The differentiating effect of COVID-19-associated stress on the morbidity of blood donors with symptoms of hidradenitis suppurativa, hyperhidrosis, or psoriasis

PURPOSE

The burden of different skin diseases may vary leading individuals to have different sensitivity to stress. Therefore, we compared the health-related quality of life (HRQoL) and stress before and during the universal stress from the severe acute respiratory syndrome coronavirus-2-pandemic in individuals with and without hyperhidrosis, hidradenitis suppurativa, or psoriasis.

METHODS

The study cohort was the Danish Blood Donor Study. Overall, 12,798 participants completed a baseline questionnaire before the pandemic, in 2018-2019, and a follow-up questionnaire during the pandemic, in 2020. Regression determined the association between the skin diseases and outcomes. Outcomes were the physical and mental component summary (MCS, PCS, respectively), which assess the mental and physical HRQoL, and the perceived stress scale, which assesses stress in the past four weeks.

RESULTS

Overall, 1168 (9.1%) participants had hyperhidrosis, 363 (2.8%) had hidradenitis suppurativa, and 402 (3.1%) had psoriasis. At follow-up, the participants with hyperhidrosis had worse MCS (coefficient -0.59 [95% confidence interval (CI) -1.05, -0.13]) and higher odds of moderate-to-severe stress (odds ratio 1.37 [95% CI 1.13, 1.65]) and the participants with hidradenitis suppurativa worse PCS (coefficient -0.74 [95% CI -1.21, -0.27]) than the control groups. The associations were independent of baseline HRQoL, stress, the Connor-Davidson Resilience scale, and other covariables. Psoriasis was not associated with the outcomes.

CONCLUSION

Individuals with hyperhidrosis or hidradenitis suppurativa experienced worse mental or physical well-being and individuals with hyperhidrosis also had higher stress during the pandemic compared to healthy individuals. This suggests that individuals with these skin diseases are particularly susceptible to external stress.

Human leukocyte antigen system associations in Malassezia-related skin diseases

BACKGROUND

The human leukocyte antigen system (HLA) is divided into two classes involved in antigen presentation: class I presenting intracellular antigens and class II presenting extracellular antigens. While susceptibility to infections is correlated with the HLA system, data on associations between HLA genotypes and Malassezia-related skin diseases (MRSD) are lacking. Thus, the objective of this study was to investigate associations between HLA alleles and MRSD.

MATERIALS AND METHODS

Participants in The Danish Blood Donor Study (2010-2018) provided questionnaire data on life style, anthropometric measures, and registry data on filled prescriptions. Genotyping was done using Illumina Infinium Global Screening Array, and HLA alleles were imputed using the HIBAG algorithm. Cases and controls were defined using filled prescriptions on topical ketoconazole 2% as a proxy of MRSD. Logistic regressions assessed associations between HLA alleles and MRSD adjusted for confounders and Bonferroni corrected for multiple tests.

RESULTS

A total of 9455 participants were considered MRSD cases and 24,144 participants as controls. We identified four risk alleles B*57:01, OR 1.19 (95% CI: 1.09-1.31), C*01:02, OR 1.19 (95% CI: 1.08-1.32), C*06:02, OR 1.14 (95% CI: 1.08-1.22), and DRB1*01:01, OR 1.10 (95% CI: 1.04-1.17), and two protective alleles, DQB1*02:01, OR 0.89 (95% CI: 0.85-0.94), and DRB1*03:01, OR 0.89 (95% CI: 0.85-0.94).

CONCLUSION

Five novel associations between HLA alleles and MRSD were identified in our cohort, and one previous association was confirmed. Future studies should assess the correlation between Malassezia antigens and antigen-binding properties of the associated HLA alleles.

POS0261 TIME SINCE LAST RITUXIMAB TREATMENT IS ESSENTIAL FOR DEVELOPING A HUMORAL RESPONSE TO THE COVID-19 MRNA VACCINE IN PATIENTS WITH RHEUMATIC DISEASES

Background

Concerns about Rituximab (RTX) treatment and potentially inadequate vaccine response were aired early in the pandemic, and initial data seem to support this concern (1). So far, studies regarding rheumatic patients and the COVID-19 vaccines have included a relatively small number of patients receiving rituximab.

Objectives

We aimed to investigate if patients with rheumatic diseases treated with RTX raise a serological response towards the COVID-19 mRNA vaccines and to elucidate the influence of time since the last dose RTX before vaccination on this response.

Methods

We included 201 patients followed at the Department of Rheumatology, Aarhus University Hospital. All had been treated with RTX in the period 2017-2021, and had finished a two-dose COVID-19 mRNA vaccination. All patients and 44 blood donors had total antibodies against SARS-CoV2 spike protein measured. Univariate and multivariate logistic regression were used.

Results

Patients were predominantly female (67%) with a median age of 62 years. The most frequent diagnosis was ANCA-associated vasculitis (32%), rheumatoid arthritis (31%), and myositis (14%), and 97% had the Pfizer/Biontic vaccine. Median number of RTX infusions were 5 (IQR 2-8), with a cumulative dose of 4g (2-8), and 72% had received RTX within the last 15 months. Prednisone was used by 43%, followed by methotrexate (25%), hydroxychloroquine (11%) and azathioprine (10%).

We observed a time-dependent increase in antibody response as the interval from the last RTX treatment to vaccination increased (Table 1). Only 17.3% of patients developed a detectable antibody response after receiving their vaccination 6 months or less after their previous RTX treatment (Figure 1). Positive antibody response increased to 66.7% in patients who had RTX 9-12 months before vaccination. Neither cumulative treatment time nor cumulative RTX dose seemed to influence the serological response to the vaccine (Table 1). Thus, even in patients who have received RTX for a substantial time, expanding time-since-last-RTX treatment could prove beneficial for increasing the chance of a serological response. We further found that “months between last Rtx and vaccination”, prednisone and azathioprine treatment were alle negatively associated with antibody response in a multivariate logistic regression analysis(Table 1). All blood donors (100%) had detectable antibodies after vaccination.

