Pain Sensitivity In Women Research Articles

Efficacy of manual therapy and pelvic floor exercises for pain reduction in primary dysmenorrhea: A prospective observational study

BackgroundPrimary dysmenorrhea represents one of the most common causes of pelvic and low back pain. Pharmacological treatment can present some side effects, and non-pharmacological treatments should be considered to improve the symptoms of primary dysmenorrhea. The aim of this study was to evaluate the efficacy of manual therapy (MT), pelvic floor exercises (PFE), and their combination (MT + PFE) to improve clinical outcomes and pain sensitivity in women with primary dysmenorrhea. MethodsA prospective observational study was conducted. Thirty females (age 25.0 ± 6.1 y) with history of primary dysmenorrhea participated to 8 sessions of 60 min of either MT, PFE or MT + PFE, twice per week. They participated to the different treatments according to the different services offered by the school of physiotherapy. A 0–10 numeric rating scale (NRS) was administered to assess subjective pain, while short-form 36 (SF-36) was used to evaluate quality of life. The pressure pain threshold (PPT) was assessed with a portable algometer on different pelvic and lumbar areas. ResultsIndependently from the treatment, significant improvements were reported for general pain NRS (p < 0.001; pη2 = 0.511), as well as most the domains of the SF-36, although the general health domain did not reach statistical significance (p = 0.613; pη2 = 0.010). PPT revealed a general improvement in all tested body areas, although on the quadratus lumborum, the PFE treatment did not induce a significant improvement compared to the MT and MT + PFE protocols (p = 0.039). ConclusionsThese findings highlight the importance of proposing physiotherapy treatments to females with primary dysmenorrhea to improve symptoms, with manual therapy combined with active pelvic floor exercise providing the best outcomes including an improvement of lumbar pain thresholds.

Increased Clinical Pain Locations and Pain Sensitivity in Women After Breast Cancer Surgery: Influence of Aromatase Inhibitor Therapy.

Aromatase inhibitors (AIs), which potently inhibit estrogen biosynthesis, are a standard treatment for hormone sensitive early-stage breast cancer. AIs have been associated with substantial joint pain and muscle stiffness (aromatase inhibitor-associated musculoskeletal syndrome). However, the link between AIs and number of clinical pain locations and pain sensitivity are less well understood. The aim of this study was to compare longitudinal changes in clinical pain and quantitative pain sensitivity between women who did or did not receive AI therapy. Women with early-stage breast cancer were prospectively enrolled and assessed for clinical pain in surgical and nonsurgical body areas using the Brief Pain Inventory and Breast Cancer Pain Questionnaire, and for pain sensitivity using quantitative sensory testing preoperatively and at 1 year postoperatively. Pain outcomes between participants who did and did not begin adjuvant AI therapy were compared using Wilcoxon Signed-Ranks and generalized estimating equation linear regression analyses. Clinical pain and pain sensitivity were comparable between AI (n=49) and no-AI (n=106) groups preoperatively. After adjusting for body mass index, AI therapy was associated with a greater increase in the number of painful nonsurgical body sites (significant time by treatment interaction, P =0.024). Pain location was most frequent in knees (28%), lower back (26%), and ankles/feet (17%). Quantitative sensory testing revealed a significant decrease in pain sensitivity (increased pressure pain threshold) in the no-AI group over time, but not in the AI group. AI therapy was associated with increased diffuse joint-related pain and greater post-treatment pain sensitivity, potentially implicating central sensitization as a contributing pain mechanism of aromatase inhibitor-associated musculoskeletal syndrome worthy of future investigation.

