Postprandial glucose excursions is the main cause of elevated glycated hemoglobin levels in patients with diabetes mellitus. Controlling postprandial glucose is also an important strategy for preventing and treating chronic complications of diabetes.

To evaluate the effect of protein preload meal pattern on postprandial glucose excursions in patients with type 1 diabetes mellitus (T1DM) .

This study is a randomized, open-label, within-subject crossover clinical registration study. We selected thirty-one T1DM patients aged 18-45 years with a course of disease >1 year who were admitted to the First People's Hospital of Yunnan Province from February 2019 to December 2021. After ten hours fasting, all patients ate two isocaloric test meals with the same ingredients, one is protein preload meals and another is mixed meals, on the 4th and 7th days of wearing continuous glucose monitoring systems (CGM), respectively. CGM was used to analyze the CGMS data 5 hours after a meal, including peak postprandial glucose, time to peak postprandial glucose, average blood glucose level; area under curve (AUC) for blood glucose, incremental area under curve (iAUC) for blood glucose, mean amplitude of glycemic excursions (MAGE), the incremental glucose peak (?Peak) and low (?Low), and the proportion of time of hypoglycemia and hyperglycemia events. We also used a generalized linear mixed model to compare the difference in blood glucose excursions during five hours post-prandial.

Twenty-six T1DM patients were included in the statistical analysis. There was no significant difference in fasting blood glucose, peak blood glucose, mean blood glucose from 0 to 300 min, mean blood glucose from 180 to 300 min, the proportion of time when blood glucose>10 mmol/L (%), the proportion of time when blood glucose>13.9 mmol/L (%), MAGE, and ?Peak between protein preload meals and mixed meals (P>0.05). The peak time and ?Low of the protein preload meals were higher than those of the mixed meals, and the mean blood glucose (0-180 min) of the protein preload meals was lower than that of the mixed meals (P<0.05). No hypoglycemia event occurred in the mixed meals group. iAUC_0-30, iAUC_0-60, iAUC_0-90, iAUC_0-120, iAUC_0-150, iAUC_0-180, and iAUC_0-210 of protein preload meals were lower than those of mixed meals (P<0.05). The blood glucose excursion at 0-30 min, 31-60 min, and 181-210 min of protein preload meals were significantly lower than those of mixed meals (P<0.05) .

This study showed that protein preload meal pattern can improve postprandial glucose levels and reduce postprandial glucose variability in adults with T1DM.