41

Background. Clinical practice guidelines (CPGs) are commonly used tools in the management of chronic conditions such as type 2 diabetes (T2D). In line with the principles of evidence-based medicine (EBM), CPGs should be based on systematic reviews and meta-analyses of randomized controlled trials (RCTs). This study evaluates the extent to which CPGs on glycemic control in type 2 diabetes draw on existing meta-analyses of randomized controlled trials to justify their recommendations, and whether they use the GRADE approach for quality assessment. Methods. Building on a previous study assessing the quality of CPGs (Tudrej et al. 2020), an additional study was conducted, including guidelines published between January 2015 and May 2021. Meta-analyses were selected from a systematic review by Rodriguez et al., which focused on the benefits and risks of intensive glycemic control. CPGs were categorized as “EBM-compliant” if they cited or included meta-analyses covering clinically relevant, patient-centered outcomes: total mortality, macrovascular and microvascular complications, and symptomatic hypoglycemia. Use of the GRADE approach was also examined. Results. Of the 28 CPGs analyzed, only 14% (4/28) were “EBM-compliant,” citing relevant meta-analyses to support their recommendations. Two-thirds (67%) of CPGs did not cite any of the 10 key meta-analyses. GRADE was used by 21% (6/28) of CPGs, of which only 2 were also “EBM-compliant.” Discussion. The majority of CPGs did not incorporate high-level evidence from meta-analyses of RCTs, raising concerns about the rigor and transparency of these guidelines. The lack of systematic integration of evidence could affect the quality of clinical decisions, suggesting a need for improved methodology in the development of CPGs related to glycemic control in type 2 diabetes. Conclusion. This study reveals significant gaps in the evidence base for CPGs on type 2 diabetes, highlighting the need for better adherence to EBM principles and the systematic use of robust meta-analyses in guideline development.