Pain Reports最新文献

{"title":"Severe acute respiratory syndrome coronavirus 2 infection altered the factors associated with headache: evidence from a multicenter community-based case-control study.","authors":"Mohammad Ali","doi":"10.1097/PR9.0000000000001051","DOIUrl":"https://doi.org/10.1097/PR9.0000000000001051","url":null,"abstract":"<p><strong>Introduction: </strong>Headache is one of the significant global public health concerns. Furthermore, it is a standard feature of patients with acute and postacute COVID-19.</p><p><strong>Objectives: </strong>This study aimed to estimate and compare the prevalence of headaches among postacute COVID and non-COVID individuals and identify and contrast the risk factors between both groups.</p><p><strong>Methods: </strong>This was a multicenter case-control study. Individuals who had recovered from acute SARS-CoV-2 infection were considered \"case\", and those who never tested positive for COVID-19 were considered \"control.\" Headaches were measured using the musculoskeletal subscale of the subjective health complaints scale. Multiple logistic regression analysis was used to identify the predictors of headaches.</p><p><strong>Results: </strong>A total of 878 individuals (439 cases) aged 38.30 ± 12.77 years (mean ± standard deviation) participated in this study. The prevalence of headaches was 26.2% among COVID-19 survivors; however, only 10.7% of unaffected participants reported headaches at the same time. Regression analyses suggested that the recovery duration from acute COVID-19 ≤ 90 days (adjusted odds ratio [AOR] = 2.03, CI = 1.13-3.65) was the only predictor of headache among postacute COVID-19 survivors. However, the female gender (AOR = 3.09, 95% CI = 1.51-6.32), members of a joint family (AOR = 1.99, 95% CI = 1.02-3.90), and city dwellers (AOR = 2.43, 95% CI = 0.94-6.25) were the predictor of headache among non-COVID participants.</p><p><strong>Conclusion: </strong>This study found a higher prevalence of headaches among COVID-19 survivors. In addition, predictors of headache among cases and controls were unmatched, indicating heterogenous impact of COVID-19 on human health. The health care providers should be informed of the study's results when discussing better practices to mitigate the burden of headaches.</p>","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/14/3a/painreports-7-e1051.PMC9699507.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40491638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A literature review of the impact of exclusion criteria on generalizability of clinical trial findings to patients with chronic pain.","authors":"Vafi Salmasi, Theresa R Lii, Keith Humphreys, Vinay Reddy, Sean C Mackey","doi":"10.1097/PR9.0000000000001050","DOIUrl":"10.1097/PR9.0000000000001050","url":null,"abstract":"<p><p>The ability of clinical trials to inform the care of chronic pain may be limited if only an unrepresentative subset of patients are allowed to enroll. We summarize and report new insights on published studies that report on how trial exclusions affect the generalizability of their results. We conducted a PubMed search on the following terms: ((\"eligibility criteria\" AND generalizability) OR (\"exclusion criteria\" AND generalizability) OR \"exclusion criteria\"[ti] OR \"eligibility criteria\"[ti]) AND pain. We only considered studies relevant if they analyzed data on (1) the prevalence and nature of exclusion criteria or (2) the impact of exclusion criteria on sample representativeness or study results. The 4 articles that were identified reported differences in patients who were included and excluded in different clinical trials: excluded patients were older, less likely to have a paid job, had more functional limitations at baseline, and used strong opioids more often. The clinical significance of these differences remains unclear. The pain medicine literature has very few published studies on the prevalence and impact of exclusion criteria, and the outcomes of excluded patients are rarely tracked. The frequent use of psychosocial exclusions is especially compromising to generalizability because chronic pain commonly co-occurs with psychiatric comorbidities. Inclusion of more representative patients in research samples can reduce recruitment barriers and broaden the generalizability of findings in patients with chronic pain. We also call for more studies that examine the use of exclusion criteria in chronic pain trials to better understand their implications.