EMGO Institute, VU University Medical Centre, Department of General Practice, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands Arthritis Research Campain National Primary Care Centre, Keele University, Keele, Staffordshire, UK EMGO Institute, VU University Medical Centre, Department of Clinical Epidemiology and Biostatistics, The Netherlands.
Pain. 2010 Aug;150(2):351-357. doi: 10.1016/j.pain.2010.05.030. Epub 2010 Jun 22.
So far, most studies on the association between pain and fatigue have used cross-sectional data. We analysed the possibilities for a temporal relationship between pain and fatigue in a cohort study of patients presenting with fatigue in primary care. Of 856 recruited patients, 642 (75%) completed postal questionnaires after the consultation, and at one, four, eight and 12 months follow-up, with completion rates ranging from 82% to 88%. Pain was measured using the Short-Form health survey (SF-36) and fatigue using the severity scale of the Checklist Individual Strength (CIS). Longitudinal associations were analysed using generalised estimated equations (GEE). We used three different models assessing possible relationships between the symptoms in time, either in the same intervals or with a time-lag, suggesting either a synchronous or temporal association. The regression coefficients were strongest in the model assessing synchronous change, indicating that a one-point improvement in pain was associated with a 0.25 improvement in fatigue in the same time interval (adjusted for potential confounding). Baseline duration of fatigue and expectations of its future course significantly modified the association in this model, with stronger associations between changes in pain and fatigue found in patients with a shorter duration of fatigue or more positive expectations. The models using a time lag showed a significant but inverse association between changes in pain and subsequent changes in fatigue. The results indicate that changes in pain and fatigue are directly related in time, rather than showing temporal associations.
迄今为止，大多数关于疼痛与疲劳之间关联的研究都使用了横断面数据。我们在一项初级保健中出现疲劳的患者队列研究中分析了疼痛与疲劳之间存在时间关系的可能性。在招募的 856 名患者中，有 642 名（75％）在就诊后完成了邮政问卷调查，并在 1、4、8 和 12 个月的随访中完成了问卷调查，完成率从 82％到 88％不等。疼痛使用健康调查简表（SF-36）进行测量，疲劳使用个体力量检查表（CIS）的严重程度量表进行测量。使用广义估计方程（GEE）分析纵向关联。我们使用了三种不同的模型来评估症状之间在同一时间或有时间滞后的情况下可能存在的关系，提示存在同步或时间关联。在评估同步变化的模型中，回归系数最强，表明疼痛改善一个点与同一时间间隔内疲劳改善 0.25 点相关（调整了潜在混杂因素的影响）。疲劳的基线持续时间和对其未来病程的期望显著改变了该模型中的关联，在疲劳持续时间较短或期望更为积极的患者中，疼痛和疲劳变化之间的关联更强。使用时间滞后的模型显示疼痛变化与随后的疲劳变化之间存在显著但相反的关联。结果表明，疼痛和疲劳的变化在时间上直接相关，而不是表现出时间关联。