Effect of Hormonal Supplementation on Pain Tolerance in Women, A Cross Sectional Study

Background and Aim: Hormonal supplementation (Oestrogen and progesterone) significantly influence pain sensitivity in women. Neuropathic pain prevention and nociceptive actions are strongly affected by progesterone and oestrogen. The present study aimed to investigate the gonadal hormones on women's pain sensation. Materials and Method: this case-control study was conducted on 46 females (study group) on the combined oral contraceptive pill (COCP) and 46 healthy males (control group) at the Department of Physiology, Lahore General Hospital, Lahore from November 2020 to July 2021. As a stimulus source, a cold pressor test was used. The participant’s least dominant hands were placed in a water bath with a temperature between 0◦C and 2◦C and were instructed to notify when the pain was first sensation feel which represents the pain threshold of participants. Pain tolerance was referred to the duration from the initial threshold to a stage where pain severity increased beyond the participant’s coping with pain. A visual analog scale was set to measure the unpleasantness and pain intensity. SPSS version 23 was used for data analysis. The Chi-square test was used, and p values less than 0.05 were considered significant. Results: Pain tolerance and unpleasantness was not significantly differ in men and women taking combined oral contraceptive pill. However, women on combined oral contraceptive pill had significantly higher (p&lt;0.001) pain tolerance on average scale. Average pain threshold had insignificant association with age. Comparing to naturally menstruating women the unpleasantness pain on average scale was less severe in women taking hormonal pills. The average pain intensity was considerably differ between women on COCP pills and normal women. Conclusion: Our study suggests that gonadal hormone levels changes had a lower effect on experimental pain and unpleasantness in women. COCP influence the average pain reported by participants. Upon comparing normal and women on COCP pills, a significant increase in pain tolerance was observed in females on pill therapy. Women utilizing hormonal contraceptives should be kept under supervision for unpleasant and severe pain. Keywords: Hormonal supplementation, Pain tolerance, Combined oral contraceptive pill

Effect of Neuromuscular Electrical Stimulation During Walking on Pain Sensitivity in Women With Obesity With Knee Pain: A Randomized Controlled Trial

ObjectiveTo assess the extent to which pain sensitivity is altered in women with obesity with frequent knee symptoms who walk with either a hybrid training system (HTS) that provides antagonist muscle electrical stimulation vs sensory transcutaneous electrical nerve stimulation (TENS). DesignRandomized, double-blinded, controlled trial. SettingUniversity-based fitness center. ParticipantsTwenty-eight women (N=28) with obesity, aged 40-70 years, with daily knee symptoms. InterventionsParticipants were randomized to 12 weeks of biweekly 30-minute walking exercise with either HTS (HTSW group) or sensory TENS (control group). Main Outcome MeasuresPressure pain thresholds (PPTs) at the more symptomatic knee (local PPT) and PPT at the ipsilateral pain-free wrist (remote PPT). ResultsAfter adjustment for preintervention values and body mass index (BMI), there was a statistically significant improvement in local PPT in the HTSW group compared with the control group (P=.039). After adjustment for pretraining value, age, and BMI, changes in remote PPT when comparing groups did not reach statistical significance, although the HTS group tended to demonstrate increased remote PPT (P=.052) compared with the control group. Moreover, after adjustment for pretraining value, knee pain, and quality of life, comparing groups did not reach statistical significance, although the HTS group tended to demonstrate decreased knee pain (P=.069) compared with the control group. ConclusionsAugmentation of walking exercise with HTS was more effective than application of sensory TENS in improving local pain sensitivity at the knee but not at the wrist in women with obesity with frequent knee symptoms.

Hypohydration but not menstrual phase influences pain perception in healthy women.

