Is it all about sex? Acupuncture for the treatment of pain from a biological and gender perspective

Gender Differences in Amplitude of Low-Frequency Fluctuation Alterations in Healthy Volunteers by Acupuncture on Left "LI 15": A Resting-State fMRI Study

Objectives: This study is aimed at evaluating gender differences in neural activity change response to the acupuncture on left Jianyu (LI 15) in healthy volunteers. Methods: Forty healthy volunteers (20 males and 20 females) received 20-min acupuncture on left LI 15 and underwent functional magnetic resonance imaging (fMRI) scans before and after acupuncture. Amplitude of low-frequency fluctuations (ALFF) in the 0.01-0.08 Hz range were determined for both scans. Paired t-tests were performed on ALFF between two scans separately for the male and female groups to identify neural changes related to acupuncture. Results: After acupuncture, males showed significantly increased ALFF in the left cerebellum and right angular gyrus but decreased ALFF in the left precentral gyrus, left inferior occipital gyrus, and right fusiform gyrus. However, the ALFF change in females is almost negligible. Conclusions: Brain functional activity in response to acupuncture on left LI 15 is noticeably different between males and females. This is preliminary evidence that gender may be an important factor for optimal clinically personalized acupuncture therapy for poststroke shoulder pain in the future.

A novel acupuncture technique at the Zusanli point based on virtual reality and EEG: a pilot study

Introduction

Acupuncture is a Traditional Chinese Medicine (TCM) method that achieves therapeutic effects through the interaction of neurotransmitters and neural regulation. It is generally carried out manually, making the related process expert-biased. Meanwhile, the neural stimulation effect of acupuncture is difficult to track objectively. In recent years, virtual reality (VR) in medicine has been on the fast lane to widespread use, especially in therapeutic stimulation. However, the use of related technologies in acupuncture has not been reported.

Methods

In this work, a novel acupuncture stimulation technique using VR is proposed. To track the stimulation effect, the electroencephalogram (EEG) is used as the marker to validate brain activities under acupuncture.

Results and discussion

After statistically analyzing the data of 24 subjects during acupuncture at the "Zusanli (ST36)" acupoint, it has been determined that Virtual Acupuncture (VA) has at least a 63.54% probability of inducing similar EEG activities as in Manual Acupuncture (MA). This work may provide a new solution for researchers and clinical practitioners using Brain-Computer Interface (BCI) in acupuncture.

Meridian study on the response current affected by acupuncture needling direction

Acupuncture manipulation with needling direction is important for the therapeutic effect based on traditional Chinese medicine theory. However, there is controversy over directional manipulation and therapeutic effect, despite some research showing that acupuncture manipulations may have something to do with therapeutic effect. Moreover, research usually focuses on the therapeutic effects on the acupoints and acupuncture time rather than exploring the manipulation method. This study applies a semiconductor analyzer to investigate the effects of acupuncture manipulation. 10 healthy participants were recruited for the study. We used a cross-over design to compare the effect of different manipulation on individuals. This study employed an Agilent B1500A semiconductor analyzer to investigate the electric characteristics of meridians under directional supplementation and draining manipulation. We measured the electric current of meridians under different manipulation, and compared the difference between supplementation and draining manipulation in healthy individuals. The electric current was significantly larger in supplementation manipulation compared to draining manipulation in the meridians (P < .001). The measured electric current in the same manipulation methods did not show a statistical difference between meridians (P = .094). The different directional manipulation result in different electric currents in humans. Our finding implies that the supplementation and draining manipulation may result in different therapeutic effects clinically as the description of traditional Chinese medicine theory. Therefore, directional manipulation may need to be taken into consideration in future acupuncture studies and clinical management.

The Impact of Gender on the Effectiveness of an Auricular Acupressure Intervention Administered to Community-Dwelling Poor Sleepers: A Cluster Randomized Controlled Trial

BACKGROUND

Women report a higher incidence of sleep problems than men. Few studies addressing the effect of gender on the efficacy of administering auricular acupressure (AA) at shenmen points (heart meridian 7 [HT7]) on sleep quality have been published.

