OBJECTIVE: Continuous Positive Airway Pressure (CPAP) is the most effective therapy for symptomatic obstructive sleep apnoea (OSA). However, uncertainty remains about the effectiveness of CPAP in improving OSA-related metabolic dysregulation. This meta-analysis of randomized controlled trials (RCTs) aimed to investigate whether CPAP, compared to other control treatments, could improve glucose or lipid metabolism in OSA patients.
METHODS: Relevant articles were searched in three different databases (MEDLINE, EMBASE and Web of Science) from inception to 6th Feb 2022 through specific search terms and selection criteria.
RESULTS: From a total of 5553 articles, 31 RCTs were included. CPAP modestly improved insulin sensitivity as determined by mean fasting plasma insulin and Homeostasis Model Assessment of Insulin Resistance reduction of 1.33mU/L and 0.287, respectively. In subgroup analyses pre-diabetic/type 2 diabetic patients as well as those with sleepy OSA showed a greater response to CPAP. Regarding lipid metabolism, CPAP was associated with a mean total cholesterol reduction of 0.064mmol/L. In subgroup analyses, the benefit was higher in patients that showed more severe OSA and oxygen desaturations at the baseline sleep study as well as in younger and obese subjects. Neither glycated haemoglobin nor triglycerides, HDL- and LDL-cholesterol were reduced by CPAP.
CONCLUSIONS: CPAP treatment may improve insulin sensitivity and total cholesterol levels in OSA patients but with low effect size. Our results suggest that CPAP does not substantially improve metabolic derangements in an unselected OSA population, but the effect may be higher in specific subgroups of OSA patients.

UNASSIGNED: In recent years, mesenchymal cellular therapies have received much attention in the treatment of diabetes. In this meta-analysis, we aimed to evaluate the efficacy of mesenchymal stem cell therapy in type 2 diabetes mellitus patients.
METHODS: A comprehensive literature search was carried out using PubMed, Scopus, Web of Science and Central databases. A total of 1,721 articles were identified, from which nine full-text clinical trials were qualified to enter the current meta-analysis. The assessment groups included patients with type 2 diabetes, and levels of C-peptide, glycosylated hemoglobin and insulin dose were analyzed before and after mesenchymal stem cell infusion. Data analysis was carried out in Stata version 11, and the Jadad Score Scale was applied for quality assessment.
RESULTS: Changes in levels of C-peptide after mesenchymal stem cell therapy were: standardized mean difference 0.20, 95% confidence interval -0.61 to 1.00, glycosylated hemoglobin levels were: standardized mean difference -1.45, 95% confidence interval -2.10 to -0.79 and insulin dose were: standardized mean difference -1.40, 95% confidence interval -2.88 to 0.09.
CONCLUSIONS: This meta-analysis of prospective studies showed associations between mesenchymal stem cell therapy and control of glucose level in patients with type 2 diabetes.

Diabetes is a chronic condition; those with diabetes are at high risk of developing diabetes complications. One important approach to tackle the diabetes burden is to screen for undiagnosed diabetes and to identify factors that lead to the risk of developing diabetes in the future. The earlier identification of individuals at risk of developing diabetes is crucial for delaying or preventing the onset of type 2 diabetes. Numerous studies have demonstrated that circulating concentrations of branch chain amino acids (BCAAs) predict the risk for developing diabetes; thus, contributing to the recent resurgence of interest in these common analytes. The present review aimed to address the recent findings regarding BCAAs and their role in insulin resistance and diabetes. Recent studies demonstrate that BCAAs are strongly associated with a number of pathological mechanisms causing insulin resistance and type 2 diabetes. The research findings related to BCAA signaling pathways and metabolism broaden our understanding of this topic. However, it remains unclear how increased levels of BCAAs will assist in the prediction of future insulin resistance or type 2 diabetes. Future research needs to determine whether BCAAs are a causative factor for insulin resistance and type 2 diabetes, or just a biomarker of impaired insulin action.