Examining sex differences in knee pain: the multicenter osteoarthritis study

OBJECTIVE

To determine whether women experience greater knee pain severity than men at equivalent levels of radiographic knee osteoarthritis (OA).

DESIGN AND METHODS

A cross-sectional analysis of 2712 individuals (60% women) without knee replacement or a recent steroid injection. Sex differences in pain severity at each Kellgren-Lawrence (KL) grade were assessed by knee using visual analog scale (VAS) scale and Western Ontario and McMaster Universities Arthritis Index (WOMAC) with and without adjustment for age, analgesic use, Body mass index (BMI), clinic site, comorbid conditions, depression score, education, race, and widespread pain (WSP) using generalized estimating equations. Effect sizes (Cohen's d) were also calculated. Analyses were repeated in those with and without patellofemoral OA (PFOA).

RESULTS

Women reported higher VAS pain at all KL grades in unadjusted analyses (d = 0.21-0.31, P < 0.0001-0.0038) and in analyses adjusted for all covariates except WSP (d = 0.16-0.22, P < 0.0001-0.0472). Pain severity differences further decreased with adjustment for WSP (d = 0.10-0.18) and were significant for KL grade ≤2 (P = 0.0015) and 2 (P = 0.0200). Presence compared with absence of WSP was associated with significantly greater knee pain at all KL grades (d = 0.32-0.52, P < 0.0001-0.0008). In knees with PFOA, VAS pain severity sex differences were greater at each KL grade (d = 0.45-0.62, P = 0.0006-0.0030) and remained significant for all KL grades in adjusted analyses (d = 0.31-0.57, P = 0.0013-0.0361). Results using WOMAC were similar.

CONCLUSIONS

Women reported greater knee pain than men regardless of KL grade, though effect sizes were generally small. These differences increased in the presence of PFOA. The strong contribution of WSP to sex differences in knee pain suggests that central sensitivity plays a role in these differences.

Association of pain with HbA1c in a predominantly black population of community-dwelling adults with diabetes: a cross-sectional analysis

AIMS

To assess the relationship between pain and HbA(1c) levels in a predominantly black population with diabetes, and to determine whether self-management behaviours (exercise and diet) and symptoms of depression mediate this relationship.

METHODS

We analysed cross-sectional data from 417 community-dwelling individuals with diabetes in rural Alabama, USA. Binary logistic regression was used to analyse the relationship between pain and HbA(1c) levels, defined as relatively good [≤ 64 mmol/mol (≤ 8.0%)] and relatively poor [> 64 mmol/mol (> 8.0%)], after adjusting for sociodemographics, insulin use, medication count, cigarette smoking history and body mass index (BMI). We examined the mediating roles of exercise, diet, and symptoms of depression using bootstrapping.

RESULTS

Participants were primarily black (86.6%), female (76.1%) and reported an annual income of ≤$20,000 (52.7%). Their mean (sd) age was 59.6 (12.8) years. The majority of the participants reported moderate to extreme pain (71.5%). Participants reporting pain were more than twice as likely to have HbA(1c) levels > 64 mmol/mol (8.0%) in the fully adjusted model (odds ratio 2.33 [95% CI 1.28-4.24]; P < 0.05). Diet significantly mediated the relationship between pain and HbA(1c) control (β = 0.06; 95% CI: 0.01-0.17), but only in the unadjusted model. Exercise and symptoms of depression were not significant mediators.

CONCLUSIONS

A significant independent relationship between pain and HbA(1c) control was found in this mainly black population, which was not explained by self-management behaviours or symptoms of depression. Future research is needed to delineate the mechanism by which pain influences HbA(1c) control, especially among black people with diabetes on low incomes.

Vitamin D, race, and experimental pain sensitivity in older adults with knee osteoarthritis

OBJECTIVE

Low circulating serum levels of 25-hydroxyvitamin D (referred to hereafter as vitamin D) have been correlated with many health conditions, including chronic pain. Recent clinical practice guidelines define vitamin D levels <20 ng/ml as deficient and levels of 21-29 ng/ml as insufficient. Vitamin D insufficiency, including the most severe levels of deficiency, is more prevalent in black Americans. Ethnic and race group differences have been reported in both clinical and experimental pain, with black Americans reporting increased pain. The purpose of this study was to examine whether variations in vitamin D levels contribute to race differences in knee osteoarthritis pain.

METHODS

The sample consisted of 94 participants (74% women), including 45 blacks and 49 whites with symptomatic knee osteoarthritis. Their average age was 55.8 years (range 45-71 years). Participants completed a questionnaire on knee osteoarthritis symptoms and underwent quantitative sensory testing, including measures of sensitivity to heat-induced and mechanically induced pain.

RESULTS

Blacks had significantly lower levels of vitamin D compared to whites, demonstrated greater clinical pain, and showed greater sensitivity to heat-induced and mechanically induced pain. Low levels of vitamin D predicted increased experimental pain sensitivity, but did not predict self-reported clinical pain. Group differences in vitamin D levels significantly predicted group differences in heat pain and pressure pain thresholds at the index knee and ipsilateral forearm.

CONCLUSION

These data demonstrate that race differences in experimental pain are mediated by differences in the vitamin D level. Vitamin D deficiency may be a risk factor for increased knee osteoarthritis pain in black Americans.

Effects of "Favorability" and Type of Assessment Device Upon Acceptance of General Personality Interpretations

College students' acceptance of general personality interpretations was evaluated as a function of type of test and assessment device employed and interpretation favorability. Unlike previous studies, only interpretation favorability influenced acceptance. The effect of interpretation favorability upon acceptance, however, was shown to be due to the higher base-rate accuracy of favorable, relative to unfavorable, interpretations. It was concluded that the universal validity of general interpretations may supersede the effects of situational factors upon acceptance.

