Association between night shift work and the risk of type 2 diabetes mellitus: a cohort-based meta-analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of observational cohort studies
PubMed 39696306 · doi:10.1186/s12902-024-01808-w
What was done
The authors systematically searched PubMed, Web of Science, EBSCO, and the Cochrane Library through February 2024 to evaluate the link between night shift work and type 2 diabetes mellitus (T2DM) incidence. They meta-analyzed hazard ratios (HR) and 95% confidence intervals (95% CI) across 10 cohort studies from 9 published articles, including subgroup analyses by sex, BMI, and shift work duration.
What was found
Night shift workers had a 30% higher risk of developing T2DM compared to daytime workers (HR = 1.30, 95% CI: 1.18–1.43, P < 0.001). Subgroup results showed: - Sex: Higher incidence in females (HR = 1.28, 95% CI: 1.16–1.41), but no statistically significant association in males (95% CI: 0.89–2.63; point estimate not reported). - BMI: Significantly increased risk in individuals with BMI > 30 kg/m² (HR = 1.14, P = 0.007), but not in those with BMI ≤ 30 kg/m² (P = 0.255). - Duration: Higher risk for > 10 years of night shift work (HR = 1.17, 95% CI: 1.10–1.24) compared to ≤ 10 years (HR = 1.06, 95% CI: 1.03–1.10).
Why it matters
This review synthesizes prospective cohort evidence demonstrating that prolonged exposure to night shifts and baseline obesity are associated with greater risk of developing type 2 diabetes.
Limits
The underlying studies are observational cohorts susceptible to residual confounding from diet, sleep disruption, and lifestyle. The male subgroup analysis had a small sample size with wide confidence intervals. Total participant count, shift schedule definitions, and statistical heterogeneity metrics were not reported in the abstract.
Cited by
- supports Shift work is a known carcinogen and increases the risk of developing diabetes and dementia.