Risk Of Chronic Pain Research Articles

The first experience with the Dextile anatomical mesh in laparoscopic inguinal hernia repair.

The Dextile Anatomical mesh (Medtronic) is a polypropylene heavyweight mesh and has a 3D patented anatomical shape which adapts to the contours of the extra-peritoneal inguinal region without the need for fixation, potentially reducing the risk of hernia recurrence and chronic post-operative pain. This retrospective study will be the first study to assess the outcomes of the Dextile Anatomical mesh compared to another three-dimensional mesh, the 3DMax mesh (Bard). Between 2019 and 2022, all patients who underwent an elective unilateral inguinal hernia repair were assessed. 416 patients in the Dextile Anatomical mesh group and 540 patients in the 3DMax mesh group were included. Outcomes were intra- and post-operative complications, inguinal hernia recurrence and chronic post-operative inguinal pain. No significant differences were found between the two groups regarding intra- and post-operative complications including wound infection, antibiotic use, hematoma, seroma, urinary retention and delayed wound healing. 1-year recurrence rate was comparable for the Dextile Anatomical mesh group and the 3DMax mesh group, respectively, 3.8% and 3.0%, P = 0.45. Chronic post-operative inguinal pain was similar for the Dextile Anatomical mesh (3.4%) and the 3DMax mesh (3.0%), P = 0.72. This retrospective study comparing the relatively new Dextile Anatomical mesh (Medtronic) with the 3D Max mesh (Bard) in unilateral inguinal hernia repair showed that both meshes are safe and effective to use. There were no significant differences in intra-operative outcomes, recurrence rates and chronic post-operative inguinal pain.

Effectiveness of pain treatment for patients with mine-blast wounds depending on the number of localizations in military mobile hospitals

Patients with gunshot wounds suffer from chronic pain in 70% of cases, and those with mine-blast wounds – in 83.3% of cases. Civilian patients, after serious injuries, in 11-40% of cases. Unfortunately, there is not enough data to study the causes of such a high frequency of pain chronicity. Therefore, the study of the results of pain treatment at the stage of treatment in military mobile hospitals may be able to reveal the reasons for such a high frequency of chronicity.
 Methods. The treatment of 280 patients with mine-blast wounds was analyzed. The intensity of pain was diagnosed using a visual analog scale. The Shapiro-Wilk test was used to check the distribution of quantitative indicators for normality. The law of distribution differed from the normal one, the median value (Me) and interquartile range (QI-QIII) were given to present quantitative indicators, and the comparison of indicators in the two groups was performed by the Mann-Whitney test. To analyze the dynamics of indicators, the Friedman criterion for linked samples was used, and the posterior comparison was performed using the Bonferroni correction. For qualitative indicators, the absolute frequency of the trait and the relative frequency (%) are presented, and the chi-square test with the correction for continuity was used to compare the two groups. In all cases, the critical level of significance was set at 0.05.
 Results. The analysis of pain intensity according to the VAS, before anesthesia, upon admission to military mobile hospitals, showed that patients experienced high-intensity pain reaching 7 points. This indicates a lack of effective pain control both at the initial stage of treatment and during evacuation. After anesthesia, VAS data indicate the presence of moderate pain – 4 points. The intervals between analgesic treatments averaged 6 hours. Although the effectiveness of analgesia according to VAS was low.
 Conclusions. Patients with mine-blast injuries have a very high risk of chronic pain – 57.5% higher than in injured patients in civilian life. The study results point to ways to improve treatment outcomes for this category of patients. Achieving high-quality pain control at the stage of treatment in military mobile hospitals and maintaining the continuity of treatment during an evacuation can potentially reduce the incidence of pain chronicity.

Trauma in childhood is associated with greater pain catastrophizing but not anxiety sensitivity: a cross-sectional study.

