Ethnic Differences in Responses to Painful Stimuli

描述（由申请人提供）：在我们目前资助的项目中（R 01 AG 033906），我们建议：1）描述患有膝骨关节炎（OA）的老年非裔美国人和非西班牙裔白人在实验性疼痛敏感性、内源性疼痛抑制、临床疼痛和疼痛相关残疾方面的种族差异; 2）确定种族群体在生物、心理和社会文化因素方面的差异及其对疼痛敏感性、疼痛抑制、老年非裔美国人和非西班牙裔白人膝关节OA患者的临床疼痛和残疾;和3）确定疼痛敏感性和疼痛抑制的实验室测量与生物学，心理和社会文化因素介导老年非裔美国人和非西班牙裔白人膝关节OA患者临床疼痛和疼痛相关残疾的种族差异。在这 竞争性修订申请，这是响应国家卫生研究院通知NOT-OD-09-058，恢复法案基金竞争性修订申请，我们提出了一个重要的扩大范围的原始项目。具体而言，目前资助的项目仅涉及招募非裔美国人和非西班牙裔白色膝关节骨关节炎（OA）患者，修订版建议招募一组无膝关节OA的老年非裔美国人和非西班牙裔白色对照受试者。这将使我们能够通过实现两个新颖而重要的科学目标来加快科学的克里思：1）表征先前在非裔美国人和非西班牙裔白人的老年对照人群中的健康年轻人中观察到的疼痛敏感性和内源性疼痛抑制的种族差异;（2）在一个大型的多媒体演示中，种族样本中，膝关节OA患者表现出明显更高实验室疼痛敏感性和降低的内源性疼痛抑制功能，年龄和性别匹配的无膝关节OA的对照组。在上一个资助周期中，我们提供了大量证据，记录了健康的年轻非洲裔美国人，西班牙裔美国人和非西班牙裔白人之间实验疼痛敏感性和内源性疼痛调节的差异。相对于非西班牙裔白人，这两个少数群体表现出显着更大的敏感性，阈上热，冷，缺血刺激。此外，与非西班牙裔白人相比，非裔美国人表现出降低的弥漫性伤害抑制控制（DNIC），表明疼痛抑制能力减弱。然而，这些数据是在年轻人中收集的，重要的是要证明老年非裔美国人和非西班牙裔白人在疼痛敏感性和疼痛抑制方面存在类似的种族差异。此外，迄今为止还没有研究者在多种族队列中确定膝关节OA患者是否表现出全身性痛觉过敏和疼痛抑制能力受损。支持我们的假设将提供新的信息，种族差异的疼痛敏感性和疼痛抑制，并将提供第一个证据，改变内源性疼痛调制老年非洲裔美国人和非西班牙裔白人膝关节骨性关节炎。 公共卫生相关性： 临床疼痛和疼痛相关残疾的种族差异已被充分记录，并且在健康的年轻人中已经报道了实验性疼痛敏感性的种族差异。这项竞争性修订的目的是确定无痛老年非裔美国人和非西班牙裔白人之间是否存在疼痛敏感性和疼痛抑制实验室指标的种族差异。此外，我们打算首次在大型多种族样本中证明，与年龄和性别匹配的无膝关节OA的对照组相比，膝关节OA患者表现出显著更高的实验室疼痛敏感性和降低的内源性疼痛抑制功能。

DESCRIPTION (provided by applicant): In our currently funded project (R01 AG033906), we propose to: 1) characterize ethnic differences in experimental pain sensitivity, endogenous pain inhibition, clinical pain and pain-related disability among older African Americans and non-Hispanic whites with knee osteoarthritis (OA); 2) to determine ethnic group differences in biological, psychological, and sociocultural factors and their contribution to pain sensitivity, pain inhibition, and clinical pain and disability among older African Americans and non-Hispanic whites with knee OA; and 3) to determine whether the combination of laboratory measures of pain sensitivity and pain inhibition along with biological, psychological and sociocultural factors mediate ethnic group differences in clinical pain and pain-related disability among older African Americans and non-Hispanic whites with knee OA. In this competitive revision application, which is responsive to NIH notice NOT-OD-09-058, Recovery Act Funds for Competitive Revision Applications, we propose an important expansion of the scope of the original project. Specifically, the currently funded project involves only the recruitment of African American and non-Hispanic white patients with knee osteoarthritis (OA), and the revision proposes to recruit a cohort of older African American and non-Hispanic white control subjects without knee OA. This will allow us to accelerate the tempo of the science by accomplishing two novel and important scientific aims: 1) characterizing ethnic differences in pain sensitivity and endogenous pain inhibition previously observed in healthy young adults in an older control population of African Americans and non-Hispanic whites; and 2) demonstrating in a large multi-ethnic sample that patients with knee OA exhibit significantly greater laboratory pain sensitivity and reduced endogenous pain inhibitory function compared to age and sex matched controls without knee OA. During the previous funding cycle, we produced substantial evidence documenting differences in experimental pain sensitivity and endogenous pain modulation among healthy young African Americans, Hispanic Americans, and non-Hispanic whites. Relative to non-Hispanic whites, both minority groups evinced significantly greater sensitivity to suprathreshold heat, cold, and ischemic stimuli. Moreover, compared to non-Hispanic whites, African Americans showed reduced diffuse noxious inhibitory controls (DNIC), suggesting diminished pain inhibitory capacity. However, these data were collected in young adults, and it is important to demonstrate that similar ethnic group differences in pain sensitivity and pain inhibition are present in older African Americans and non-Hispanic whites. Moreover, no investigator to date has determined in a multi-ethnic cohort whether knee OA patients exhibit generalized hyperalgeisa and impaired pain inhibitory capacity. Support for our hypotheses will provide novel information regarding ethnic differences in pain sensitivity and pain inhibition and will provide the first evidence of alterations in endogenous pain modulation among older African Americans and non-Hispanic whites with knee OA. PUBLIC HEALTH RELEVANCE: Ethnic differences in clinical pain and pain-related disability have been well documented, and ethnic differences in experimental pain sensitivity have been reported among healthy young adults. The goal of this competitive revision is to determine whether ethnic differences in laboratory measures of pain sensitivity and pain inhibition are present among pain-free older African Americans and non-Hispanic whites. In addition, we intend to demonstrate for the first time in a large multi-ethnic sample, that patients with knee OA exhibit significantly greater laboratory pain sensitivity and reduced endogenous pain inhibitory function compared to age and sex matched controls without knee OA.