Comparative Responsiveness of Pain Measures in Cancer Patients

Brief measures to assess and monitor pain in cancer patients are available, but few head-to-head psychometric comparisons of different measures have been reported. Baseline and 3-month data were analyzed from 274 patients enrolled in the Indiana Cancer Pain and Depression (INCPAD) trial. Participants completed the Brief Pain Inventory (BPI), the PEG (a 3-item abbreviated version of the BPI), the short form (SF)-36 pain scale, and a pain global rating of change measure. The global rating was used as the criterion for standardized response mean and receiver operating characteristic curve analyses. To assess responsiveness to the trial intervention, we evaluated standardized effect size statistics stratified by trial arm. All measures were responsive to global improvement, discriminated between participants with and without improvement, and detected a significant intervention treatment effect. Short and longer measures were similarly responsive. Also, composite measures that combined pain severity and interference into a single score (BPI total, PEG, SF-36 pain) performed comparably to separate measures of each domain (BPI severity and BPI interference)

“I was a little surprised”: Qualitative Insights from Patients Enrolled in a 12-Month Trial Comparing Opioids to Non-Opioid Medications for Chronic Musculoskeletal Pain

Chronic musculoskeletal pain is a major public health problem. Although opioid prescribing for chronic pain has increased dramatically since the 1990s, this practice has come under scrutiny because of increases in opioid-related harms and lack of evidence for long-term effectiveness. The Strategies for Prescribing Analgesics Comparative Effectiveness (SPACE) trial was a pragmatic 12-month randomized trial comparing benefits and harms of opioid versus non-opioid medications for chronic musculoskeletal pain. The current qualitative study was designed to better understand trial results by exploring patients’ experiences, including perceptions of medications, experiences with the intervention, and whether expectations were met. Thirty-four participants who were purposefully sampled based on treatment group and intervention response participated in semi-structured interviews. The constant comparison method guided analysis. Results revealed that participants often held strong beliefs about opioid medications, which sometimes changed during the trial as they gained experience with medications; participants described a wide variety of experiences with treatment effectiveness, regardless of study group or their response to the intervention; and participants highly valued the personalized pain care model used in SPACE

Does comorbid chronic pain affect posttraumatic stress disorder diagnosis and treatment? Outcomes of posttraumatic stress disorder screening in Department of Veterans Affairs primary care

Because posttraumatic stress disorder (PTSD) is both prevalent and underrecognized, routine primary care-based screening for PTSD has been implemented across the Veterans Health Administration. PTSD is frequently complicated by the presence of comorbid chronic pain, and patients with both conditions have increased symptom severity and poorer prognosis. Our objective was to determine whether the presence of pain affects diagnosis and treatment of PTSD among Department of Veterans Affairs (VA) patients who have a positive PTSD screening test. This retrospective cohort study used clinical and administrative data from six Midwestern VA medical centers. We identified 4,244 VA primary care patients with a positive PTSD screen and compared outcomes for those with and without a coexisting pain diagnosis. Outcomes were three clinically appropriate responses to positive PTSD screening: (1) mental health visit, (2) PTSD diagnosis, and (3) new selective serotonin reuptake inhibitor (SSRI) prescription. We found that patients with coexisting pain had a lower rate of mental health visits than those without pain (hazard ratio: 0.889, 95% confidence interval: 0.821–0.962). There were no significant differences in the rate of PTSD diagnosis or new SSRI prescription between patients with and without coexisting pain

Comparative Responsiveness of the PROMIS Pain Interference Short Forms, Brief Pain Inventory, PEG, and SF-36 Bodily Pain Subscale

PURPOSE: To compare the sensitivity to change and the responsiveness to intervention of the PROMIS Pain Interference short forms, Brief Pain Inventory (BPI), 3-item PEG scale, and SF-36 Bodily Pain subscale in a sample of patients with persistent musculoskeletal pain of moderate severity. METHODS: Standardized response means, standardized effect sizes, and receiver operating curve analyses were used to assess change between baseline and 3-month assessments in 250 participants who participated in a randomized clinical effectiveness trial of collaborative telecare management for moderate to severe and persistent musculoskeletal pain. RESULTS: The BPI, PEG, and SF-36 Bodily Pain measures were more sensitive to patient-reported global change than the PROMIS Pain Interference short forms, especially for the clinically improved group, for which the change detected by the PROMIS short forms was not statistically significant. The BPI was more responsive to the clinical intervention than the SF-36 Bodily Pain and PROMIS Pain Interference measures. Post hoc analyses exploring these findings did not suggest that differences in content or rating scale structure (number of response options or anchoring language) adequately explained the observed differences in the detection of change. CONCLUSIONS: In this clinical trial, the BPI and PEG measures were better able to detect change than the SF-36 Bodily Pain and PROMIS Pain Interference measures

Comparative responsiveness of pain outcome measures among primary care patients with musculoskeletal pain

