Moosavi Saeideh, Ghalenoei Mehran, Amerzadeh Mohammad, Variani Ali Safari
Student Research Committee, School of Public Health, Qazvin University of Medical Sciences, Qazvin, Iran.
Social Determinants of Health Research Center, Research Institute for Prevention of Non-Communicable Diseases, Qazvin University of Medical Sciences, Qazvin, Iran.
BMC Nurs. 2025 Mar 26;24(1):324. doi: 10.1186/s12912-025-02850-2.
Nurses work 24-hour shifts due to the critical importance of patient care. The human body has a circadian rhythm that regulates many physiological activities. Shift work is associated with decreased melatonin levels and disruption of the circadian rhythm. Given the vital role of cognitive functions such as working memory and attention, this study investigated the impact of circadian rhythm disturbances on the cognitive performance of intensive care unit (ICU) nurses in Qazvin City, Iran.
The study population consisted of 36 nurses. The assessment tools included a demographic questionnaire, a circadian rhythm questionnaire, and cognitive function tests (attention and working memory) using the Stroop Test and Wechsler Adult Intelligence Scale, administered at the beginning and end of each of the three shifts. The data was analyzed using descriptive statistics, including mean, standard deviation, and frequency percentages. The Kolmogorov-Smirnov test was used to determine the normality of the data. The data analysis involved analytical statistics using mixed-effects models performed using R software version 4. The significance level was at p < 0.05 for the present study.
The nurses exhibited a high degree of circadian rhythm inflexibility, with 83.3% classified as " inflexibile" and 91.7% as " vigorous ".|The nurses' cognitive performance was highest during the morning shift, with better attention and working memory abilities. A one-unit increase in the stability and amplitude of the circadian rhythm was associated with reductions in memory span, congruent response time, and incongruent response time during the evening and night shifts.
Given the observed decline in specific cognitive functions during evening and night shifts, the likelihood of increased errors during these shifts is heightened. The cumulative effect of circadian rhythm disruptions can manifest as diminished cognitive performance. The rhythm stability and amplitude could serve as predictive indicators for staffing shift work systems to prevent errors and enhance the system's efficiency.
由于患者护理至关重要，护士需进行24小时轮班工作。人体有调节多种生理活动的昼夜节律。轮班工作与褪黑素水平降低及昼夜节律紊乱有关。鉴于工作记忆和注意力等认知功能的重要作用，本研究调查了昼夜节律紊乱对伊朗加兹温市重症监护病房（ICU）护士认知表现的影响。
研究对象包括36名护士。评估工具包括一份人口统计学调查问卷、一份昼夜节律调查问卷以及使用斯特鲁普测验和韦氏成人智力量表进行的认知功能测试（注意力和工作记忆），在三个班次的开始和结束时进行。数据采用描述性统计分析，包括均值、标准差和频率百分比。使用柯尔莫哥洛夫-斯米尔诺夫检验来确定数据的正态性。数据分析涉及使用R软件版本4进行的混合效应模型分析统计。本研究的显著性水平为p < 0.05。
护士表现出高度的昼夜节律不灵活性，83.3%被归类为“不灵活”，91.7%为“活跃”。护士的认知表现在早班时最高，注意力和工作记忆能力更好。昼夜节律的稳定性和振幅每增加一个单位，与晚班和夜班期间的记忆广度、一致反应时间和不一致反应时间的减少相关。
鉴于观察到晚班和夜班期间特定认知功能下降，这些班次出错的可能性增加。昼夜节律紊乱的累积效应可能表现为认知表现下降。节律稳定性和振幅可作为预测指标，用于安排轮班工作系统人员，以防止出错并提高系统效率。
