# Shifts with Nights and Migraine Prevalence Among Nurses: A Systematic Review and Meta-Analysis

## TL;DR

A review of studies on nurses found no strong evidence that night shifts increase migraine prevalence compared to day-only schedules.

## Contribution

This is the first nurse-specific systematic review and meta-analysis on the relationship between night shifts and migraine prevalence.

## Key findings

- Night-inclusive schedules were not significantly associated with higher migraine prevalence compared to day-only schedules.
- Secondary comparisons of night-work intensity showed inconclusive results due to limited data and inconsistent definitions.
- The evidence base is small and heterogeneous, making it difficult to draw firm conclusions or policy recommendations.

## Abstract

What are the main findings?
In a nurse-specific systematic review and meta-analysis (4 observational studies; total N = 3843, analyzable N = 3323), night-inclusive schedules (fixed nights and/or rotating shifts including nights) were not associated with a statistically significant difference in 1-year migraine prevalence versus day-only/non-night schedules (pooled PR = 0.95, 95% CI 0.82–1.10; I2 = 0%).Secondary night-work intensity comparisons were inconclusive (high vs. low: PR = 1.24, 95% CI 0.46–3.36; high vs. zero nights: PR = 0.85, 95% CI 0.38–1.93), with non-harmonized exposure thresholds and few contributing studies limiting precision and consistency.

In a nurse-specific systematic review and meta-analysis (4 observational studies; total N = 3843, analyzable N = 3323), night-inclusive schedules (fixed nights and/or rotating shifts including nights) were not associated with a statistically significant difference in 1-year migraine prevalence versus day-only/non-night schedules (pooled PR = 0.95, 95% CI 0.82–1.10; I2 = 0%).

Secondary night-work intensity comparisons were inconclusive (high vs. low: PR = 1.24, 95% CI 0.46–3.36; high vs. zero nights: PR = 0.85, 95% CI 0.38–1.93), with non-harmonized exposure thresholds and few contributing studies limiting precision and consistency.

What are the implications of the main findings?
Current nurse-specific evidence does not support strong conclusions or roster-policy recommendations based on migraine prevalence alone, because the evidence base is small, mostly cross-sectional, and relies on heterogeneous exposure definitions and crude PRs.Future research should use prospective designs that distinguish fixed night work from rotating-with-nights schedules and measure shift-pattern features (e.g., irregularity, quick returns, consecutive nights), while assessing sleep/circadian mediators and migraine outcomes beyond prevalence (incidence, attack frequency, chronification, disability, medication use).

Current nurse-specific evidence does not support strong conclusions or roster-policy recommendations based on migraine prevalence alone, because the evidence base is small, mostly cross-sectional, and relies on heterogeneous exposure definitions and crude PRs.

Future research should use prospective designs that distinguish fixed night work from rotating-with-nights schedules and measure shift-pattern features (e.g., irregularity, quick returns, consecutive nights), while assessing sleep/circadian mediators and migraine outcomes beyond prevalence (incidence, attack frequency, chronification, disability, medication use).

Background: Fixed night work and rotating schedules including nights may contribute to migraine via sleep disruption and circadian misalignment, but evidence is inconsistent and definitions vary. This systematic review and meta-analysis compared past-year migraine prevalence in nurses working night-inclusive schedules versus day-only or non-night schedules. Methods: Following PRISMA 2020 and registered in PROSPERO (CRD420261304288), we searched PubMed, Scopus, Web of Science, CINAHL, and the Cochrane Library from inception to 3 February 2026 (English/Spanish). Observational studies in nurses (≥18 years) reporting past-year migraine prevalence by shift pattern were eligible. All included studies assessed past-year prevalence; pooled PRs reflect 1-year prevalence. Crude prevalence ratios (PRs) were calculated from contingency tables and pooled quantitatively. Risk of bias was assessed with the JBI prevalence checklist. Results: We identified 54 records; 4 studies were included (N = 3843) of which 3323 participants contributed to the comparative meta-analysis because complete disaggregated data were available to construct contingency tables. The pooled association between night-inclusive schedules and migraine prevalence was not statistically significant (PR = 0.95, 95% CI 0.82–1.10; I2 = 0%). Secondary intensity contrasts were inconclusive (high vs. low: PR = 1.24, 95% CI 0.46–3.36; high vs. zero nights: PR = 0.85, 95% CI 0.38–1.93). Conclusions: Current nurse-specific evidence does not show a statistically significant difference in migraine prevalence between night-inclusive and non-night schedules; however, the small evidence base and limited generalizability preclude firm conclusions. Future longitudinal studies are needed to clarify this association.