BACKGROUND: Comparative responsiveness data are needed to inform choices about pain outcome measures. OBJECTIVES: To compare responsiveness of pain intensity, pain-related function, and composite measures, using data from a randomized trial and observational study. RESEARCH DESIGN: Analysis of responsiveness. SUBJECTS: A total of 427 adults with persistent back, hip, or knee pain were recruited from primary care. METHODS: Participants completed Brief Pain Inventory, Chronic Pain Grade (CPG), Roland disability, SF-36 bodily pain, and pain global rating of change measures. We used the global rating as the anchor for standardized response mean and receiver operating characteristic curve analyses. We used the distribution-based standard error of measurement to estimate minimally important change. To assess responsiveness to the trial intervention, we evaluated standardized effect size statistics stratified by trial arm. RESULTS: All measures were responsive to global improvement and all had fair-to-good accuracy in discriminating between participants with and without improvement. SF bodily pain was less responsive than other measures in several analyses. The 3-item PEG was similarly responsive to full Brief Pain Inventory scales. CPG and SF bodily pain were less responsive to the trial intervention and did not perform well among participants with hip/knee pain. Agreement between anchor and distribution-based methods was modest. CONCLUSIONS: If a brief measure is desired, the 3-item PEG is more responsive than the SF bodily pain scale. CPG and SF bodily pain scales may be relatively poor choices for trial outcome assessment. Both anchor and distribution-based methods should be considered when determining clinically important change

Opioid Use as a Predictor of Health Care Use and Pain Outcomes: Analysis of Clinical Trial Data

Objective . To examine effects of pre-enrollment opioid use on outcomes of a 12-month collaborative pain care management trial. We hypothesized that participants with opioid use would have worse pain at baseline; use more health care services and analgesics; and have worse pain outcomes during the trial. Design . Secondary analysis of randomized controlled trial data. Setting . Veterans Affairs (VA) primary care. Subjects . Patients age 18-65 years with chronic pain of at least moderate severity who were enrolled in a 12-month pragmatic trial of a telephone-based collaborative care intervention for chronic musculoskeletal pain. Methods . Participants were categorized as opioid users (n = 84) or non-users (n = 166) at baseline and trial randomization was stratified by opioid use. We used logistic regression to examine cross-sectional associations with baseline opioid use and mixed-effect models for repeated measures to examine baseline opioid use as a predictor of Brief Pain Inventory (BPI) scores over 12 months. Results . At baseline, 33.6% reported use of prescribed opioids. Baseline opioid users had higher baseline BPI scores and higher health-related disability than non-users. Baseline opioid users also had more outpatient visits (15.0 vs. 10.1; p = 0.001) and received more analgesics (p < 0.001) during the trial. In the final multivariable model examining effects of baseline opioid use on BPI over 12 months, opioid users and nonusers had a non-significant difference of 0.25 points (p = 0.098). In conclusion, although baseline opioid users had worse pain at baseline and used more health care during the study, response to the intervention was not significantly modified by pre-existing opioid therapy

Comparative Responsiveness of the PROMIS Pain Interference Short Forms with Legacy Pain Measures: Results from Three Randomized Clinical Trials

The PROMIS Pain Interference (PROMIS-PI) scales are reliable and publicly accessible; however, little is known about how responsive they are to detect change in clinical trials and how their responsiveness compares to legacy measures. The study purpose was to evaluate responsiveness for the PROMIS-PI scales and to compare their responsiveness with legacy pain measures. We used data from three clinical trials totaling 759 participants. The clinical trials included patients with chronic low back pain (n= 261), chronic back or osteoarthritis pain (n = 240), and a history of stroke (n= 258). At both baseline and follow-up, participants completed PROMIS-PI scales and legacy pain measures (Brief Pain Inventory Interference scale, Pain/Enjoyment/General Activity (PEG) scale, SF-36 Bodily Pain scale, and Roland-Morris Disability Questionnaire). We measured global ratings of pain change, both prospectively and retrospectively, as anchors to identify patients as improved, unchanged, or worsened. Responsiveness was assessed with standardized response means, statistical tests comparing change groups, and area-under-curve analysis. The PROMIS-PI scales had largely comparable responsiveness with the Brief Pain Inventory Interference scale and PEG. The four PROMIS-PI short forms had comparable responsiveness. For all pain questionnaires, responsiveness varied based on the study population and whether pain improved or worsened

Effect of Opioid vs Nonopioid Medications on Pain-Related Function in Patients With Chronic Back Pain or Hip or Knee Osteoarthritis Pain