Adverse life experiences have been identified as a possible vulnerability factor for chronic pain. This association could result from the effect of trauma on the psychological state of individuals. Previous studies found childhood trauma to be associated with pain catastrophizing and anxiety sensitivity, both of which have been associated with an increased risk of chronic pain. However, it is unknown whether trauma in adulthood affects these variables and whether the effect on pain catastrophizing is independent of confounds such as depression and anxiety. To test the effect of childhood and adulthood trauma on pain catastrophizing and anxiety sensitivity whilst controlling for depression and anxiety. In the current study, we conducted an online survey in the United Kingdom in a chronic pain sample (N = 138; 123 women; age range 19-78). We analysed whether there is an association between different types of trauma (both in childhood and through the lifespan), pain catastrophizing, and anxiety sensitivity while controlling for anxiety and depression. We found that childhood trauma (particularly emotional abuse) significantly predicts pain catastrophizing, even when controlling for depression and anxiety, whereas it did not have a significant effect on anxiety sensitivity. Trauma through the lifespan (not childhood) did not have a significant effect on anxiety sensitivity nor did it have a significant effect on pain catastrophizing. Our results show that the life stage in which trauma occurs is key in its psychological effects on patients with chronic pain. Furthermore, it shows that trauma affects some psychological variables but not others.

PAIN WITH A NEUROPATHIC COMPONENT IN COMBATANTS AFTER GUNSHOT WOUNDS

Background. In combatants with gunshot wounds, the frequency of pain chronicization is observed in 63.4-78.5% of cases. The reason for this high frequency of chronicization may be a neuropathic component. However, this hypothesis remains unexplored.
 Aim: To study the frequency of neuropathic pain in combatants after gunshot wounds.
 Materials and methods. We analyzed the treatment of 769 combatants after gunshot wounds. The neuropathic component of pain was identified using the Douleur Neuropathique 4 questions. The statistical analysis was performed using the Shapiro-Wilk, Friedman, chi-square, and Bonferroni correction.
 Results. The obtained data indicate that all combatants with chronic pain after gunshot wounds have a neuropathic component of pain (DN4 - from 4 to 5 points). Moreover, the results between the groups did not differ after 1 month - p=0.918, and after 3 months - 0.713, 6 months - p=0.824 and 12 months - p=0.911.
 Conclusion. Combatants who sustained gunshot wounds have a high risk of chronic pain. It was found that the neuropathic component of pain is present in all patients in this category, so it may be one of the key components of such a high frequency of pain chronicity, which requires further research.

Impact of sex on ventral hernia repair outcomes: A systematic review and meta-analysis

BackgroundGiven the variability in abdominal physiology and hernia presentation between sexes, better comprehension of sex-related differences in outcomes would tailor surgical approach and counseling regarding postoperative outcomes. This meta-analysis aims to appraise the effect of sex on the outcomes of ventral hernia repair. MethodsA literature search in PubMed, EMBASE and Cochrane selected studies comparing outcomes of ventral hernia repair between sexes. Postoperative outcomes were assessed by pooled and meta-analysis. Statistical analysis was performed using RevMan 5.4. ResultsWe screened 3128 studies, reviewed 133, and included 18 observational studies, which encompassed 220,799 patients following ventral hernia repair. Postoperative chronic pain was significantly higher in female (OR 1,9; 95% CI 1,64–2,2; p ​< ​0,001). There were no significant differences in complications, readmission, or recurrence rates between females and males. ConclusionFemale sex is associated with a higher risk of postoperative chronic pain following ventral hernia repair.

Factors Contributing to the Link between Physical Well-Being and Chronic Pain in Young People from Galicia, Northwest Spain.

Introduction: The relation between physical well-being and chronic pain is complex and involves several subjective and objective covariates. We aimed to assess the role of mediator, confounder, or interactor played by covariates, including sleep quality, physical activity, perceived stress, smoking, and alcohol drinking in the relation between physical well-being and chronic pain. Method: We used Poisson regression to obtain incidence rate ratios (IRR) of the association between physical well-being and chronic pain in a cohort study carried out among university students. We applied General Structural Equation Modeling (GSEM) to assess mediation and stratum-specific analyses to distinguish confounding from interaction. We computed Relative Excess Risks due to Interaction (RERI), Attributable Proportion (AP), and the Synergy index (S) to measure additive interaction. Results: High physical well-being is related to a large decrease in the risk of chronic pain (IRRTotal Effect = 0.58; 95% CI: 0.50-0.81). Perceived stress mediates 12.5% of the total effect of physical well-being on chronic pain. The stratum-specific IRRs of current smokers and non-current smokers were different from each other and were larger than the crude IRR (IRR = 1.49; 95% CI: 1.24-1.80), which indicates that smoking could be both confounder and interactor. Interaction analyses showed that physical activity could act as a potential interactor (RERI = 0.25; 95% CI: 0.13, 0.60). Conclusions: Perceived stress is an important mediator of the relation between physical well-being and chronic pain, while smoking is both a confounder and an interactor. Our findings may prove useful in distinguishing high-risk groups from low-risk groups, in the interventions aimed at reducing chronic pain.

