Pain
-
Multicenter Study
Elevated levels of gonadotrophins but not sex steroids are associated with musculoskeletal pain in middle-aged and older European men.
The aim of this study was to determine the association of hormone levels with the occurrence of musculoskeletal pain. Men ages 40 to 79 years were recruited from population registers in 8 European centres. Subjects were asked to complete a postal questionnaire, which enquired about lifestyle and the occurrence of musculoskeletal pain over the past month. ⋯ Compared with those in the lowest tertile of LH, those in the highest tertile were more likely to report some pain (vs no pain, RRR=1.28; 95% CI 1.09 to 1.50) and also CWP (vs no pain, RRR=1.51; 95% CI 1.10 to 2.07). Similar results were found for FSH. Gonadotrophins, but not sex steroid hormone levels, are associated with musculoskeletal pain in men.
-
For most healthy subjects, both subjective pain ratings and pain-evoked potentials are attenuated under conditioned pain modulation (CPM; formerly termed diffuse noxious inhibitory controls, or DNIC). Although essentially spinal-bulbar, this inhibition is under cortical control. This is the first study to observe temporal as well as spatial changes in cortical activations under CPM. ⋯ This was followed by reduced activations in the primary and secondary somatosensory cortices, supplementary motor area, posterior insula, and anterior cingulate cortex from 400 ms poststimulus. Our findings show that the prefrontal pain-controlling areas of OFC and amygdala increase their activity in parallel with subjective pain reduction under CPM, and that this increased activity occurs prior to reductions in activations of the pain sensory areas. In conclusion, achieving pain inhibition by the CPM process seems to be under control of the OFC and the amygdala.
-
Randomized Controlled Trial
Induction of nocebo and placebo effects on itch and pain by verbal suggestions.
Physical complaints, such as pain, can be effectively reduced by placebo effects through induction of positive expectations, or increased by nocebo effects through induction of negative expectations. In the present study, verbally induced nocebo and placebo effects on itch were experimentally investigated for the first time. In part 1, the role of verbal suggestions in inducing nocebo effects on itch and pain was investigated. ⋯ In part 2, verbal suggestions designed to produce a placebo effect on itch (itch placebo) or pain (pain placebo), or neutral suggestions (itch placebo control and pain placebo control) were given regarding a second application of histamine and compared with the first application applied in part 1. Results of placebo effects only showed a significantly larger decrease in itch in the itch placebo condition than in the pain placebo condition. In conclusion, we showed for the first time that nocebo and possibly placebo responses can be induced on itch by verbal suggestions.
-
The current study examined the relationship between pain-related fear, physical performance, and pain-related interference in the context of experimentally induced pain to the lower back. Thirty healthy participants completed a test of maximal trunk strength before and after induction of delayed-onset muscle soreness (DOMS) to the trunk extensors. Pain-related fear (Tampa Scale of Kinesiophobia and Pain Anxiety Symptom Scale) was assessed prior to DOMS induction, and measures of current pain and pain-related interference with life activities were obtained 1 day after DOMS induction. ⋯ Current pain intensity and anthropometric factors did not contribute significantly to these outcome measures. To our knowledge, this is the first study to identify the impact of pain-related fear on physical performance among a healthy group of individuals following experimental acute low back injury. The findings extend previous research on psychological variables and simulated injury, and suggest that pain-related fear may be an important vulnerability factor in development of disability following acute pain experience.