</p>","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9663135/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10835323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using evoked compound action potentials to quantify differential neural activation with burst and conventional, 40 Hz spinal cord stimulation in ovines.","authors":"David A Dinsmoor,&nbsp;Joshua O Usoro,&nbsp;Noah D Barka,&nbsp;Tina M Billstrom,&nbsp;Leonid M Litvak,&nbsp;Lawrence R Poree","doi":"10.1097/PR9.0000000000001047","DOIUrl":"https://doi.org/10.1097/PR9.0000000000001047","url":null,"abstract":"<p><p>Unlike conventional dorsal spinal cord stimulation (SCS)-which uses single pulses at a fixed rate-burst SCS uses a fixed-rate, five-pulse stimuli cluster as a treatment for chronic pain; mechanistic explanations suggest burst SCS differentially modulate the medial and lateral pain pathways vs conventional SCS. Neural activation differences between burst and conventional SCS are quantifiable with the spinal-evoked compound action potential (ECAP), an electrical measure of synchronous neural activation.</p><p><strong>Methods: </strong>We implanted 7 sheep with a dorsal stimulation lead at T9/T10, a dorsal ECAP sensing lead at T6/T7, and a lead also at T9/T10 but adjacent to the anterolateral system (ALS). Both burst and conventional SCS with stimulation amplitudes up to the visual motor threshold (vMT) were delivered to 3 different dorsal spinal locations, and ECAP thresholds (ECAPTs) were calculated for all combinations. Then, changes in ALS activation were assessed with both types of SCS.</p><p><strong>Results: </strong>Evoked compound action potential thresholds and vMTs were significantly higher (<i>P</i> < 0.05) with conventional vs burst SCS, with no statistical difference (<i>P</i> > 0.05) among stimulation sites. However, the vMT-ECAPT window (a proxy for the useable therapeutic dosing range) was significantly wider (<i>P</i> < 0.05) with conventional vs burst SCS. No significant difference (<i>P</i> > 0.05) in ALS activation was noted between conventional and burst SCS.</p><p><strong>Conclusion: </strong>When dosed equivalently, no differentially unique change in ALS activation results with burst SCS vs conventional SCS; in addition, sub-ECAPT burst SCS results in no discernable excitability changes in the neural pathways feeding pain relevant supraspinal sites.</p>","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/a9/45/painreports-7-e1047.PMC9663139.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40695670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasma and interstitial levels of endocannabinoids and N-acylethanolamines in patients with chronic widespread pain and fibromyalgia: a systematic review and meta-analysis.","authors":"Inna Kurlyandchik,&nbsp;Romy Lauche,&nbsp;Evelin Tiralongo,&nbsp;Leon N Warne,&nbsp;Janet Schloss","doi":"10.1097/PR9.0000000000001045","DOIUrl":"https://doi.org/10.1097/PR9.0000000000001045","url":null,"abstract":"<p><p>The endocannabinoid system (ECS) is an essential endogenous signaling system that may be involved in the pathophysiology of chronic widespread pain (CWP) and fibromyalgia syndrome (FMS). Further research is required to understand the role of ECS in the development and maintenance of CWP and FMS. We provided the first systematic review and meta-analysis exploring the clinical relevance of ECS alterations in patients with CWP and FMS by comparing plasma and interstitial levels of endocannabinoids and N-acylethanolamines in patients and healthy controls. A systematic search was conducted to identify studies that measured plasma and/or interstitial levels of endocannabinoids and N-acylethanolamines in patients with CWP or FMS and healthy controls. A total of 8 studies were included for qualitative review, and 7 studies were included for meta-analysis. The findings identified increased plasma levels of oleoylethanolamide and stearoylethanolamide in patients with FMS compared with those in controls (<i>P</i> = 0.005 and <i>P</i> < 0.0001, respectively) and increased plasma levels of palmitoylethanolamide and interstitial levels of stearoylethanolamide in patients with CWP compared with those in controls (<i>P</i> = 0.05 and <i>P</i> = 0.001, respectively). There were no significant differences in other ECS parameters. Most studies did not account for variables that may influence ECS function, including cannabis use, concomitant medication, comorbidities, physical activity, stress levels, circadian rhythm, sleep quality, and dietary factors, suggesting that future studies should explore the correlation between these variables and endocannabinoid activity. We highlight the importance of investigating endocannabinoid activity in CWP and FMS because it will underpin future translational research in the area.