Psychology

In this randomized clinical trial, we examined whether the effect of true acupuncture can be differentiated from sham acupuncture (pain and functionality) by analyzing quantitative sensory testing (QST) profiles in chronic pain participants. We recruited 254 healthy or chronic back and neck pain participants. Healthy subjects were included to control for a possible effect of acupuncture on baseline QST changes. Study participants received six sessions (twice weekly) of true acupuncture, sham acupuncture, or no acupuncture treatment (routine care). QST profiles, pain scores and functionality profile were obtained at baseline (visit 1) and after 3 (visit 4) or 6 sessions (visit 7). A total of 204 participants were analyzed. We found no QST profile changes among three groups (P = 0.533 and P = 0.549, Likelihood-ratio tests) in either healthy or chronic pain participants. In chronic back and neck pain participants, true acupuncture reduced pain [visit 4: DIM (difference in mean) = -0.8, 95% CI: -1.4 to -0.1, adjusted P = 0.168; visit 7: DIM = -1.0, 95% CI: -1.7 to -0.3, adjusted P = 0.021) and improved functional status including physical functioning (DIM = 14.21, 95% CI: 5.84 to 22.58, adjusted P = 0.003) and energy/fatigue (DIM = 12.28, 95% CI: 3.46 to 21.11, adjusted P = 0.021) as compared to routine care. Our results indicate that QST was not helpful to differentiate between true acupuncture and sham acupuncture (primary outcome) in this study, although true acupuncture reduced pain and improved functionality (secondary outcomes) when compared with routine care.

Fibromyalgia (FM) is a prevalent chronic pain disorder associated with large suffering and substantial societal costs. Pain-related avoidance behaviour and hypervigilance to bodily symptoms are common in FM and contribute in maintaining and exacerbating the disorder. Exposure therapy targeting avoidance behaviours and hypervigilance has shown promise in the treatment of FM. The present study investigated mediators of treatment outcome in exposure therapy for FM. We used data from a randomised trial, where 140 participants were allocated to 10-week internet-delivered exposure therapy or to a waiting-list control condition. The main outcome variable (FM symptoms) and the hypothesized mediators (FM-related avoidance behaviour, mindful non-reactivity and FM-related worry) were measured weekly throughout treatment. Mediation analyses were conducted using linear mixed effects models with bootstrap replication and time-lagged analysis. Results indicated that all three process variables were significant mediators of FM severity. However, in the time-lagged analyses, only FM-related avoidance behaviour displayed a unidirectional relationship over time with FM symptoms, suggesting a causal effect. Thus, results illustrate that changes in avoidance behaviour mediate the outcome of exposure on FM symptoms, which implies that avoidance behaviour is an important treatment target in exposure therapy.

Many recommended nonpharmacologic therapies for patients with chronic spinal pain require visits to providers such as acupuncturists and chiropractors. Little information is available to inform third-party payers' coverage policies regarding ongoing use of these therapies. This study offers contingent valuation-based estimates of patient willingness-to-pay (WTP) for pain reductions from a large (n=1583) sample of patients using ongoing chiropractic care to manage their chronic low-back and neck pain. Average WTP estimates were $45.98 (45.8) per month per 1-point reduction in current pain for chronic low-back pain and $37.32 (38.0) for chronic neck pain. These estimates met a variety of validity checks including that individuals' values define a downward-sloping demand curve for these services. Comparing these WTP estimates to patients' actual use of chiropractic care over the next 3 months indicates that these patients are likely "buying" perceived pain reductions from what they believe their pain would have been if they didn't see their chiropractor-i.e., they value maintenance of their current mild pain levels. These results provide some evidence for co-pay levels and their relationship to patient demand but call into question ongoing coverage policies that require documentation of continued improvement or of experienced clinical deterioration with treatment withdrawal. Perspective: This study provides estimates of reported willingness-to-pay for pain reduction from a large sample of patients using chiropractic care to manage their chronic spinal pain and compares these estimates to what these patients do for care over the next 3 months, to inform coverage policies for ongoing care.

Fibromyalgia syndrome (FM) represents a great challenge for clinicians and researchers because the efficacy of currently available treatments is limited. The present study examined the efficacy of Mindfulness-Based Stress Reduction (MBSR) for reducing functional impairment as well as the role of mindfulness-related constructs as mediators of treatment outcomes for people with FM. 225 participants with FM were randomized into three study arms: MBSR plus treatment-as-usual (TAU), FibroQoL (multicomponent intervention for FM) plus TAU, and TAU alone. The primary endpoint was functional impact (measured with the Fibromyalgia Impact Questionnaire Revised), and secondary outcomes included "fibromyalginess", anxiety and depression, pain catastrophising, perceived stress and cognitive dysfunction. The differences in outcomes between groups at post-treatment assessment (primary endpoint) and 12-month follow-up were analyzed using linear mixed-effects models and mediational models through path analyses. MBSR was superior to TAU both at post-treatment (large effect sizes) and at follow-up (medium to large effect sizes), and MBSR was also superior to FibroQoL post-treatment (medium to large effect sizes), but long-term it was only modestly better (significant differences only in pain catastrophising and fibromyalginess). Immediately post-treatment, the NNT for 20% improvement in MBSR versus TAU and FibroQoL was 4.0 (95%CI= 2.1-6.5) and 5.0 (95%CI= 2.7-37.3). An unreliable NNT value of 9 (not computable 95%CI) was found for FibroQoL vs. TAU. Changes produced by MBSR in functional impact were mediated by psychological inflexibility and the mindfulness facet Acting with awareness. These findings are discussed in relation to previous studies of psychological treatments for FM.

Comorbid psychiatric and pain-related conditions are common in patients with fibromyalgia. Most studies in this area have used data from patients in specialty care and may not represent the characteristics of fibromyalgia in primary care patients. We sought to fill gaps in the literature by determining if the association between psychiatric diagnoses, conditions associated with chronic pain, and fibromyalgia differed by gender in a primary care patient population.

Poor sleep quality has been associated with greater pain and fatigue in people living with osteoarthritis (OA). The objective of this micro-longitudinal study was to determine whether sleep impacts the diurnal pattern of next-day OA-related pain and fatigue. Community-dwelling older adults (≥65 years) with hip and/or knee OA provided data over 5 days using daily diaries and wrist-worn actigraphs. Pain and fatigue intensity were measured on awakening, at 11 am, 3 pm, 7 pm, and bedtime. Subjective previous night sleep quality was measured on awakening. Multilevel linear regression models examined interactions between sleep variables and time of next-day symptom reports. One hundred sixty participants provided 785 days of data (median age = 71 years; 62% female). Analysis of time interaction effects identified an association between poor sleep quality and more morning pain and fatigue. Although the effect on awakening was more pronounced for fatigue, differences in both symptoms attributable to sleep quality attenuated as the day progressed. Investigation of actigraphy-based sleep parameters revealed no significant interactions with time of symptom measurement. These findings observed in a sample of older adults with mild-to-moderate OA symptoms warrant further investigation in a sample with more severe symptoms and more pronounced sleep dysfunction and/or sleep disorders. PERSPECTIVE: This article investigates the impact of sleep on next-day pain and fatigue of older adults with OA. On awakening from a night of poor quality sleep, pain and fatigue intensity were heightened. However, the effect was not sustained throughout the day, suggesting the morning may be an optimal time for symptom interventions.