Sex and gender differences in pain: a selective review of biological and psychosocial factors

Evidence suggests that there are important differences between men and women with respect to the perception and experience of pain. The objective of this review is to provide a general overview of this area and to explore potential mechanisms for such differences. It will focus on a range of different types of evidence including experimental studies, epidemiology, as well as more clinically orientated treatment investigations. Some of the biological, psychological and social factors thought to help understand why such variation between men and women occurs will be considered. While there are still many unanswered questions, what is clear is that it is no longer acceptable to simply ignore such potentially important differences between the sexes in their experience of pain.     

绝经后女性内源性性激素及血脂水平与乳腺癌的关系

目的:探讨绝经后女性内源性性激素及血脂水平与乳腺癌的关系以及作为预测指标的可行性。方法:收集2011年7月—2014年6月期间手术治疗的绝经后女性乳腺癌患者274例(乳腺癌组)与同期因其他疾病收治的非乳腺疾病的绝经后患者279例(对照组);比较两组间性激素与血脂水平的差异,分析可能的乳腺癌预测指标。结果:乳腺癌组的雌二醇(E2)与睾酮(T)水平明显高于对照组(均P0.05),其他性激素与血脂指标两组间差异均无统计学意义(均P0.05)。分层分析显示,随E2与T水平升高,乳腺癌发病率增加,其中E2水平对乳腺癌的预测有较好的敏感性和特异性,受试者操作特征(ROC)曲线下面积(AUC)为0.730(95%CI=0.649~0.811),但T水平的预测作用不明显。结论:E2与T水平与绝经后女性乳腺癌有关,其中E2水平可作为预测因子之一,但尚未达到良好或者优秀标准。     

无精症患者的遗传因素与性激素水平的临床分析

目的:探讨无精症患者的遗传因素与性激素水平的关系。方法:选取本院2015年7月至2019年9月被确诊为无精症的113例患者作为试验组,30例精子数量正常人作为对照组,分别进行外周血染色体核型、Y染色体AZF微缺失以及性激素检测。结果:在113例无精症患者中检出染色体异常核型36例(31.9%),异常核型具体如下：47,...     

性别因素对福尔马林诱导大鼠伤害性感受的影响

目的 探讨性别因素对福尔马林诱导大鼠伤害性感受的影响。方法 14周龄SD大鼠16只，按性别分为2组，雌性组（n=7）体重250-270 g，雄性组（n=9）体重330-350 g。测定基础热痛阈（PWL）、基础机械痛阈（PWT）和福尔马林诱导伤害性感受的行为学评分。注射福尔马林后60 min分为3个时段：0-10 min为急性疼痛期（时相Ⅰ）;10-20 min为间期;20-60 min为疼痛晚期（时相Ⅱ）。计算各时段行为学的综合评分。结果 2组PWL、PWT比较差异无统计学意义（P〉0．05）。与雄性组比较，雌性组注射福尔马林后0-5min痉挛次数增多（P〈0．01），在时相Ⅱ时行为学综合评分升高（P〈0．05），时相Ⅰ及间期差异无统计学意义（P〉0．05）。结论 大鼠对福尔马林诱导的伤害性感受存在性别差异，提示性激素可能在伤害性感受中起着一定的调节作用。     

Experimental Pain Models Reveal No Sex Differences in Pentazocine Analgesia in Humans

Background: Accumulating evidence suggests that there are sex differences in analgesic responses to opioid agonists. Several studies using an oral surgery pain model have reported more robust analgesia to [kappa]-agonist-antagonists (e.g., pentazocine, nalbuphine, butorphanol) among women than among men. However, evidence of sex differences in [kappa]-agonist-antagonist effects from studies of experimentally induced pain in humans is lacking.

Methods: Therefore, the analgesic effects of intravenous pentazocine (0.5 mg/kg) were determined in healthy women (n = 41) and men (n = 38) using three experimental pain models: heat pain, pressure pain, and ischemic pain. Each pain procedure was conducted before and after double-blind administration of both pentazocine and saline, which occurred on separate days in counterbalanced order.

Results: Compared with saline, pentazocine produced significant analgesic responses for all pain stimuli. However, no sex differences in pentazocine analgesia emerged. Effect sizes for the sex differences were computed; the magnitude of effects was small, and an equal number of measures showed greater analgesia in men than in women. Also, analgesic responses were not highly correlated across pain modalities, suggesting that different mechanisms may underlie analgesia for disparate types of pain.     

Alfentanil and Placebo Analgesia: No Sex Differences Detected in Models of Experimental Pain

Background: To assess whether patient sex contributes to the interindividual variability in alfentanil analgesic sensitivity, the authors compared male and female subjects for pain sensitivity after alfentanil using a pharmacokinetic-pharmacodynamic modeling approach.

Methods: Healthy volunteers received a 30-min alfentanil or placebo infusion on two occasions. Analgesia was measured during the subsequent 6 h by assaying tolerance to transcutaneous electrical stimulation (eight men and eight women) of increasing intensity or using visual analog scale scores during treatment with noxious thermal heat (five men and five women). Sedation was concomitantly measured. Population pharmacokinetic-pharmacodynamic models were applied to the analgesia and sedation data using NONMEM. For electrical pain, the placebo and alfentanil models were combined post hoc.