Impaired Ventrolateral Periaqueductal Gray-Ventral Tegmental area Pathway Contributes to Chronic Pain-Induced Depression-Like Behavior in Mice.

Chronic pain conditions within clinical populations are correlated with a high incidence of depression, and researchers have reported their high rate of comorbidity. Clinically, chronic pain worsens the prevalence of depression, and depression increases the risk of chronic pain. Individuals suffering from chronic pain and depression respond poorly to available medications, and the mechanisms underlying the comorbidity of chronic pain and depression remain unknown. We used spinal nerve ligation (SNL) in a mouse model to induce comorbid pain and depression. We combined behavioral tests, electrophysiological recordings, pharmacological manipulation, and chemogenetic approaches to investigate the neurocircuitry mechanisms of comorbid pain and depression. SNL elicited tactile hypersensitivity and depression-like behavior, accompanied by increased and decreased glutamatergic transmission in dorsal horn neurons and midbrain ventrolateral periaqueductal gray (vlPAG) neurons, respectively. Intrathecal injection of lidocaine, a sodium channel blocker, and gabapentin ameliorated SNL-induced tactile hypersensitivity and neuroplastic changes in the dorsal horn but not depression-like behavior and neuroplastic alterations in the vlPAG. Pharmacological lesion of vlPAG glutamatergic neurons induced tactile hypersensitivity and depression-like behavior. Chemogenetic activation of the vlPAG-rostral ventromedial medulla (RVM) pathway ameliorated SNL-induced tactile hypersensitivity but not SNL-elicited depression-like behavior. However, chemogenetic activation of the vlPAG-ventral tegmental area (VTA) pathway alleviated SNL-produced depression-like behavior but not SNL-induced tactile hypersensitivity. Our study demonstrated that the underlying mechanisms of comorbidity in which the vlPAG acts as a gating hub for transferring pain to depression. Tactile hypersensitivity could be attributed to dysfunction of the vlPAG-RVM pathway, while impairment ofthe vlPAG-VTA pathway contributed to depression-like behavior.

Persistent Pain After Thoracic Surgery-What Works, What Doesn't.

Patients that present for thoracic surgical procedures may already sustain respiratory dysfunction due to their underlying condition. Pulmonary function can often worsen during their recovery phase, often due to surgical pain. Poorly controlled pain is one of m any factors that influence the development of persistent postoperative pain (PPP) after thoracic surgery. Anesthesiologists can impact the quality of recovery in these patients by recognizing the risk of chronic thoracic pain and utilizing techniques that may reduce its occurrence. A systematic review and meta-analysis by Wang and colleagues helps identify the prevalence of PPP after thoracic surgery and its characteristics as seen in this infographic. Makkad and colleagues additionally help us to understand which techniques and interventions appear to be effective in treating pain associated with thoracic surgery based on an analysis of available literature. The reader is strongly encouraged to review the cited articles for an in-depth understanding of the concepts summarized in this infographic.

Candidate gene association study suggests potential role of dopamine beta-hydroxylase in pain heterogeneity in sickle cell disease.

Introduction: Pain is a lifelong companion of individuals with sickle cell disease (SCD) and has a severe impact on their quality of life. Both acute crisis pain and chronic non-crisis pain exhibit high variability between individuals, making it difficult to effectively manage sickle cell-related pain. We investigated the role of dopamine beta-hydroxylase (DBH) gene polymorphisms on pain variability in SCD. DBH is a key enzyme in the catecholamine biosynthesis pathway that catalyzes the conversion of dopamine to norepinephrine, both of which are known mediators of pain and pain-related behaviors. Methods: Acute crisis pain-related utilization and non-crisis chronic pain scores of 131 African Americans with SCD were obtained. Results and discussion: Association analyses revealed that the T allele of upstream variant rs1611115 and downstream variant rs129882 correlated with higher severity of chronic pain in an additive model. On the other hand, the A allele of missense variant rs5324 associated with lower risk of both acute crisis pain and chronic pain. Similarly, the C allele of intronic variant rs2797849 was associated with lower incidence of acute crisis pain in the additive model. In addition, tissue-specific eQTL revealed that the T allele of rs1611115 correlated with decreased expression of DBH in the frontal cortex and anterior cingulate cortex (GTEx), and decreased expression of DBH-AS1 in blood (eQTLGen). Bioinformatic approaches predicted that rs1611115 may be altering a transcription factor binding site, thereby, contributing to its potential effect. Taken together, findings from this study suggest that potential functional polymorphisms of DBH may modulate pain perception in SCD.

