Impact of Microvascular Complications on Glycemic Outcomes in People with Type 2 Diabetes Observing Ramadan Fasting

Fasting during Ramadan may increase the risk of hypoglycemia and hyperglycemia in people with type 2 diabetes mellitus (T2D). This study investigated whether the presence of microvascular complications increases the risk of such events during Ramadan fasting. This cross-sectional analysis analyzed data on demographics, neuropathy, nephropathy, retinopathy, and fasting-related glycemic events from the 2020 and 2022 Diabetes and Ramadan Global Surveys of adults with T2D. Of 12,529 individuals, 10,707 (85.5%) fasted during Ramadan. Of those, 15.5% experienced hypoglycemia and 15.1% hyperglycemia, with 9.2 and 3.4% breaking their fast due to each, respectively, and 1.8 and 0.9% experienced severe hypo- and hyperglycemia requiring medical intervention, respectively. Having ≥1 microvascular complication more than doubled the odds of daytime hypoglycemia (odds ratio [OR] = 2.16–2.31, p ≤ 0.0001) and hyperglycemia (OR = 2.00–2.43; all p ≤ 0.0001). The odds of breaking the fast due to hypoglycemia (OR = 2.25, 2.84, and 3.13) or hyperglycemia (OR = 2.09, 2.71, and 3.46) increased progressively with the number of microvascular complications (all p ≤ 0.0001). The odds of severe hypoglycemia requiring medical intervention (OR = 1.47 with 1, 1.82 with 2, and 3.50 with three complications; p ≤ 0.05–0.0001) or severe hyperglycemia (OR = 2.94, 3.69, and 6.49, respectively; all p ≤ 0.0001) during Ramadan fasting also increased with the burden of microvascular complications. Neuropathy was consistently associated with increased odds of all outcomes (all p ≤ 0.0001) apart from severe hypoglycemia (p = 0.67). The presence and overall burden of microvascular complications increase the risk of adverse glycemic events during Ramadan fasting in people with T2D. Pre-Ramadan risk stratification should consider complication burden, especially neuropathy.