CPAP treatment or surgery, the incidence of non-dipper blood pressure curve in the two SAS groups was significantly decreased to 38.3% and 39.6%, respectively (P < 0.05).</p><p><b>CONCLUSIONS</b>Ang II might play a role in blood pressure variability in patients with obstructive SAS. CPAP or surgical treatment can improve blood pressure disorder and decrease plasma Ang II level in patients with obstructive SAS.</p>

Circadian blood pressure variability and plasma neopterin level before and after surgery for obstructive sleep apnea syndrome / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the change of circadian blood pressure variability (BPV) and plasma neopterin before and after surgery (uvulopalatopharyngoplasty) for patients with obstructive sleep apnea syndrome (OSAS).</p><p><b>METHODS</b>A total of 382 OSAS patients underwent uvulopalatopharyngoplasty were divided into three groups based on polysomnography (PSG) results: mild OSAS (n = 206), moderate OSAS (n = 108) and severe OSAS (n = 68). Plasma neopterin, 24-hour ambulatory blood pressure monitoring (ABPM), PSG were measured before and 3 months after surgery.</p><p><b>RESULTS</b>Plasma neopterin increased in proportion to severity of OSAS before surgery (15.08 nmol/L, 27.68 nmol/L and 37.32 nmol/L in patients with mild to severe OSAS) which were significantly reduced post surgery (9.92 ng/ml, 15.07 ng/ml and 18.54 ng/ml, all P < 0.05 vs. pre-surgery). The incidence of non-dipper curve in three OSAS groups were 50.2%, 72.7% and 86.5%, respectively before surgery and the values decreased to 34.8%, 48.2% and 49.2% after surgery (all P < 0.05 vs. pre-surgery). Relevance analysis indicates that D-value of nocturnal and diurnal blood pressure was negatively correlated with plasma neopterin.</p><p><b>CONCLUSION</b>Our findings indicated that plasma neopterin and the incidence of non-dipper could reliably reflect OSAS severity and could thus be used to evaluate the surgery efficacy. Plasma neopterin might be an important player in the pathophysiology of OSAS via modulating blood pressure variability.</p>