Participants provided written informed consent for participation.We assessed the prevalence, severity, and duration of pain using questions from the Brief Pain Inventory .We asked participants whether they had experienced pain or taken medicine for pain in the past week. Next, we asked participants to rate their average pain over the past week on a 0–10 numeric rating scale, where 0 was ‘no pain’ and 10 was ‘pain as bad as you can imagine’. We categorized average pain ratings as no to mild , moderate , and severe pain.If individuals indicated in response to the first question that they had not experienced pain in the past week, we classified their pain as ‘zero’. We asked participants with pain how long they had experienced their pain. We categorized these answers as ‘less than 3 months’, ‘3 months to 5 years’, and ‘more than 5 years’. We categorized participants with moderate to severe pain lasting over 3 months as experiencing chronic pain.We asked participants to rate how their pain interfered with their enjoyment of life and general activity on a scale of 0 to 10 .3 We categorized these responses as mild , moderate , and severe interference . We inquired about health conditions that are prevalent in this population and likely associated with pain, including arthritis, human immunodeficiency virus , diabetes, and traumatic brain injury .To assess for HIV infection, we asked participants whether they had ever been tested and if so, for the result of the test. We asked participants whether a clinician had ever told them that they had diabetes or arthritis. To evaluate for a history of likely TBI,cannabis drying racks we asked participants whether they had ever been hit in the head, and if so, whether any of the three most severe head injuries resulted in loss of consciousness.To assess the association of chronic pain with living environment, we used participants’ self report of the places where they had stayed for the prior 6 months.
We performed a cluster analysis to create a classification of living environments.We used Ward’s linkage to minimize the sum-of-square differences within groups. We performed visual analysis of a dendrogram representing the structure of the data to select the optimum number of clusters. Using bivariate matrices, we confirmed that we could identify natural groupings. We used kmedians cluster methodology to verify cluster classifications.We performed chi-square tests of significance for differences in the independent variables representing the domains we hypothesized to be associated with chronic moderate to severe pain. These results informed a multivariate logistic regression analysis in which we included all hypothesized variables that were associated at a p<0.2 level in the bivariate analyses. Then, we used backward selection to define our final, reduced model. We performed a sensitivity analysis to evaluate missing data in our final model by assuming that missing dichotomous variables were either positive or negative and measuring their effects on the observed odds ratios and confidence intervals. We performed all analyses with SAS 9.4 . A total of 350 participants completed the enrollment interview .Two people did not provide information on pain, leaving a sample of 348. The cohort was 77.3% male, 79.6% African American, and 74.4% high school-educated . The median age was 58 years, with a range from 50–80 years. Almost half of participants first experienced homelessness after turning. Almost half of participants reported being diagnosed with arthritis. Three-quarters endorsed a personal history of abuse. Nearly a third reported symptoms consistent with PTSD and over a third reported recent anxiety. Symptoms of depression and substance use problems were common .In the overall cohort, 17.2% reported moderate pain and 39.4% reported severe pain over the past week. Approximately half of participants reported experiencing chronic moderate to severe pain. The majority of participants experiencing pain reported chronic pain . The median duration of both moderate and severe pain was 5 years .
Most individuals with pain reported that it interfered with both general activity and life enjoyment. Participants with severe pain reported the most interference . We derived four categories of participants based on their current living environments: unsheltered , cohabiters , multiple institution users , and recently homeless . Participants in the unsheltered group spent a large portion of the prior 6 months in unsheltered locations; cohabiters spent a large portion of their time staying with friends and family; multiple institution users stayed in multiple locations including shelters, transitional housing, motels, and jails ; and renters, who had recently become homeless, spent a large portion of their time in rental housing.In the bivariate analyses, compared with the no to mild pain group, participants with chronic moderate to severe pain described significantly more depressive symptoms, PTSD, recent anxiety, arthritis, histories of traumatic brain injury, and histories of abuse . We did not find an association with living environment, gender, race, or substance use. We included significant variables as well as those that met the pre-specified criterion of p<0.2 in our full multivariate model. In our reduced multivariate model, we found significant associations between PTSD , arthritis , and a history of abuse with chronic pain . Depressive symptoms were not significant in the reduced multivariate model.In a sample of adults 50 and older experiencing homelessness, almost half of the participants reported chronic moderate to severe pain. While definitions for chronic pain vary within the literature, the prevalence of chronic pain in the general population ranges from 2.0% to 40.0%.Studies of pain in community living older adults found the prevalence of any pain to range from 28%–59%.Studies of pain in nursing home residents found the prevalence of pain to range between 32%–57%, with more than half of that reported to be moderate-severe pain.Despite the younger age of our sample, we found a higher prevalence of chronic moderate-severe pain. Participants reported their pain to be longstanding: three-quarters of those with moderate or severe pain reported that their pain had lasted for 5 years or more.
