Objective For most patients with chronic low back pain (cLBP), the cause is “nonspecific,” meaning there is no clear association between pain and identifiable pathology of the spine or associated tissues. Laypersons and providers alike are less inclined to help, feel less sympathy, dislike patients more, suspect deception, and attribute lower pain severity to patients whose pain does not have an objective basis in tissue pathology. Because of these stigmatizing responses from others, patients with cLBP may feel that their pain is particularly unjust and unfair. These pain-related injustice perceptions may subsequently contribute to greater cLBP severity. The purpose of this study was to examine whether perceived injustice helps explain the relationship between chronic pain stigma and movement-evoked pain severity among individuals with cLBP. Methods Participants included 105 patients with cLBP who completed questionnaires assessing chronic pain stigma and pain-related injustice perception, as well as a short physical performance battery for the assessment of movement-evoked pain and physical function. Results Findings revealed that perceived injustice significantly mediated the association between chronic pain stigma and cLBP severity (indirect effect = 6.64, 95% confidence interval [CI] = 2.041 to 14.913) and physical function (indirect effect = −0.401, 95% CI = −1.029 to −0.052). Greater chronic pain stigma was associated with greater perceived injustice (P = 0.001), which in turn was associated with greater movement-evoked pain severity (P = 0.003). Conclusions These results suggest that perceived injustice may be a means through which chronic pain stigma impacts nonspecific cLBP severity and physical function.

Background: Chronic low back pain (cLBP) is the leading cause of disability, with a significant societal cost. It disproportionately affects non-Hispanic blacks and individuals of lower socioeconomic status. The biopsychosocial framework has been used to study and manage cLBP, yet disparities persist. Objective: The objective of this study was to assess whether self-identified race moderated the relationship between perceived social status and cLBP outcomes (pain interference and pain severity) and investigate whether race moderated the indirect relationship between perceived social status and pain outcomes via depressive symptoms. Methods: Fifty-seven blacks and 48 whites with cLBP were recruited as part of a large ongoing study. Depressive symptoms, objective and subjective measures of socioeconomic status, and pain outcomes were measured. Hayes’ moderated mediation model was used to estimate conditional direct and indirect relationship between these variables. Result: On average black participants reported significantly more pain interference (4.12 [SD=2.65] vs. 2.95 [SD=2.13]) and severity (5.57 [SD=2.27] vs. 3.99 [SD=1.99]) than white participants, (P<0.05). Race moderated the association between perceived social status and pain interference: higher social status decreases pain interference for white participants, but that trend was not observed in black participants. Moreover, race moderated association of perceived social status with depressive symptoms (P<0.001); which mediates the effects of perceived social status on pain outcomes. Conclusion: Higher perceived social status is associated with less severe depressive symptoms, which in turn is associated with less pain severity and less pain interference for whites but not for blacks with cLBP.

Background Biopsychosocial factors above and beyond pathoanatomical changes likely contribute to the severity of chronic low back pain. A pro-nociceptive endogenous pain modulatory balance (↓inhibition and ↑facilitation) may be an important contributor to chronic low back pain severity and physical function; however, additional research is needed to address this possibility. The objective of this study was to determine whether quantitative sensory tests of endogenous pain inhibition and facilitation prospectively predict movement-evoked pain and cLBP severity self-reported on a validated questionnaire. Methods One hundred thirty-four individuals with chronic low back pain were enrolled in this two-session study. During the first study session, temporal summation of mechanical pain and conditioned pain modulation were assessed at the lumbar spine to determine endogenous pain facilitation and inhibition, respectively. One week later, participants returned for a second study session whereby they reported their pain severity and pain interference using the Brief Pain Inventory-Short Form. Movement-evoked pain and physical function capacity were assessed upon completion of the balance, walking, and transition from sit to stand tests of the Short Physical Performance Battery. Results Temporal summation of mechanical pain, but not conditioned pain modulation, significantly and prospectively predicted greater movement-evoked pain and poorer physical function on the Short Physical Performance Battery. Neither temporal summation nor conditioned pain modulation were significantly related to self-reported pain severity or pain interference on the Brief Pain Inventory-Short Form. Conclusions Findings suggest that a pro-nociceptive pain modulatory balance characterized by enhanced pain facilitation may be an important driver of movement-evoked pain severity and poor physical function in individuals with chronic low back pain.

Chronic low back pain (cLBP) is the most common reason for individual suffering and health care utilization in adults. Ample evidence suggests sociodemographic variables and socioeconomic status (SES) influence pain. However, a framework informing associations on race, SES, and the utilization of pharmacologic therapies and provider type are limited—particularly in cLBP. Thus, this study examined the extent to which sociodemographic (i.e., age, race, and gender) and socioeconomic factors (i.e., national area deprivation index, NADI) influence pain treatment (i.e., NSAIDs, opioids, antidepressants, and non-NSAIDs) and provider utilization for cLBP (i.e., no provider care, primary care, or tertiary care). Eligible participants with cLBP completed a series of questionnaires. Of the 174 participants, 58% were women, 59% were non-Hispanic Black (NHB), and the mean age was 46.10 (SD 13.58). Based on NADI distributions by race, NHB participants lived in more socioeconomically disadvantaged neighborhoods (p &lt; 0.001) than non-Hispanic White (NHW) adults. Results suggested that the use of one or more pharmacologic therapies was associated with race (p = 0.021). Specifically, NHW adults were two times more likely to take one or more pharmacologic therapies than NHBs (p = 0.009). NHWs were also more likely to use NSAIDs (p = 0.041) and antidepressants (p &lt; 0.001) than NHBs. Furthermore, provider utilization was significantly associated with gender (p = 0.037) and age (p = 0.018); which suggests older women were more likely to use primary or tertiary care. Findings from this study expand on the existing literature as it relates to associations between disparities in access to healthcare providers and access to medications. Future research should seek to understand differences in age and utilization of primary or tertiary care providers and continue to examine the influence of sociodemographic and SES factors to cLBP and compare with other types of chronic pain.

Background and PurposeHow the Area Deprivation Index (ADI) performs compared to other measures of socioeconomic status (SES) is unknown. The study purpose is to compare the ADI and other measures of SES in their ability to predict pain severity/interference.MethodsFour measures of SES were compared—ADI, income, education, and subjective social status (SSS).ResultsPain severity/interference correlated positively with ADI (r = .396/r = .33), and negatively with income (r = –.507/r = –.428) and education (r = –.271/r = –.102). Criterion scores of the pain severity model suggest income performs best (AIC = 428.29/BIC = 436.22), followed by ADI (AIC = 437.24/BIC = 445.17), with education performing least well (AIC = 446.35/BIC = 454.29). Similar results were seen for the pain interference model.ConclusionsNeighborhood-level factors warrant consideration along with individual-level factors when attempting to understand the impact of SES on chronic low back pain.