Table 1.

Logistic regression analysis with precense of SARS-CoV-2 antibodies after mRNA vaccination as dependent varaible.

UnivariateOR95% CIP-valueSex, female = ref.0.910.50 - 1.670.77Age, years0.980.96 - 1.000.09Diagnosis1.050.99 – 1.130.08Months between last RTX and vaccination1.061.03 - 1.09<0.001Total number of RTX infusions0.960.92 - 1.010.10Total dose of RTX, mg0.970.92 - 1.020.18Time from first to last RTX treatment1.001.00 - 1.000.57No DMARD treatment0.940.50 - 1.780.85Prednisone, dose in mg0.910.85 - 0.990.02Methotrexate1.710.90 - 3.250.10Hydroxychloroquine0.870.35 - 2.190.77Azathioprine0.230.06 - 0.800.02Multivariate modelMonths between last Rtx and vaccination1.081.04 - 1.11<0.001Prednisone treatment, mg0.910.84 - 0.990.03Azathioprine treatment0.100.02 - 0.440.002

All significant variables in the univariate analysis were included in the multivariate model.

Conclusion

In conclusion, patients with rheumatic diseases treated with RTX have a severely impaired serological response towards the COVID-19 mRNA vaccine. This is especially true if the interval between RTX treatment and vaccination is less than 9 months. For the majority of RTX treated patients, the recommended six months since last RTX is insufficient to develop a humoral response to COVID-19 mRNA vaccines. Our data suggest that the current recommendations of a 6 months interval should be revised.

References

[1]Ammitzbøll C, et al. Impaired antibody response to the BNT162b2 mRNA COVID-19 vaccine in patients with Systemic Lupus Erythematosus and Rheumatoid Arthritis. ACR Open Rheumatol. 2021;

Disclosure of Interests

None declared

POS1198 VACCINATION AGAINST COVID-19 SHOULD BE ENCOURAGED IN PATIENTS WITH RHEUMATIC DISEASE, AS MOST PATIENTS DEVELOP A SEROLOGICAL RESPONSE AGAINST THE VACCINE AND VACCINATION REDUCES SELF-IMPOSED ISOLATION AND SHIELDING BEHAVIOR

Background

Vaccine trials of the SARS-CoV-2 mRNA vaccines were encouraging but excluded most patients with rheumatic diseases (RD) and patients treated with immunosuppressive therapy. However, reports of a more severe COVID-19 disease course in patients with RDs prompted strategies for expediting vaccination of RD patients in most countries.

In addition to the impact experienced by most people of the pandemic, patients with RDs were adversely impacted by the potential risk of severe COVID-19 due to their disease and immunosuppressive treatment. Fear of COVID-19 led to disproportionate anxiety, self-isolation, and shielding behavior for many RD patients at the beginning of the pandemic.

Objectives

We investigated antibody levels in serum against SARS-CoV-2 after a two-dose vaccination with an mRNA vaccine in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Further, we examined the association between reactogenicity and immunogenicity and how vaccination influenced patient behavior concerning fear of COVID-19 and shielding.

Methods

Patients with SLE or RA from the COPANARD (Corona PANdemic Autoimmune Rheumatic Disease)1 cohort received two doses of an mRNA vaccine between January and August 2021 and had total antibodies against SARS-CoV-2 measured before vaccination and 2 and 9 weeks after the second vaccination. In addition, patients answered an electronic questionnaire before and eight weeks after vaccination concerning behavior, anxiety, and symptoms of depression (PHQ-9).

Results

Three-hundred-and-three patients and 44 blood donors (healthy controls) were included. Significantly fewer patients (90%) had measurable antibodies against SARS-CoV-2 compared to blood donors (100%) after the second vaccination (p<0.001) (Figure 1). Treatment with Rituximab was the strongest predictor of unfavorable vaccine response, as only 27% were seropositive after vaccination. We found a negative effect of prednisone and methotrexate but no effect of age, comorbidity, or pausing medication on seroconversion. Patients experienced significant improvement after vaccination in 10 out of 12 questions regarding behavior and fear of COVID-19, but no change was observed in symptoms of depression (p=0.62) or anxiety (p=0.46).

Figure 1.

Total antibody response against SARS-CoV-2 after two mRNA vaccines. Antibody response against mRNA COVID-19 vaccine pre-vaccination, 1 and 9 weeks after in patients with rheumatic diseases and 5-6 weeks after vaccination in blood donors. (A) Percentage with measurable SARS-CoV-2 antibody results after vaccination. (B) Levels of SARS-CoV-2 antibodies in serum.

Conclusion

The majority of patients with SLE or RA had a measurable serological response to the COVID-19 mRNA vaccine after two doses. Treatment with Rituximab was the strongest predictor of no seroconversion.

Our findings warrant encouragement of vaccination against COVID-19 for patients with RD, as most patients benefits with both a serological immune response and reduced isolation and shielding behavior.

References

[1]Ammitzbøll C, Andersen JB, Vils SR, Mistegaard CE, Mikkelsen S, Erikstrup C, Thomsen MK, Hauge EM, Troldborg A. Arthritis Care Res (Hoboken). 2021 May 31:10.1002/acr.24716. doi: 10.1002/acr.24716. Online ahead of print.

