Nurullah İlhan
Eurasian Journal of Medical Investigation - 2025;9(3):131-140
Objectives: Chronotype, an individual's circadian preference for activity and rest, has been increasingly recognized as a potential factor influencing cancer risk and patient outcomes. However, limited research has explored chronotype distribution among cancer patients and its association with sociodemographic features and cancer types. Methods: This cross-sectional study was conducted in an oncology clinic at a research and training hospital in Turkey and included adults aged 18 years or older with a cancer diagnosis, excluding those with bipolar disorder, psychosis, or intellectual disability. Chronotype was assessed using the Turkish-validated Morningness-Eveningness Questionnaire (MEQ), and participants were categorized into five chronotype groups, with moderate and definite evening types combined into a single evening-type tendency group due to low frequency. Sociodemographic and clinical data were collected through structured forms. Statistical analyses included Fisher's Exact test, ANOVA, and univariate logistic regression, with significance set at p<0.05. Results: Intermediate and morning chronotypes were more prevalent than evening types. Chronotype showed significant associations with gender, education level, and employment status. Definite morning chronotypes demonstrated a substantially lower likelihood of breast cancer compared to evening types (OR = 0.04, p = 0.023), while digestive system cancers were more frequent in morning chronotypes without statistical significance (OR = 0.60, p = 0.136). No significant association was observed with lung cancer. Conclusion: These findings suggest that chronotype may influence cancer risk and patient characteristics. Integrating circadian preference assessment into cancer prevention and supportive care strategies could improve personalized management. Further longitudinal studies are warranted to clarify causal mechanisms and validate these associations.
