A comparative study of serum levels of glucose and aggression: A cross-sectional study

Diabetes mellitus is a metabolic disorder associated not only with physical complications but also with psychological and behavioral disturbances. Emerging evidence suggests that blood glucose fluctuations may influence mood, impulse control, and aggressive behavior. This prospective, observational study included 278 adult patients (171 with type 2 diabetes and 107 without diabetes) admitted to the Internal Medicine Outpatient Clinic of Istanbul Training and Research Hospital between June and August 2025. Participants completed the Buss-Perry Aggression Questionnaire, which measures physical aggression, verbal aggression, anger, and hostility. Clinical data, including fasting blood glucose, insulin, lipid profile, and glycated hemoglobin (HbA1c) levels, were recorded. Individuals with diabetes were further stratified by HbA1c levels to examine the association between glycemic control and aggression. Aggression scores were significantly higher in patients with diabetes compared to those without (P < .05), and HbA1c levels positively correlated with Buss-Perry Aggression Questionnaire scores within the diabetes group (R = 0.549, P < .05). Fasting blood glucose, insulin, total cholesterol, and low-density lipoprotein levels were also elevated in individuals with diabetes. Poor glycemic control was associated with higher aggression levels, potentially reflecting alterations in mood regulation and impulse control. Study limitations include the single-center design, the observational nature, and the short follow-up period, which restrict causal inferences. These findings highlight the importance of comprehensive diabetes care that integrates behavioral assessments alongside metabolic monitoring and suggest the need for further longitudinal research to clarify the relationship between glycemic dysregulation and aggression.