Disclosure of Interests

None declared

Patients’ perspectives on point-of-care diagnostics and treatment by emergency medical technicians in acute COPD exacerbations: A qualitative study

Background

In Denmark emergency medical technicians transport patients with acute COPD exacerbations to the nearest emergency department. From a clinical and economic perspective, this transport and assessment at the hospital may be inconvenient if the patient is immediately discharged from the emergency department. We established an emergency technical technicians point-of-care diagnostics and treatment program of patients with COPD with use of ultrasound and blood analysis. Patients' perspectives on treatment at home and sense of security are important to qualify clinical practice at home with patients with acute exacerbation.

Aim and objectives

To explore patient's and relatives' experience of treatment at home during emergency calls due to COPD in exacerbation and to investigate their attitude to avoid hospitalization as well as experience of stress during point-of-care diagnostics in their own home.

Method

A qualitative study comprising semi-structured interviews with 16 patients carried out from April 1st, 2019 to March 31st, 2020 in Denmark. Data was analysed inspired by Malteruds’ text condensation and informed by Critical Psychology with first person perspective focusing on the patient's views on point-of-care diagnostics and treatment of their COPD in acute exacerbation.

Results

The interviews revealed that in order to ensure an experience of quality in the assessment and treatment of patients in their own homes, it was important that the ambulance staff showed great safety and experience in the use of the technical equipment and treatment of dyspnea. It was also of importance that the patients felt confident that their general practitioner followed up on the home treatment initiated.

Conclusion

Patients’ perspectives showed that point-of-care diagnostics and treatment of acute COPD in exacerbation was considered a qualitative offer by the patients and their relatives. At the same time, it was crucial that the emergency medical technicians showed experience and safety in handling shortness of breath as well as the technical equipment.

Trial registration: Approved by the Danish Data Protection Agency Project-ID: 20/24845.

POS1171 THE COVID-19 PANDEMIC PROMPTS ISOLATION AND BEHAVIORAL CHANGES IN PATIENTS WITH CHRONIC RHEUMATIC DISEASES LEADING TO REDUCED PHYSICAL ACTIVITY, INCREASED PAIN, DISEASE ACTIVITY, AND LOW SEROPREVALENCE OF SARS-CoV2 ANTIBODIES

Background:

The coronavirus disease 2019 (COVID-19) pandemic has complicated the management of chronic rheumatic diseases (CRD). Patients with CRDs are immunocompromised and generally prone to infection. The fear of COVID-19 and the degree of the self-imposed shielding strategy implemented by many patients introduced new challenges for the patients. Although recommendations have been developed to manage patients with CRDs by, i.e., EULAR, strong evidence is still lacking to guide treatment decisions.

Objectives:

This study aimed to assess the seroprevalence of SARS-CoV-2 antibodies in patients with CRDs and healthy controls during the first wave of the pandemic. We further evaluated the effect of the pandemic on patient behavior regarding medication, exercise, pain, and experienced disease activity. Finally, we investigated the self-perceived consequences of the pandemic and lock-down on anxiety and depression in patients with CRDs compared with healthy controls.

Methods:

More than 900 participants were included in the study: 405 patients with rheumatoid arthritis or systemic lupus erythematosus and 513 blood donors. All participants had SARS-CoV-2 antibodies measured (Wantai SARS-CoV-2 total antibody ELISA; sensitivity 96.7%, specificity 99.5%) and answered a questionnaire concerning behavior, anxiety, and symptoms of depression (PHQ-9). The participants with CRD were further asked about physical activity, adherence to medication, and disease-related symptoms.

Results:

CRD patients had a sixfold lower seroprevalence of SARS-CoV-2 antibodies compared to controls (p=0.03) (Figure 1). Almost 60% of patients were unable to exercise as usual, leading to increased pain in 34%, and experience of increased disease activity in 27%. Approximately 10% of patients reduced or discontinued their immunosuppressive treatments at their own initiative. Symptoms of moderate depression were present in 19% of patients compared to 6,8% of controls (p<0.001).

Figure 1.

Presence of SARS-CoV-19 antibodies in chronic rheumatic disease patients (1/365, 0.3%) and controls (blood donors (10/513, 1.9%), *(p=0.03).

Conclusion:

Low seroprevalence in patients with CRDs indicates successful mitigation of exposure to SARS-CoV-2. However, this appears to occur at the expense of physical activity and adherence to immunosuppressive treatment. Our results raise an important concern regarding the consequences of isolation for patients with CRDs. The result of physical isolation is a risk of severe mental health issues, physical inactivity, self-medication, increased pain, and increased disease activity. The long-term consequences of recommendations for patients with CRDs should be taken into account when tackling the continuing pandemic.

Table 1.Patient characteristicsCRD cohortBlood donorsPatients included, n405 (206 SLE, 199 RA)513Disease duration, years (IQR)12.9(7.0-23.0)Age, years (IQR)56.9(43.6-66.9)47(33-57)BMI, kg/m2 (IQR)25.0(22.1-28.6)25.5(23.1-28.4)Charlson Comorbidity Index, score (IQR)2(1-4)Behavioral and mental changes due to the risk of COVID-19CRD cohortBlood donorsp-valueWashes hands more often (%)91.691.40.92Coughing or sneezing in the elbow (%)83.084.00.67Wearing face mask (%)5.02.40.001Restricts the use of public transport (%)47.432.9<0.001Avoid places where many people are gathered (%)80.770.0<0.001Stay at home (%)51.635.3<0.001Symptoms of moderate depression, PHQ-9 >=10, (%)19.016.75<0.001Pandemic effect on training, pain and disease activityCRD cohortHave you been able to exercise as usually, yes (%)41.4Have you been less physically active due to COVID-19, yes (%)44.7Has the degree of physical activity increased the pain from your rheumatological disease? yes(%)33.9Have you experienced increased disease activity during COVID-19? yes(%)26.9

Interquartile range (IQR), Patient Health Questionnaire-9 (PHQ-9),

Acknowledgements:

This study was funded by the Danish Rheumatism Association. We are thankful for the help with creation of the questionnaire by patient research partners Lene Mandrup Thomsen, Nanna Bacci Hartz, Lene Lau og Jeanette Andersen.