Participants reported a high prevalence of pain interference, which suggests that, despite other barriers faced by homeless adults, pain plays a role in reducing self-efficacy and quality of life.Consistent with other research, we found an association between a personal history of victimization,arthritis, and PTSD symptoms with chronic pain.In contrast to other populations,we did not find an association between either substance use, number of chronic medical conditions, nor depression and chronic pain. Our study population experiences a higher burden of chronic disease, injuries, substance use, and mental health problems, than the general population. Despite a median age of 58, our participants had a higher prevalence of functional and cognitive impairments than the general population of older adults in their 70s and 80s.The high prevalence of these factors, as well as unique factors associated with homelessness may explain the high prevalence of chronic pain in our sample.Homeless adults experience harsh environmental conditions: approximately half spent almost all of their nights outdoors, without shelter. A significant minority spent many nights in group shelter situations, where individuals may sleep on floor mats or low quality mattresses. These conditions may contribute to the high prevalence of chronic pain. The lack of an association between substance use and chronic pain may be due to its overall high prevalence in our sample. We found that PTSD was more prevalent than in the general population and that it was associated with chronic pain. More than 40% of those who experienced chronic moderate to severe pain and more than 20% of those who did not, had likely PTSD, compared to approximately 8% of the general population.These prevalence ratios are similar to those found in other studies of homeless populations. PTSD is common in homeless populations, possibly due to a high prevalence of traumatic childhood experiences,pots for cannabis plants high prevalence of experiencing interpersonal violence, exposure to violence while homeless, coexisting psychiatric disorders, and poor social support.Unstable housing status may itself contribute to the development of PTSD.Existing research conceptualizes the relationships between chronic pain and PTSD to be one of mutual maintenance.Mutual maintenance asserts that mental health and substance use disorders maintain or worsen existing pain, while pain worsens these underlying conditions. The effective management of both pain and mental health problems should incorporate treatment of pain and behavioral health conditions simultaneously and longitudinally.We found a high prevalence of arthritis and a strong association between arthritis and chronic pain. In studies of primary care in the general population, older individuals are more likely than younger ones to attribute pain to arthritis. Approximately one-quarter of chronic pain in adults ≥55 years is attributed to arthritis.In a previous study of chronic pain in homeless adults of all ages, between 9% and 24% attributed their pain to arthritis.
Homeless older adults may have fewer evidence-based treatment options for arthritis pain than the general population, due to difficulties accessing regular medical care, low-impact exercise, and healthy food choices.Finally, our study found that victimization throughout the life course was associated with chronic pain. Similar associations were found in other populations.The increased recognition of the role of trauma in chronic pain and other clinical conditions has led to the development of “trauma informed care” as an approach to address patients’ experiences of trauma. Trauma informed care refers to the reorientation of systems of care to incorporate a fundamental understanding of the role that traumatic experiences play in the lives and symptoms of people seeking care. Although limited data exists as to its effectiveness, especially for the relief of somatic symptoms such as physical pain, data that do exist suggest that trauma informed care reduces PTSD and depressive symptoms.While the efficacy of opioid analgesics for the treatment of chronic non-cancer pain is questioned, their use for this condition remains widespread.While older adults may, counterintuitively, experience a lower risk of overdose than younger adults,10 the cooccurrence of substance use disorders and the chaotic conditions of homelessness limit the use of opioids in this population. While multiple consensus statements describe multidisciplinary care as the best approach for the management of chronic pain, limited data are available to support its efficacy.Most studies showed only a modest effect for a minority of participants with no or minimal benefits lasting after six months.Even if this care were efficacious, homeless individuals face numerous barriers to engaging in longitudinal care, including their need to prioritize food and housing, lack of insurance or financial resources, inadequate transportation, and inability to communicate with clinicians between visits.The health care of patients experiencing homelessness and the challenges of managing chronic pain are both foci of increasing research interest,yet chronic pain remains largely understudied among homeless adults. Homeless individuals face many barriers to research participation, and in particular, few studies focused on the emerging population of older homeless individuals. Most existing studies of homeless populations recruit either from health care facilities or homeless shelters, which may not be representative. By using population-based sampling and focusing on older homeless adults, our study provides the first estimates of chronic pain in a high-risk, but poorly understood, group of individuals. Our data demonstrate that chronic pain is not only common, but that it has detrimental effects on life enjoyment and general activity in older homeless adults. By decreasing functioning, chronic pain presents yet another hurdle for marginalized and under-resourced individuals to receive much needed health care and social services. In addition to causing physical and emotional distress, chronic pain can hamper individuals’ abilities to obtain and retain employment and stable housing, let alone to manage other health problems. This study has several limitations. The analysis is cross-sectional, so we cannot identify causality. Only 12% of the study participants are aged 65 or over, reflecting, in part, premature mortality among homeless adults. While homeless populations are considered “older” by age 50,13, 14 the study population is younger than most studies of older adults. Study participants’ poor access to health care may lead to under reporting of chronic health conditions, limiting our ability to find associations. Due to the stigma associated with victimization, participants may have under reported experiences of verbal, physical, or sexual abuse. This misclassification would limit our ability to find an association between abuse and chronic pain, so our results could be interpreted as conservative. We did not assess pain related diagnoses, such as back pain, sprains, strains, or fractures, or obtain participants’ understanding of the causes of their pain. We did not attain data on how they managed their pain or whether they had received treatment, including medication, for their pain.