An international survey of 1014 hernia surgeons: outcome of GLACIER (global practice of inguinal hernia repair) study.

The practice of inguinal hernia repair varies internationally. The global practice of inguinal hernia repair study (GLACIER) aimed to capture these variations in open, laparoscopic, and robotic inguinal hernia repair. A questionnaire-based survey was created on a web-based platform, and the link was shared on various social media platforms, personal e-mail network of authors, and e-mails to members of the endorsed organisations, which include British Hernia Society (BHS), The Upper Gastrointestinal Surgical Society (TUGSS), and Abdominal Core Health Quality Collaborative (ACHQC). A total of 1014 surgeons from 81 countries completed the survey. Open and laparoscopic approaches were preferred by 43% and 47% of participants, respectively. Transabdominal pre-peritoneal repair (TAPP) was the favoured minimally invasive approach. Bilateral and recurrent hernia following previous open repair were the most common indications for a minimally invasive procedure. Ninety-eight percent of the surgeons preferred repair with a mesh, and synthetic monofilament lightweight mesh with large pores was the most common choice. Lichtenstein repair was the most favoured open mesh repair technique (90%), while Shouldice repair was the favoured non-mesh repair technique. The risk of chronic groin pain was quoted as 5% after open repair and 1% after minimally invasive repair. Only 10% of surgeons preferred to perform an open repair using local anaesthesia. This survey identified similarities and variations in practice internationally and some discrepancies in inguinal hernia repair compared to best practice guidelines, such as low rates of repair using local anaesthesia and the use of lightweight mesh for minimally invasive repair. It also identifies several key areas for future research, such as incidence, risk factors, and management of chronic groin pain after hernia surgery and the clinical and cost-effectiveness of robotic hernia surgery.

Kinins' Contribution to Postoperative Pain in an Experimental Animal Model and Its Implications.

Postoperative pain causes discomfort and disability, besides high medical costs. The search for better treatments for this pain is essential to improve recovery and reduce morbidity and risk of chronic postoperative pain. Kinins and their receptors contribute to different painful conditions and are among the main painful inflammatory mediators. We investigated the kinin's role in a postoperative pain model in mice and reviewed data associating kinins with this painful condition. The postoperative pain model was induced by an incision in the mice's paw's skin and fascia with the underlying muscle's elevation. Kinin levels were evaluated by enzyme immunoassays in sham or operated animals. Kinin's role in surgical procedure-associated mechanical allodynia was investigated using systemic or local administration of antagonists of the kinin B1 receptor (DALBk or SSR240612) or B2 receptor (Icatibant or FR173657) and a kallikrein inhibitor (aprotinin). Kinin levels increased in mice's serum and plantar tissue after the surgical procedure. All kinin B1 or B2 receptor antagonists and aprotinin reduced incision-induced mechanical allodynia. Although controversial, kinins contribute mainly to the initial phase of postoperative pain. The kallikrein-kinin system can be targeted to relieve this pain, but more investigations are necessary, especially associations with other pharmacologic targets.

Socioeconomic Status, Knee Pain, and Epigenetic Aging in Community-Dwelling Middle-to-Older Age Adults

Chronic musculoskeletal pain is often associated with lower socioeconomic status (SES). SES correlates with psychological and environmental conditions that could contribute to the disproportionate burden of chronic stress. Chronic stress can induce changes in global DNA methylation and gene expression, which increases risk of chronic pain. We aimed to explore the association of epigenetic aging and SES in middle-to-older age individuals with varying degrees of knee pain. Participants completed self-reported pain, a blood draw, and answered demographic questions pertaining to SES. We used an epigenetic clock previously associated with knee pain (DNAmGrimAge) and the subsequent difference of predicted epigenetic age (DNAmGrimAge-Diff). Overall, the mean DNAmGrimAge was 60.3 (±7.6), and the average DNAmGrimAge-diff was 2.4 years (±5.6 years). Those experiencing high-impact pain earned less income and had lower education levels compared to both low-impact and no pain groups. Differences in DNAmGrimAge-diff across pain groups were found, whereby individuals with high-impact pain had accelerated epigenetic aging (∼5 years) compared to low-impact pain and no pain control groups (both ∼1 year). Our main finding was that epigenetic aging mediated the associations of income and education with pain impact, as such the relationship between SES and pain outcomes may occur through potential interactions with the epigenome reflective of accelerated cellular aging. PerspectiveSocioeconomic status (SES) has previously been implicated in the pain experience. The present manuscript aims to present a potential social–biological link between SES and pain via accelerated epigenetic aging.