Chronic pain is a pervasive health problem and is associated with tremendous socioeconomic costs. However, current pain treatments are often ineffective due, in part, to the multifactorial nature of pain. Mild hypohydration was shown to increase experimental pain sensitivity in men, but whether this also occurs in women has not been examined. Fluctuations in ovarian hormones (i.e., 17β-estradiol and progesterone) throughout the menstrual cycle may influence a woman's pain sensitivity, as well as hydration levels, suggesting possible interactions between hypohydration and menstrual phase on pain. We investigated the effects of mild hypohydration (HYPO, 24 h of fluid restriction) on ischemic pain sensitivity in 14 eumenorrheic women during the early follicular (EF) and mid-luteal (ML) phases of their menstrual cycle. We also examined whether acute water ingestion could reverse the negative effects of hypohydration. Elevated serum osmolality, plasma copeptin, and urine specific gravity indicated mild hypohydration. Compared with euhydration, HYPO reduced pain tolerance (by 34 ± 46 s; P = 0.02, [Formula: see text] = 0.37) and increased ratings of pain intensity (by 0.7 ± 0.7 cm; P = 0.004; [Formula: see text] = 0.55) and unpleasantness (by 0.7 ± 0.9 cm; P = 0.02; [Formula: see text] = 0.40); these results were not influenced by menstrual phase. Water ingestion reduced thirst perception (visual analog scale, by 2.3 ± 0.9 cm; P < 0.001, [Formula: see text] = 0.88) but did not reduce pain sensitivity. Therefore, hypohydration increases pain sensitivity in women with no influence of menstrual phase.NEW & NOTEWORTHY Whether hypohydration can increase pain in women remains untested. Menstrual phase may influence pain, but findings are equivocal and may be confounded by the lack of hydration measures. We found that pain sensitivity in women increased after 24 h of fluid restriction versus ad libitum fluid intake, but did not differ between menstrual phases. Water ingestion did not acutely attenuate the negative effects of hypohydration on pain, highlighting the importance of staying well-hydrated throughout the day.

Gluten-Free Diet Reduces Pain in Women with Myofascial Pain in Masticatory Muscles: A Preliminary Randomized Controlled Trial.

To evaluate the efficacy of a gluten-free diet (GFD) as a treatment modality for pain management in women with chronic myofascial pain in masticatory muscles. In this randomized controlled trial, 39 female subjects were evaluated according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and divided into three groups: a healthy group (n = 14; mean ± SD age = 34.57 ± 9.14 years); a control group (n = 12; age = 31.50 ± 7.38 years); and an experimental group (n = 13; age 30.00 ± 7.64 years). The outcome variables were: pain intensity, mechanical pain threshold (MPT), and pressure pain threshold (PPT). MPT was performed on the masseter muscle, and PPT was performed on both the masseter and anterior temporalis muscles. A nutritionist prescribed a 4-week individualized GFD for the experimental group. The healthy group was analyzed only initially, whereas the control and experimental groups were analyzed again after 4 weeks. Data were subjected to statistical analysis with a significance level of 5% (one-way analysis of variance followed by Bonferroni post hoc, paired t, Wilcoxon signed rank, Kruskal-Wallis/Dunn, and Pearson chi-square tests). Participants who underwent a GFD showed reduction in pain intensity (P = .006) and an increase in PPT of the masseter (P = .017) and anterior temporalis (P = .033) muscles. The intervention did not influence the MPT of the masseter muscle (P = .26). In contrast, the control group showed no improvement in any parameter evaluated. GFD seemed to reduce pain sensitivity in women with TMD and may be beneficial as an adjunctive therapy for chronic myofascial pain in masticatory muscles; however, further studies in the fields of orofacial pain and nutrition are required.

Influence of Aromatase Inhibitors on Pain and Pain Sensitivity in Women with Breast Cancer

Influence of Aromatase Inhibitors on Pain and Pain Sensitivity in Women with Breast Cancer

Do women with vaginismus have a lower threshold of pain?

ObjectiveVaginismus and dyspareunia are together categorized as a genito-pelvic pain and penetration disorder. We aimed to evaluate the threshold of pain and the pain sensitivity in women with vaginismus. Study designIn this prospective case-control study; 32 women with vaginismus and 29 healthy women were enrolled. Sociodemographic Information Form, Female Sexual Function Index (FSFI), Pain Beliefs Questionnaire (PBQ), Revised Fibromyalgia Impact Questionnaire (FIQR), The Lamont Scale of Vaginismus were applied. Threshold of pain was measured with algometer in terms of Newton (N). ResultsThe pain thresholds vaginismus and control group were as follows; left posterior superior iliac crest (40.3 N, 84.9 N respectively;p < 0.001), right posterior superior iliac crest (42.9 N, 76.1 N respectively;p = 0.007), left lateral trochanter (42.0 N, 69.8 N respectively; p = 0.015), right lateral trochanter (43.8 N, 75.3 N respectively; p = 0.003), left anterior superior iliac spine (29.2 N, 51.2 N respectively; p = 0.003), left insertion of gracilis muscle (27.3 N, 45.2 N respectively; p = 0.038), left medial vastus muscle (37.0 N, 52.4 N respectively; p = 0.025) and the pain thresholds were significantly lower in the vaginismus patients. ConclusionWomen with vaginismus have a lower threshold of pain, and the pain threshold decreases in higher grades of vaginismus. The pain may aggravate the avoiding behavior of women from sexual intercourse