PURPOSE

The primary aim of this study was to investigate the effects of a 4-week AA intervention applied at the HT7 points on sleep quality, perceived physical health, and perceived mental health in community-dwelling individuals with poor self-reported sleep quality. Additional analyses were used to evaluate the gender-specific effects of this intervention.

METHODS

A cluster randomized controlled trial with repeated-measures design was used. One hundred seventy-nine eligible participants were randomly assigned to either the AA group (n = 88; 47 women, 41 men) or the sleep hygiene instruction (SHI) group (n = 91; 52 women, 39 men). The AA group self-administered acupressure at HT7 on both ears for a 4-week period, whereas the SHI group received an SHI information sheet. Outcome measures included the Pittsburgh Sleep Quality Index (PSQI) and the Short-Form Health Survey-12 Version 2, with data collected at baseline and at 2, 4, and 8 weeks posttest.

RESULTS

Linear mixed-model analysis revealed that the participants in the AA group experienced significantly greater reductions in mean PSQI global score and the three indices of sleep latency, subjective sleep quality, and daytime dysfunction than the SHI group at 2 and 4 weeks posttest. The improvements in subjective sleep quality and daytime dysfunction remained at 4 weeks posttest in the AA group, but not in the SHI group. The PSQI global score decreased significantly more in men than women in the AA group between baseline and 4 weeks posttest.

CONCLUSIONS/IMPLICATIONS FOR PRACTICE

Four weeks of self-administered acupressure at HT7 on both ears is an effective intervention for community-dwelling poor sleepers who are over 45 years old. Moreover, the improvements in subjective sleep quality and daytime dysfunction persist for up to 4 weeks after the end of the intervention. This self-administered acupressure intervention is more effective in men than in women in terms of improving sleep quality. Gender bias is known to influence research results and may lead to inappropriate generalizations. Thus, future studies that are performed to build basic scientific evidence should include considerations of the effects of gender in the study design.

Estradiol and Women's Health: Considering the Role of Estradiol as a Marker in Behavioral Medicine

The sex hormone estradiol, as measured through saliva, represents a non-invasive and cost-effective approach to understanding the influence of hormonal factors on physical and psychological well-being among women. Estradiol levels dramatically change at hormonal transitions, such as puberty, menopause, and postpartum. It is at these transitions where women are at increased risk for psychological and somatic distress. Salivary estradiol also has implications for decision-making and has been broadly associated with engagement in health-compromising behaviors which can influence women's ability to cope with and manage chronic health conditions. This review summarizes the evidence for salivary estradiol as a marker of physical and psychological health, and discusses practical information regarding saliva collection and assay. The overall intent is to expand and clarify knowledge of the relation between changes in salivary estradiol and women's health as well as to provide a means of integrating salivary estradiol into future behavioral medicine research.

The Effectiveness of Acupuncture for Plantar Heel Pain: A Systematic Review

Introduction

Plantar heel pain (PHP) is a common complaint, yet there are no definitive guidelines for its treatment. Acupuncture is increasingly used by podiatrists, and there is a need for evidence to validate this practice. It is acknowledged that PHP and acupuncture are both complex phenomena.

Method

A systematic review (PROSPERO no. CRD42012001881) of the effectiveness of acupuncture for PHP is presented. Quality of the studies was assessed by independent assessors with reference to Quality Index (QI), ‘STandards for Reporting Interventions in Controlled Trials of Acupuncture’ (STRICTA) and ‘CONsolidated Standards Of Reporting Trials’ (CONSORT) criteria. Pooling of data, or even close comparison of studies, was not performed.

