Fasting during Ramadan is associated with changes in activity and blood glucose excursion in people with type 2 diabetes on three or more anti-hyperglycemic agents PROFAST-3.

Background: The physiological changes during Ramadan in people with type 2 diabetes (T2D) are not well described in the literature. However, advances in technology have created new frontiers to understand these changes. This study aims to understand the impact of Ramadan fasting on blood glucose excursion, vital signs, and physical activities in people with T2D who are on three or more antidiabetic medications.

Methods: This prospective observational study was conducted at Hamad General Hospital, National Diabetes Centre, between February 1, 2020 and May 30, 2020 (covering three months before and including the month of Ramadan). We included people with T2D who were on three or more antidiabetic medications. Medications were adjusted during Ramadan based on international guidelines. Flash glucose monitoring and Fitbit devices were used to monitor glucose levels and physical activity. The primary outcomes were changes in time in range (TIR), time above range (TAR), and time below range (TBR) before and during Ramadan.

Results: We included 18 patients with T2D, of whom 13 were males (72.2%). The mean age was 51.2 years (SD 7.4), the mean HBA1c was 7.8% (SD 1.0), and the mean duration of T2D was 12.5 years (SD 3.1). There were no significant changes in TIR, TAR, and TBR before and after Ramadan. There was no statistically significant difference in the TIR, TAR, and TBR during fasting hours and after iftar. However, the ambulatory glucose profile shows a reduction in glucose levels during fasting hours, reaching a nadir just before iftar, followed by a prolonged period of hyperglycemia post iftar. Physical activity levels decreased during fasting hours but increased approximately one hour before iftar. Multilinear regression analysis showed a positive correlation between engaging in vigorous physical activity and the TBR during fasting hours [β-coefficient (95% CI): 0.26 (0.07-0.45), p < 0.05].

Conclusion: Our findings show no significant changes in the overall glucose profile, except for prolonged post-iftar hyperglycemia. Intensive physical activity during fasting hours can increase the risk of hypoglycemia. This studyhighlights the need for further in-depth research to better understand the impact of lifestyle changes on blood glucose excursion during Ramadan.