Chronic pain is no more prevalent in people living with HIV than in their uninfected counterparts in South Africa.

There are few studies on chronic pain prevalence in people living with HIV, and there are no studies comparing chronic pain prevalence in an HIV-infected group (HIV+) to that found in an uninfected group (HIV-) in the same population. This study was undertaken to (1) estimate the chronic pain prevalence in HIV+ individuals and (2) compare chronic pain prevalence between HIV+ and HIV- groups in a population. Individuals ≥15 years old were recruited using multi-stage probability sampling in the 2016 South African Demographic and Health Survey. In an interview, participants were asked whether they currently had pain or discomfort, and if so, whether that pain or discomfort had persisted for at least 3 months (operational definition of chronic pain). Blood samples were taken from a volunteering sub-sample for HIV testing. A total of 6584 of 12,717 eligible individuals answered the questionnaire and were tested for HIV. Mean age: 39.1 years (95% confidence interval [CI]: 38.3-39.9), per cent female: 55% (95% CI: 52-56) and tested HIV+: 19% (95% CI: 17-20). The prevalence of chronic pain was 19% (95% CI: 16-23) in the HIV+ group, which was similar to that found in the HIV- group (20% [95% CI: 18-22]; odds ratio [adjusted for age, sex, socio-economic status] = 0.93 [95% CI: 0.74-1.17], p-value = 0.549). The prevalence of chronic pain in South Africans living with HIV was approximately 20%, and having HIV was not associated with an increased risk of chronic pain. Using data from a large, national, population-based study in South Africa, I show for the first time that the prevalence of chronic pain in that population did not differ materially between the part of the population that was living with HIV compared with their uninfected counterparts (both approximately 20%). These findings run counter to the dogma that there is a greater risk of having pain in people living with HIV.

Presence of a neuropathic pain component in patients with chronic pain after gunshot wounds

In patients with gunshot wounds, chronic pain is observed in 70% of cases. One of the factors that influence such a high frequency of pain chronicity is the number of localizations of injured anatomical parts of the body – in patients with injuries in 1 or 2 anatomical parts of the body, the frequency of chronicity is 69.7%, and in patients with injuries in 3 – 71.2% of cases. Also, the presence of a neuropathic component of pain in this category of patients and its possible impact on such a high frequency of chronicity remains unexplored.&#x0D; Materials. The treatment of 769 patients was analyzed. The Douleur Neuropathique 4 questions were used to identify neuropathic pain. The Shapiro-Wilk, Mann-Whitney, Friedman's Bonferroni correction, and chi-square test with a continuity correction were also used. In all cases, the critical level of significance was set at 0.05.&#x0D; Results. Douleur Neuropathique 4 questions data indicate that all patients had a neuropathic pain component (scores range from 4 to 5). At the time of discharge at the stage of treatment in military medical clinical centers, we observed the absence of a neuropathic component of pain in some patients – these were those patients who did not have chronic pain. After 1 month – p=0.918, 3 months – 0.713, 6 months – p=0.824, and 12 months – p=0.911 observation, the data did not differentiate.&#x0D; Conclusions. Patients who received gunshot wounds have a high risk of chronic pain. It was found that the neuropathic component of pain is present in all patients of this category, so it may be one of the key components of such a high frequency of chronicity.

Postoperative Chronic Pain Syndrome and Risk Factors in Patients with Breast Surgery.