Results

Five randomised controlled trials and three non-randomised comparative studies were included. High quality studies report significant benefits. In one, acupuncture was associated with significant improvement in pain and function when combined with standard treatment (including non-steroidal anti-inflammatory drugs). In another, acupuncture point PC7 improved pain and pressure pain threshold significantly more than LI4. Other papers were of lower quality but suggest benefits from other acupuncture approaches.

Conclusions

There is evidence supporting the effectiveness of acupuncture for PHP. This is comparable to the evidence available for conventionally used interventions, such as stretching, night splints or dexamethasone. Therefore acupuncture should be considered in recommendations for the management of patients with PHP. Future research should recognise the complexity of PHP, of acupuncture and of the relationship between them, to explore the optimum use and integration of this approach. There is a need for more uniformity in carrying out and reporting such work and the use of STRICTA is recommended.

Gender differences in the neural response to acupuncture: clinical implications

OBJECTIVE

To examine gender differences and similarities in the psychophysical and brain responses to acupuncture at GB34, a point that is frequently used to treat motor function issues in Traditional Chinese Medicine.

METHODS

Functional MRI (fMRI) was used to measure brain activation in response to acupuncture at GB34 (on the right) in 19 healthy participants (9 male, 10 female). De qi sensations were rated to measure their psychophysical responses.

RESULTS

Overall de qi scores did not differ by gender, although females reported greater intensity of aching (p=0.04). Acupuncture activated the hippocampus, thalamus, globus pallidus, caudate body, claustrum, cingulate gyrus, and culmen in males, and the middle and inferior frontal gyrus, precuneus, postcentral gyrus, inferior parietal lobule, superior temporal gyrus, caudate body, insula, fusiform gyrus, cingulate gyrus, amygdala, and parahippocampal gyrus in females. The middle/medial frontal gyrus, middle temporal gyrus, thalamus, globus pallidus, caudate body, uvula, and cerebellar tonsil were activated when data from all subjects were combined. Relative to males, females exhibited greater brain activation in the right-sided postcentral gyrus, precentral gyrus, precuneus, postcentral gyrus, inferior parietal lobule, declive, middle occipital gyrus and parahippocampal gyrus.

CONCLUSIONS

The neural effects of GB34 acupuncture might differ between males and females because different brain structures were modulated in response to acupuncture. This potential gender effect should be taken into account in future clinical research. We also revealed that the caudate body was activated by GB34 acupuncture in both males and females and may represent a major target of GB34 acupuncture.

TRIAL REGISTRATION NUMBER

KMC IRB 0861-06.

Intraoperative Low-frequency Electroacupuncture under General Anesthesia Improves Postoperative Recovery in a Randomized Trial

Neuronal stimulation improves physiological responses to infection and trauma, but the clinical potential of this strategy is unknown. We hypothesized that transdermal neural stimulation through low-frequency electroacupuncture might control the immune responses to surgical trauma and expedite the postoperative recovery. However, the efficiency of electroacupuncture is questioned due to the placebo effect. Here, electroacupuncture was performed on anesthetized patients to avoid any placebo. This is a prospective double-blinded pilot trial to determine whether intraoperative electroacupuncture on anesthetized patients improves postoperative recovery. Patients with electroacupuncture required 60% less postoperative analgesic, even they had pain scores similar to those in the control patients. Electroacupuncture prevented postoperative hyperglycemia and attenuated serum adrenocorticotropic hormone in the older and heavier group of patients. From an immunological perspective, electroacupuncture did not affect the protective immune responses to surgical trauma, including the induction of interleukin-6 and interleukin-10. The most significant immunological effect of electroacupuncture was enhancing transforming growth factor-β1 production during surgery in the older and lighter group of patients. These results suggest that intraoperative electroacupuncture on anesthetized patients can reduce postoperative use of analgesics and improve immune and stress responses to surgery.

