Association of carotid intima–media thickness and dyslipidaemia in patients with type 2 diabetes: a protocol for systematic review and meta-analysis

Abstract

Introduction Patients with diabetes mellitus (DM) often present with comorbidities such as hypertension, dyslipidaemia, insulin resistance, obesity and hyperglycaemia, which increases their risk of cardiovascular diseases (CVDs)-related mortality. Carotid intima–media thickness (CIMT), a biomarker for subclinical atherosclerosis, has been associated with overall CVD, especially in type 2 DM (T2DM). Hence, this protocol for systematic review and meta-analysis aims to review existing literature on the association of CIMT and dyslipidaemia in patients with T2DM.Methods and analysis The proposed systematic review and meta-analysis will be conducted according to an updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols guideline. A comprehensive search of peer-reviewed studies on Google Scholar, PubMed, Science Direct and Web of Sciences databases will be conducted up to 30 June 2023. A meta-analysis of data extracted from selected studies will be performed to explore the association between dyslipidaemia and CIMT in patients with diabetes. The effect estimates will be reported as standardised mean differences/Cohen’s d and 95% CIs. A random effect model will be used in case of high heterogeneity whereas fixed-effect model will be used in the absence of heterogeneity. All statistical analysis will be performed using SPSS V.29.0 software. In cases of high heterogeneity, subgroup analysis will be performed based on study design, countries of publication and body mass index to identify potential sources of heterogeneity. Publication bias will be assessed graphically via funnel plots and statistically using Egger’s regression test. Sensitivity analysis will also be performed to evaluate the stability of the overall effect size and the grading of recommendations assessment, development and evaluation will be used to grade the quality of analysed evidence.Ethics and dissemination As the proposed study will use secondary published data, approval will not be sought from the ethics committee.PROSPERO registration number CRD42023451731.