Plasma Concentration Of Carbon Monoxide In Patients With OSAS Complicating Hypertension

Objective: To study the plasma concentration of endogenous carbon monoxide (CO) in patients and explore the changes of CO in patients with OSAS complicating Hypertension. Methods: Polysomnography(PSG) and 24 hours ambulatory blood pressure monitoring (ABPM) were performed in 186 patients with OSAS and/or complicating Hypertension. All the research objects were selected from out-patiant clinic and hospitalization within 2006-2007. According to the diagnostic code of OSAS and hypertension, patients were divided into four groups, OSAS with hypertension group(120 patients) ,simple hypertension group (36 patients ) ,simple OSAS group(30 patients) and healthy controls (20 patients ). Polysomnography (PSG) adopts 44 canals monitoring produced by compumedics company. 24 hours ABPM adopts Spacelabe90217 ambulatory blood pressure monitoring. Plasma concentration of CO was detected by the method introduced by Chalmers. All the research object deplete severe anaemia, polycyth emia, patients who use Erythropoiesis Stimulating Factor; deplete severe heart disease, brain disease, kidney disease and liver disease; deplete thyrolid gland disfunction, diabetes mellitus and secondary hypertension. Results: (l)OSAS patients' abdomen circumference and neck collar are obviously larger than those of control group's, no matter whether complicating hypertension. At the same time, with the higher of apnea-hypopnea index (AHI), OSAS patiants' abdomen circumference and neck collar are increasing, correlation analysis indicates that AHI has positive correlation with body mass index, abdomen circumference and neck collar. Time of oxygen saturation <90% (TSaO2<90%) has positive correlation with age, body mass index and abdomen circumference. The minimum oxygen saturation (minSaO₂) has negative correlation with age, body mass index, abdomen circumference and neck collar. [2] Plasma CO levels in OSAS complicating hypertension group and simple OSAS group were significantly higher than control group(p<0.05). Correlation analysis showed that Plasma CO level has positive correlation with AHI(r=0.206,p=0.029). Factor analysis showed the reciprocation effect AB is P>0.05. Factor analysis showed OSAS and hypertension have no reciprocation effect (P>0.05). The main effect of factor A is P<0.05. OSAS can increase Plasma CO level. The main effect of factor B is P>0.05,there has no statistically significant. The research suggests that hypertension has no influence on plasm CO level. Through gradual regressive analysis, the minimum saturation of blood oxygen at night is the very variance which leads in regression equation of OSAHS patients' plasm CO level. [3]dDBP and nDBP in moderate OSAS group no matter whether complicating hypertension are lower than those of mild and severe OSAS group(p<0.05). Conclusion:(1) The age, body mass index, neck collar and abdomen circumference were correlated with the degree of OSAS patients. The dependability of neck collar and abdomen circumference were better than body mass index. (2) OSAS can increase the level of endogenous CO. Hyoxemia is the cause which induce OSAS patients synthetize CO. [3]Endogenous CO as a guard factor may participate the form of OSAS patients' BP.