Seasonal Variability in Metabolic Profiles Among Individuals With Type 2 Diabetes: A One-Year Retrospective Analysis
Öz
Objective: This study aimed to evaluate the seasonal variation in HbA1c levels among individuals with type 2 diabetes (T2D) and to examine the relationship between these fluctuations and lipid parameters. Materials and Methods: In this retrospective cross-sectional study, 823 adults with T2D who presented to an internal medicine outpatient clinic during 2024 were included. Between-season comparisons were performed using the Kruskal–Wallis test for non-normally distributed variables and one-way ANOVA for normally distributed variables. To determine whether the seasonal effect on HbA1c was independent of metabolic parameters, multivariable ANCOVA models were constructed. Results: HbA1c levels varied significantly across seasons (Kruskal–Wallis p < 0.05). The highest adjusted mean HbA1c occurred in winter (8.75%), whereas the lowest values were observed in summer (8.20%); the summer–winter contrast remained significant (p = 0.035). In the multivariable ANCOVA model, triglycerides were positively associated with HbA1c (β = 0.002; 95% CI: 0.001–0.003; p < 0.001), whereas HDL cholesterol showed an inverse association (β = –0.019; 95% CI: –0.031 to –0.007; p = 0.002). Notably, seasonal differences remained independently significant after adjusting for lipid parameters (overall seasonal effect p = 0.021). Conclusion: HbA1c levels showed a distinct seasonal pattern, improving during summer and worsening during winter in individuals with T2D. Independent associations of HbA1c with triglycerides and HDL cholesterol suggest that seasonal glycemic variation occurs in interplay with underlying metabolic features. These findings underscore the clinical relevance of incorporating seasonal factors into diabetes management strategies.
Anahtar Kelimeler
Type 2 diabetes, Hba1c, Seasonal variation, Lipid metabolism, Triglycerides, HDL-cholesterol
Destekleyen Kurum
Proje Numarası
Etik Beyan
Teşekkür
Kaynakça
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