Pain
-
Randomized Controlled Trial
The association of acetazolamide infusion with headache and cranial artery dilation in healthy volunteers.
The carbonic anhydrase inhibitor acetazolamide causes extracellular acidosis and dilatation of cerebral arterioles. In this study, we tested the hypothesis that acetazolamide also may induce headache and dilatation of cranial arteries. In a randomized double-blind crossover study design, 12 young healthy women were allocated to injection of 1 g acetazolamide or placebo on 2 separate days. ⋯ Compared to placebo, arterial circumference increased after acetazolamide in the basilar artery (P=.002) as well as the cerebral (P=.003), cavernous (P=.002), and cervical (P=.005) parts of the internal carotid artery, but no other extracranial arteries changed after acetazolamide. In conclusion, acetazolamide caused immediate and delayed headache as well as dilatation of intracranial arteries in healthy volunteers. It is possible that extracellular acidosis induced by acetazolamide causes sensitization of cephalic perivascular nociceptors, which, in combination with vasodilatation, leads to delayed headache.
-
Randomized Controlled Trial
Short-term Improvement in Insomnia Symptoms Predicts Long-term Improvements in Sleep, Pain, and Fatigue in Older Adults with Co-Morbid Osteoarthritis and Insomnia.
In a primary care population of 367 older adults (aged ⩾60 years) with osteoarthritis (OA) pain and insomnia, we examined the relationship between short-term improvement in sleep and long-term sleep, pain, and fatigue outcomes through secondary analyses of randomized controlled trial data. Study participants, regardless of experimental treatment received, were classified either as improvers (⩾30% baseline to 2-month reduction on the Insomnia Severity Index [ISI]) or as nonimprovers. After controlling for treatment arm and potential confounders, improvers showed significant, sustained improvements across 18 months compared with nonimprovers in pain severity (P<0.001, adjusted mean difference=-0.51 [95% CI: -0.80, -0.21), arthritis symptoms (P<0.001, 0.63 [0.26, 1.00]), and fear avoidance (P=0.009, -2.27 [-3.95, -0.58]) but not in catastrophizing or depression. Improvers also showed significant, sustained improvements in ISI (P<0.001, -3.03 [-3.74, -2.32]), Pittsburgh Sleep Quality Index Total (P<0.001, -1.45 [-1.97, -0.93]) and general sleep quality (P<0.001, -0.28 [-0.39, -0.16]) scores, Flinders Fatigue Scale (P<0.001, -1.99 [-3.01, -0.98]), and Dysfunctional Beliefs About Sleep Scale (P=0.037, -2.44 [-4.74, -0.15]), but no improvements on the Functional Outcomes of Sleep Questionnaire or the Epworth Sleepiness Scale. We conclude that short-term (2-month) improvements in sleep predicted long-term (9- and 18-month) improvements for multiple measures of sleep, chronic pain, and fatigue. These improvements were not attributable to nonspecific benefits for psychological well-being, such as reduced depression. These findings are consistent with benefits of improved sleep for chronic pain and fatigue among older persons with osteoarthritis pain and comorbid insomnia if robust improvements in sleep are achieved and sustained.
-
Randomized Controlled Trial
The emotion regulatory function of parent attention to child pain and associated implications for parental pain control behaviour.
We investigated the function of parental attention to child pain in regulating parental distress and pain control behaviour when observing their child performing a painful (cold pressor) task (CPT); we also studied the moderating role of parental state anxiety. Participants were 62 schoolchildren and one of their parents. Parental attention towards or away from child pain (ie, attend to pain vs avoid pain) was experimentally manipulated during a viewing task pairing unfamiliar children's neutral and pain faces. ⋯ Specifically, whereas low anxious parents reported more distress and demonstrated more pain control behaviour in the Attend to Pain condition, high anxious parents reported more distress and showed more pain control behaviour in the Avoid Pain condition. This inverse pattern was likewise apparent in physiological distress indices (HR) in response to the initial viewing task. Theoretical/clinical implications and further research directions are discussed.
-
Randomized Controlled Trial
Interdisciplinary Rehabilitation of Patients with Chronic Widespread Pain: Primary Endpoint of the Randomized, Non-Blinded, Parallel-Group IMPROvE Trial.
This study examined the functional and psychological outcomes of a 2-week, group-based multicomponent treatment course that targeted patients with chronic widespread pain. Patients (192 included in the intention-to-treat population), all fulfilling the 1990 American College of Rheumatology classification criteria for fibromyalgia, were consecutively recruited from a tertiary care setting and randomized (1:1) to either the treatment course or a waiting list control group. Co-primary outcomes were the Assessment of Motor and Process Skills (AMPS) and SF-36 Mental Composite Score (MCS) evaluated at 6-month follow-up. ⋯ We conclude that even in fibromyalgia patients presenting with a substantial disability established over many years, the 2-week multicomponent treatment course resulted in observable improvement of functional ability in a subgroup of patients at 6-month follow-up. This improvement, however, was not reflected in secondary patient reported outcomes, including scores of self-reported functional ability on standardized questionnaires. We suggest including observation-based assessments in future clinical trials focusing on functional outcomes in patients with fibromyalgia.
-
Randomized Controlled Trial
Identifying Treatment Responders and Predictors of Improvement after Cognitive-Behavioral Therapy for Juvenile Fibromyalgia.
The primary objective of this study was to estimate a clinically significant and quantifiable change in functional disability to identify treatment responders in a clinical trial of cognitive-behavioral therapy (CBT) for youth with juvenile fibromyalgia (JFM). The second objective was to examine whether baseline functional disability (Functional Disability Inventory), pain intensity, depressive symptoms (Children's Depression Inventory), coping self-efficacy (Pain Coping Questionnaire), and parental pain history predicted treatment response in disability at 6-month follow-up. Participants were 100 adolescents (11-18 years of age) with JFM enrolled in a recently published clinical trial comparing CBT to a fibromyalgia education (FE) intervention. ⋯ For CBT, patients with greater initial disability and higher coping efficacy were significantly more likely to achieve a clinically significant improvement in functioning. Pain intensity, depressive symptoms, and parent pain history did not significantly predict treatment response. Estimating clinically significant change for outcome measures in behavioral trials sets a high bar but is a potentially valuable approach to improve the quality of clinical trials, to enhance interpretability of treatment effects, and to challenge researchers to develop more potent and tailored interventions.