Disclosure of Interests:

Christian Ammitzbøll: None declared, Jakob Bøgh Andersen: None declared, Signe Risbøl Vils: None declared, Clara Mistegaard Jørgensen: None declared, Ellen-Margrethe Hauge Speakers bureau: AbbVie, Sanofi, Sobi, MSD, UCB, Grant/research support from: Roche, Norvartis, Christian Erikstrup: None declared, Susan Mikkelsen: None declared, Marianne Kragh Thomsen: None declared, Anne Troldborg: None declared.

The continuous reaction time test for minimal hepatic encephalopathy validated by a randomized controlled multi-modal intervention-A pilot study

Background

Minimal hepatic encephalopathy (MHE) is clinically undetectable and the diagnosis requires psychometric tests. However, a lack of clarity exists as to whether the tests are in fact able to detect changes in cognition.

Aim

To examine if the continuous reaction time test (CRT) can detect changes in cognition with anti-HE intervention in patients with cirrhosis and without clinically manifest hepatic encephalopathy (HE).

Methods

Firstly, we conducted a reproducibility analysis and secondly measured change in CRT induced by anti-HE treatment in a randomized controlled pilot study: We stratified 44 patients with liver cirrhosis and without clinically manifest HE according to a normal (n = 22) or abnormal (n = 22) CRT. Each stratum was then block randomized to receive multimodal anti-HE intervention (lactulose+branched-chain amino acids+rifaximin) or triple placebos for 3 months in a double-blinded fashion. The CRT is a simple PC-based test and the test result, the CRT index (normal threshold > 1.9), describes the patient’s stability of alertness during the 10–minute test. Our study outcome was the change in CRT index in each group at study exit. The portosystemic encephalopathy (PSE) test, a paper-and-pencil test battery (normal threshold above -5), was used as a comparator test according to international guidelines.

Results

The patients with an abnormal CRT index who were randomized to receive the active intervention normalized or improved their CRT index (mean change 0.92 ± 0.29, p = 0.01). Additionally, their PSE improved (change 3.85 ± 1.83, p = 0.03). There was no such effect in any of the other study groups.

Conclusion

In this cohort of patients with liver cirrhosis and no manifest HE, the CRT identified a group in whom cognition improved with intensive anti-HE intervention. This finding infers that the CRT can detect a response to treatment and might help in selecting patients for treatment.

Termination of pre-hospital resuscitation by anaesthesiologists - causes and consequences. A retrospective study

AIM

Differentiating between a newly deceased patient and the lifeless patient in whom immediate resuscitation is required may be facilitated by a pre-hospital anaesthesiologist. The purpose of our study was to investigate to what extent and why the pre-hospital anaesthesiologist pronounced life extinct in situations where an emergency medical technician (EMT) would have been required to resuscitate.

METHODS

All lifeless patients seen pre-hospitally by the anaesthesiologist-manned Mobile Emergency Care Unit in Odense, Denmark, from 2010 to 2014 were retrospectively studied.

RESULTS

Of 17 035 contacts, 1275 patients were lifeless without reliable signs of death. In 642 of these patients (3.8%) resuscitation was initiated (median age 68 years). The remaining 633 patients (3.7%) were declared dead at the scene without any resuscitation attempt (median age 77 years). These latter patients would have been attempted resuscitated, had the anaesthesiologist not been present. In 54.5% of cases where documentation was available in the patient records, reasons for not resuscitating these patients included time elapsed from incident to contact with physician, 'overall assessment', chronic disease, or do-not-resuscitate order.

CONCLUSION

In one patient in 30, the MECU refrained from futile resuscitation in cases where legislation required an EMT to initiate resuscitation. This practice reduced unethical attempts of resuscitation, reduced unnecessary emergency ambulance transports, and reduced the work load of the hospital resuscitation teams for one unnecessary alarm every third day. Differentiating between lifeless patients and dead patients not exhibiting reliable signs of death, however, is a complex task which is only sparsely documented.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Digital questionnaire platform in the Danish Blood Donor Study

OBJECTIVES

The Danish Blood Donor Study (DBDS) is a prospective, population-based study and biobank. Since 2010, 100,000 Danish blood donors have been included in the study. Prior to July 2015 all participating donors had to complete a paper-based questionnaire. Here we describe the establishment of a digital tablet-based questionnaire platform implemented in blood bank sites across Denmark.

METHODS

The digital questionnaire was developed using the open source survey software tool LimeSurvey. The participants accesses the questionnaire online with a standard SSL encrypted HTTP connection using their personal civil registration numbers. The questionnaire is placed at a front-end web server and a collection server retrieves the completed questionnaires. Data from blood samples, register data, genetic data and verification of signed informed consent are then transferred to and merged with the questionnaire data in the DBDS database.

RESULTS

The digital platform enables personalized questionnaires, presenting only questions relevant to the specific donor by hiding unneeded follow-up questions on screening question results. New versions of questionnaires are immediately available at all blood collection facilities when new projects are initiated.

CONCLUSION

The digital platform is a faster, cost-effective and more flexible solution to collect valid data from participating donors compared to paper-based questionnaires. The overall system can be used around the world by the use of Internet connection, but the level of security depends on the sensitivity of the data to be collected.