Health-related direct-to-consumer genetic tests: a public health assessment and analysis of practices related to Internet-based tests for risk of thrombosis

BACKGROUND

Recent years have seen increased concern about direct-to-consumer (DTC) genetic testing (i.e., the sale and use of genetic tests without involving a health care provider). Numerous professional organizations have developed policies in this area. However, little systematic evidence exists to inform public policy about these tests.

METHODS

We conducted a systematic search to identify genetic tests that are sold DTC without involving a health care provider. We evaluated the practices of companies offering DTC genetic tests for risk of thrombosis using criteria from multiple sources and a minimal set of key practices.

RESULTS

We identified 84 instances of currently available health-related DTC genetic tests sold on 27 Web sites; the most common were for pharmacogenomics (12), risk of thrombosis (10), and nutrigenomics (10). For the DTC genetic tests for risk of thrombosis, we found low adherence to recommendations. Online information was frequently incomplete and had low agreement with professional recommendations.

CONCLUSION

Our findings document the rapid growth in the availability of health-related DTC genetic tests and highlight the need to improve the delivery of DTC genetic tests. A major implication of this study is the need for the scientific and medical community to develop consistent recommendations to increase their impact.

Increased DNA fragmentation and ultrastructural changes in fibromyalgic muscle fibres

OBJECTIVE

To determine whether there is evidence of increased DNA fragmentation and ultrastructural changes in muscle tissue of patients with fibromyalgia (FM) compared with healthy controls.

METHODS

Muscle tissues from 10 community residents with FM and 10 age and sex matched healthy controls were examined "blindly" for the presence of DNA fragmentation by two different methods: terminal deoxynucleotidyl transferase (TdT) staining (TUNEL) and the FragEL-Klenow DNA fragmentation detection kit. Ultrastructural analysis of tissue was performed by electron microscopy.

RESULTS

DNA fragmentation was detected by both methods in 55.4 (SEM 2.5)% of the nuclei in muscle tissue of patients with FM compared with 16.1 (4.1)% (p<0.001) of the nuclei in healthy controls. Contrary to expectation, no typical features of apoptosis could be detected by electron microscopy. The myofibres and actin filaments were disorganised and lipofuscin bodies were seen; glycogen and lipid accumulation were also found. The number of mitochondria was significantly lower in patients with FM than in controls and seemed to be morphologically altered.

CONCLUSION

The ultrastructural changes described suggest that patients with FM are characterised by abnormalities in muscle tissue that include increased DNA fragmentation and changes in the number and size of mitochondria. These cellular changes are not signs of apoptosis. Persistent focal contractions in muscle may contribute to ultrastructural tissue abnormalities as well as to the induction and/or chronicity of nociceptive transmission from muscle to the central nervous system.

Assigning risk for Smith-Lemli-Opitz syndrome as part of 2nd trimester screening for Down's syndrome

OBJECTIVES

To design a reliable model in the context of prenatal screening for assigning the risk in an individual pregnancy of Smith-Lemli-Opitz syndrome (SLOS) and assess its performance.

SETTING

A 2nd trimester screening programme for Down's syndrome that measures unconjugated estriol (uE3) along with other serum markers.

METHODS

Development of individual risk estimates with a trivariate model incorporating measurements of maternal serum uE3, alpha-fetoprotein (AFP), and human chorionic gonadotropin (hCG) in both SLOS and unaffected pregnancies.

RESULTS

Population parameters were computed for the three analytes, as were pairwise correlation coefficients and truncation limits, based on an unbiased collection of 29 affected pregnancies. Published parameters were used for unaffected pregnancies. With a cut off level of risk of 1:50, 62% of SLOS pregnancies can be detected by initially identifying 0.34% of unaffected pregnancies as screen positive. About 1 in 90 screen positive pregnancies will be affected.

CONCLUSIONS

It is possible to screen for SLOS as an add on to existing 2nd trimester maternal serum screening, if uE3 is already being measured. A large, prospective trial is necessary to determine whether diagnostic testing can be performed in maternal urine or serum rather than amniotic fluid.

Pain complaints in patients with fibromyalgia versus chronic fatigue syndrome

Individuals with fibromyalgia (FM) and/or chronic fatigue syndrome (CFS) report arthralgias and myalgias. However, only persons with FM alone exhibit abnormal pain responses to mild levels of stimulation, or allodynia. We identify the abnormalities in the neuroendocrine axes that are common to FM and CFS as well as the abnormalities in central neuropeptide levels and functional brain activity that differentiate these disorders. These two sets of factors, respectively, may account for the similarities and differences in the pain experiences of persons with FM and CFS.

Psychosocial and health status variables independently predict health care seeking in fibromyalgia

OBJECTIVE

To determine whether variables derived from the self-regulatory model of health and illness behavior accurately predict status as a patient or nonpatient with fibromyalgia (FM).

METHODS

Subjects were 79 patients who met American College of Rheumatology (ACR) criteria for FM and 39 community residents who met ACR criteria for FM but had not sought medical care for their symptoms (nonpatients). Subjects were administered 14 measures that produced 6 domains of variables: background demographics and pain duration; psychiatric morbidity; and personality, environmental, cognitive, and health status factors. These domains were entered in 4 different hierarchical logistic regression analyses to predict status as patient or nonpatient.

RESULTS

The full regression model was statistically significant (P < 0.0001) and correctly identified 90.7% of the subjects with a sensitivity of 92.4% and a specificity of 87.2%. The best individual predictors of group status were self-reports of self-efficacy, negative affect, recent stressful events, and perceived pain. Relative to nonpatients, patients reported higher levels of negative affect and perceived pain and a greater number of recent stressful experiences, as well as lower levels of self-efficacy.

