McLain Natalie, Cavaleri Rocco, Kutch Jason
Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, California, USA.
Brain Stimulation and Rehabilitation (BrainStAR) Lab, School of Health Sciences, Western Sydney University, Sydney, New South Wales, Australia.
Eur J Pain. 2025 Mar;29(3):e4737. doi: 10.1002/ejp.4737. Epub 2024 Oct 7.
Low peak alpha frequency (PAF) is an electroencephalography (EEG) outcome associated reliably with high acute pain sensitivity. However, existing research suggests that the relationship between PAF and chronic pain is more variable. This variability could be attributable to chronic pain groups typically being examined as homogenous populations, without consideration being given to potential diagnosis-specific differences. Indeed, while emerging work has compared individuals with chronic pain to healthy controls, no previous studies have examined differences in PAF between diagnoses or across chronic pain subtypes.
To address this gap, we reanalysed a dataset of resting state EEG previously used to demonstrate a lack of difference in PAF between individuals with chronic pain and healthy controls. In this new analysis, we separated patients by diagnosis before comparing PAF across three subgroups: chronic widespread pain (n = 30), chronic back pain (n = 38), and healthy controls (n = 87).
We replicate the original finding of no significant difference between chronic pain groups and controls, but also find that individuals with widespread pain had significantly higher global average PAF values than those of people with chronic back pain [p = 0.028, β = 0.25 Hz] after controlling for age, sex, and depression.
These novel findings reveal PAF values in individuals with chronic pain may be diagnosis-specific and not uniformly shifted from the values of healthy controls. Future studies should account for diagnosis and be cautious with exploring homogenous 'chronic pain' classifications during investigations of PAF.
Our work suggests that, contrary to previous hypotheses, inter-individual differences in PAF reflect diagnosis-specific mechanisms rather than the general presence of chronic pain, and therefore may have important implications for future work regarding individually-tailored pain management strategies.
低峰阿尔法频率（PAF）是一种脑电图（EEG）结果，与高急性疼痛敏感性可靠相关。然而，现有研究表明，PAF与慢性疼痛之间的关系更具变异性。这种变异性可能归因于慢性疼痛群体通常被视为同质人群，而未考虑潜在的诊断特异性差异。事实上，虽然新出现的研究已将慢性疼痛患者与健康对照进行了比较，但以前没有研究检查过不同诊断之间或不同慢性疼痛亚型之间PAF的差异。
为了填补这一空白，我们重新分析了一个静息态EEG数据集，该数据集先前用于证明慢性疼痛患者与健康对照之间PAF没有差异。在这项新分析中，我们在比较三个亚组的PAF之前，按诊断对患者进行了分组：慢性广泛性疼痛（n = 30）、慢性背痛（n = 38）和健康对照（n = 87）。
我们重复了慢性疼痛组与对照组之间无显著差异的原始发现，但也发现，在控制年龄、性别和抑郁后，广泛性疼痛患者的全球平均PAF值显著高于慢性背痛患者[p = 0.028，β = 0.25Hz]。
这些新发现表明，慢性疼痛患者的PAF值可能具有诊断特异性，并非一律偏离健康对照的值。未来的研究应考虑诊断因素，并在PAF研究中谨慎探索同质的“慢性疼痛”分类。
我们的研究表明，与先前的假设相反，PAF的个体差异反映的是诊断特异性机制，而非慢性疼痛的普遍存在，因此可能对未来关于个性化疼痛管理策略的研究具有重要意义。
