Tianjin Medical Journal ›› 2025, Vol. 53 ›› Issue (3): 252-256.doi: 10.11958/20241962

• Clinical Research • Previous Articles     Next Articles

Effects of seasonal and temperature variations on fasting blood glucose levels in patients with type 2 diabetes mellitus

LIANG Tongtong1(), CAO Li2, LI Jun1, YU Yan1,3, YAN Yujie4, XU Huilin1,()   

  1. 1 Minhang Center for Disease Control and Prevention, Shanghai 201101, China
    2 Zhoupu Hospital Affiliated to Shanghai University of Medicine and Health Sciences
    3 School of Public Health, Fudan University
    4 Xinhong Community Health Service Center of Minhang District
  • Received:2024-11-28 Revised:2025-01-08 Published:2025-03-15 Online:2025-03-31
  • Contact: E-mail:iamxuhuilin@163.com

Abstract:

Objective To explore the impact of seasonal and temperature variations on fasting blood glucose (FPG) in patients with type 2 diabetes (T2DM). Methods A retrospective analysis was conducted on clinical data of 31 994 T2DM patients managed by community health service center in Minhang District, Shanghai, from January 1, 2020 to October 31, 2023. The effect of seasonal and temperature variations on FPG levels and blood glucose control was investigated in T2DM patients. Results A total of 72 334 FPG tests were conducted in 31 994 T2DM patients, with an average of 2.26 tests per person. The number of tests conducted in spring, summer, autumn and winter were 15 558, 34 018, 21 929 and 829, respectively. The FPG levels of T2DM patients were lower in summer and autumn compared to those of winter and spring (P < 0.05), while the FPG control rates were higher in summer and autumn compared to those of winter and spring (Bonferroni-corrected, P < 0.008). There were no significant differences in FPG levels and blood glucose control rates between spring and winter, or between summer and autumn. The results of the multilevel mixed-effect Logistic model analysis with FPG control status as the dependent variable revealed that the risk of uncontrolled FPG in T2DM patients during winter and spring was 47% (aOR=1.465, 95%CI: 1.156-1.855) and 51% (aOR=1.510, 95%CI: 1.384-1.645), respectively, which was higher than that of autumn. The levels of FPG and the incidence of FPG abnormalities reached peak in February and reached the trough in September. Both the FPG levels and the incidence of FPG abnormal exhibited a trend of increasing with the decrease of temperature, and with a lag effect observed. Spearman rank correlation test indicated that there was a negative correlation between FPG levels and incidence of abnormal FPG and the monthly average daily temperature one month lagged (rs=-0.951, P<0.001 and rs=-0.944, P<0.001). Conclusion FPG levels of T2DM patients exhibit a pronounced seasonal pattern of elevation during winter and spring, accompanied by a reduction in blood glucose control rates. FPG levels and the prevalence of abnormal FPG exhibit a negative correlation with the monthly average daily temperature, and there is a lag effect.

Key words: diabetes mellitus, type 2, fasting plasma glucose, glycemic control, season, temperature

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