The influence of altered circadian rhythm on sleep quality and cognition among shift workers of KLE Hospital: A comparative study

Objectives: In shift workers, the internal biological clock is disrupted, leading to a substantial deterioration in sleep quality and cognitive abilities. Also, critical thinking, analytical reasoning and making quick decisions for patient management which are of utmost importance become questionable. Aim: To assess the effect of nighttime sleep deprivation on sleep quality and assessment of cognition in nurses doing night shift by doing a comparative study with age and gender-matched day time working controls. Materials and Methods: Ethical clearance was obtained from the institution. The study population of trainee nurses doing night shifts at KLE hospital and age and gender-matched controls doing day duty were selected and enrolled for data collection by inclusion - exclusion criteria and sample size calculation. Pittsburgh Sleep Quality Index questionnaire was used to assess sleep quality over the past 1-month. Montreal cognitive assessment test was conducted to detect the presence of any cognitive impairment among populations assessing 7 components of cognition. Statistical analysis: Mean ±SD was used and ‘p value=0.005’ was considered statistically significant. Results: Mean global PSQI score was 6.68 for shift workers while 5.56 for controls. Mean score for Montreal test was 23.64 for nurses and 27.76 for controls. Conclusion: In shift workers, sleep quality was poor and a significant reduction in cognitive functions like execution and memory recall as compared to day time working control population. These findings are related to the irregularities in the circadian rhythm and the natural cycle of sleep and waking, which in turn deteriorates cognitive abilities.