Results: Alfentanil and placebo analgesic responses did not differ between sexes. The placebo effect was successfully incorporated into the alfentanil pharmacokinetic-pharmacodynamic model and was responsible for 20% of the potency of alfentanil. However, the placebo effect did not contribute to the analgesic response variability. The pharmacokinetic-pharmacodynamic analysis of the electrical and heat pain data yielded similar values for the potency parameter, but the blood-effect site equilibration half-life was significantly longer for electrical pain (7-9 min) than for heat pain (0.2 min) or sedation (2 min).     

Analgesia and respiratory function following intrapleural bupivacaine after cholecystectomy

Analgesia and pulmonary function following intrapleural bupivacaine were compared with those following intramuscular pethidine in thirty-four patients after cholecystectomy. The patients were randomly allocated to two groups of seventeen patients each to receive either intrapleural bupivacaine or intramuscular pethidine. The positions of seventeen intrapleural catheters inserted were confirmed by chest radiography. Two out of seventeen catheters were found to be located in the extrapleural space. It was also recognized by fluoroscopy that phrenic nerve palsy did not develop on patients given intrapleural bupivacaine. The subjective quality of analgesia following intrapleural bupivacaine was significantly better than that following intramuscular pethidine. The mean duration of analgesia obtained after each injection of bupivacaine was 4.68hr (range 3.5–6.1hr). Forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV 1), which decreased markedly in the postoperative period improved significantly after being given bupivacaine or pethidine. But there was no significant difference in the improvement of FVC and FEV 1, between both groups in spite of the higher percentage of pain relief in the intrapleural bupivacaine group. All respiratory function tests studied thirty days after surgery were not significantly different when compared with those before surgery.(Lee TL, Boey WK, Jan WC: Analgesia and respiratory function following intrapleural bupivacaine after cholecystectomy. J Anesth 4: 20–28, 1990)     

Sex hormones,their receptors and bone health

Sex steroids regulate skeletal maturation and preservation in both men and women, as already recognized in the 1940s by Albright and Reifenstein. The impact of gonadal insufficiency on skeletal integrity has been widely recognized in adult men and women ever since. In the context of their skeletal actions, androgens and estrogens are no longer considered as just male and female hormones, respectively. Androgens can be converted into estrogens within the gonads and peripheral tissues and both are present in men and women, albeit in different concentrations. In the late 1980s, sex steroid receptors were discovered in bone cells. However, the understanding of sex steroid receptor activation and translation into biological skeletal actions is still incomplete. Due to the complex metabolism, sex steroids may have not only endocrine but also paracrine and/or autocrine actions. Also, circulating sex steroid concentrations do not necessarily reflect their biological activity due to strong binding to sex hormone binding globulin (SHBG). Finally, sex steroid signaling may include genomic and non-genomic effects in bone and non-bone cells. This review will focus on our current understanding of gonadal steroid metabolism, receptor activation, and their most relevant cellular and biological actions on bone.     

Can brief measures effectively screen for pain and somatic malingering? Examination of the Modified Somatic Perception Questionnaire and Pain Disability Index

Background contextRecent rise in fraudulent disability claims in the United States has resulted in psychologists being increasingly called upon to use psychological tests to determine whether disability claims based on psychological or somatic/pain complaints are legitimate.PurposeTo examine two brief measures, Modified Somatic Perception Questionnaire (MSPQ) and the Pain Disability Index (PDI), and their ability to screen for malingering in relation to the Bianchini et al. criteria for malingered pain-related disability published in The Spine Journal (2005).Study designExamined brief self-report measures between litigating and nonlitigating pain samples.Patient sampleWe compared 144 disability litigants, predominantly presenting a history of musculoskeletal injuries with psychiatric overlay, with 167 nonlitigating pain patients who were predominantly in treatment for chronic back pain issues and other musculoskeletal conditions.Outcome measuresModified Somatic Perception Questionnaire, Pain Disability Index, Minnesota Multiphasic Personality Inventory-2 Restructured Form, Test of Memory Malingering, Letter Memory Test, Victoria Symptom Validity Test, Structured Interview of Reported Symptoms-second edition, Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders somatoform disorders module.MethodsWe examined a sample of 144 individuals undergoing compensation-seeking evaluations in relation to 167 nonlitigating pain patients.ResultsGroup differences on both the MSPQ and PDI were calculated, as well as sensitivities, specificities, and positive and negative predictive powers for both measures at selected cutoffs.ConclusionsThe results suggest that both the MSPQ and PDI are useful to screen for pain malingering in forensic evaluations, especially the MSPQ, which performed the best in differentiating between the groups.     

