Shift Work Ups Cortisol Levels, BMI in Young Adults
Young shift workers have long-term elevated cortisol levels, higher BMI than young day workers
MONDAY, Oct. 10 (HealthDay News) -- For young adults, shift work (work performed out of standard working hours) is associated with long-term elevated cortisol levels and increased body mass index (BMI), according to a study published online Aug. 31 in the Journal of Clinical Endocrinology & Metabolism.
Laura Manenschijn, M.D., from the Erasmus Medical Center in Rotterdam, Netherlands, and colleagues investigated the changes in long-term cortisol levels due to shift work by comparing cortisol levels in hair samples of 33 shift and 89 day workers. Methanol was used to extract cortisol from the hair samples, which was then measured using enzyme-linked immunosorbent assay. BMI was determined using height and weight measurements.
The investigators found that hair cortisol levels were significantly higher in the shift workers than in the day workers (47.32 versus 29.72 pg/mg hair). After stratifying by median age, only the younger shift workers (<40 years) had significantly elevated cortisol levels compared to day workers (48.53 versus 26.42 pg/mg hair). Younger shift workers had significantly higher BMI than day workers (27.2 versus 23.7). There was a positive association seen for hair cortisol levels and BMI.
"Shift work at young-adult age is associated with elevated long-term cortisol levels and increased BMI. Elevated cortisol levels and BMI may contribute to the increased cardiovascular risk found in shift workers," the authors write.