The Comparison Of Winter And Summer Of Glycosylated Hemoglobin A1c Levels In Patients With Type 2 Diabetes Mellitus In Northeast China

Objective:To compare the winter and summer of HbA1c levels in patients with T2DM in Northeast China,and to analyze the possible related factors causing the winter and summer changes in patients with T2DM in Northeast China.Methods:A total of 841 patients with T2DM in the Second Hospital of Jilin University,who had stable condition,less than 5 years of disease,and long-term residence in Northeast China,were studied and they were hospitalized in 2015（December）,2016（January,February,March,July,August,September,October and December）,2017（January,February,March,July,August,September,October and December）or2018（January,February,March,July,August,September and October）respectively.The patients were categorized into two groups according to whether they were admitted to the hospital in the winter（December to March of the following year）or the summer（July to October）.We compared the differences of HbA1c levels between the two groups in T2DM patients,and comparative analyzed their general characteristics including gender,age,blood pressure,BMI,waist circumference and other relevant metabolic indicators including FPG,OGTT 2hPG,TG,TC,HDL-C,LDL-C,UA,FT₃,FT₄,TSH,FCP,1hCP,and 2hCP.Meanwhile,we analyzed the possible related factors causing the winter and summer changes of HbA1c levels in T2DM patients in Northeast China.Results:1.HbA1c levels in Northeast China were significantly higher in the winter than in the summer（P<0.05）;2.The levels of BMI,TC,FCP,FT₄,FPG and OGTT 2hPG in the winter were significantly higher than those in the summer（P<0.05）;3.The levels of UA and 2hCP in the winter were significantly higher than those in the summer（P<0.05）;4.Statistically significant univariate variables were adjusted by multivariate influencing factors to show that HbA1c was correlated with season,BMI,2hCP and OGTT 2hPG.Conclusions:1.The HbA1c levels of T2DM patients in Northeast China were affected by the season,and they were significantly higher in the winter than in the summer（P<0.05）;2.The levels of BMI,TC,UA,FCP,2hCP,FT₄,FPG and OGTT 2hPG of T2DM patients in Northeast China had differences in the winter and summer;3.Season,BMI,2hCP,and OGTT 2hPG were independent factors affecting HbA1c of T2DM patients in Northeast China;4.In clinical work,paying attention to the effect of seasons on HbA1c of T2DM patients in Northeast China,and effective intervention of possible related factors affecting HbA1c,is of great significance for T2DM patients in Northeast China to better control plasma glucose and reduce plasma glucose fluctuations.