To investigate the incidence of chronic postoperative pain after different types of breast surgery, and investigate the risk factors associated with chronic postoperative pain. Descriptive study. Place and Duration of the Study: Ankara University, Faculty of Medicine, Ibnisina Hospital, from January to May 2021. Postoperative chronic pain syndrome and risk factors were investigated in 200 female patients who underwent breast surgery for different reasons. The relationships between preoperative chronic pain, analgesic drug use, number of previous surgeries, anxiety, depression levels, lifestyle, age, height, body mass index, education level, postoperative acute pain, and postoperative sixth-month pain level were statistically analysed. Chronic postoperative pain was observed at a rate of 30%. Postmastectomy syndrome was observed with a rate of 31.6%. A statistically significant relationship was found between preoperative chronic pain, smoking, analgesic use, and postoperative chronic pain (p<0.001). Total mastectomy, mastectomy and simultaneous reconstructive surgery, axillary surgery were associated with chronic pain (p<0.001). A strong correlation was observed between preoperative anxiety (r=0.758, p<0.001), depression (r=0.773, p<0.001), and chronic pain. Chronic postoperative pain and postmastectomy pain syndrome are found in almost one-third of the operated patients mainly related to preoperative smoking, analgesic use, breast cancer, and psychological state. Chronic pain, Breast neoplasms, Mastectomy, Anxiety, Depression.

Postoperative Chronic Pain Syndrome and Risk Factors in Patients with Breast Surgery

Postoperative Chronic Pain Syndrome and Risk Factors in Patients with Breast Surgery

0480 Psychoactive Substance Use and Sleep Characteristics Among Individuals with Untreated Obstructive Sleep Apnea

Abstract Introduction Obstructive sleep apnea (OSA) is characterized by recurrent airway obstruction causing intermittent hypoxia, arousal from sleep, and autonomic instability, and is associated with a variety of long-term health sequala. The fragmented sleep resulting from these respiratory events leads to disruption in normal sleep architecture and progression to deeper stages of sleep, a potential mediator for some of the functional and neurocognitive impairments seen in this population. Similarly, psychoactive substance use (i.e., nicotine, alcohol, and caffeine) impacts sleep architecture in healthy individuals, but their effects in those with OSA have not been well described. We aimed to describe the association between psychoactive substance use and sleep characteristics and daytime symptoms in individuals with untreated OSA. Methods We performed a secondary, cross-sectional analysis of The Apnea Positive Pressure Long-term Efficacy Study (APPLES). Exposures included current smoking, alcohol, and caffeine use in individuals with untreated OSA. Outcome domains included subjective and objective sleep characteristics, daytime symptoms, and co-morbid conditions. Linear or logistic regression assessed the association between substance use and each domain (e.g., self-reported sleep duration, total polysomnographic sleep time, sleepiness, and anxiety). Results Of the 919 individuals with untreated OSA, 116 (12.6%) were current cigarette smokers, 585 (63.7%) were moderate or heavy alcohol users, and 769 (83.7%) were moderate or heavy caffeine users. Current smokers exhibited lower sleep duration (0.3 hours) and longer sleep latency (5 minutes) compared with non-smokers (all p-values&amp;lt; 0.05). REM sleep increased in those with moderate and heavy alcohol use (2.5 and 5% of total sleep time respectively), and moderate caffeine use (2%, all p-values &amp;lt; 0.05)). The combined smoker plus caffeine group exhibited shorter sleep duration (0.4 hours) and higher risk for chronic pain [Odds Ratio (95%CI) = 4.83 (1.57, 14.9). . Conclusion Both psychoactive substances and untreated OSA impact normal sleep architecture, their cumulative effect may have clinical implications in this subgroup. Stimulating or sedating substances may be used in OSA patients to mitigate daytime and nighttime symptoms respectively. Further investigation into the effects substances have on this population may present opportunities to better understand disease mechanisms and increase the effectiveness of treatment in OSA Support (if any)

Risk of osteopaenia, osteoporosis and osteoporotic fractures in patients with chronic pancreatitis: A systematic review and meta-analysis

Chronic pancreatitis results in irreversible pancreatic dysfunction and malnutrition which, alongside excess alcohol intake, can increase the risk of low bone density. Osteoporosis increases the risk of fractures and chronic bone pain, reduces quality of life, and poses considerable costs to healthcare. Despite this, there remains a paucity of literature evaluating bone health in this patient population. This systematic review and meta-analysis evaluated the prevalences of osteopaenia, osteoporosis and fractures in patients with chronic pancreatitis. A comprehensive search of Medline, Embase, ClinicalTrials.gov, and CENTRAL databases was undertaken to identify eligible studies from January 2000 to May 2022. The prevalences of osteopenia, osteoporosis and fragility fractures were extracted from the included studies. Where available, a subgroup analysis was performed to compare the likelihood of developing osteoporosis in patients with chronic pancreatitis compared with control. Nineteen studies reporting on 2,027,764 participants (20,460 with chronic pancreatitis and 2,007,304 controls) were included. The pooled prevalence of osteoporosis was 19% (95% CI 13 to 26%; I2=94%). Patients with chronic pancreatitis were more likely to have osteoporosis when compared with those in the control group (OR 2.80, 95% CI 1.86 to 4.21; I2=21%). The prevalences of osteopaenia and fractures in patients with chronic pancreatitis were 37% (95% CI 31 to 44%; I2=81%) and 14% (95% CI 7 to 22%; I2=99%) respectively. The prevalences of osteopenia and osteoporosis are significant in patients with chronic pancreatitis and can increase the risk of developing fractures. Further population-based studies are required to evaluate the disease burden of osteoporotic fractures and associated morbidity and mortality in chronic pancreatitis.