CONCLUSION

Consistent with the self-regulatory model of health and illness behavior, psychosocial and health status variables predict health care-seeking behavior in persons with FM independently of background demographics and psychiatric morbidity. These variables may influence the severity of symptoms experienced by persons with this disorder as well as their health care-seeking behavior, but they are not necessary to produce abnormal pain sensitivity in FM.

Theoretical perspectives on the relation between catastrophizing and pain

The tendency to "catastrophize" during painful stimulation contributes to more intense pain experience and increased emotional distress. Catastrophizing has been broadly conceived as an exaggerated negative "mental set" brought to bear during painful experiences. Although findings have been consistent in showing a relation between catastrophizing and pain, research in this area has proceeded in the relative absence of a guiding theoretical framework. This article reviews the literature on the relation between catastrophizing and pain and examines the relative strengths and limitations of different theoretical models that could be advanced to account for the pattern of available findings. The article evaluates the explanatory power of a schema activation model, an appraisal model, an attention model, and a communal coping model of pain perception. It is suggested that catastrophizing might best be viewed from the perspective of hierarchical levels of analysis, where social factors and social goals may play a role in the development and maintenance of catastrophizing, whereas appraisal-related processes may point to the mechanisms that link catastrophizing to pain experience. Directions for future research are suggested.

Expression of the precursor of secretoneurin, secretogranin II, in the synovium of patients with rheumatoid arthritis and osteoarthritis

OBJECTIVE

Secretoneurin (SN) is a neuropeptide that is chemotactic for mononuclear cells and it has been suggested to be involved in the mediation of pain; there is also evidence that SN is involved in the inflammation process. As secretogranin II (SGII) is the precursor of SN, we investigated expression of SGII mRNA and SN protein in the synovium of patients with rheumatoid arthritis (RA) and osteoarthritis (OA).

METHODS

Snap frozen synovial tissue specimens from 12 patients with RA and 11 patients with OA were examined. RNA was isolated and cDNA copied by reverse transcription. The expression of SGII was determined by polymerase chain reaction and in situ hybridization (ISH). SGII expressing cells were compared with CD68 positive cells stained by immunohistochemistry. SN protein was also detected by immunohistochemistry.

RESULTS

A 524 bp SGII-specific fragment could be amplified by PCR from the cDNA of all specimens. ISH showed scattered expression of SGII in both RA and OA synovial tissue; its expression pattern was characterized by positive staining for SGII in both the lining and the sublining layer. Immunohistochemical double labeling with anti-CD68 antibodies revealed expression of SGII in CD68 negative, fibroblast-like cells, whereas CD68 positive macrophages did not. In RA and OA, the SGII staining by ISH was positive with a diffuse staining throughout the entire synovial tissue. SN protein expression was scattered in RA but more intense in OA synovium.

CONCLUSION

The expression of SGII mRNA in RA and OA synovial fibroblasts clearly supports the hypothesis that SN is involved in the synovial tissue inflammation in both diseases. The significant lower SN expression in RA could be due to an inhibitory mechanism with respect to the SN levels in synovial fluid. SN might be involved in the modulation of afferent nerve transmission and therefore might play a role in the sensation of pain, especially in patients with OA.

Use of neuroimaging to understand abnormal pain sensitivity in fibromyalgia

This paper examines the use of neuroimaging to measure change in regional cerebral blood flow (rCBF) produced by pain in patients with fibromyalgia and in healthy individuals. Fibromyalgia patients differ from healthy persons in rCBF distribution in several brain structures involved in pain processing and pain modulation both at rest and during experimental pain induction. These abnormalities may contribute to abnormal pain sensitivity as well as the maladaptive pain behaviors that characterize many patients with fibromyalgia. We anticipate that future neuroimaging studies will enhance our understanding of abnormal pain sensitivity and of pain management interventions aimed at altering central nervous system function in patients with fibromyalgia.

Screening for hereditary hemochromatosis: are DNA-based tests the answer?

Universal screening for hereditary hemochromatosis (HH) has been proposed by many experts, with understandable enthusiasm: HH can cause fatal complications, which are preventable with early treatment. The disorder involves excess iron accumulation that can result in tissue iron overload, with secondary cirrhosis, diabetes, heart failure, impotence and arthritis. These complications are preceded by years of iron accumulation, and most are believed to be preventable by removal of excess iron by phlebotomy. Thus, early identification and treatment - the quintessential functions of health screening - seem to make sense for HH. However, the available screening tests are imperfect. While they can identify many persons at increased risk from HH, the proportion that will develop serious clinical manifestations related to iron overload is not known with certainty. DNA-based tests do not provide a simple resolution to these questions.

A multiplex ARMS test for 10 cystic fibrosis (CF) mutations: evaluation in a prenatal CF screening program

In Maine, prenatal screening for cystic fibrosis (CF) is offered through primary care providers. Cheekbrush (buccal) samples are routinely tested for eight mutations by multiplex PCR amplification of five exons, followed by dot-blot hybridization with pooled allele-specific oligonucleotides (ASO). The ASO methodology is widely used and effective, but somewhat time and labor intensive when applied to CF carrier testing or couple-based prenatal screening in the general pregnant population. Amplification Refractory Mutation System (ARMS) is an improvement of the PCR that allows rapid detection of mutations involving single base changes or small deletions/insertions. In this study, two multiplex ARMS reactions are used to test for 10 common CF mutations. Clinical evaluation of the ARMS test includes a retrospective study of 140 banked samples (54 cell line, proficiency testing, and buccal controls; 86 clinical buccal samples) with known CF genotype (57 with CF mutations, 83 no mutation), followed by a prospective trial in which 309 buccal samples are analyzed con-currently using both methods. The success rate of the ARMS test in buccal lysates is comparable to the ASO method; all CF mutations are successfully identified. For testing nonsterile buccal lysates with low DNA concentrations, optimized performance in the ARMS method is obtained using Amplitaq Gold polymerase. The ARMS method developed is easy, rapid (1 day), and avoids the need for ASO probe labeling, dot-blotting and autoradiography. This study provides further evidence that ARMS methodology is suitable for clinical CF mutation analysis.