A Comparison of the Characteristics of Acupuncture- and Non-Acupuncture-Preferred Consumers: A Secondary Analysis of NHIS 2012 Data

OBJECTIVES

To determine whether acupuncture use, sociodemographic characteristics, and existing health conditions differ between acupuncture-preferred consumers (i.e., those who deem acupuncture to be one of the three most important complementary and alternative medicine [CAM] modalities used) and non-acupuncture-preferred consumers who used acupuncture in the past 12 months

METHODS

This is a secondary analysis of the National Health Interview Survey Sample Adult File and Adult Alternative Medicine datasets collected by the Centers for Disease Control and Prevention during 2012. The sample was drawn from the noninstitutionalized civilian population of the United States. The datasets yielded 34,525 respondents aged 18 years and older. Measures included in the analysis were acupuncture use in the past 12 months, sociodemographic characteristics, and existing health conditions. Analyses were performed by using Stata software, version 9.0 (Stata Corp., College Station, TX).

RESULTS

Of the 10,158 adults who responded to the question regarding the "three most important" CAM modalities used, 572 (5.6%) had used acupuncture in the past 12 months. Of these, 456 (79.7%) chose acupuncture as one of the top three CAM modalities most important to their health. Acupuncture-preferred consumers reported significantly more visits to acupuncturists (7.46 versus 3.99 visits; p < 0.001), as well as higher out-of-pocket costs ($342.8 versus $246.4; p < 0.001), compared with non-acupuncture-preferred consumers. The logistic regression model revealed that with every additional CAM modality used, the likelihood of deeming acupuncture as one of the three CAM modalities most important to one's health decreased by 39% (odds ratio, 0.61; 95% confidence interval, 0.52-0.71; p < 0.001). Health conditions were not statistically significant predictors.

CONCLUSIONS

A consumer's preference for acupuncture appeared not to be driven by health conditions but rather was related to sociodemographic factors. This suggests that health education regarding acupuncture may need to be tailored to certain consumer groups, such as those residing in the South, and could provide more information on the comparative effectiveness of acupuncture for various health conditions.

Women demonstrate more pain and worse function before THA but comparable results 12 months after surgery

BACKGROUND

Many studies report differences in patient-reported outcome measures (PROMs) for men and women undergoing total hip arthroplasty (THA). Few studies have evaluated whether these are explained by corresponding differences in important preoperative factors.

QUESTIONS/PURPOSES

(1) Are there differences between men and women in PROM scores preoperatively and 12 months after THA? (2) Do baseline differences in comorbidity, age, body mass index (BMI), and mental health status explain these differences in PROM scores?

METHODS

Preoperatively, 300 patients completed the Oxford Hip Score (OHS), WOMAC, and SF-12; 261 (86%) of them (129 women, 64 ± 11 years; 132 men, 66 ± 10 years) completed the same questionnaires 12 months postoperatively and also rated the acceptability of their current symptoms and change in general health.

RESULTS

Preoperatively, women showed worse scores than men in the OHS (-1.9; 95% confidence interval, -3.6 to -0.3) and WOMAC (-6.3; -10.9 to -1.7). At 12 months postoperatively, the absolute scores for all PROMs were not significantly different. After controlling for BMI, age, comorbidity, SF-12 mental health scores, and sociodemographic characteristics, the baseline differences remained.

CONCLUSIONS

Surgeons may be more reluctant to operate on women than men because they perceive that, because of their worse baseline status, women are likely to have worse outcomes; however, given that we found no evidence for differences in patient-reported outcomes at 12 months, these suspicions would appear to be unfounded. Women and men can be expected to benefit to a similar extent from THA.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Acupuncture and moxibustion for stress-related disorders

