The Association of Apolipoprotein A1 and B with Glycated Hemoglobin Among Adults in Saudi Arabia

Diabetes mellitus (DM) is one of the most prevalent chronic diseases worldwide, with a high burden in the Middle East, particularly in Saudi Arabia. Apolipoproteins, including apolipoprotein A1 (ApoA1) and apolipoprotein B (ApoB), play essential roles in lipid metabolism and cardiovascular disease, and have emerging associations with glycemic control. This retrospective cohort study investigated the relationship between ApoA1, ApoB, and glycated hemoglobin (HbA1c) levels in Saudi adults and examined the mediating role of body mass index (BMI) in these associations. HbA1c was measured by turbidimetric inhibition immunoassay (TINIA) on the Alinity c system, and ApoA1 and ApoB were assessed via an immunoturbidimetric assay using the Cobas c501 system. Data from 10,591 participants, collected between 2020 and 2023, were analyzed using statistical models adjusted for age, sex, and BMI. Structural equation modeling (SEM) was then employed to investigate potential mediating effects. The results demonstrated an inverse association between ApoA1 and HbA1c, whereas ApoB and the ApoB/A1 ratio showed positive correlations with HbA1c. Participants in the highest ApoA1 quartile exhibited significantly lower HbA1c levels compared to those in the lowest quartile, while those in the highest ApoB quartile had significantly higher HbA1c levels. BMI was found to mediate the ApoB-HbA1c relationship, indicating that adiposity may amplify the association between ApoB and glycemic dysregulation. This study highlights a novel metabolic link between apolipoproteins and glycemic control in a large Saudi cohort. The findings underscore the importance of integrated lipid and weight management in DM care and support further research to clarify underlying mechanisms.