Issues in implementing prenatal screening for cystic fibrosis: results of a working conference

OBJECTIVE

To summarise a conference convened to examine how cystic fibrosis screening might appropriately be introduced into routine prenatal practice.

METHODS

Participants included experts from various relevant disciplines. Systematic reviews and data from individual trials were presented; issues were identified and discussed.

RESULTS

Judged by published criteria, prenatal cystic fibrosis screening is suitable for introduction. Screening can be performed cost effectively by identifying racial/ethnic groups at sufficient risk and then using either of two models for delivering laboratory services. Validated educational materials exist. Ethical issues are not unique.

CONCLUSIONS

Once adequate facilities for patient and provider education, testing, counselling, quality control, and monitoring are in place, individual programmes can begin prenatal screening for cystic fibrosis.

Antenatal therapy of Smith-Lemli-Opitz syndrome

OBJECTIVES

Smith-Lemli-Opitz syndrome (SLOS) is a recessively inherited disorder caused by an inborn error of cholesterol metabolism that results in deficiency of cholesterol and accumulation of the cholesterol precursor, 7-dehydrocholesterol (DHC) and its epimer, 8-DHC. Affected patients present with congenital anomalies, growth restriction, and mental retardation. Postnatal treatment with cholesterol supplementation has been shown to improve plasma sterol levels and has resulted in improved growth and development in many patients. We hypothesized that prenatal supplementation of cholesterol could potentially arrest some of the adverse consequences of cholesterol deficiency at an earlier stage of development.

METHODS

SLOS was diagnosed in the third trimester in a fetus initially identified by sonography with intrauterine growth restriction and ambiguous genitalia and confirmed by elevated levels of 7- and 8-DHC in amniotic fluid. Antenatal supplementation of cholesterol was provided by fetal intravenous and intraperitoneal transfusions of fresh frozen plasma (cholesterol level = 219 mg/dl).

RESULTS

The in utero transfusions resulted in increased levels of fetal cholesterol, as measured in blood samples obtained by cordocentesis. In addition, fetal red cell mean corpuscular volume rose, which further indicated that the exogenous cholesterol was incorporated into the fetal erythrocytes.

CONCLUSIONS

Antenatal treatment of SLOS by cholesterol supplementation is feasible and results in improvement in fetal plasma cholesterol levels and fetal red cell volume. SLOS may be added to the growing list of human genetic disorders for which prenatal diagnosis is available and therapeutic intervention may be possible.

Issues in implementing prenatal screening for cystic fibrosis: results of a working conference

PURPOSE

To summarize a conference convened to examine how cystic fibrosis screening might appropriately be introduced into routine prenatal practice.

METHODS

Participants included experts from various relevant disciplines. Systematic reviews and data from individual trials were presented; issues were identified and discussed.

RESULTS

Judged by published criteria, prenatal cystic fibrosis screening is suitable for introduction. Screening can be performed cost-effectively by identifying racial/ethnic groups at sufficient risk and then using either of two models for delivering laboratory services. Validated educational materials exist. Ethical issues are not unique.

CONCLUSIONS

Once adequate facilities for patient and provider education, testing, counseling, quality control, and monitoring are in place, individual programs can begin prenatal screening for cystic fibrosis.

Psychological and behavioral approaches to pain management for patients with rheumatic disease

This article reviews the efficacy of the psychological and behavioral pain management interventions that have been evaluated among adult patients with rheumatoid arthritis (RA), osteoarthritis (OA), and fibromyalgia (FM). Using published criteria for empirically validated interventions, it is concluded that cognitive-behavioral therapies and the Arthritis Self-Management Program represent well-established treatments for pain among patients with RA and OA. These interventions involve education, training in relaxation and other coping skills, and rehearsal of these skills in patients' home and work environments. There currently are no psychological or behavioral interventions for pain among FM patients that can be considered as well-established treatments. Future intervention research should use clinically meaningful change measures in addition to conventional tests of statistical significance, attend to the pain management needs of children, and assess whether outcomes produced in university-based treatment centers generalize to those in local treatment settings.

Immunohistochemical and molecular studies of serotonin, substance P, galanin, pituitary adenylyl cyclase-activating polypeptide, and secretoneurin in fibromyalgic muscle tissue

OBJECTIVE

Because former investigations have reported abnormal changes in the expression of serotonin (5-hydroxytryptamine [5-HT]) and substance P (SP) in serum and cerebrospinal fluid, this study sought to determine whether 5-HT and pain-modulating neuropeptides (SP, galanin [GA], pituitary adenylyl cyclase-activating polypeptide, and secretoneurin) were expressed abnormally in the muscle tissue of patients with fibromyalgia (FM).

METHODS

Snap-frozen muscle tissue specimens (deltoid muscles) from 10 patients with FM (mean disease duration 15 years) and from 10 healthy control subjects were examined by reverse transcriptase-polymerase chain reaction (RT-PCR) of RNA preparations from muscle cells, and by immunohistochemistry methods (alkaline phosphatase-anti-alkaline phosphatase and immunogold-silver) using specific primers as well as antibodies. When specific messenger RNA (mRNA) was detected by RT-PCR, in situ RT-PCR was performed for mRNA localization.

RESULTS

Specific mRNA for the examined substances was absent in 9 of 10 FM patients and in 10 of 10 controls. No differences between the FM patients and controls could be detected in the muscle tissue by immunohistochemistry. In 1 FM patient, mRNA for the GA receptor could be shown.

CONCLUSION

This study showed that 5-HT and neuropeptides are not produced in the muscle of patients with FM, and therefore do not appear to be involved in the peripheral induction of pain in this chronic, painful disorder.

