Effects of shift work on abdominal obesity among 20–39-year-old female nurses: a 5-year retrospective longitudinal study

Abstract

BackgroundThis study aimed to investigate the effects of shift work on abdominal obesity among young and middle-aged female nurses during a 5-year retrospective study.MethodsThis retrospective study included female nurses (20–39 years old) who worked at a university hospital in Korea and had available health screening results from 2010–2015. Among 2,611 employees, 934 healthy 20–39-year-old female nurses were identified, and data regarding their demographic information (age and date of employment), waist circumferences (WC), and lifestyle factors (alcohol and exercise) were obtained. Abdominal obesity was defined as a WC of ≥80 cm, based on the World Health Organization’s Asia-West Pacific standard in 2000. The mean WC change from baseline was analyzed using the paired t test, and the association between shift work and abdominal obesity was analyzed using the generalized estimating equation.ResultsCompared to all day workers (both age groups), the 20–29-year-old nurses did not exhibit significant changes in WC at each follow-up. However, among the 30–39-year-old nurses, shift workers exhibited a significant change in WC (vs. baseline) during years 4 and 5, compared to day workers. After adjusting for effective confounders and stratifying the participants according to age, the 20–29-year-old nurses exhibited an odds ratio of 3.21 (95 % confidence interval: 1.29–7.98) for shift work-associated obesity, although the odds ratio for the 30–39-year-old nurses was not statistically significant.ConclusionIn the study population, shift work was associated with a significant change in mean WC among 30–39-year-old nurses, and the shift work-associated risk of abdominal obesity was significant among 20–29-year-old nurses. These results indicate that shift work may influence abdominal obesity differently in 20–29-year-old and 30–39-year-old female nurses.

Meta‐analysis on shift work and risks of specific obesity types

“…Ten studies found an increased risk of obesity from rotating shift work; three studies reported an increased risk from permanent night work, but only one study reported an increased risk from irregular shift work. Moreover, Bushnell et al .…”

“…Six articles reported results with occupationally mixed populations. Eleven studies focused on female workers, and five focused on male participants. Twelve studies included participants of both genders.…”

“…Twelve studies included participants of both genders. Nine studies analysed a total of 109,834 East Asian participants, including the populations from Japan, Korea, Malaysia and Taiwan. Overall, 15 articles (>50%) had good quality according to the STROBE statement guidelines, and the remaining 13 studies were all rated as fair quality.…”

“…Another 11 studies reported OR on the risk for BMI ≥30 kg/m 2 . Nine studies reported OR for abdominal obesity. Two studies reported OR for weight/BMI increase.…”

Relationship between night shift work, eating habits and BMI among nurses in Lebanon

“…Night shift work is associated with an increase in BMI and can lead to overweight and obesity [11][12][13][14][15][16]. Cumulative night shift work is strongly related to an increase in BMI, waist circumference [17][18][19], hip circumference and waist to hip ratio [20]. Weight gain associated with night shift work may be the result of an excess of calorie intake and a lack of physical activity during night [21,22].…”