Effects Of Continuous Positive Airway Pressure In Patients With Obstructive Sleep Apnea Syndrome And Type2Diabetes Mellitus: A Systematic Review And Meta-analysis

Objectives: Obstructive sleep apnea syndrome (OSAS) is a common disorder inthe adult population. Glucose dysregulation is often observed in OSAS patients anddiabetic patients suffer more frequently than healthy subjects. These two disorders isreported to have interactive influence. Continuous positive airway pressure (CPAP) isstate of art treatment for OSAS, that may also be helpful to the glucose metabolism inpatients with diabetes, therefore, a meta-analysis of randomized control trials wereconducted to evaluate the effectiveness of CPAP on blood glucose control in patientswith type2diabetes mellitus and OSAS.压气(C)治疗选荟萃分析的Methods: We searched the PubMed, EMBASE, and Chinese Journal of VIP andCNKI database. From database establishment until March2013for published studies onthe relationship between OSAS and type2diabetes studies, randomized control trials(RCTs) on the metabolic effectiveness of continuous positive airway pressure in patientswith type2diabetes. Inclusion criteria were:(1) Literature with completed datapublished in English and Chinese;(2) Studies in adults patients with type2diabetes andOSAS with no race, gender preference;(3) Randomized control trials (RCTs) withoutregard to the allocation concealment or blinding method;(4) Interventions: CPAPtherapy as treatment group and non-specific treatment as control group;(5) Evaluation:glycosylated hemoglobin(HbA1c), fasting blood glucose (FBG), postprandial bloodglucose(PBG), insulin resistance (HOMA-IR),BMI, and other metabolic indicators.Respiratory indicators such as apnea hyperpnoea index (AHI), lowest oxygen saturation(LSPO2), Epworth sleepiness score (ESS) were also included. Exclusion criteria: articlespublished just as abstracts, non-RCTs, repetition of publication, unpublished, andincomplete data. A preliminary screening was conducted, and retrieved literature withthe titles, and two independent reviewers according to inclusion and excluding criteria for qualified publications reviewed abstracts. Data were extracted with a unified formGoogle and other searching engines were used to find relevant literature on the Internet.For those that lack needed data, the corresponding authors were contacted through email.The information collected was the author’s name, year of publication, research area andthe study population, the measure of intervention, basic characteristics of the twogroups of patients, study duration and effect index, etc. For literature published inEnglish, the mean and standard deviation of HbA1c, BMI, ESS, was collected as theeffect indicators. For literature in Chinese, the merger mean and standard deviation ofHbA1c, FBG, PBG, HOMA-IR, BMI, ESS, AHI, LSPO2,was extracted as the effectindicators. JADAD Scale was used to evaluate the quality of included studies. ReviewManager5.1software was used for meta-analysis. The results of data reported in Englishand in Chinese were shown separately.Results:586articles were found,8RCTs involving330OSAS and type2diabetespatients were retrieved after excluding those of51repeat publication,118published inabstracts and in meeting,19not conformed to the exclusion criteria,76of incompletedata,297of none RCTs. Seventeen epidemiological surveys were included in thesystematic review. Meta-analysis of studies published in English suggested that CPAPimproved ESS[WMD=-6.33,95%CI:(-9.01,-3.66), P<0.00001], but not HbA1c[WMD=-0.12,95%CI:(-0.86,0.62), P=0.75], BMI[WMD=-0.62,95%CI:(-2.40,1.16),P=0.49]. Meta-analysis of the five studies published in Chinese showed that CPAPtherapy improved HbA1c[WMD=-0.50,95%CI:(-0.72,-0.28), P<0.00001], FBG[WMD=-1.19,95%CI:(-1.52,-0.87), P<0.00001], PBG[WMD=-1.02,95%CI:(-1.43,-0.62), P<0.00001], but there were no effects on HOMA-IR[WMD=-1.80,95%CI:(-4.64,1.04), P=0.21]. BMI[WMD=-0.69,95%CI:(-1.79,0.41), P=0.22].CPAPtherapy improved LSPO2[WMD=24.04,95%CI:(20.04,28.05), P<0.00001], but notAHI[WMD=-23.65,95%CI:(-51.24,3.93), P=0.09].Conclusion: CPAP therapy improves LSPO2, glycemic control for diabeticpatients with OSAS, but large-scale studies are needed.