Vestibular Anatomic Localization of Pain Sensitivity in Women with Insertional Dyspareunia: A Different Approach to Address the Variability of Painful Intercourse.

The pathophysiology underlying painful intercourse is challenging due to variability in manifestations of vulvar pain hypersensitivity. This study aimed to address whether the anatomic location of vestibular-provoked pain is associated with specific, possible causes for insertional dyspareunia. Women (n = 113) were assessed for “anterior” and “posterior” provoked vestibular pain based on vestibular tenderness location evoked by a Q-tip test. Pain evoked during vaginal intercourse, pain evoked by deep muscle palpation, and the severity of pelvic floor muscles hypertonicity were assessed. The role of potential confounders (vestibular atrophy, umbilical pain hypersensitivity, hyper-tonus of pelvic floor muscles and presence of a constricting hymenal-ring) was analyzed to define whether distinctive subgroups exist. Q-tip stimulation provoked posterior vestibular tenderness in all participants (6.20 ± 1.9). However, 41 patients also demonstrated anterior vestibular pain hypersensitivity (5.24 ± 1.5). This group (circumferential vestibular tenderness), presented with either vestibular atrophy associated with hormonal contraception use (n = 21), or augmented tactile umbilical-hypersensitivity (n = 20). The posterior-only vestibular tenderness group included either women with a constricting hymenal-ring (n = 37) or with pelvic floor hypertonicity (n = 35). Interestingly, pain evoked during intercourse did not differ between groups. Linear regression analyses revealed augmented coital pain experience, umbilical-hypersensitivity and vestibular atrophy predicted enhanced pain hypersensitivity evoked at the anterior, but not at the posterior vestibule (R = 0.497, p < 0.001). Distinguishing tactile hypersensitivity in anterior and posterior vestibule and recognition of additional nociceptive markers can lead to clinical subgrouping.

Strength Exercise Has Different Effects on Pressure Pain Thresholds in Women with Endometriosis-Related Symptoms and Healthy Controls: A Quasi-experimental Study.

To evaluate the influence of strength exercises on remote pain sensitivity in women with endometriosis-related symptoms. A quasi-experimental study. University Hospital, a tertiary health unit. Twenty-one women with endometriosis-related symptoms and 21 healthy women provided written informed consent. The participants performed weekly exercise sessions on an extensor chair for four consecutive weeks. An electronic algometer was used to measure the pressure pain thresholds on the nondominant forearm. Heart rate and blood pressure were measured using a digital device. All measurements were taken before, immediately after, and 10 and 20 minutes after the exercise series. Women with endometriosis-related symptoms had lower pain thresholds. Pressure pain thresholds increased immediately after exercise in healthy women, returning to baseline level 20 minutes after exercise. Women with endometriosis-related symptoms did not present significant pressure pain threshold alterations after exercise. However, they had a higher heart rate and systolic, diastolic, and average blood pressure than healthy women at all the timepoints. There were no consistent correlations between pressure pain thresholds and heart rate or blood pressure. The strength exercise regimen used in this study increased pain thresholds in healthy women but not in women with endometriosis-related painful symptoms. The maintenance or even worsening of pain perception after exercise in women with persistent pain, such as those with endometriosis, may limit their adherence to a physical training program, which in turn could prevent them from experiencing the long-term beneficial effects of exercise.

Associations between pain thresholds for heat, cold and pressure, and Pain Sensitivity Questionnaire scores in healthy women and in women with persistent pelvic pain.