曲马多超前镇痛对妇科腹腔镜手术术后疼痛影响的前瞻性随机对照研究

目的观察曲马多超前镇痛在妇科腹腔镜手术中的有效性及安全性。方法 2010年1月~6月,选择60例ASAⅠ~Ⅱ级全麻下行妇科腹腔镜手术病例,采用随机数字表法分为2组,每组30例。手术切皮前5 min实验组静注曲马多1.5 mg/kg,对照组静注生理盐水2 ml。观察术后苏醒时间,随访24 h VAS疼痛评分及Ram say镇静评分,镇痛药使用情况及不良反应发生情况等。结果 2组麻醉苏醒时间差异无显著性（P〉0.05）。与对照组相比,实验组术后12 h内VAS评分显著降低[术后1 h 1.50±1.76 vs.4.03±2.50,t=4.544,P=0.000;术后2 h 1.77±1.87 vs.4.47±2.67,t=4.532,P=0.000;术后4 h 1.63±1.40 vs.3.20±2.00,t=3.506,P=0.001;术后8 h 1.83±1.76 vs.2.80±1.85,t=2.074,P=0.043;术后12 h1.50±1.25 vs.2.30±1.66,t=2.104,P=0.040],术后镇痛药的应用明显减少（1例vs.7例,2χ=5.192,P=0.023）,副反应中仅头晕的发生例数较多（6例vs.1例,2χ=4.043,P=0.044）。2组Ram say镇静评分均为1~2分。结论妇科腹腔镜全麻术前静注曲马多1.5 mg/kg可有效缓解术后疼痛,减少辅助镇痛药用量,副作用较少,是临床上较好的镇痛方法。     

健康成人血清胱抑素C与增龄关系的探讨

目的：探讨血清胱抑素C（CysC）在健康成人中的变化。方法：以随机整群抽样方式在北京15个社区抽取健康成人396例,其中男160例,女236例,年龄30岁～99岁。血清CysC用增强散射比浊法（PENIA）测定。5年后随访,复查上述检查,随访252例,男99例,女153例,年龄35岁～89岁,并用双血浆法测定肾小球滤过率（GFR）。结果：横断面分析显示老年组（≥65岁）血清CysC高于青年组（〈65岁）（P〈0.01）。10岁年龄段分层分析,50岁以下血清CysC浓度男性高于女性。纵向分析5年后血清CysC较5年前升高（P〈0.05）。CysC与年龄呈正相关（r=0.551,P〈0.01）、与GFR呈负相关（r=-0.555,P〈0.01）;多元线性回归分析发现年龄、GFR、腰臀比、总胆固醇是血清CysC的独立相关因素。结论：健康人血清CysC随年龄增加而升高,而且在30岁～50岁具有性别差异。血清CysC升高不仅仅由肾功能减退所致。腰臀比、尿酸也是血清CysC的独立相关因素。     

性分化异常患者分子病因学研究

为探讨ＳＲＹ基因在睾丸决定和分化中的作用，对２例４６，ＸＸ真两性畸形、１例４６，ＸＹ女性、１例４６，ＸＹ女性伴男女难分患者系统地进行了临床、内分泌学、剖腹探查及病理组织学研究，并应用ＰＣＲ和Ｓｏｕｔｈｅｒｎｂｌｏｔ技术对４例个体基因组ＤＮＡ（ｇＤＮＡ）中ＳＲＹ基因作分子生物学分析。结果发现４例性分化异常患者ｇＤＮＡ中ＳＲＹ基因缺失突变。认为ＳＲＹ基因是参与睾丸决定和分化的关键调控基因。     

Efficacy of triamcinolone acetonide and bupivacaine for pain after lumbar discectomy

The study is a prospective blinded randomised controlled trial to compare the efficacy of triamcinolone acetonide, bupivacaine or in combination in managing pain after lumbar discectomy. Patients undergoing primary single-level lumbar discectomy were randomised. Triamcinolone acetonide, bupivacaine or in combination was instilled at the nerve root as decompression. Preoperative, day 1 and 6 weeks pain score, 24-h postoperative opiate requirements and duration of inpatient stay were recorded. Data was analysed using Mann–Whitney test for statistical significance. 100 patients were recruited. A significant difference was noted in day one postoperative mean pain score, mean 24-h opiate requirement and mean inpatient stay in the triamcinolone acetonide and bupivacaine group. At 8 weeks postoperatively, no significant differences were seen in the pain score in all groups. Significant postoperative pain reduction and opiate requirements in the first 24 h, and significantly shortened duration of inpatient stay were achieved in the triamcinolone acetonide and bupivacaine group compared with other groups.     

盐酸乙哌立松治疗颈肩痛腰背痛临床疗效评价

目的 :评价盐酸乙哌立松对骨科常见痛症的临床疗效。方法 :由 7家医院同时收集了采用单独口服盐酸乙哌立松和加用其他药物两种方法治疗的 13 8例患者 ,记录两组的治疗效果和副作用。结果 :对于颈肩痛和腰背痛等疾病的常见症状 ,单一组和联合组均可取得 80 %以上的有效率。病情轻者单一组即可取得良好疗效 ,病情重者联合组效果更好 ,但两组间无统计学差异。副作用发生率为 1.45 %。结论 :单独应用盐酸乙哌立松就可获得很高的有效率 ,与其他药物联合服用 ,可使其有效率进一步提高。盐酸乙哌立松的安全性很好 ,副作用发生率低。