Effect of early supervised progressive resistance training compared to unsupervised home-based exercise after fast-track total hip replacement applied to patients with preoperative functional limitations. A single-blinded randomised controlled trial

OBJECTIVE

To examine if 2 weekly sessions of supervised progressive resistance training (PRT) in combination with 5 weekly sessions of unsupervised home-based exercise is more effective than 7 weekly sessions of unsupervised home-based exercise in improving leg-extension power of the operated leg 10 weeks after total hip replacement (THR) in patients with lower pre-operative function.

METHOD

A total of 73 patients scheduled for THR were randomised (1:1) to intervention group (IG, home based exercise 5 days/week and PRT 2 days/week) or control group (CG, home based exercise 7 days/week). The primary endpoint was change in leg extension power at 10 week follow up. Secondary outcomes were isometric hip muscle strength, sit-to-stand test, stair climb test, 20 m walking speed and patient-reported outcome (HOOS).

RESULTS

Sixty-two completed the trial (85%). Leg extension power increased from baseline to the 10 week follow up in both groups; mean [95% CI] IG: 0.29 [0.13; 0.45] and CG: 0.26 [0.10; 0.42] W/kg, with no between-group difference (primary outcome) (P = 0.79). Maximal walking speed (P = 0.008) and stair climb performance (P = 0.04) improved more in the IG compared to CG, no other between-group differences existed.

CONCLUSIONS

In this trial, supervised PRT twice a week in addition to 5 weekly sessions of unsupervised exercise for 10 weeks was not superior to 7 weekly sessions of unsupervised home-based exercise for 10 weeks in improving the primary outcome, leg-extension power of the operated leg, at the primary endpoint 10 weeks after surgery in THR patients with lower pre-operative function.

TRIAL REGISTRATION

NCT01214954.

Does reduced movement restrictions and use of assistive devices affect rehabilitation outcome after total hip replacement? A non-randomized, controlled study

BACKGROUND

Improvements in surgical techniques and increase of femoral head size might have changed the rationale for movement restrictions after total hip replacement (THR).

AIM

To evaluate the influence of movement restrictions and assistive devices on rehabilitation after fast track THR.

DESIGN

Non-randomized, controlled study.

SETTING

Inpatient.

POPULATION

365 consecutively included THR patients.

METHODS

Patients included the 3 initial month of the study underwent rehabilitation with restrictions in hip movement and a standard package of assistive devices (restricted group). This group was compared to patients included the following 3 months with less restricted hip movement and use of assistive devices according to individual needs (unrestricted group). Questionnaires on function, pain, quality of life (HOOS), anxiety (HADS), working status and patient satisfaction were completed before THR, 3 and 6 weeks after.

RESULTS

The HOOS function score at the 3 measurement times was (mean ± SD); unrestricted group: 46 ± 17 - 76 ± 9 - 83 ± 14 compared to restricted group: 43 ± 16 - 81 ± 14 - 83 ± 13. Changes over time was significantly higher in the restricted group (P=0.004). Return to work 6 weeks after THR for the unrestricted group compared to restricted group was: 53% versus 32% (P=0.045). No significant differences between groups in pain, symptoms, quality of life, anxiety/depression, hip dislocations and patient satisfaction.

CONCLUSION

This study showed slightly slower recovery in patient-reported function after reduction in movement restrictions and use of assistive devices, but the difference was eliminated after 6 weeks. Reduced movement restrictions did not affect the other patient-reported outcomes and led to earlier return to work.

CLINICAL REHABILITATION IMPACT

It is possible to reduce movement restrictions and use of assistive devices considerably. More research on safety issues is needed to elucidate the effect of unrestricted rehabilitation on hip dislocation.

MicroCT with energy-resolved photon-counting detectors

The goal of this paper was to investigate the benefits that could be realistically achieved on a microCT imaging system with an energy-resolved photon-counting x-ray detector. To this end, we built and evaluated a prototype microCT system based on such a detector. The detector is based on cadmium telluride (CdTe) radiation sensors and application-specific integrated circuit (ASIC) readouts. Each detector pixel can simultaneously count x-ray photons above six energy thresholds, providing the capability for energy-selective x-ray imaging. We tested the spectroscopic performance of the system using polychromatic x-ray radiation and various filtering materials with K-absorption edges. Tomographic images were then acquired of a cylindrical PMMA phantom containing holes filled with various materials. Results were also compared with those acquired using an intensity-integrating x-ray detector and single-energy (i.e. non-energy-selective) CT. This paper describes the functionality and performance of the system, and presents preliminary spectroscopic and tomographic results. The spectroscopic experiments showed that the energy-resolved photon-counting detector was capable of measuring energy spectra from polychromatic sources like a standard x-ray tube, and resolving absorption edges present in the energy range used for imaging. However, the spectral quality was degraded by spectral distortions resulting from degrading factors, including finite energy resolution and charge sharing. We developed a simple charge-sharing model to reproduce these distortions. The tomographic experiments showed that the availability of multiple energy thresholds in the photon-counting detector allowed us to simultaneously measure target-to-background contrasts in different energy ranges. Compared with single-energy CT with an integrating detector, this feature was especially useful to improve differentiation of materials with different attenuation coefficient energy dependences.