Acupuncture and moxibustion, which medical doctors are licensed by the government of Japan to perform, can improve the psychological relationship between doctors and patients, especially when it is disturbed by a “game”, a dysfunctional interpersonal interaction that is repeated unintentionally. This advantage is due to the essential properties of acupuncture and moxibustion. Acupuncture and moxibustion are helpful in treating somatoform disorders, especially musculoskeletal symptoms. In Japan, a holistic acupuncture and moxibustion therapy called Sawada-style has been developed. This is based on fundamental meridian points that are considered to have effects on central, autonomic nervous, immune, metabolic, and endocrine systems to regulate the whole body balance. In addition, some of the fundamental points have effects on Qi, blood, and water patterns associated with major depression, generalized anxiety disorder, eating disorders, and somatoform disorders. The fixed protocol of Sawada-style would be suitable for large-scale, randomized, controlled studies in the future. Recent systematic reviews indicate that electroacupuncture would be a useful addition to antidepressant therapy for some symptoms accompanying fibromyalgia. Acupuncture and moxibustion are also recommended for irritable bowel syndrome, instead of Western drug therapy. Surprisingly, the dorsal prefrontal cerebral cortex, which is associated with a method of scalp acupuncture applied for gastrointestinal disorders, has been found to be activated in patients with irritable bowel syndrome. It is quite possible that regulation of this cortical area is related to the effect of scalp acupuncture. This acupuncture method can be effective not only for irritable bowel syndrome but also for other stress-related gastrointestinal disorders.

The effect of electroacupuncture on osteosarcoma tumor growth and metastasis: analysis of different treatment regimens

Osteosarcoma is the most common malignant bone tumor found in children and adolescents and is associated with many complications including cancer pain and metastasis. While cancer patients often seek complementary and alternative medicine (CAM) approaches to treat cancer pain and fatigue or the side effects of chemotherapy and treatment, there is little known about the effect of acupuncture treatment on tumor growth and metastasis. Here we evaluate the effects of six different electroacupuncture (EA) regimens on osteosarcoma tumor growth and metastasis in both male and female mice. The most significant positive effects were observed when EA was applied to the ST-36 acupoint twice weekly (EA-2X/3) beginning at postimplantation day 3 (PID 3). Twice weekly treatment produced robust reductions in tumor growth. Conversely, when EA was applied twice weekly (EA-2X/7), starting at PID 7, there was a significant increase in tumor growth. We further demonstrate that EA-2X/3 treatment elicits significant reductions in tumor lymphatics, vasculature, and innervation. Lastly, EA-2X/3 treatment produced a marked reduction in pulmonary metastasis, thus providing evidence for EA's potential antimetastatic capabilities. Collectively, EA-2X/3 treatment was found to reduce both bone tumor growth and lung metastasis, which may be mediated in part through reductions in tumor-associated vasculature, lymphatics, and innervation.

Quality of life in dialysis patients from the United Arab Emirates

BACKGROUND

The quality of life (QOL) has emerged as an important parameter for evaluating the quality of health-care for patients with renal failure. The literature suggests that many factors impact QOL. The QOL of dialysis patients in the United Arab Emirates (UAE) has not been studied before. This research examined the QOL of patients in the UAE on dialysis using two QOL tools.

MATERIALS AND METHODS

A descriptive comparative survey design was used to study 161 dialysis patients. The participants completed the 36-Item Short Form Health Survey (SF-36) and the QOL index dialysis version tool. Comparative analyses of the results for both tools were done using descriptive statistics. Multiple linear regression analysis determines the effect of the variables on the QOL scores.

RESULTS

The questionnaires return rate was 93%. The overall QOL for dialysis patients was rated low when self-assessed using the SF-36 (58.9) compared to QOL index (77.2). The multiple regression analysis revealed that having a chronic illness had the strongest impact on the total scores of both tools. The comparison between the statistically significant variables for both samples revealed contradictory results from the two tools used. This meant that the two tools measured QOL differently.

CONCLUSION

The two QOL tools scores impacted very differently on most socio-demographic variables on the two samples. More studies are required to explore the concept of QOL in the Arab dialysis population.

Irritable bowel syndrome and migraine: bystanders or partners?

