Pain, sleep and catastrophizing: The conceptualization matters: Comment on Wilt JA et al. "A multilevel path model analysis of the relations between sleep, pain, and pain catastrophizing in chronic pain rehabilitation patients"

Association of Sleep Disturbance With Catastrophizing and Knee Pain: Data From the Osteoarthritis Initiative

OBJECTIVE

To investigate the relationship between sleep disturbance, catastrophizing, and knee pain in middle-aged and older individuals.

METHODS

Data from the Osteoarthritis Initiative cohort from months 48 to 96 were used, where month 48 was treated as baseline. Knee pain (Western Ontario and McMaster Universities Osteoarthritis Index pain scale score ≥5 [range 0-20]), catastrophizing (extracted from Coping Strategies Questionnaire score ≥3 [range 0-6]), and sleep quality (extracted from Center for Epidemiologic Studies Depression Scale [range 1-4]) were assessed annually. We described the association of sleep disturbance with the presence and risk of knee pain and catastrophizing. The mediation effect of knee pain and catastrophizing on the sleep-catastrophizing and sleep-pain association was evaluated, respectively.

RESULTS

Catastrophizing and knee pain were reported in 346 (10%) and 917 (24%) of the 3,813 participants (mean 64.9 years, 58% female) at baseline. Participants with worse sleep disturbance were more likely to have knee pain (prevalence ratio [PR] 1.4-2.0, P for trend <0.001) and catastrophizing (PR 1.4-3.1, P for trend <0.001). Sleep disturbance at baseline predicted the risk of knee pain (risk ratio [RR] 1.1, P for trend <0.001) and catastrophizing (RR 1.2-1.7, P for trend <0.001) during follow-up. No statistically significant interactions between sleep disturbance and knee pain or catastrophizing were observed. Knee pain and catastrophizing mediated the sleep-catastrophizing and sleep-pain association, respectively, at baseline, and knee pain negatively mediated the sleep-catastrophizing association longitudinally.

CONCLUSION

Sleep disturbance was associated with the presence and risk of catastrophizing and knee pain. Sleep interventions may have a universal and independent effect in preventing incident knee pain.

Associations Among Sleep Disturbance, Pain Catastrophizing, and Pain Intensity for Methadone-maintained Patients With Opioid Use Disorder and Chronic Pain

OBJECTIVE

This study examined the cross-sectional associations among pain intensity, pain catastrophizing, and sleep disturbance among patients receiving methadone maintenance treatment (MMT) for opioid use disorder (OUD) and reporting co-occurring chronic pain.

MATERIALS AND METHODS

Participants were 89 individuals with OUD and chronic pain drawn from a larger cross-sectional study of 164 MMT patients who completed a battery of self-report measures. The authors conducted 6 mediation models to test all possible pathways (ie, each variable tested as an independent variable, mediator, or dependent variable).

RESULTS

The only significant mediation effect was an indirect effect of sleep disturbance on pain intensity through pain catastrophizing. That is, greater sleep disturbance was associated with greater pain catastrophizing, which in turn was associated with greater pain intensity.

DISCUSSION

Altogether, findings suggest that the sleep disturbance to pain catastrophizing to pain intensity pathway may be a key mechanistic pathway exacerbating pain issues among MMT patients with OUD and chronic pain. These results suggest that interventions targeting sleep disturbance may be warranted among MMT patients with OUD and chronic pain. Future work in this area with longitudinal data is warranted.

Predicting Responses to Pregabalin for Painful Diabetic Peripheral Neuropathy Based on Trajectory-Focused Patient Profiles Derived from the First 4 Weeks of Treatment

INTRODUCTION

Prediction of final clinical outcomes based on early weeks of treatment can enable more effective patient care for chronic pain. Our goal was to predict, with at least 90% accuracy, 12- to 13-week outcomes for pregabalin-treated painful diabetic peripheral neuropathy (pDPN) patients based on 4 weeks of pain and pain-related sleep interference data.

METHODS

We utilized active treatment data from six placebo-controlled randomized controlled trials (n = 939) designed to evaluate efficacy of pregabalin for reducing pain in patients with pDPN. We implemented a three-step, trajectory-focused analytics approach based upon patient responses collected during the first 4 weeks using monotonicity, path length, frequency domain (FD), and k-nearest neighbor (kNN) methods. The first two steps were based on combinations of baseline pain, pain at 4 weeks, weekly monotonicity and path length during the first 4 weeks, and assignment of patients to one of four responder groups (based on presence/absence of 50% or 30% reduction from baseline pain at 4 and at 12/13 weeks). The third step included agreement between prediction of logistic regression of daily FD amplitudes and assignment made from kNN analyses.

RESULTS

Step 1 correctly assigned 520/939 patients from the six studies to a responder group using a 3-metric combination approach based on unique assignment to a 50% responder group. Step 2 (applied to the remaining 419 patients) predicted an additional 121 patients, using a blend of 50% and 30% responder thresholds. Step 3 (using a combination of FD and kNN analyses) predicted 204 of the remaining 298 patients using the 50% responder threshold. Our approach correctly predicted 90.0% of all patients.

CONCLUSION

By correctly predicting 12- to 13-week responder outcomes with 90% accuracy based on responses from the first month of treatment, we demonstrated the value of trajectory measures in predicting pDPN patient response to pregabalin.

TRIAL REGISTRATION

www.clinicaltrials.gov identifiers, NCT00156078/NCT00159679/NCT00143156/NCT00553475.

FUNDING

Pfizer. Plain language summary available for this article.