Detecting sincerity of effort: a summary of methods and approaches

Despite the widespread use of methods that are supposed to detect the sincerity of patients' efforts in clinical assessment, little has been written summarizing the literature that addresses the reliability and validity of measurements obtained with these methods. The purpose of this article is to review the literature on the reliability and validity of scores for Waddell's nonorganic signs, descriptions of pain behavior and symptom magnification, coefficients of variation, correlations between musculoskeletal evaluation and function, grip measurements, and the relationship between heart rate and pain intensity. The authors of the articles reviewed conclude that none of these methods have been examined adequately. Some of these methods, such as Waddell's nonorganic signs, were not developed for the purpose of detecting sincerity of effort. Clinicians are encouraged to critically read the literature addressing these methods. With further research, some of the discussed methods may prove useful. Until such research is reported in the peer-reviewed literature, however, clinicians should avoid basing evaluation of sincerity of effort on these tests. Therapists are encouraged, instead, to use a biobehavioral approach to better understand and address the complex factors underlying delayed recovery.

Current concepts in the pathophysiology of abnormal pain perception in fibromyalgia

Fibromyalgia is a noninflammatory rheumatic disorder characterized by chronic widespread musculoskeletal pain. Although many studies have described the pain and other clinical symptoms associated with this disorder, the primary mechanisms underlying the etiology of fibromyalgia remain elusive. This article reviews recent data supporting the links among each of three systems--the musculoskeletal system, the neuroendocrine system, and the central nervous system (CNS), all of which appear to play major roles in fibromyalgia pathophysiology--and pain in fibromyalgia, and concludes by presenting a model of the pathophysiology of abnormal pain perception in fibromyalgia which integrates the research findings described.

Advances in the treatment of fibromyalgia: current status and future directions

Despite significant efforts devoted to understanding the etiopathogenesis of fibromyalgia, its treatment still presents a challenge to practicing clinicians, who must recognize the disorder and quantify the different symptoms in order to treat it. This article discusses recent research to identify sensitive and reliable measures for determining response to treatment among patients with FM, and the elements of therapeutic programs (pharmacologic and nonpharmacologic) for patients with FM along with the empirical or theoretical basis for their use. Future directions, including the need for systematic, controlled outcome studies of therapies and evaluation of variables which may mediate the effects of treatment, as well as demonstration that the effects produced in outcome studies generalize to settings beyond those in which the studies are initially conducted, are also discussed.

Abnormal functional activity of the central nervous system in fibromyalgia syndrome

The evaluation of pain is one of the major problems facing general practitioners and specialists in medicine. Although the source of pain can be usually be traced to specific abnormalities in a given organ system, some patients present with generalized pain syndromes, such as fibromyalgia, for which no specific source can be found. Some researchers have begun to consider that although there may be a somatic source of such pain at its initiation, over time the pain may be maintained or exacerbated by functional alterations in critical regions of the brain and spinal cord that are involved in pain processing or pain inhibition. This article describes the techniques currently used to measure regional cerebral blood flow (rCBF) in the brain by single photon emission computed tomography (SPECT) imaging, and reviews the SPECT and positron emission tomography literature concerning alterations in functional brain activity associated with pain in healthy individuals and in patients with chronic pain, including those with fibromyalgia. The article concludes by describing the implications of current knowledge about pain and abnormal functional brain activity in the understanding of the pathophysiology of fibromyalgia and in the development of therapeutic strategies to manage patients with this disorder.

Hereditary haemochromatosis mutation frequencies in the general population

OBJECTIVES

This study aims to expand our knowledge of the general population frequency of two mutations, C282Y and H63D, identified in the candidate gene for hereditary haemochromatosis, and to determine whether the testing can be performed using routinely obtained cheek-brush (buccal) samples.

SETTING

Banked buccal lysate samples, randomised and coded for anonymity, from a cohort of couples who underwent prenatal cystic fibrosis screening in Maine.

METHODS

A multiplex ARMS test was performed on buccal cell lysates to identify the two mutations.

RESULTS

Genotype frequencies found among the 1001 subjects studied (502 women, 499 men) were: seven C282Y homozygotes, 22 C282Y/H63D compound heterozygotes, 97 C282Y heterozygotes, 17 H63D homozygotes, 246 H63D heterozygotes, and 612 individuals with no detectable mutation. The allele frequencies for C282Y and H63D were 0.066 and 0.151, respectively.

CONCLUSIONS

Observed genotype frequencies in Maine are consistent with expectations and with consensus data from five smaller studies. Combined mutational analysis data indicate that homozygosity for C282Y (the genotype found in about 85% of subjects with diagnosed hereditary haemochromatosis) occurs in 51 per 10,000 white subjects of northern European heritage; the corresponding total hereditary haemochromatosis prevalence of about 60 per 10,000 is consistent with previous estimates. The study also confirms that H63D would not be useful in general population screening for hereditary haemochromatosis.

Sexual and physical abuse in women with fibromyalgia: association with outpatient health care utilization and pain medication usage

OBJECTIVE

To evaluate the relationship between sexual and/or physical abuse and health care usage in patients with fibromyalgia (FM) and identify variables that may influence this relationship.

METHODS

We assessed history of sexual/physical abuse, health care utilization, and medication usage, as well as related variables in 75 women with FM using standardized questionnaires, structured interviews, and laboratory pain perception tasks.

RESULTS

Fifty-seven percent of FM patients reported a history of sexual/physical abuse. Compared to non-abused patients, abused patients reported significantly greater utilization of outpatient health care services for problems other than FM and greater use of medications for pain (P < or = 0.025). Consistent with our expectations, abused patients also were characterized by significantly greater pain, fatigue, functional disability, and stress, as well as by a tendency to label dolorimeter stimuli as painful regardless of their intensities (P < or = 0.05). Additional analyses suggested that the high frequency of sexual/physical abuse in our patients was associated primarily with seeking health care for chronic pain rather than the FM syndrome itself or genetic factors.

