Pain
-
Spinal cord stimulation (SCS) is an interventional nonpharmacologic treatment used for chronic pain and other indications. Methods for evaluating the safety and efficacy of SCS have evolved from uncontrolled and retrospective studies to prospective randomized controlled trials (RCTs). ⋯ This article summarizes the results of this meeting. Highlights of our recommendations include disclosing all funding source and potential conflicts; incorporating mechanistic objectives when possible; avoiding noninferiority designs without internal demonstration of assay sensitivity; achieving and documenting double-blinding whenever possible; documenting investigator and site experience; keeping all information provided to patients balanced with respect to expectation of benefit; disclosing all information provided to patients, including verbal scripts; using placebo/sham controls when possible; capturing a complete set of outcome assessments; accounting for ancillary pharmacologic and nonpharmacologic treatments in a clear manner; providing a complete description of intended and actual programming interactions; making a prospective ascertainment of SCS-specific safety outcomes; training patients and researchers on appropriate expectations, outcome assessments, and other key aspects of study performance; and providing transparent and complete reporting of results according to applicable reporting guidelines.
-
The International Classification of Diseases-11 (ICD-11) chronic pain classification includes about 100 chronic pain diagnoses on different diagnostic levels. Each of these diagnoses requires specific operationalized diagnostic criteria to be present. The classification comprises more than 200 diagnostic criteria. ⋯ The results of the pilot evaluation showed good clinical utility of the algorithm. The CAL-CP can contribute to reliable diagnoses by structuring a way through the classification and by increasing adherence to the criteria. Future studies need to evaluate its utility further and analyze its impact on the accuracy of the assigned diagnoses.
-
The current study used data from a clinical trial to identify variables that are associated with and/or mediate the beneficial effects of 4 psychological chronic pain treatments: one teaching patients self-hypnosis to reduce pain intensity (HYP), one teaching self-hypnosis to change thoughts about pain (hypnotic cognitive therapy [HYP-CT]), one teaching cognitive restructuring skills to change thoughts about pain (cognitive therapy [CT]), and one providing education about pain (ED; included as an active control condition). Of 17 possible mechanism variables examined, and with alpha not corrected for multiple comparisons, significant between-group differences were observed for 3. Two of these (changes in beliefs about control over pain and number of days of skill practice) were supported as mediators of the beneficial effects of HYP, CT, or HYP-CT, relative to ED. ⋯ In addition, participant ratings of therapeutic alliance at post-treatment were associated significantly with improvements in both pain intensity and pain interference in the sample as a whole. Thus, of the 17 possible mediators examined, there were relatively few that served as mediators for the beneficial effects of specific treatments; a larger number of variables predicted treatment outcome overall. The extent to which these variables are treatment mediators (ie, are responsible for, rather than merely associated with, treatment-related improvements) will require further research.
-
Primary dysmenorrhea (PDM) is not only a painful experience but also affects the psychological and affective states of women. Neuroimaging studies have revealed shared neural substrates for somatic and empathic pains in healthy subjects. However, little is known about the relationship between pain intensity and pain empathy in pain disorders. ⋯ The anterior insula and brain regions related to sensory discrimination with decreased gray matter volumes were not only shared but also acted as a mediator between pain intensity and pain empathy in PDM patients. In addition, the general linear modeling analysis revealed that long-term pain experience was a more important factor to pain empathy compared with pain intensity. This indicated that long-term pain may cause maladaptive brain structural plasticity, which may further affect psychological adjustment to bring patients more vivid pain when they witness suffering and distress in others.
-
A large body of evidence indicates how pain affects motor control, yet the way the motor system influences pain perception remains unclear. We present 2 experiments that investigated sensory attenuation of pain implementing a 2-alternative forced choice paradigm. Particularly, healthy participants received painful stimuli on a moving and nonmoving hand during the execution or the preparation of reaching motor actions. ⋯ Together these findings indicate that executing, but not preparing, a motor action affects pain processing in that body part. No significant associations were found between sensory attenuation indices and inhibitory control abilities or pain catastrophizing, vigilance and rumination. These results provide insight into the inhibitory effects of motor actions on pain processing, suggesting that pain perception is a dynamic experience susceptible to individuals' actions in the environment.