Importance: Limited evidence is available regarding long-term outcomes of opioids compared with nonopioid medications for chronic pain. Objective: To compare opioid vs nonopioid medications over 12 months on pain-related function, pain intensity, and adverse effects. Design, Setting, and Participants: Pragmatic, 12-month, randomized trial with masked outcome assessment. Patients were recruited from Veterans Affairs primary care clinics from June 2013 through December 2015; follow-up was completed December 2016. Eligible patients had moderate to severe chronic back pain or hip or knee osteoarthritis pain despite analgesic use. Of 265 patients enrolled, 25 withdrew prior to randomization and 240 were randomized. Interventions: Both interventions (opioid and nonopioid medication therapy) followed a treat-to-target strategy aiming for improved pain and function. Each intervention had its own prescribing strategy that included multiple medication options in 3 steps. In the opioid group, the first step was immediate-release morphine, oxycodone, or hydrocodone/acetaminophen. For the nonopioid group, the first step was acetaminophen (paracetamol) or a nonsteroidal anti-inflammatory drug. Medications were changed, added, or adjusted within the assigned treatment group according to individual patient response. Main Outcomes and Measures: The primary outcome was pain-related function (Brief Pain Inventory [BPI] interference scale) over 12 months and the main secondary outcome was pain intensity (BPI severity scale). For both BPI scales (range, 0-10; higher scores = worse function or pain intensity), a 1-point improvement was clinically important. The primary adverse outcome was medication-related symptoms (patient-reported checklist; range, 0-19). Results: Among 240 randomized patients (mean age, 58.3 years; women, 32 [13.0%]), 234 (97.5%) completed the trial. Groups did not significantly differ on pain-related function over 12 months (overall P = .58); mean 12-month BPI interference was 3.4 for the opioid group and 3.3 for the nonopioid group (difference, 0.1 [95% CI, -0.5 to 0.7]). Pain intensity was significantly better in the nonopioid group over 12 months (overall P = .03); mean 12-month BPI severity was 4.0 for the opioid group and 3.5 for the nonopioid group (difference, 0.5 [95% CI, 0.0 to 1.0]). Adverse medication-related symptoms were significantly more common in the opioid group over 12 months (overall P = .03); mean medication-related symptoms at 12 months were 1.8 in the opioid group and 0.9 in the nonopioid group (difference, 0.9 [95% CI, 0.3 to 1.5]). Conclusions and Relevance: Treatment with opioids was not superior to treatment with nonopioid medications for improving pain-related function over 12 months. Results do not support initiation of opioid therapy for moderate to severe chronic back pain or hip or knee osteoarthritis pain

Design, recruitment outcomes, and sample characteristics of the Strategies for Prescribing Analgesics Comparative Effectiveness (SPACE) trial

This manuscript describes the study protocol, recruitment outcomes, and baseline participant characteristics for the Strategies for Prescribing Analgesics Comparative Effectiveness (SPACE) trial. SPACE is a pragmatic randomized comparative effectiveness trial conducted in multiple VA primary care clinics within one VA health care system. The objective was to compare benefits and harms of opioid therapy versus non-opioid medication therapy over 12 months among patients with moderate-to-severe chronic back pain or hip/knee osteoarthritis pain despite analgesic therapy; patients already receiving regular opioid therapy were excluded. Key design features include comparing two clinically-relevant medication interventions, pragmatic eligibility criteria, and flexible treat-to-target interventions. Screening, recruitment and study enrollment were conducted over 31 months. A total of 4491 patients were contacted for eligibility screening; 53.1% were ineligible, 41.0% refused, and 5.9% enrolled. The most common reasons for ineligibility were not meeting pain location and severity criteria. The most common study-specific reasons for refusal were preference for no opioid use and preference for no pain medications. Of 265 enrolled patients, 25 withdrew before randomization. Of 240 randomized patients, 87.9% were male, 84.1% were white, and age range was 21–80 years. Past-year mental health diagnoses were 28.3% depression, 17% anxiety, 9.4% PTSD, 7.9% alcohol use disorder, and 2.6% drug use disorder. In conclusion, although recruitment for this trial was challenging, characteristics of enrolled participants suggest we were successful in recruiting patients similar to those prescribed opioid therapy in usual care

Estimating minimally important differences for the PROMIS pain interference scales: results from 3 randomized clinical trials

Minimally important difference (MID) refers to the smallest meaningful difference that carries implications for patient care. Minimally important differences are necessary to help interpret patient-reported pain outcomes in research and clinical practice. The PROMIS pain interference scales were validated across diverse samples; however, more information about their MIDs could improve their interpretability. The purpose of this study was to estimate MIDs for 4 fixed-length PROMIS pain interference scales, including the 6-item Pain Short Form and the 4-, 6-, and 8-item pain interference scales used in the PROMIS profile instruments. Data were analyzed from 3 randomized controlled trials (N = 759). The 3 samples, respectively, consisted of patients with chronic low back pain (n = 261), chronic back pain or hip/knee osteoarthritis pain (n = 240), and a history of stroke (n = 258). For each sample, anchor- and distribution-based approaches were used to estimate MIDs. Standard error of measurement and effect sizes were used as distribution-based MID estimates. Anchor-based MID estimates were established by mapping PROMIS pain interference scores onto established anchor measures, including the Brief Pain Inventory, and retrospective and prospective global ratings of change. The distribution- and anchor-based MID estimates showed convergence. For the pain samples, MID estimates ranged from 2 to 3 T-score points. For the nonpain sample, MID estimates ranged from 3.5 to 4.5 T-score points. The MID estimates were comparable across the 4 fixed-length scales. These MIDs can be used to evaluate treatment effects in research and clinical care and to calculate estimates for powering clinical trials