</p>","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9646668/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40489564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial intelligence and machine learning in pain research: a data scientometric analysis.","authors":"Jörn Lötsch, Alfred Ultsch, Benjamin Mayer, Dario Kringel","doi":"10.1097/PR9.0000000000001044","DOIUrl":"10.1097/PR9.0000000000001044","url":null,"abstract":"<p><p>The collection of increasing amounts of data in health care has become relevant for pain therapy and research. This poses problems for analyses with classical approaches, which is why artificial intelligence (AI) and machine learning (ML) methods are being included into pain research. The current literature on AI and ML in the context of pain research was automatically searched and manually curated. Common machine learning methods and pain settings covered were evaluated. Further focus was on the origin of the publication and technical details, such as the included sample sizes of the studies analyzed with ML. Machine learning was identified in 475 publications from 18 countries, with 79% of the studies published since 2019. Most addressed pain conditions included low back pain, musculoskeletal disorders, osteoarthritis, neuropathic pain, and inflammatory pain. Most used ML algorithms included random forests and support vector machines; however, deep learning was used when medical images were involved in the diagnosis of painful conditions. Cohort sizes ranged from 11 to 2,164,872, with a mode at n = 100; however, deep learning required larger data sets often only available from medical images. Artificial intelligence and ML, in particular, are increasingly being applied to pain-related data. This report presents application examples and highlights advantages and limitations, such as the ability to process complex data, sometimes, but not always, at the cost of big data requirements or black-box decisions.</p>","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9635040/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40454657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterizing <i>OPRM1</i> DNA methylation in prescription opioid users with chronic musculoskeletal pain.","authors":"Sophia Sheikh,&nbsp;Carmen Smotherman,&nbsp;Monika Patel,&nbsp;Taimour Langaee,&nbsp;Danxin Wang,&nbsp;Edward Swaray,&nbsp;Esteban Velasquez,&nbsp;Siegfried O F Schmidt,&nbsp;Phyllis Hendry,&nbsp;Larisa H Cavallari,&nbsp;Roger B Fillingim","doi":"10.1097/PR9.0000000000001046","DOIUrl":"https://doi.org/10.1097/PR9.0000000000001046","url":null,"abstract":"<p><strong>Introduction: </strong>Many patients with chronic pain use prescription opioids. Epigenetic modification of the μ-opioid receptor 1 (<i>OPRM1</i>) gene, which codes for the target protein of opioids, may influence vulnerability to opioid abuse and response to opioid pharmacotherapy, potentially affecting pain outcomes.</p><p><strong>Objective: </strong>Our objective was to investigate associations of clinical and sociodemographic factors with <i>OPRM1</i> DNA methylation in patients with chronic musculoskeletal pain on long-term prescription opioids.</p><p><strong>Methods: </strong>Sociodemographic variables, survey data (Rapid Estimate of Adult Health Literacy in Medicine-Short Form, Functional Comorbidity Index [FCI], PROMIS 43v2.1 Profile, Opioid Risk Tool, and PROMIS Prescription Pain Medication Misuse), and saliva samples were collected. The genomic DNA extracted from saliva samples were bisulfite converted, amplified by polymerase chain reaction, and processed for <i>OPRM1</i>-targeted DNA methylation analysis on a Pyrosequencing instrument (Qiagen Inc, Valencia, CA). General linear models were used to examine the relationships between the predictors and <i>OPRM1</i> DNA methylation.</p><p><strong>Results: </strong>Data from 112 patients were analyzed. The best-fitted multivariable model indicated, compared with their counterparts, patients with > eighth grade reading level, degenerative disk disease, substance abuse comorbidity, and opioid use < 1 year (compared with >5 years), had average methylation levels that were 7.7% (95% confidence interval [CI] 0.95%, 14.4%), 11.7% (95% CI 2.7%, 21.1%), 21.7% (95% CI 10.7%, 32.5%), and 16.1% (95% CI 3.3%, 28.8%) higher than the reference groups, respectively. Methylation levels were 2.2% (95% CI 0.64%, 3.7%) lower for every 1 unit increase in FCI and greater by 0.45% (95% CI 0.08%, 0.82%) for every fatigue T score unit increase.</p><p><strong>Conclusions: </strong><i>OPRM1</i> methylation levels varied by several patient factors. Further studies are warranted to replicate these findings and determine potential clinical utility.</p>","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/bd/99/painreports-7-e1046.PMC9699511.