Kreddig Nina, Hasenbring Monika I
Department of Medical Psychology and Medical Sociology, Faculty of Medicine, Ruhr-University of Bochum, Universitätsstrasse, 44780 Bochum, Germany.
Scand J Pain. 2017 Jul;16:105-111. doi: 10.1016/j.sjpain.2017.03.009. Epub 2017 May 11.
Anxiety and fear are increasingly seen as related, but distinct concepts, with anxiety describing a reaction to unclear or future threats, and fear to immediate threats. Anxiety and fear both play influential roles in pain. Yet, the two concepts have not been clearly distinguished in pain research. Their reported intensity differs between the sexes, and sex differences in the way pain anxiety and fear of (re)injury relate to pain intensity have been found separately in previous studies. However, they seem to be of a curious nature: In one study, pain anxiety was associated with elevated pain intensity in men, while in another, fear of (re)injury was associated with elevated pain intensity in women. This indicates a moderator effect of sex. The present study is the first to unite previous findings, and to show a more integrative picture, by examining and discussing this moderator effect of sex in a joint study of both pain-related anxiety and fear in both sexes.
In 133 patients (mean age 43.6 years, 62% female) with chronic low back pain (mean duration 7.7 years), sex differences were examined with correlations and a multiple linear regression analysis with interaction terms. Differences between subgroups of low and high anxiety/fear were explored via t-tests, following previous studies.
Sex was supported as a moderator in the association of pain intensity with pain anxiety (PASS-20), and fear of (re)injury (TSK). Higher pain intensity was linked to higher pain anxiety only in men, and to higher fear of (re)injury only in women. A basic regression model with fear, anxiety, sex and disability as predictors (R=.14, F(4,123)=3.24, p=.042) was significantly improved by the addition of the interaction terms Fear×Sex and Anxiety×Sex (R=.18, F(2,121)=4.90, p=.001), which were both shown as significant predictors for pain intensity. Further t-tests revealed a significant difference in pain intensity between high and low anxiety in men (t(47)=-2.34, p=.023, d=-.43), but not in women. Likewise, a significant difference in pain intensity between high and low fear showed in women (t(80)=-2.28, p=.025, d=-.42), but not in men.
The results support a moderator effect of sex and suggest differential mechanisms between the sexes in pain anxiety and fear in development and maintenance of back pain. The current study is the first to report and analyse this moderator effect. As potential underlying mechanisms, evolution and socialization are discussed, which may elucidate why fear might be more relevant for pain in women, and anxiety more relevant for pain in men.
The results indicate the need for a more cautious conceptual separation of fear and anxiety in research. Future studies on fear and anxiety in pain should be aware of the distinction, in order to avoid reporting only half of the picture. The next step would be to solidify the results in different samples, and to examine whether a distinction between anxiety and fear in the sexes could have any benefit in pain treatment.
焦虑和恐惧越来越被视为相关但不同的概念，焦虑描述对不明确或未来威胁的反应，而恐惧针对直接威胁。焦虑和恐惧在疼痛中均发挥着重要作用。然而，在疼痛研究中这两个概念尚未得到清晰区分。它们报告的强度存在性别差异，并且在先前的研究中，疼痛焦虑与对（再）受伤的恐惧与疼痛强度之间的性别差异是分别发现的。然而，它们似乎具有一种奇特的性质：在一项研究中，疼痛焦虑与男性疼痛强度升高相关，而在另一项研究中，对（再）受伤的恐惧与女性疼痛强度升高相关。这表明存在性别的调节作用。本研究首次整合先前的研究结果，并通过在一项关于两性疼痛相关焦虑和恐惧的联合研究中检验和讨论性别的这种调节作用，呈现出一幅更综合的图景。
在133例慢性下腰痛患者（平均年龄43.6岁，62%为女性，平均病程7.7年）中，通过相关性分析以及带有交互项的多元线性回归分析来检验性别差异。按照先前的研究，通过t检验探索高焦虑/恐惧和低焦虑/恐惧亚组之间的差异。
性别被证实为疼痛强度与疼痛焦虑（PASS - 20）以及对（再）受伤的恐惧（TSK）之间关联的调节因素。仅在男性中，较高的疼痛强度与较高的疼痛焦虑相关，而仅在女性中，较高的疼痛强度与较高的对（再）受伤的恐惧相关。以恐惧、焦虑、性别和残疾作为预测因素的基本回归模型（R =.14，F(4,123)=3.24，p =.042），通过添加交互项恐惧×性别和焦虑×性别后得到显著改善（R =.18，F(2,121)=4.90，p =.001），这两个交互项均被证明是疼痛强度的显著预测因素。进一步的t检验显示，男性中高焦虑和低焦虑之间的疼痛强度存在显著差异（t(47)= - 2.34，p =.023，d = -.43），而女性中不存在；同样，女性中高恐惧和低恐惧之间的疼痛强度存在显著差异（t(80)= - 2.28，p =.025，d = -.42），而男性中不存在。
结果支持性别的调节作用，并表明在腰痛的发生和维持过程中，两性在疼痛焦虑和恐惧方面存在不同机制。本研究首次报告并分析了这种调节作用。作为潜在的潜在机制，讨论了进化和社会化因素，这可能阐明为什么恐惧可能与女性的疼痛更相关，而焦虑与男性的疼痛更相关。
结果表明在研究中需要更谨慎地对恐惧和焦虑进行概念区分。未来关于疼痛中恐惧和焦虑的研究应意识到这种区别，以避免只呈现部分情况。下一步将是在不同样本中巩固这些结果，并研究两性中焦虑和恐惧的区分在疼痛治疗中是否有任何益处。