The Pain Sensitivity Questionnaire (PSQ) is a self-rating instrument developed as a time- and cost-saving alternative to quantitative sensory testing (QST). The aims of the study were to assess (a) the associations between PSQ scores and QST in women with persistent pelvic pain and in pain-free controls and (b) to what extent demographic variables and psychological distress influenced PSQ scores. Fifty-five healthy women and 37 women with persistent pelvic pain participated. All filled in the PSQ and Hospital Anxiety and Depression Scale and had QST (heat, cold and pressure pain thresholds) performed on six locations on the body. Information on age, body mass index, smoking habits and pain duration were collected. Principal component analysis and orthogonal partial least square regressions were used. The patients scored significantly higher on PSQ than the controls. Significant multivariate correlations between pain thresholds and PSQ scores were found only in the patient group. In the patient group, the heat and cold pain thresholds correlated more strongly with PSQ scores than the pressure pain threshold. The PSQ score was significantly higher in pelvic pain patients, and correlations between QSTs and the PSQ were only found for patients. The PSQ reflects pain sensitivity in women with PPP and can be used as a non-invasive and painless way to assess this condition in clinical practice.

Active Trigger Points Are Associated With Anxiety and Widespread Pressure Pain Sensitivity in Women, but not Men, With Tension Type Headache.

A better understanding of gender differences can assist clinicians in further developing therapeutic programs in tension type headache (TTH). To evaluate gender differences in the presence of trigger points (TrPs) in the head, neck, and shoulder muscles and their relationship with headache features, pressure pain sensitivity, and anxiety in people with TTH. Two hundred and ten (59 men, 151 women) patients with TTH participated. TrPs were bilaterally explored in the temporalis, masseter, suboccipital, upper trapezius, splenius capitis, and sternocleidomastoid muscles. Headache features were collected using a 4-week headache diary. Trait and state anxiety levels were assessed using the State-Trait Anxiety Inventory. Pressure pain thresholds (PPTs) over the temporalis, C5/C6 joint, second metacarpal, and tibialis anterior were assessed. Women with TTH exhibited a significantly higher number of total (P = 0.027) and active (P = 0.030), but similar number of latent (P = 0.461), TrPs than men with TTH. Active TrPs in the temporalis, suboccipital, and splenius capitis muscles were the most prevalent in both men and women with TTH. The number of active TrPs was associated with anxiety levels (r = 0.217; P = 0.045) in women, but not in men (P = 0.453): the higher the number of active TrPs, the more the trait levels of anxiety. Women exhibited lower PPTs than men (all, P < 0.001). In men, the number of active, but not latent, TrPs was negatively associated with localized PPTs (all, P < 0.05), whereas in women, the number of active and latent TrPs was negatively associated with PPTs in all points (all, P < 0.01): the higher the number of TrPs, the lower the widespread PPTs. This study described gender differences in the presence of TrPs in TTH. Women with TTH showed lower PPTs than men. The association between TrPs, anxiety levels, and pressure pain hyperalgesia seems to be more pronounced in women than in men with TTH.

Catechol-O-Methyltransferase Val158Met Polymorphism Is Associated with Anxiety, Depression, and Widespread Pressure Pain Sensitivity in Women with Chronic, but Not Episodic, Migraine.

To analyze the association between the rs4680 catechol-O-methyltransferase Val158Met polymorphism and to determine the association of this polymorphism with clinical, psychological, and pain sensitivity variables in women with episodic or chronic migraine. Fifty women with episodic migraine, 50 with chronic migraine, and 50 matched healthy women participated. After amplifying the Val158Met polymorphism by polymerase chain reaction, we assessed genotype frequencies and allele distributions. Participants were classified according to the Val158Met polymorphism genotype into Val/Val, Val/Met, or Met/Met. A headache diary was used for collecting migraine pain features. Disability was assessed with the Migraine Disability Assessment Scale, trait/state anxiety levels with the State-Trait Anxiety Inventory, and depression/anxiety with the Hospital Anxiety and Depression Scale. Pressure pain thresholds (PPTs) were bilaterally assessed over the temporalis, the upper trapezius, the second metacarpal, and the tibialis anterior. The distribution of the rs4680 Val158Met genotype was not significantly different between women with and without migraine (P = 0.157). No differences in migraine features were found to be dependent on the Val158Met genotype. Women with the Met/Met genotype showed higher migraine-related disability than those with the Val/Val or Val/Met genotype in both migraine groups (P < 0.01). Women with chronic, but not episodic, migraine with the Met/Met genotype exhibited higher depressive and anxiety levels and lower PPTs than those with the Val/Val or Val/Met genotype. The Val158Met rs4680 polymorphism does not appear to be involved in predisposition to suffer from migraine; however, this genetic factor may be involved in the phenotypic expression of chronic migraine, as anxiety, depression, and widespread pressure pain sensitivity were greater in those women with chronic, but not episodic, migraine with the Met/Met genotype.