CONCLUSION

There is an association in FM patients between sexual/physical abuse and increased use of outpatient health care services and medications for pain. This association may be influenced by clinical symptoms, functional disability, psychiatric disorders, stress, and abnormal pain perception. The relationships among these variables should be further tested in prospective, population-based studies.

Perceived physical and emotional trauma as precipitating events in fibromyalgia. Associations with health care seeking and disability status but not pain severity

OBJECTIVE

We examined relationships between perceived physical and emotional trauma that occur prior to, or that initiate, pain onset and health care seeking for fibromyalgia syndrome (FMS). We also assessed associations between perceived trauma and levels of health care usage, symptom severity, functional disability, and receipt of disability compensation among patients with FMS.

METHODS

We evaluated these variables using interviews and standardized instruments in a consecutive series of FMS patients and community residents who met the American College of Rheumatology criteria for FMS but had not sought medical care ("nonpatients").

RESULTS

Emotional trauma was associated with status as an FMS patient independently of demographics, physical trauma, and sexual/physical abuse (P = 0.007). Among patients, emotional trauma was related to a high number of physician visits (P = 0.013), functional disability ratings (P = 0.012), and fatigue (P = 0.029), but physical trauma was associated with receipt of disability compensation (P = 0.019). Trauma history was not related to pain severity or pain thresholds.

CONCLUSION

Perception of physical trauma is a greater determinant of disability compensation for FMS than is perceived emotional trauma, symptom severity, or functional disability. Effort should be devoted to understanding the social and legal factors underlying this observation, as well as to reducing high health care usage among FMS patients with emotional trauma.

Undetectable maternal serum unconjugated estriol levels in the second trimester: risk of perinatal complications associated with placental sulfatase deficiency

OBJECTIVE

Our purpose was to determine the prevalence of undetectably low second-trimester maternal serum unconjugated estriol levels and the association with increased perinatal morbidity or mortality in pregnancies at risk for placental sulfatase deficiency.

STUDY DESIGN

Nine centers in New England identified singleton pregnancies with undetectably low unconjugated estriol levels. Each unexplained case was matched with four controls; pregnancy outcome information was sought.

RESULTS

Among 130,295 pregnancies surveyed, undetectably low unconjugated estriol levels were identified in 167 (13/10,000). Explanations included fetal death (53), overestimated gestational age (50), nonpregnancy (12), and chromosome abnormalities (5). The 41 unexplained cases were compared with 163 matched controls. Male offspring were more frequent (85%) among cases than among controls (55%). Although rates of perinatal complications were not significantly different, primary cesarean sections occurred about twice as often among cases. No perinatal deaths occurred.

CONCLUSIONS

Neither severity of symptoms nor perinatal morbidity or mortality currently warrant routine interpretation of unexplained undetectably low unconjugated estriol levels as a marker for placental sulfatase deficiency.

Prenatal screening for cystic fibrosis: an updated perspective

In U.S. white populations prenatal screening for cystic fibrosis can identify > or = 60% of pregnancies in which the risk for an affected fetus is high. Such pregnancies occur when both the mother and the father carry cystic fibrosis mutations; about one screened couple per 1000 falls into this category. The risk of the fetus being affected is 1 in 4. Prenatal screening for cystic fibrosis compares favorably with prenatal screening for spina bifida and Down syndrome, with a similar detection rate, a much lower false-positive rate, and greater odds of being affected, given a positive result. Intervention trials in Europe and the United States provide documentation of efficacy. Larger-scale trials should now be encouraged in the United States to gain further insight into program design and case management, as a way to determine the feasibility of cystic fibrosis screening as part of routine prenatal care.

Triple marker screening in native Japanese women

Prenatal screening using the maternal serum markers alpha-fetoprotein, human chorionic gonadotropin, and unconjugated oestriol was investigated in a native Japanese population. Comparison with a Caucasian U.S. population revealed differences which led to modification of the generally used equations for risk calculations. Prenatal screening was shown to be clinically useful.

Asthma and gastroesophageal reflux: acid suppressive therapy improves asthma outcome

PURPOSE

To determine (1) the appropriate omeprazole (Prilosec) dose required for adequate acid suppression in asthmatics with gastroesophageal reflux, (2) whether aggressive acid suppressive therapy of gastroesophageal reflux improves asthma outcome in asthmatics with gastroesophageal reflux, (3) the time course of asthma improvement, and (4) demographic, esophageal, or pulmonary predictors of a positive asthma response to antireflux therapy.

PATIENTS AND METHODS

Thirty nonsmoking adult asthmatics with gastroesophageal reflux (asthma defined by American Thoracic Society criteria and reflux defined by symptoms and abnormal 24-hour esophageal pH testing) were recruited from the outpatient clinics of a 900-bed university hospital. Patients underwent baseline studies including a demographic questionnaire, esophageal manometry, dual-probe 24-hour esophageal pH test, barium esophogram, and pulmonary spirometry. During the 4-week pretherapy phase, patients recorded reflux and asthma symptom scores and peak expiratory flow rates (PEFs) upon awakening, 1 hour after dinner, and at bedtime. Patients began 20 mg/d omeprazole, and the dose was titrated until acid suppression was documented by 24-hour pH test. Patients remained on this acid suppressive dose for 3 months. Responders were identified by a priori definitions: asthma symptom reduction by >20% and/or PEF increase by >20%. Asthma symptom scores, PEF's baseline and posttherapy pulmonary spirometry were analyzed.

