Evaluation of the Impact of Shift Work on Cognitive Functions: Possible Implications for Work Capacity

Introduction: Shift work refers to a work system where employees are assigned to predetermined schedules, including rotating shifts, to ensure continuous or intermittent operations. This system requires workers to perform duties at varying hours over a defined period. The demands of these shifts are particularly significant in healthcare, where 24/7 patient care is crucial. This system exposes workers to intense psychophysical stress, increasing the risk of burnout and health-related complications. Shift work disrupts circadian rhythms, leading to sleep disorders and impairments in attention, decision-making, and executive function. Research suggests that long-term shift work accelerates cognitive aging, raising the risk of neurocognitive decline. Identifying risk and protective factors is crucial to sustaining cognitive function, productivity, and well-being in aging workers.

Methods: The sample includes healthcare workers from the Occupational Medicine Unit of a University hospital in Southern Italy, who were recruited as part of the mandatory health surveillance to which they are subjected according to the legislation in force in Italy, comprising a group of shift workers and a control group with no night shifts. Neuropsychological assessments were performed pre- and post-shift using standardized tests: SDMT – Digit Symbol Modalities Test (processing speed and attention), TMT A/B - Trail Making Test (cognitive flexibility), DS - Digit Span Test (working memory), WAI - Work Ability Index (work capacity), ESS - Epworth Sleepiness Scale (daytime sleepiness), PSQI - Pittsburgh Sleep Quality Index (sleep quality), and QMCI - Quick Mild Cognitive Impairment screen (cognitive impairment screening).

Results: The study analyzed 30 shift workers (mean age 42 ± 9.58) and 30 non-shift workers (mean age 32 ± 3.41). Shift workers had greater prevalence of neurological or metabolic disorders (80% versus 30%). Post-night shift, shift workers showed significant declines in SDMT (p < 0.001), TMT-A/B (p < 0.001), and DS forward (p = 0.007), indicating deficits in processing speed, cognitive flexibility, and working memory. WAI scores were lower in shift workers (p < 0.001), correlating with cognitive decline. ESS revealed increased daytime sleepiness post-night shift (p = 0.014), while PSQI indicated significantly poorer sleep quality (p = 0.008). QMCI scores confirmed cognitive decline in shift workers post-night shift (p < 0.001).

Conclusion: Shift work, particularly night shifts, impairs cognitive function and work capacity due to circadian rhythm disruptions and sleep deprivation. Early identification of neurocognitive decline is essential in occupational medicine to ensure worker safety and efficiency. Preventive strategies should include ergonomic shift scheduling, reduced night shift hours, and structured rest periods to mitigate cognitive decline. Workplace interventions promoting cognitive health through lifestyle modifications, sleep management, and psychometric monitoring may improve long-term well-being and job performance in shift-dependent professions.

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Artikel online veröffentlicht:
08. Oktober 2025