Objective To explore the risk factors for nocturnal hypoxemia in patients with ob-structive sleep apnea(OSA)and construct an assessment model.Methods A total of 303 patients with OSA diagnosed by polysomnography(PSG)were selected as research objects.Based on PSG re-sults,they were divided into case group(171 patients with hypoxemia)and control group(132 pa-tients without hypoxemia).Materials were compared between the two groups;multivariable Logistic re-gression analysis was used to screen risk factors for nocturnal hypoxemia in OSA patients and construct a risk assessment model.Value of the model was evaluated by the area under the curve(AUC)of the receiver operating characteristic(ROC)curve and K-fold cross-validation.Results The case group had significantly higher values in age,body mass index(BMI),neck circumference,proportion of smokers,hemoglobin,red cell distribution width(RDW),apnea-hypopnea index(AHI),the longest apnea duration(LAD),snoring index,and percentage of apnea-hypopnea duration to total sleep time(AHT％)when compared to the control group(P＜0.05).Logistic regression analysis showed that high BMI,high RDW,long LAD,and high AHT％were risk factors for nocturnal hypoxemia in OSA patients(P＜0.05).AUC value(0.952)of the ROC curve of the assessment model constructed based on these factors was higher than the AUC values of BMI(0.833),RDW(0.780),LAD(0.866),and AHT％(0.898)alone.One hundred times of 10-fold cross-validation demonstrated that the assessment model had good generalization ability.Conclusion Nocturnal hypoxemia in OSA patients is associated with high BMI,high RDW,long LAD,and high AHT％.The model constructed based on these factors plays an important role in evaluating nocturnal hypoxemia in OSA patients.

Objective To evaluate the application of fractional exhaled nitric oxide (FeNO) in the reducing treatment of bronchial asthma.Methods From October 2015 to September 2016,60 asthmatic patients with FeNO＞25 ppb were randomized into FeNO group and control group with 30 cases in each group.Patients in both groups were treated with combined inhaled corticosteroids and long-acting beta 2 agonist (ICS/LABA) starting with low doses;the dosage was adjusted according to the symptom control alone in control group,while in FeNO group the dosage was adjusted according to the symptom control and FeNO level.After 1 year-follow up,the Asthma Control Test (ACT) scores,Asthma Life Questionnaire (mini AQLQ)scores,pulmonary function,FeNO levels,blood eosinophil counts,total IgE,hierarchical control level,cumulative corticosteroid use and cumulative months of leukotriene receptor antagonists (LTRA) use were compared before and after treatment within group,and between two groups.Stratified analysis was carried out in the patients complicated with allergic rhinitis.Results After treatment,ACT scores,mini AQLQ scores and FEV1/pred (％) were significantly higher than those before treatmentin both groups (t=10.755,10.189,8.632 and 13.311,8.102,12.456,respectively,all P＜0.05),while the FeNO,EOS and total IgE levels were significantly lower than those before treatment (t=8.005,3.313,3.924 and 8.967,3.885,3.270,respectively,all P＜0.05),and the numbers of patients with good control were significantly increased (Z=-5.035 and-4.976 respectively,P＜0.05).Compared with control group,FeNO level was lower,mini AQLQ scores of symptom scores and emotional scores were higher and the average numbers of asthma attacks per patient per year were less after treatment in FeNO group (t=2.912,4.214,4.589,U=2.154,all P＜0.05).However,there was no significant difference in cumulative corticosteroid use and cumulative months of LTRA use between two groups (U=564.000 t=1.921 and 0.165,respectively,P＞0.05).For patients complicated with allergic rhinitis,the numbers of acute asthma attack were increased and the cumulative dosage of systemic corticosteroid use was higher in control group than those in FeNO group (both P＜0.05).Conclusion The reducing treatment strategy based on FeNO level and symptom control is of clinical value for patients with bronchial asthma,especially for those complicated with allergic rhinitis.