Breast cancer and shift work in women with disability in Nuevo Leon, Mexico

Abstract

Introduction: Breast cancer is the most common malignant tumor in women worldwide. Since 2007, the IARC has classified night or rotating shifts as potential carcinogens, emphasizing the need to assess their effects on the Mexican population. This study examined the association between disability due to breast cancer and work shifts (day, night, or rotating) among women from Nuevo León delegation of the Mexican Social Security Institute.

Method: A retrospective, descriptive, and observational study was conducted in 529 female workers with disability due to breast cancer, registered between 2012 and 2023. Labor, clinical, and demographic variables were analyzed using statistical tests in SPSS program.

Results: Of all disability reports for malignant tumors, 39.5% were attributed to breast cancer, with prevalence rates of 73.23% in day shifts, 21.26% in rotating shifts, and 5.51% in night shifts. The median loss of work capacity was 55%; rotating shifts had the longest periods of disability (207 days). Advanced clinical stages (IIIA and IV) predominated, negatively impacting prognosis and workforce reintegration. Occupations with the highest prevalence included basic support and administrative roles.

Conclusions: Rotating shifts may be associated with hormonal and metabolic disruptions that increase breast cancer risk. This evidence underscores the importance of implementing labor prevention policies, surveillance programs, and early detection strategies to reduce risks among female workers, particularly those in night and rotating shifts.