Longitudinal relationships between habitual physical activity and pain tolerance in the general population.

Physical activity (PA) might influence the risk or progression of chronic pain through pain tolerance. Hence, we aimed to assess whether habitual leisure-time PA level and PA change affects pain tolerance longitudinally in the population. Our sample (n = 10,732; 51% women) was gathered from the sixth (Tromsø6, 2007-08) and seventh (Tromsø7, 2015-16) waves of the prospective population-based Tromsø Study, Norway. Level of leisure-time PA (sedentary, light, moderate, or vigorous) was derived from questionnaires; experimental pain tolerance was measured by the cold-pressor test (CPT). We used ordinary, and multiple-adjusted mixed, Tobit regression to assess 1) the effect of longitudinal PA change on CPT tolerance at follow-up, and 2) whether a change in pain tolerance over time varied with level of LTPA. We found that participants with high consistent PA levels over the two surveys (Tromsø6 and Tromsø7) had significantly higher tolerance than those staying sedentary (20.4 s. (95% CI: 13.7, 27.1)). Repeated measurements show that light (6.7 s. (CI 3.4, 10.0)), moderate (CI 14.1 s. (9.9, 18.3)), and vigorous (16.3 s. (CI 6.0, 26.5)) PA groups had higher pain tolerance than sedentary, with non-significant interaction showed slightly falling effects of PA over time. In conclusion, being physically active at either of two time points measured 7-8 years apart was associated with higher pain tolerance compared to being sedentary at both time-points. Pain tolerance increased with higher total activity levels, and more for those who increased their activity level during follow-up. This indicates that not only total PA amount matters but also the direction of change. PA did not significantly moderate pain tolerance change over time, though estimates suggested a slightly falling effect possibly due to ageing. These results support increased PA levels as a possible non-pharmacological pathway towards reducing or preventing chronic pain.

Levels of preoperative cerebrospinal fluid pro-inflammatory mediators and chronic pain after total knee arthroplasty surgery.

Patients undergoing total knee arthroplasty (TKA) surgery are at high risk of chronic postsurgical pain (CPSP). Accumulating evidence suggests an active role of neuroinflammation in chronic pain. However, its role in the progression to CPSP following TKA surgery remains unanswered. Here, we examined the associations between preoperative neuroinflammatory states and pre- and postsurgical chronic pain in TKA surgery. The data of 42 patients undergoing elective TKA surgery for chronic knee arthralgia at our hospital were analyzed in this prospective study. Patients completed the following questionnaires: brief pain inventory (BPI), hospital anxiety and depression scale, painDETECT, and pain catastrophizing scale (PCS). Cerebrospinal fluid (CSF) samples were collected preoperatively and concentrations of IL-6, IL-8, TNF, fractalkine, and CSF-1 were measured by electrochemiluminescence multiplex immunoassay. CPSP severity was ascertained, using the BPI, 6 months postsurgery. While no significant correlation was observed between the preoperative CSF mediator levels and preoperative pain profiles, the preoperative fractalkine level in the CSF showed a significant correlation with CPSP severity (Spearman's rho = -0.525; p = .002). Furthermore, multivariate linear regression analysis revealed that the preoperative PCS score (standardized β coefficient [β]: .11; 95% confidence interval [CI]: 0.06-0.16; p < .001) and CSF fractalkine level (β: -.62; 95% CI: -1.10 to -0.15; p = .012) were independent predictors of CPSP severity 6 months after TKA surgery. We identified the CSF fractalkine level as a potential predictor for CPSP severity following TKA surgery. In addition, our study provided novel insights into the potential role of neuroinflammatory mediators in the pathogenesis of CPSP.