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10634896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electroencephalographic characteristics of children and adolescents with chronic musculoskeletal pain.","authors":"Don Daniel Ocay,&nbsp;Elizabeth F Teel,&nbsp;Owen D Luo,&nbsp;Chloé Savignac,&nbsp;Yacine Mahdid,&nbsp;Stefanie Blain-Moraes,&nbsp;Catherine E Ferland","doi":"10.1097/PR9.0000000000001054","DOIUrl":"https://doi.org/10.1097/PR9.0000000000001054","url":null,"abstract":"<p><strong>Introduction: </strong>The pathophysiology of pediatric musculoskeletal (MSK) pain is unclear, contributing to persistent challenges to its management.</p><p><strong>Objectives: </strong>This study hypothesizes that children and adolescents with chronic MSK pain (CPs) will show differences in electroencephalography (EEG) features at rest and during thermal pain modalities when compared with age-matched controls.</p><p><strong>Methods: </strong>One hundred forty-two CP patients and 45 age-matched healthy controls (HCs) underwent a standardized thermal tonic heat and cold stimulations, while a 21-electrode headset collected EEG data. Cohorts were compared with respect to their EEG features of spectral power, peak frequency, permutation entropy, weight phase-lag index, directed phase-lag index, and node degree at 4 frequency bands, namely, delta (1-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), and beta (13-30 Hz), at rest and during the thermal conditions.</p><p><strong>Results: </strong>At rest, CPs showed increased global delta (<i>P</i> = 0.0493) and beta (<i>P</i> = 0.0002) power in comparison with HCs. These findings provide further impetus for the investigation and prevention of long-lasting developmental sequalae of early life chronic pain processes. Although no cohort differences in pain intensity scores were found during the thermal pain modalities, CPs and HCs showed significant difference in changes in EEG spectral power, peak frequency, permutation entropy, and network functional connectivity at specific frequency bands (<i>P</i> < 0.05) during the tonic heat and cold stimulations.</p><p><strong>Conclusion: </strong>This suggests that EEG can characterize subtle differences in heat and cold pain sensitivity in CPs. The complementation of EEG and evoked pain in the clinical assessment of pediatric chronic MSK pain can better detect underlying pain mechanisms and changes in pain sensitivity.</p>","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9788982/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10489755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distraction from pain depends on task demands and motivation.","authors":"Todd A Vogel,&nbsp;Carl F Falk,&nbsp;A Ross Otto,&nbsp;Mathieu Roy","doi":"10.1097/PR9.0000000000001041","DOIUrl":"https://doi.org/10.1097/PR9.0000000000001041","url":null,"abstract":"<p><strong>Introduction: </strong>Pain captures attention automatically, yet we can inhibit pain when we are motivated to perform other tasks. Previous studies show that engaging in a cognitively demanding task reduces pain compared with a task that is minimally demanding, yet the effects of motivation on this pain-reducing effect remain largely unexplored.</p><p><strong>Objectives: </strong>In this study, we hypothesized that motivating people to engage in a task with high demands would lead to more cognitive resources directed toward the task, thereby amplifying its pain-reducing effects.</p><p><strong>Methods: </strong>On different trials, participants performed an easy (left-right arrow discrimination) or demanding (2-back) cognitive task while receiving nonpainful or painful heat stimuli. In half of the trials, monetary rewards were offered to motivate participants to engage and perform well in the task.</p><p><strong>Results: </strong>Results showed an interaction between task demands and rewards, whereby offering rewards strengthened the pain-reducing effect of a distracting task when demands were high. This effect was reinforced by increased 2-back performance when rewards were offered, indicating that both task demands and motivation are necessary to inhibit pain.</p><p><strong>Conclusions: </strong>When task demands are low, motivation to engage in the task will have little impact on pain because performance cannot further increase. When motivation is low, participants will spend minimal effort to perform well in the task, thus hindering the pain-reducing effects of higher task demands. These findings suggest that the pain-reducing properties of distraction can be optimized by carefully calibrating the demands and motivational value of the task.