Perceived Pain Extent is Not Associated With Widespread Pressure Pain Sensitivity, Clinical Features, Related Disability, Anxiety, or Depression in Women With Episodic Migraine.

People with migraine present with varying pain extent and an expanded distribution of perceived pain may reflect central sensitization. The relationship between pain extent and clinical features, psychological outcomes, related disability, and pressure pain sensitivity in migraine has been poorly investigated. Our aim was to investigate whether the perceived pain extent, assessed from pain drawings, relates to measures of pressure pain sensitivity, clinical, psychological outcomes, and related disability in women with episodic migraine. A total of 72 women with episodic migraine completed pain drawings, which were subsequently digitized allowing pain extent to be calculated utilising novel software. Pressure pain thresholds were assessed bilaterally over the temporalis muscle (trigeminal area), the cervical spine (extratrigeminal area), and tibialis anterior muscle (distant pain-free area). Clinical features of migraine, migraine-related disability (migraine disability assessment questionnaire [MIDAS]), and anxiety and depression (Hospital Anxiety-Depression Scale [HADS]) were also assessed. Spearman ρ correlation coefficients were computed to reveal correlations between pain extent and the remaining outcomes. No significant associations were observed between pain extent and pressure pain thresholds in trigeminal, extratrigeminal or distant pain-free areas, migraine pain features, or psychological variables including anxiety or depression, and migraine-related disability. Pain extent within the trigeminocervical area was not associated with any of the measured clinical outcomes and not related to the degree of pressure pain sensitization in women with episodic migraine. Further research is needed to determine if the presence of expanded pain areas outside of the trigeminal area can play a relevant role in the sensitization processes in migraine.

Experimental pain sensitivity in women with vestibulodynia: a pilot study

Objective: Investigate pain sensitivity in women with vestibulodynia using two experimental pain assessments outside the vulvar region: intramuscular infusion of an acidic phosphate buffer and pressure pain thresholds (PPTs) of the lower limb. Methods: Three women with a history of vestibulodynia (all 24 years old) participated after providing written informed consent. PPTs of the lower limb were assessed using a hand-held Somedic digital algometer (30 kilopascal (kPa)/sec) at baseline (pre-infusion) and during the intramuscular infusion. The acidic phosphate buffer (pH 5.2) was infused into the anterior tibialis muscle at a rate of 40 ml/hr for 15 min (10 ml total). Peak local (infusion site) and referred (ankle) pain ratings were assessed verbally, as well as vulvar pain at the time of the infusion (0 – 10 Borg Scale). Results: Peak local pain was higher in two of the three subjects (2.5, 4.0, 9.5) than the average pain ratings in 34 healthy age-matched (21 – 27 years old) women from our laboratory, mean 3.0/10 (standard deviation (SD) 2.2; range 0.5 to 10). Peak referred pain was also higher in the same two subjects (0, 4.25, and 7.5) than the average of the controls (mean 1.5; SD 1.8; range 0 – 9.0). Similarly, vulvar pain patients all exhibited greater mechanical pain sensitivity (lower PPT values) than the average of the healthy controls (mean [SD] 246.3 [101.7] kPa in patients vs. 431.3 [109.33] in controls). Conclusion: Preliminary data suggests women with vestibulodynia may exhibit greater generalized pain sensitivity to noxious stimuli than the general population of women.