The norepinephrine transporter gene is a candidate gene for panic disorder

Panic disorder (PD) is an anxiety disorder characterized by recurrent panic attacks with a lifetime prevalence of 4.7%. Genetic factors are known to contribute to the development of the disorder. Several lines of evidence point towards a major role of the norepinephrine system in the pathogenesis of PD. The SLC6A2 gene is located on chromosome 16q12.2 and encodes the norepinephrine transporter (NET), responsible for the reuptake of norepinephrine into presynaptic nerve terminals. The aim of the present study was to analyze genetic variants located within the NET gene for association with PD. The case-control sample consisted of 449 patients with PD and 279 ethnically matched controls. All cases fulfilled the ICD-10 diagnostic criteria for PD. Genotyping was performed using the Sequenom platform (Sequenom, Inc, San Diego, USA). To test for allelic and haplotypic association, the PLINK software was used, and COMBASSOC was applied to test for gene-wise association. After quality control 29 single nucleotide polymorphisms (SNPs) spanning the gene-region were successfully analyzed. Seven SNPs located within the 5' end of the gene were significantly associated with PD. Furthermore, the NET gene showed overall evidence for association with the disease (P = 0.000035). In conclusion, the present study indicates that NET could be a susceptibility gene for PD.

Impact of the CYP2D6 genotype on post-operative intravenous oxycodone analgesia

BACKGROUND

Oxycodone is a semi-synthetic opioid with a mu-receptor agonist-mediated effect in several pain conditions, including post-operative pain. Oxycodone is metabolized to its active metabolite oxymorphone by O-demethylation via the polymorphic CYP2D6. The aim of this study was to investigate whether CYP2D6 poor metabolizers (PMs) yield the same analgesia post-operatively from intravenous oxycodone as extensive metabolizers (EMs).

METHODS

Two hundred and seventy patients undergoing primarily thyroid surgery or hysterectomy were included and followed for 24 h post-operatively. The CYP2D6 genotype was blinded until study procedures had been completed for all patients. All patients received intravenous oxycodone as pain treatment for 24 h post-operatively and morphine 5 mg was used as escape medication. A responder was characterized as a patient without the need for escape medication and a positive evaluation in a questionnaire 24 h post-operatively.

RESULTS

Twenty-four patients were PM (8.9%) and 246 were EM (91.1%). One PM (4.17%, CI=0.1-21.1) was a non-responder and 42 EM (17.07%, CI=12.6-22.4) were non-responders. The non-responder rate did not differ between the two genotypes (P=0.14). There was no difference in the total consumption of oxycodone between the two genotypes (EM=14.7 mg, CI=13.0-16.4 and PM=13.0 mg, CI=8.9-17.0, P=0.42). The mean oxymorphone/oxycodone ratios were 0.0031 and 0.00081 in the EMs and PMs, respectively (P<0.0001).

CONCLUSION

This study showed for the first time in patients that the oxymorphone formation depends on CYP2D6, but we found no difference in the post-operative analgesic effect of intravenous oxycodone between the two CYP2D6 genotypes.

Incidence of respiratory sensitisation and allergy to enzymes among employees in an enzyme producing plant and the relation to exposure and host factors

OBJECTIVES

Belonging to the group of high molecular weight respiratory sensitisers, microbial enzymes have been reported as a well known cause of occupational allergy, typically manifesting itself as rhinitis and/or asthma. High exposure to such high molecular weight sensitisers, and possibly also peak exposures, implies a higher risk than low exposure, but the exact relation between exposure, sensitisation and clinical allergy remains to be clarified. The authors sought to estimate the risk of respiratory enzyme allergy in an enzyme producing plant and to assess the relation between exposure indices and allergy.

METHODS

Retrospective follow-up study based upon data gathered from health surveillance since 1970. 1207 employees from production and laboratories were included. The level of enzyme exposure in the relevant departments was estimated retrospectively into five exposure levels based on 10-fold increments/decrements of the threshold limit value and other exposure information. The risk was estimated in an exponential regression survival model fitted with constant intensity for subperiods of time using maximum likelihood estimation.

RESULTS

During the first three years of a person's employment, the enzyme sensitisation and allergy incidence rates were 0.13 and 0.03 per person-year at risk, respectively. In the fitted models, exposure class did not correlate with the outcome variables. The risk of sensitisation decreased along the three decades, whereas the risk of allergy remained unchanged. The risk of sensitisation and allergy was doubled among smokers. Pre-employment atopy was only associated with sensitisation risk.

CONCLUSION

Sensitisation to enzymes decreased during the study period, possibly reflecting improvements in the working environment. A similar decrease could not be demonstrated for allergy to enzymes. Neither of the two outcomes correlated with exposure estimates, possibly because of the low precision of the estimates.

Computer mouse use predicts acute pain but not prolonged or chronic pain in the neck and shoulder

BACKGROUND

Computer use may have an adverse effect on musculoskeletal outcomes. This study assessed the risk of neck and shoulder pain associated with objectively recorded professional computer use.

METHODS

A computer programme was used to collect data on mouse and keyboard usage and weekly reports of neck and shoulder pain among 2146 technical assistants. Questionnaires were also completed at baseline and at 12 months. The three outcome measures were: (1) acute pain (measured as weekly pain); (2) prolonged pain (no or minor pain in the neck and shoulder region over four consecutive weeks followed by three consecutive weeks with a high pain score); and (3) chronic pain (reported pain or discomfort lasting more than 30 days and "quite a lot of trouble" during the past 12 months).

RESULTS

Risk for acute neck pain and shoulder pain increased linearly by 4% and 10%, respectively, for each quartile increase in weekly mouse usage time. Mouse and keyboard usage time did not predict the onset of prolonged or chronic pain in the neck or shoulder. Women had higher risks for neck and shoulder pain. Number of keystrokes and mouse clicks, length of the average activity period, and micro-pauses did not influence reports of acute or prolonged pain. A few psychosocial factors predicted the risk of prolonged pain.

CONCLUSIONS

Most computer workers have no or minor neck and shoulder pain, few experience prolonged pain, and even fewer, chronic neck and shoulder pain. Moreover, there seems to be no relationship between computer use and prolonged and chronic neck and shoulder pain.