RESULTS

Twenty-two (73%) patients were asthma symptom and /or PEF responders: 20 (67%) were asthma symptom responders, and 6 (20%) were PEF responders. Responders reduced their asthma symptoms by 57% (P<0.001), improved their morning and night PEFs by 8% and 9% (both P <0.005), and had improvement in forced expiratory volume at 1 second (P <0.02), mean forced expiratory flow during the middle half (25% to 75%) of the forced vital capacity (P <0.04), and peak expiratory flow (P <0.01) with acid suppressive therapy. Mean acid suppressive dose of omeprazole was 27 mg/d (+/-2.2) with 27% (8) patients requiring more than 20 mg/d. The presence of regurgitation or excessive proximal esophageal reflux predicted asthma response with 100% sensitivity, 100% negative predictive value, specificity of 44% and a positive predictive value of 79%.

CONCLUSIONS

Acid suppressive therapy with omeprazole improves asthma symptoms and/or PEFs by >20% and improves pulmonary function in 73% of asthmatics with gastroesophageal reflux after 3 months of acid suppressive therapy. Many asthmatics (27%) required >20 mg/d of omeprazole to suppress acid. The presence of regurgitation and/or excessive proximal esophageal reflux predicts a positive asthma outcome.

Drug treatment of functional dyspepsia: a systematic analysis of trial methodology with recommendations for design of future trials

OBJECTIVES

To evaluate drug treatment of functional dyspepsia (including Helicobacter pylori) and provide guidelines for future trials based on a critical systematic overview of published studies.

METHODS

Data sources were a Medline search for articles published in English going back to 1966 and a manual search of four GI journals going back to 1980. Original randomized, double-blind, placebo-controlled trials were selected that enrolled at least 20 patients. Using a standardized, pretested data extraction form, studies were evaluated independently by two observers for study design, outcome measures, and results.

RESULTS

Fifty two eligible studies were evaluated. Many studies suffered from important weaknesses in study design and execution. Only five studies used previously validated outcome measures.

CONCLUSIONS

Because of suboptimal design and/or unclear presentation of the data, none of the trials provided unequivocal evidence that there is efficacious therapy for the treatment of functional dyspepsia.

Psychiatric diagnoses in patients with fibromyalgia are related to health care-seeking behavior rather than to illness

OBJECTIVE

To compare the frequency of lifetime psychiatric disorders among 3 groups of subjects: patients with fibromyalgia syndrome (FMS) from a tertiary care setting, community residents with FMS who had not sought medical care for their FMS symptoms ("FMS nonpatients"), and healthy controls.

METHODS

We used the Computerized Diagnostic Interview Schedule to assess lifetime psychiatric diagnoses, as well as the Center for Epidemiological Studies Depression scale and the Trait Anxiety Inventory to assess current psychological distress, among 64 patients with FMS, 28 FMS nonpatients, and 23 healthy individuals.

RESULTS

Patients with FMS, relative to FMS nonpatients and healthy controls, were characterized by a significantly greater number of lifetime psychiatric diagnoses (P = 0.002). Nonpatients did not differ from controls in psychiatric diagnoses. Patients also exhibited higher psychological distress levels than nonpatients, and nonpatients showed greater distress than controls. Differences in psychological distress between patients and nonpatients were eliminated after controlling for pain threshold and fatigue ratings.

CONCLUSION

Psychiatric disorders are not intrinsically related to the FMS syndrome. Instead, multiple lifetime psychiatric diagnoses may contribute to the decision to seek medical care for FMS in tertiary care settings.

Population screening for haemochromatosis: a unifying analysis of published intervention trials

OBJECTIVES

To examine the efficacy of population screening for haemochromatosis by analysing the screening performance of seven intervention trials, and to compare this with the expected performance derived from family studies.

SETTING

Seven population intervention trials carried out between 1983 and 1995 in Australia, Scandinavia, Iceland, and the United State.

METHODS

Seven of 23 English language trials identified were suitable for the meta-analysis. Transferrin saturation and serum ferritin measurements derived from family studies were used to predict detection and false positive rates for each trial.

RESULTS

The seven trials used various screening and diagnostic criteria. A total of 18,396 men and 12,254 women were screened. Because some cases were not detected by screening, and some screen positive individuals did not complete diagnostic testing, the prevalence of homozygous individuals was underestimated in all the trials. The reported and predicted percentages of screen positive individuals nearly always agreed. The homozygote prevalence was estimated to be 34 men and 40 women per 10,000 (prevalence predicted from family studies is 53 per 10,000). Clinical manifestations were present in 50% of male and 44% of female homozygotes.

CONCLUSIONS

False positive rates, homozygote prevalences, and frequency of clinical manifestations were in general agreement with predictions from family studies. However, incomplete understanding about a number of issues requires that further pilot trials be carried out before screening can be considered part of routine medical practice.

Population screening for haemochromatosis: expectations based on a study of relatives of symptomatic probands

OBJECTIVES

The frequency of symptomatic haemochromatosis in the general population and the potential efficacy of population screening is uncertain. Data from family members of clinically diagnosed index cases were used to estimate the frequency of the haemochromatosis genotype, the proportion of homozygous individuals with clinical manifestations, and the efficacy of transferrin saturation and serum ferritin measurements as screening tests.

SETTING

English language studies from Europe, North America, and Australia.

METHODS

Haemochromatosis zygosity was classified only by HLA haplotyping, the most reliable available method. All subsequent analyses were based on family members classified in this way.

RESULTS

An estimated 53 individuals per 10,000 are homozygous for haemochromatosis. Overall, 67% of male and 41% of female family members display at least one clinical manifestation; for men, the frequency increases with age. Transferrin saturation levels are 70% or above in an estimated 72% of homozygous men, along with three per 1000 heterozygous or unaffected men. Transferrin saturation levels are 60% or above in an estimated 67% of homozygous women, along with six per 1000 heterozygous or unaffected women. Serum ferritin levels, but not transferrin saturation levels, are associated with clinical manifestations.