Irritable bowel syndrome (IBS) and migraine are distinct clinical disorders. Apart from the characteristics of chronic and recurrent pain in nature, these pain-related disorders apparently share many similarities. For example, IBS is female predominant with community prevalence about 5-10%, whereas that of migraine is 1-3% also showing female predominance. They are often associated with many somatic and psychiatric comorbidities in terms of fibromyaglia, chronic fatigue syndrome, interstitial cystitis, insomnia and depression etc., even the IBS subjects may have coexisted migraine with an estimated odds ratio of 2.66. They similarly reduce the quality of life of victims leading to the social, medical and economic burdens. Their pathogeneses have been somewhat addressed in relation to biopsychosocial dysfunction, heredity, genetic polymorphism, central/visceral hypersensitivity, somatic/cutaneous allodynia, neurolimbic pain network, gonadal hormones and abuses etc. Both disorders are diagnosed according to the symptomatically based criteria. Multidisciplinary managements such as receptor target new drugs, melantonin, antispasmodics, and psychological drugs and measures, complementary and alternatives etc. are recommended to treat them although the used agents may not be necessarily the same. Finally, the prognosis of IBS is pretty good, whereas that of migraine is less fair since suicide attempt and stroke are at risk. In conclusion, both distinct chronic pain disorders to share many similarities among various aspects probably suggest that they may locate within the same spectrum of a pain-centered disorder such as central sensitization syndromes. The true pathogenesis to involve these disorders remains to be clarified in the future.

Nature and nurture of human pain

Humans are very different when it comes to pain. Some get painful piercings and tattoos; others can not stand even a flu shot. Interindividual variability is one of the main characteristics of human pain on every level including the processing of nociceptive impulses at the periphery, modification of pain signal in the central nervous system, perception of pain, and response to analgesic strategies. As for many other complex behaviors, the sources of this variability come from both nurture (environment) and nature (genes). Here, I will discuss how these factors contribute to human pain separately and via interplay and how epigenetic mechanisms add to the complexity of their effects.

Effect of self-management intervention on cortisol and daily stress levels in irritable bowel syndrome

Self-management programs that include cognitive behavioral strategies have been shown to improve gastrointestinal (GI) symptoms, psychological distress, and quality of life (QoL) in persons with irritable bowel syndrome (IBS). However, less is known about the physiological impact of such a change. As part of a randomized controlled trial using a comprehensive self-management (CSM) intervention (n = 126) compared to usual care (UC; n = 62), cortisol levels were measured in 4 weekly first morning urine samples at baseline and at 3-, 6-, and 12-month follow-up. In addition, diary (28 days) ratings of stress were recorded at baseline, 3, 6, and 12 months. The omnibus test of all three outcome times showed no differences in urine cortisol levels between the CSM and UC groups (p = .400); however, at 3 months the CSM group had significantly higher cortisol levels than the UC group (p = .012). The CSM group reported lower daily stress levels (p = .046 from the omnibus test of all 3 time points) than the UC group, with the effect getting stronger over time. Despite marked improvements in reported stress and previously reported GI and psychological distress symptoms at later follow-ups, the CSM program did not reduce urine cortisol levels in adults with IBS. These results suggest that the first-void urine cortisol levels are not reflective of self-reported daily stress in this patient population.

The effects of acupuncture on the brain networks for emotion and cognition: an observation of gender differences

