McLaughlin Catherine, Bowman Marilyn L, Bradley Cheryl L, Mistlberger Ralph E
Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada.
Chronobiol Int. 2008 Apr;25(2):455-70. doi: 10.1080/07420520802118269.
Seasonal effects on shift-work tolerance were assessed using the Standardized Shiftwork Index and the 21-item Hamilton Depression Scale. Participants (N=88) mainly worked a two-day, two-night, four-off rotation with 12 h shifts changing at 06:00 and 18:00 h in Vancouver, Canada. At this latitude (approximately 49 degrees N), daylength varies seasonally from approximately 16 to approximately 8 h, and both daily commutes occur in the dark in mid-winter and in sunlight in mid-summer. Questionnaires were completed twice, near the summer and winter solstices (order counterbalanced). Outcome variables were mood, general psychological health, sleep quality, chronic fatigue, physical health, job satisfaction, and social and domestic disruption. Of these, general psychological health and mood were significantly worse in winter, while sleep was more disturbed in summer. In winter, 31% exceeded the cutoff for psychological distress, and >70% scored in the higher than normal range for depressive symptoms. In summer, the proportions dropped to 19% and 53%, respectively. Measures of physical health and psychosocial well-being showed no seasonal effects. Relationships among explanatory and outcome variables, assessed by linear regression and canonical correlations, were also stable across season. Neuroticism was the strongest predictor of tolerance to shift work. Age was predictive only of sleep disturbance in both summer and winter. These results indicate that time of year can affect important outcome measures in shift-work assessment and intervention studies. The high average scores on measures of psychological distress and depression in winter suggest that at northern latitudes, some shift schedules may increase the risk of seasonal-type depression.
使用标准化轮班工作指数和21项汉密尔顿抑郁量表评估季节对轮班工作耐受性的影响。参与者（N = 88）主要进行两天白班、两天夜班、四天休息的轮班制，在加拿大温哥华，12小时轮班时间在06:00和18:00更换。在这个纬度（约北纬49度），白昼时长随季节变化，从约16小时到约8小时不等，并且在冬至时两次日常通勤都是在黑暗中进行，而在夏至时则是在阳光下。在夏至和冬至附近（顺序平衡）分别完成两次问卷调查。结果变量包括情绪、总体心理健康、睡眠质量、慢性疲劳、身体健康、工作满意度以及社交和家庭干扰。其中，总体心理健康和情绪在冬季明显更差，而睡眠在夏季更易受到干扰。在冬季，31%的人超过了心理困扰的临界值，超过70%的人抑郁症状得分高于正常范围。在夏季，这两个比例分别降至19%和53%。身体健康和心理社会幸福感的测量结果未显示出季节性影响。通过线性回归和典型相关分析评估的解释变量与结果变量之间的关系在不同季节也保持稳定。神经质是轮班工作耐受性最强的预测因素。年龄仅在夏季和冬季对睡眠干扰有预测作用。这些结果表明，一年中的时间会影响轮班工作评估和干预研究中的重要结果指标。冬季心理困扰和抑郁测量的平均得分较高，这表明在北纬地区，一些轮班时间表可能会增加季节性抑郁症的风险。