</p>","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9612955/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40439090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sex-related differences in experimental pain sensitivity in subjects with painful or painless neuropathy after surgical repair of traumatic nerve injuries","authors":"A. Miclescu, Panagiota Gkatziani, Pontus Granlund, Stephen Butler, T. Gordh","doi":"10.1097/PR9.0000000000001033","DOIUrl":"https://doi.org/10.1097/PR9.0000000000001033","url":null,"abstract":"Higher pain intensities at all experimental stimuli but a tendency to faster recovery after cold conditioning stimuli were seen in women with neuropathy in comparison with men. Abstract Introduction: Sex-related influences represent a contributor to greater pain sensitivity and have a higher prevalence of many chronic pain conditions, including neuropathic pain (NP), among women. Objectives: The aim was to analyze how differences in ongoing pain, experimental pain intensity, and conditioned pain modulation (CPM) relate to sex in subjects with neuropathy after traumatic nerve injuries. Methods: Endogenous pain modulation was compared between male (n = 77) and female (n = 55) subjects and between subjects with NP (female = 31, male = 39) and pain-free subjects with posttraumatic neuropathy (female = 24, male = 38). Conditioned pain modulation was assessed by pain ratings to pressure stimuli before and after a noxious conditioning stimulus (CS) conducted with one arm submerged in cold water (4°C) for 1 minute. Time of recovery (Time off) of pain intensity from peak VASmaxc after CS was recorded and compared between male and female patients. Results: Greater ongoing pain intensity was found among female patients compared with male patients and more experimental pain after pressure and cold induced pain. Summing all groups together, women had 0.8 times higher odds (20%) of recovering sooner than men after CS (95% CI = 0.65–2.9). No differences in CPM, time off, and psychosocial variables were seen between female and male patients (P < 0.05). Conclusion: Our hypothesis for sex differences in endogenous pain modulation was only supported by a shorter after-sensation time after cold CS in female patients. No sex differences in the magnitude of CPM effect were identified. Increased pain intensity for experimental pain, in both neuropathic pain and neuropathy without pain, was found in female patients.","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46933484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of stimulation area and temperature rates on offset analgesia","authors":"T. Szikszay, Nina Melz, Barbara von Glasenapp, W. Adamczyk, K. Luedtke","doi":"10.1097/PR9.0000000000001043","DOIUrl":"https://doi.org/10.1097/PR9.0000000000001043","url":null,"abstract":"Supplemental Digital Content is Available in the Text. Two consecutive experiments showed that not the temperature rates but the area of stimulation mediates offset analgesia. Abstract Introduction: Offset analgesia describes the effect of a slightly reduced nociceptive stimulus, resulting in a disproportionate large reduction in the pain perception. This effect may be associated with descending pain inhibition, but parameters influencing this phenomenon are poorly understood. Objectives: In this study, 2 separate experiments were conducted to investigate both, the spatial aspects of offset analgesia and the influence of different rates of temperature rise. Methods: In both experiments, 29 healthy participants received individualized and heat-based offset analgesia paradigms applied to the forearm, with continuous assessment of pain intensity. In experiment 1, offset analgesia paradigms with 3 different rates of temperature rise were applied, whereas in experiment 2, offset analgesia paradigms with 2 different heat application areas were used. Results: The results of experiment 1 showed that different temperature rates had no effect on the offset analgesia response (P > 0.05). Experiment 2, however, showed the influence of the size of a stimulated area on offset analgesia (P = 0.009), which can be explained mainly by the influence of spatial summation of pain and habituation processes. Conclusions: The study showed a lack of influence of different temperature rates on offset analgesia; however, spatial aspects of offset analgesia could be identified. These are most likely based on spatial summation of pain and altered adaptation to pain.","PeriodicalId":52189,"journal":{"name":"Pain Reports","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2022-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45600174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}