Pain extent is associated with pain intensity but not with widespread pressure or thermal pain sensitivity in women with fibromyalgia syndrome.

Widespread pain is considered a sign of central sensitization in people with chronic pain. Our aim was to examine whether pain extent, assessed from the pain drawing, relates to measures from quantitative sensory testing in fibromyalgia syndrome (FMS). Thirty women with FMS and no other co-morbid conditions completed pain drawings (dorsal and ventral views) and clinical and related disability questionnaires. Pain extent and pain frequency maps were obtained from the pain drawings using a novel customized software. Pressure pain thresholds were assessed over the 18 tender points considered by the 1990 American College of Rheumatology criteria for FMS diagnosis and over two additional standardized points. Heat and cold pain thresholds were also assessed on the dorsal aspect of the neck, the dorsal aspect of the wrist, and the tibialis anterior. Spearman's correlation coefficients were used to assess the relationship between pain extent and quantitative sensory testing outcomes as well as clinical symptoms. Larger extent of pain was associated with a higher pain intensity (dorsal area: r s=0.461, P=0.010; total area: r s=0.593, P=0.001), younger age (ventral area: r s=-0.544, P=0.002; total area: r s=-0.409, P=0.025), shorter history of pain (ventral area: r s=-0.367, P=0.046), and higher cold pain thresholds over the tibialis anterior muscle (r s=-0.406, P=0.001). No significant association was observed between pain extent and the remaining outcomes. Pain drawings constitute an easy and accurate approach to quantify widespread pain. Larger pain extent is associated with pain intensity but not with signs of central sensitization in women with FMS.

Patients in the Postpartum and Breast-feeding Period

Pain after childbirth is common. The incidence of chronic postpartum pain is rising and has been shown to have a negative impact on the mother, the baby, and the rest of the family. Estrogen heightens pain sensitivity in women, and high levels of estrogen are normally seen during pregnancy. In patients who have had a cesarean section, postpartum pain can be caused by several different factors, including pain at the point of incision, infection at the incision site, suture breakdown, tape burn, or collection of fluid under the skin. In addition to complications during a cesarean section, other complications can arise during childbirth that require the use of pain medications, and this can cause concern for mothers who are breast-feeding. This review outlines the types of complications that can occur in mothers after the delivery of a baby and the types of medications they are prescribed. Additionally, this review outlines which drugs are safe for the breast-feeding mother and baby as well as medications that should be used with caution.

Catechol-O-methyltransferase gene polymorphism and vulvar pain in women with vulvodynia

The underlying causes of vulvar pain in women with vulvodynia remain poorly understood. Catechol-O-methyltransferase, an enzyme that metabolizes catecholamines, is a neuromodulator that isinvolved with perception and sensitivity to pain. The catechol-O-methyltransferasegene is polymorphic, and a single nucleotide polymorphism is associated with low activity and heightened pain sensitivity. The variant allele that encodes this polymorphism commonly is called the "L allele" because of its low enzyme activity as opposed to the normal H (high activity) allele. The methionine-containing catechol-O-methyltransferase protein coded by the L allele results in elevated catecholamine levels, reduced inactivation of the dopaminergic and adrenergic systems, and increased sensitivity to pain. This polymorphism not only may decrease the pain threshold in response to acute pain but also may facilitate the development of chronic pain. Therefore, the objective of our study was to assess whether a variation in the catechol-O-methyltransferase genotype is involved in increased pain sensitivity in women with vulvodynia. We conducted a prospective cohort study. Buccal swabs were collected from 167 white women with vulvodynia and 107 control subjects; the DNA was tested for a single nucleotide polymorphism at position 158 (rs4680) in the catechol-O-methyltransferase gene. Women with vulvodynia had a marginally increased, yet not significant, prevalence of the catechol-O-methyltransferase genotype that is associated with high activity of the coded protein: 32.9% in the women with vulvodynia, as opposed to 21.5% in the control subjects (odds ratio, 1.80; 95% confidence interval, 1.02-3.15). Subgrouping the cases based on pain frequency revealed that the elevated occurrence of this catechol-O-methyltransferase genotype was present in 40.6% of the subset of women who experienced pain only with sexual intercourse vs only 21.5% of control subjects (odds ratio, 2.50; 95% confidence interval, 1.27-4.93). Also, women with primary vulvodynia had a significantly higher prevalence of the H allele than did the control subjects (62.9% vs 48.1%; odds ratio, 1.82; 95% confidence interval, 1.05-3.17). Increased pain sensitivity in women with vulvodynia is not due to a genetically determined low catechol-O-methyltransferaseenzyme activity. Other mechanisms may account for alterations in catechol-O-methyltransferase activity in women with pain that is limited to intercourse or primary vulvodynia that contributes to pain sensitivity.