CONCLUSIONS

This information can be used to compare expected versus actual screening performance for intervention trials aimed at detecting haemochromatosis in the general population.

Gastroesophageal reflux-induced bronchoconstriction. Is microaspiration a factor?

STUDY OBJECTIVE

To evaluate the role of microaspiration in gastroesophageal reflux-induced bronchoconstriction.

DESIGN

Prospective study blinded to the subject.

SETTING

Outpatient laboratory of a 908-bed university hospital.

PARTICIPANTS

Thirty nonsmoking adults divided into two groups: asthmatics with reflux (AR), 20; and subjects with gastroesophageal reflux (R), 10.

INTERVENTIONS

Dual esophageal pH probe placed. Esophageal infusions of normal saline solution, 0.1N hydrochloric acid, then normal saline solution, each lasting 18 min, were followed by two 20-min recovery periods. Subjects remained in the supine position throughout. Spirometry and specific airway resistance (SRaw) performed at baseline, after each esophageal infusion and recovery period. Proximal esophageal acid exposure, a requirement for microaspiration, was assessed by the proximal esophageal pH probe.

RESULTS

Peak expiratory flow rate (PEF) decreased with esophageal acid in the AR group and did not recover immediately despite esophageal acid clearance with a significant main effect of subject groups (p < 0.021) by repeated measures analysis of covariance. This decrease in PEF was not associated with the presence of proximal esophageal acid exposure (p = 0.618). Specific airway resistance increased in the AR group with esophageal acid and worsened despite acid clearance, especially during the second recovery phase, with a significant phase (p < 0.009) and group by treatment effect (p < 0.009). The presence of proximal esophageal acid exposure was not associated with this deterioration in SRaw (p = 1.0).

CONCLUSIONS

Esophageal acid infusions given in the supine position caused a decrease in PEF and an increase in SRaw in the asthma with reflux group, which did not improve despite acid clearance. These responses were not dependent on proximal esophageal acid exposure. Also, SRaw continued to worsen during the recovery phase in the AR group, which may represent a delayed bronchoconstrictor effect. These data suggest that microaspiration does not play a significant role in esophageal acid-induced bronchoconstriction.

Pregnancy outcome for women with very low levels of maternal serum unconjugated estriol on second-trimester screening

OBJECTIVE

Our purpose was to assess pregnancy outcome for women whose second-trimester triple screen results revealed very low unconjugated estriol levels.

STUDY DESIGN

Of 44,146 women screened for alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol, a group of women with isolated very low unconjugated estriol levels were selected as the study group. Pregnancy outcome was obtained by contacting the referring physicians.

RESULTS

During the study period 62 women had unconjugated estriol levels at or below the sensitivity of the assay. Fetal death was the most common explanation, accounting for 37.1% of cases. Six cases of early death followed uneventful prenatal visits. Eighteen women had unexplained very low unconjugated estriol levels. Of these 18, four cases of placental sulfatase deficiency were diagnosed. Sixteen of these 18 women gave birth to male infants (p = 0.03).

CONCLUSION

A very low unconjugated estriol level in the second trimester is associated with increased risk for early death and placental sulfatase deficiency.

Decreases in health care resource utilization in patients with rheumatoid arthritis following a cognitive behavioral intervention

We previously reported the efficacy of a multicomponent cognitive-behavioral intervention including biofeedback to decrease pain, affective distress, and objective measures of disease activity in patients with rheumatoid arthritis (RA). In the present article we report evidence that this intervention is associated with reductions in RA-related clinic visits and days hospitalized as well as reductions in the costs of these medical services. Data were independently and objectively collected over an 18-month interval as part of a controlled group outcome study. The importance of documenting economic as well as clinical benefits of our treatments in specific patient populations is noted.

Development of an observation method for assessing pain behaviors in children with juvenile rheumatoid arthritis

OBJECTIVE

To develop an observation method for assessing pain behaviors in children with juvenile rheumatoid arthritis (JRA).

METHODS

Thirty children with JRA performed a standardized sequence of activities for video recording, and correlations between the pain behaviors observed on the videotapes and established measures of pain, depression, and functional disability were determined.

RESULTS

Pain behaviors were reliably observed (kappa coefficients 0.53-0.79). Total pain behaviors were significantly correlated with subjective reports of pain (r = 0.50) and disability levels (r = 0.64). These behaviors were not significantly associated with children's depression ratings (r = 23).

CONCLUSION

The results indicate that the behavioral observation method provides a reliable and valid measure of pain associated with JRA. Measurement of pain behaviors may be especially useful in treatment outcome studies because these behaviors are relatively independent of depression.

Fibromyalgia in women. Abnormalities of regional cerebral blood flow in the thalamus and the caudate nucleus are associated with low pain threshold levels

OBJECTIVE

To determine if regional cerebral blood flow (rCBF) in the left and right hemithalami or the left and right heads of the caudate nucleus is abnormal in women with fibromyalgia (FM).

METHODS

Resting-state rCBF in the hemithalami and left and right heads of the caudate nucleus of 10 untreated women with FM and 7 normal control women was measured by single-photon-emission computed tomography. Pain threshold levels at tender and control points also were assessed in both the women with FM and the controls.

RESULTS

The rCBF in the left and right hemithalami and the left and right heads of the caudate nucleus was significantly lower in women with FM than in normal controls (P = 0.01, P = 0.003, P = 0.01, and P = 0.02, respectively). Compared with controls, the women with FM also were characterized by significantly lower cortical rCBF (P = 0.001) and lower pain threshold levels at both tender points (P = 0.0001) and control points (P = 0.0001).

CONCLUSION

The findings of low rCBF and generalized low pain thresholds support the hypothesis that abnormal pain perception in women with FM may result from a functional abnormality within the central nervous system.