Acupuncture modulates brain activity at the limbic-paralimbic-neocortical network (LPNN) and the default mode network (DMN). Since these brain networks show gender differences when mediating emotional and cognitive tasks, we thus hypothesize that women and men may also respond differently to acupuncture procedure at these brain regions. In order to test this hypothesis, we retrieved the data of 38 subjects, 19 females and 19 males, who had brain fMRI during acupuncture from previous studies and reanalyzed them based on sex status. Deactivation at the LPNN/DMN during needle manipulation of acupuncture was more extensive in females than in males, particularly in the posterior cingulate (BA31), precuneus (BA7m) and angular gyrus (BA39). The functional correlations between the right BA31 and pregenual cingulate (BA32), hippocampus or contralateral BA31 were significantly stronger in females than in males. The angular gyrus (BA39) was functionally correlated with BA31 in females; in contrast, it was anticorrelated with BA31 in males. Soreness, a major component of the psychophysical responses to needle manipulation, deqi, was correlated in intensity with deactivation of the angular gyrus in females; no such relationships were observed in males. In contrast to lesser deactivation at the LPNN/DMN networks, needle manipulation during acupuncture induced greater activation at the secondary somatosensory cortex and stronger functional connectivity with the anterior-middle cingulate (BA32/24) in males than in females. Our study suggests that brains with sex dimorphism may process the acupuncture stimulation differently between women and men.

On the threshold - evaluation of variability in effects of acupuncture in a gender perspective

Variable results of pain alleviation in response to acupuncture have been reported, complicating its interpretation. Sources of variability are probably multi-factorial, including the contribution of gender related effects. Gender related variation in perceived pain has been discussed frequently, but documented effects of acupuncture referring to gender are sparse. Furthermore, factors such as operationalisation of the outcome variable and the statistical method for evaluation could also be sources of variability. When pain is regarded as subjective, the produced data should be treated as ordinal. The rank-based method by Svensson, taking the non-metric qualities of the ordinal data into account as well as the variability at the group and the individual level, is therefore an alternative. The present commentary aims to (1) evaluate changes in electrical sensory thresholds and electrical pain thresholds after low frequency electro-acupuncture separately in healthy women and men; (2) introduce and exemplify the method by Svensson in a user-friendly approach. To analyze the systematic patterns of change in thresholds, indicating evidence of treatment on a group level, the relative position (RP) and relative concentration (RC), were measured. The variation related to the individual, the relative rank variation (RV) was also measured. The results were divergent between women (n = 23) and men (n = 22), i.e. unchanged sensory threshold after acupuncture at the group level in women while changed in men. The assessed pain threshold after acupuncture on the other hand was changed towards higher levels in women and unchanged in men. The individual variation was apparent in both women and men but larger in women. For statistical analysis of the variability for both group and individual related effects, the rank-based method by Svensson could be used. The present study indicates that evaluation of sensory and pain threshold response should be analysed separately in women and men.

Is There a Role for Acupuncture in Endometriosis Pain, Or ‘endometrialgia’?

Endometriosis is a common cause of pelvic pain in women, many of whom suffer a progression of symptoms over their menstrual life. Symptoms may include combinations of abnormal visceral sensations and emotional distress. Endometriosis pain, or ‘endometrialgia’ often has a negative influence on the ability to work, on family relationships and sense of worth.

Endometrialgia is often considered to be a homogeneous sensory entity, mediated by a specialised high threshold sensory system, which extends from the periphery through the spinal cord, brain stem and thalamus to the cerebral cortex. However, multiple mechanisms have been detected in the nervous system responsible for the pain including peripheral sensitisation, phenotypic switches, central sensitisation, ectopic excitability, structural reorganisation, decreased inhibition and increased facilitation, all of which may contribute to the pain.

Although the causes of endometrialgia can differ (eg inflammatory, neuropathic and functional), they share some characteristics. Endometrialgia may be evoked by a low intensity, normally innocuous stimulus (allodynia), or it may be an exaggerated and prolonged response to a noxious stimulus (hyperalgesia). The pain may also be spontaneous in the absence of any apparent peripheral stimulus.

Oestrogens and prostaglandins probably play key modulatory roles in endometriosis and endometrialgia. Consequently many of the current medical treatments for the condition include oral drugs, like non-steroid anti-inflammatory drugs, contraceptives, progestogens, androgenic agents, gonadotrophin releasing hormone analogues, as well as laparoscopic surgical excision of the endometriosis lesions. However, management of pain in women with endometriosis is currently inadequate for many. Possibly acupuncture and cognitive therapy may be used as an adjunct.