Relationship between rotating shift work and white blood cell count, white blood cell differential count, obesity, and metabolic syndrome of nurses

This study investigated the relationship between working rotating shifts and white blood cell (WBC) count, WBC differential count (DC), obesity, and metabolic syndrome of nurses. Samples were obtained from a total of 720 nurses who had received health checkups at a large teaching hospital in Taiwan. Among these nurses, 500 worked rotating shifts, and the remaining 220 nurses worked fixed daytime shifts. We used binary logistic regression to identify the risk factors of obesity or metabolic syndrome. The results indicate that nurses working rotating shifts had a significantly higher WBC count than those working fixed daytime shifts. WBC count was an independent factor relating to an overly large waist circumference or overly high body mass index (BMI) of nurses. For every 10(3)/mu L increase in WBC count, the risk of waist circumference exceeding 90 cm and 80 cm respectively in male and female nurses increased by 46%, and for every 10(3)/mu L increase in WBC count, the risk of a BMI 24 kg/m(2) in nurses increased by 50%. Similarly, WBC count and work type were independent factors influencing the metabolic syndrome of nurses. For every 10(3)/mu L increase in WBC count, the risk of metabolic syndrome occurring in nurses increased by 65%. Nurses working rotating shifts were at a 3.34 times greater risk of having metabolic syndrome than those working fixed daytime shifts. The mean age of our participants was 29.54 years old, and only approximately 4% of the participants had metabolic syndrome. Among these nurses, we found that high WBC was correlated with an overly large waist circumference and overly high BMI. Furthermore, the nurses working rotating shifts may have been at greater risk of metabolic syndrome than those working fixed daytime shifts, and increases in WBC were also associated with the occurrence of metabolic syndrome.