Risk factors for hand-wrist disorders in repetitive work

OBJECTIVES

To identify the risk of hand-wrist disorders related to repetitive movements, use of hand force and wrist position in repetitive monotonous work.

METHODS

Using questionnaires and physical examinations, the prevalence and incidence of hand-wrist pain and possible extensor tendonitis (wrist pain and palpation tenderness) were determined in 3123 employees in 19 industrial settings. With the use of questionnaires and video recordings of homogenous work tasks number of wrist movements, hand force requirements and wrist position were analysed as risk factors for hand-wrist disorders, controlling for potential personal and psychosocial confounders. All participants were re-examined three times during a follow-up period of three years.

RESULTS

Force but not repetition and position was related to hand-wrist pain and possible tendonitis in the baseline analyses showing an exposure-response pattern. Odds ratios for the risk of hand pain was 1.7 (95% CI 1.3 to 2.2) and for possible tendonitis 1.9 (95% CI 1.1 to 3.3). There was no significant interaction between the ergonomic factors. In the follow-up analyses force remained a risk factor for hand pain (OR 1.4, 95% CI 1.1 to 1.8) and for possible tendonitis (OR 2.9, 95% CI 1.3 to 6.8). Repetition was also a risk factor for the onset of hand-wrist pain (OR 1.6, 95% CI 1.2 to 2.3).

CONCLUSIONS

Increasing levels of force were associated with prevalent and incident hand-wrist pain and possible extensor tendonitis. The results for repetition were less consistent. Working with the hand in a non-neutral position could not be identified as a risk factor.

The effect of gabapentin on post-operative pain following tonsillectomy in adults

BACKGROUND

The aim of the present study was to investigate whether a combination of rofecoxib and gabapentin could improve pain relief and reduce opioid requirements, compared with rofecoxib alone, during the first 5 days after tonsillectomy.

METHODS

In a randomized, double-blind, placebo-controlled study, 49 patients received gabapentin 1200 mg pre-operatively, followed by gabapentin 2 x 600 mg on the day of operation and gabapentin 3 x 600 mg for the next 5 days, or placebo. Both groups were given rofecoxib 50 mg daily. In the post-operative care unit, intravenous morphine was administered in doses of 2.5 mg on request. From 4 h to 5 days post-operatively, ketobemidone was offered as escape drug. Pain at rest and during swallowing, and side-effects, were assessed using a four-point verbal rating scale.

RESULTS

As a result of the global withdrawal of rofecoxib, the study had to be terminated prematurely. This report comprises the results from 22 patients in the gabapentin group and 27 patients in the placebo group. Gabapentin reduced ketobemidone requirements during the first 24 h post-operatively [4.5 mg (standard deviation, 3.0 mg) in the placebo group vs. 2.0 mg (standard deviation, 2.0 mg) in the gabapentin group; P < 0.003]. Gabapentin induced more dizziness (P < 0.002), gait disturbance (P < 0.02) and vomiting (P < 0.05) during days 0-5 than placebo. No other statistically significant differences were observed.

CONCLUSION

Gabapentin reduced opioid requirements in the first 24 h after tonsillectomy. The benefits of the reduced opioid intake may be overshadowed by the drawbacks of side-effects.

Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?

BACKGROUND

Pain in the neck and upper extremity is reported with high frequency in repetitive work. Mechanical overload of soft tissues seems a plausible mechanism, but psychological factors have received considerable attention during the past decade. If psychological factors are important for development of regional pain in repetitive work, stress symptoms would likely be on the causal path.

AIMS

To examine whether objective measures of repetitive monotonous work are related to occurrence and development of stress symptoms.

METHODS

In 1994-95, 2033 unskilled workers with continuous repetitive work and 813 workers with varied work were enrolled. Measures of repetitiveness and force requirements were quantified using video observations to obtain individual exposure estimates. Stress symptoms were recorded at baseline and after approximately one, two, and three years by the Setterlind Stress Profile Inventory.

RESULTS

Repetitive work, task cycle time, and quantified measures of repetitive upper extremity movements including force requirements were not related to occurrence of stress symptoms at baseline or development of stress symptoms during three years of follow up.

CONCLUSIONS

The findings do not indicate that repetitive work is associated with stress symptoms, but small effects cannot be ruled out. Thus the results question the importance of mental stress mechanisms in the causation of regional pain related to repetitive work. However, the findings should be interpreted with caution because the stress inventory has not been validated against a gold standard.

Tingling/numbness in the hands of computer users: neurophysiological findings from the NUDATA study

OBJECTIVES

To investigate whether tingling/numbness of the hands and fingers among computer users is associated with elevated vibration threshold as a sign of early nerve compression.

METHODS

Within the Danish NUDATA study, vibratory sensory testing with monitoring of the digital vibration threshold at seven frequencies on the second and fifth fingers of both hands was performed on 20 cases with unilateral tingling/numbness in the hands and fingers, and 20 gender- and age-matched controls. Both cases and controls were identified from questionnaire information about tingling/numbness at least once a week or daily within the last 3 months. Participants with more than slight muscular pain or disorders of the neck and upper extremities, excessive alcohol consumption, previous injuries of the upper extremities, or concurrent medical diseases were excluded. The two groups had a similar amount of work with mouse, keyboard, and computer.

RESULTS

Seven of the 20 cases (35%) had elevated vibration thresholds, compared with 3 of the 20 controls (15%); this difference was not statistically significant (chi2=2.13, P=0.14). Compared with controls, cases had increased perception threshold for all frequencies, but the difference was statistically significant for only 2 out of 14 measurements. Comparison between left and right hand threshold values within the case group did not show any significant difference at any frequency.