Morning Versus Evening Bright Light Treatment at Home to Improve Function and Pain Sensitivity for Women with Fibromyalgia: A Pilot Study.

To test the feasibility, acceptability, and effects of a home-based morning versus evening bright light treatment on function and pain sensitivity in women with fibromyalgia. A single blind randomized study with two treatment arms: 6 days of a 1 hour morning light treatment or 6 days of a 1 hour evening light treatment. Function, pain sensitivity, and circadian timing were assessed before and after treatment. Participants slept at home, except for two nights in Sleep Center. Ten women meeting the American College of Rheumatology's diagnostic criteria for fibromyalgia, including normal blood test results. Self-reported function was assessed with the Fibromyalgia Impact Questionnaire (FIQ). Pain sensitivity was assessed using a heat stimulus that gave measures of threshold and tolerance. Circadian timing was assessed with the dim light melatonin onset. Both morning and evening light treatments led to improvements in function and pain sensitivity. However, only the morning light treatment led to a clinically meaningful improvement in function (>14% reduction from baseline FIQ) and morning light significantly increased pain threshold more than evening light ( P < 0.05). Phase advances in circadian timing were associated with an increase in pain tolerance (r = 0.67, P < 0.05). Bright light treatment appears to be a feasible and acceptable adjunctive treatment to women with fibromyalgia. Those who undergo morning light treatment may show improvements in function and pain sensitivity. Advances in circadian timing may be one mechanism by which morning light improves pain sensitivity. Findings can inform the design of a randomized controlled trial.

Women with dysmenorrhoea are hypersensitive to experimentally induced forearm ischaemia during painful menstruation and during the pain-free follicular phase.

Monthly primary dysmenorrhoeic pain is associated with increased sensitivity to painful stimuli, particularly in deep tissue. We investigated whether women with dysmenorrhoea, compared with controls, have increased sensitivity to experimentally induced deep-tissue muscle ischaemia in a body area distant from that of referred menstrual pain. The sub-maximal effort tourniquet test was used to induce forearm ischaemia in 11 women with severe dysmenorrhoea and in nine control women both during menstruation and in the follicular phase of the menstrual cycle. Von Frey hair assessments confirmed the presence of experimental ischaemia. Women rated the intensity of menstrual and ischaemic pain on a 100-mm visual analogue scale. Women with dysmenorrhoea [mean (SD): 68 (20) mm] reported significantly greater menstrual pain compared with controls [mean (SD): 2 (6) mm; p = 0.0001] during the menstruation phase. They also rated their forearm ischaemic pain as significantly greater than the controls during the menstruation [dysmenorrhoeics vs. controls mean (SD): 58 (19) mm vs. 31 (21) mm, p < 0.01] and follicular [dysmenorrhoeics vs. controls mean (SD): 60 (18) mm vs. 40 (14) mm, p < 0.01] phases of the menstrual cycle. These data show that compared with controls, women who experience severe recurrent dysmenorrhoea have deep-tissue hyperalgesia to ischaemic pain in muscles outside of the referred area of menstrual pain both during the painful menstruation phase and pain-free follicular phase. These findings suggest the presence of long-lasting changes in muscle pain sensitivity in women with dysmenorrhoea. Our findings that dysmenorrhoeic women are hyperalgesic to a clinically relevant, deep-muscle ischaemic pain in areas outside of referred menstrual pain confirm other studies showing long-lasting changes in pain sensitivity outside of the painful period during menstruation.