Department of Neurology, University Hospital of Northern Norway, Tromsø, Norway.
Pain Clinic, University Hospital of Northern Norway, Tromsø, Norway.
Pain. 2023 Aug 1;164(8):1750-1758. doi: 10.1097/j.pain.0000000000002871. Epub 2023 Mar 6.
As pain is processed by an extensive network of brain regions, the structural status of the brain may affect pain perception. We aimed to study the association between gray matter volume (GMV) and pain sensitivity in a general population. We used data from 1522 participants in the seventh wave of the Tromsø study, who had completed the cold pressor test (3°C, maximum time 120 seconds), undergone magnetic resonance imaging (MRI) of the brain, and had complete information on covariates. Cox proportional hazards regression models were fitted with time to hand withdrawal from cold exposure as outcome. Gray matter volume was the independent variable, and analyses were adjusted for intracranial volume, age, sex, education level, and cardiovascular risk factors. Additional adjustment was made for chronic pain and depression in subsamples with available information on the respective item. FreeSurfer was used to estimate vertexwise cortical and subcortical gray matter volumes from the T1-weighted MR image. Post hoc analyses were performed on cortical and subcortical volume estimates. Standardized total GMV was associated with risk of hand withdrawal (hazard ratio [HR] 0.81, 95% confidence interval [CI] 0.71-0.93). The effect remained significant after additional adjustment for chronic pain (HR 0.84, 95% CI 0.72-0.97) or depression (HR 0.82, 95% CI 0.71-0.94). In post hoc analyses, positive associations between standardized GMV and pain tolerance were seen in most brain regions, with larger effect sizes in regions previously shown to be associated with pain. In conclusion, our findings indicate that larger GMV is associated with longer pain tolerance in the general population.
由于疼痛是由广泛的大脑区域网络处理的，因此大脑的结构状态可能会影响疼痛感知。我们旨在研究一般人群中灰质体积（GMV）与疼痛敏感性之间的关联。我们使用了特罗姆瑟研究第七波的 1522 名参与者的数据，这些参与者完成了冷加压试验（3°C，最长时间 120 秒），进行了大脑磁共振成像（MRI），并且有完整的协变量信息。使用从冷暴露中手部撤回的时间作为结果拟合 Cox 比例风险回归模型。GMV 是自变量，分析调整了颅内体积、年龄、性别、教育水平和心血管危险因素。在有慢性疼痛和抑郁信息的子样本中，还进行了针对慢性疼痛和抑郁的调整。使用 FreeSurfer 从 T1 加权 MR 图像估计顶点皮质和皮质下灰质体积。对皮质和皮质下体积估计进行了事后分析。标准化总 GMV 与手部撤回的风险相关（风险比[HR]0.81，95%置信区间[CI]0.71-0.93）。在针对慢性疼痛（HR 0.84，95%CI 0.72-0.97）或抑郁（HR 0.82，95%CI 0.71-0.94）进行额外调整后，该效果仍然显著。在事后分析中，在大多数大脑区域中，标准化 GMV 与疼痛耐受力之间存在正相关关系，在先前与疼痛相关的区域中，效应大小更大。总之，我们的研究结果表明，GMV 较大与一般人群的疼痛耐受力较长有关。
