Correlation between Pre-Ramadan HbA1c Levels and Fasting Outcomes in Individuals with Type 2 Diabetes: Evidence from the Global 2020–2022 DAR Survey

Abstract Glycemic control prior to Ramadan is considered an essential determinant of fasting safety in individuals with diabetes. While the International Diabetes Federation-Diabetes and Ramadan Alliance risk calculator incorporates glycated hemoglobin (HbA1c) into fasting risk stratification, there is limited evidence to validate the cutoffs of < 7.5% and > 9% for predicting fasting outcomes. This study evaluates the association between pre-Ramadan HbA1c categories and key fasting-related outcomes in a large multinational cohort of individuals with diabetes. This subanalysis of the Diabetes and Ramadan (DaR) Global Survey categorized participants from 7 global regions covering more than 20 countries into three groups based on pre-Ramadan HbA1c: < 7.5%, 7.5 to 9%, and > 9%. Outcomes included fasting participation, hypoglycemia, hyperglycemia, and fasting interruptions due to glycemic events. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for participants with HbA1c > 9% compared to those with HbA1c < 7.5%. Of 11,717 participants, 37.7% had HbA1c < 7.5%, 33.8% had 7.5 to 9%, and 28.5% had > 9%. Fasting participation was highest in the < 7.5% group (89.3%) and lowest in the > 9% group (80.5%; OR 0.49, 95% CI 0.43–0.56). Compared to < 7.5%, HbA1c > 9% was associated with increased odds of hyperglycemia (OR 5.10), breaking the fast due to hyperglycemia (OR 5.63) and severe hyperglycemia (OR 8.11), daytime hypoglycemia (OR 1.48), and hypoglycemia-related fasting interruption (OR 1.77). Severe hypoglycemia rates did not differ significantly between HbA1c groups. Higher pre-Ramadan HbA1c was associated with lower fasting participation and a greater risk of hyperglycemia and hypoglycemia-related complications. These results support the use of the current HbA1c thresholds in Ramadan risk assessment and emphasize the importance of optimizing glycemic control and providing targeted education before Ramadan.