CONCLUSIONS

The results indicate that tingling/numbness of the hands and fingers among computer users cannot be explained by nerve compression.

Does computer use pose an occupational hazard for forearm pain; from the NUDATA study

AIMS

To determine the occurrence of pain conditions and disorders in the forearm and to evaluate risk factors for forearm pain in a cohort of computer workers.

METHODS

A total of 6943 participants with a wide range of computer use and work tasks were studied. At baseline and at one year follow up participants completed a questionnaire. Participants with relevant forearm symptoms were offered a clinical examination. Symptom cases and clinical cases were defined on the basis of self reported pain score and palpation tenderness in the muscles of the forearm.

RESULTS

The seven days prevalence of moderate to severe forearm pain was 4.3%. Sixteen of 296 symptom cases met criteria for being a clinical forearm case, and 12 had signs of potential nerve entrapment. One year incidence of reported symptom cases was 1.3%; no subjects developed new signs of nerve entrapment. Increased risk of new forearm pain was associated with use of a mouse device for more than 30 hours per week, and with keyboard use more than 15 hours per week. High job demands and time pressure at baseline were risk factors for onset of forearm pain; women had a twofold increased risk of developing forearm pain. Self reported ergonomic workplace factors at baseline did not predict future forearm pain.

CONCLUSION

Intensive use of a mouse device, and to a lesser extent keyboard usage, were the main risk factors for forearm pain. The occurrence of clinical disorders was low, suggesting that computer use is not commonly associated with any severe occupational hazard to the forearm.

Prognosis of shoulder tendonitis in repetitive work: a follow up study in a cohort of Danish industrial and service workers

BACKGROUND

The physical and psychosocial work environment is expected to modify recovery from shoulder disorders, but knowledge is limited.

METHODS

In a follow up study of musculoskeletal disorders in industrial and service workers, 113 employees were identified with a history of shoulder pain combined with clinical signs of shoulder tendonitis. The workers had yearly re-examinations up to three times. Quantitative estimates of duration, repetitiveness, and forcefulness of current tasks were obtained from video recordings. Perception of job demands, decision latitude, and social support was recorded by a job content questionnaire. Recovery of shoulder tendonitis was analysed by Kaplan-Meier survival technique and by logistic regression on exposure variables and individual characteristics in models, allowing for time varying exposures.

RESULTS

Some 50% of workers recovered within 10 months (95% CI 6 to 14 months). Higher age was strongly related to slow recovery, while physical job exposures were not. Perception of demands, control, and social support at the time when the shoulder disorder was diagnosed, were associated with delayed recovery, but these psychosocial factors did not predict slow recovery in incident cases identified during follow up.

CONCLUSION

The median duration of shoulder tendonitis in a cross sectional sample of industrial and service workers was in the order of 10 months. This estimate is most likely biased towards too high a value. Recovery was strongly reduced in higher age. Physical workplace exposures and perceived psychosocial job characteristics during the period preceding diagnosis seem not to be important prognostic factors.

Risk factors in the onset of neck/shoulder pain in a prospective study of workers in industrial and service companies

AIMS

To quantify the relative contribution of work related physical factors, psychosocial workplace factors, and individual factors and aspects of somatisation to the onset of neck/shoulder pain.

METHODS

Four year prospective cohort study of workers from industrial and service companies in Denmark. Participants were 3123 workers, previously enrolled in a cross sectional study, where objective measurement of physical workplace factors was used. Eligible participants were followed on three subsequent occasions with approximately one year intervals. Outcomes of interest were: new onset of neck/shoulder pain (symptom cases); and neck/shoulder pain with pressure tenderness in the muscles of the neck/shoulder region (clinical cases).

RESULTS

During follow up, 636 (14.1%) participants reported neck/shoulder pain of new onset; among these, 82 (1.7%) also had clinical signs of substantial muscle tenderness. High shoulder repetition was related to being a future symptom case, and a future clinical case. Repetition was strongly intercorrelated with other physical measures. High job demands were associated with future status as a symptom case, and as a clinical case. A high level of distress predicted subsequent neck/shoulder pain, and neck/shoulder pain with pressure tenderness.

CONCLUSIONS

High levels of distress, and physical and psychosocial workplace factors are predictors of onset of pain in the neck and/or shoulders, particularly pain with pressure tenderness in the muscles.

Interview data versus questionnaire data in the diagnosis of carpal tunnel syndrome in epidemiological studies

AIMS

In most epidemiological studies on carpal tunnel syndrome (CTS), the case definition is based on questionnaire data with or without neurophysiological testing. The aim of this study was to test if the use of questionnaire data results in misclassification of cases.

METHODS

In two studies, involving 940 and 311 participants, respectively, the people indicating CTS symptoms (tingling) in a questionnaire were clinically interviewed. In a subpopulation (n = 404), all went through an interview regardless of their questionnaire answers.

RESULTS

Only 35-45% of the participants reporting tingling once a week or more in the questionnaire actually had symptoms consistent with CTS when interviewed. The remaining 55-65% had no or infrequent symptoms or symptoms because of other disorders. Few potential CTS cases were missed. The positive predictive values were 0.48 (95% CI = 0.30-0.66) and 0.52 (95% CI = 0.38-0.67) on the right and left hands, respectively. The sensitivities, specificities and negative predictive values ranged from 0.87 to 1.00.

CONCLUSIONS

Questionnaire information overestimates the prevalence of CTS symptoms. However, asking about tingling in a questionnaire is a simple and sensitive first step to detect potential CTS cases, but symptoms should be confirmed by interview.

Impaction allografting for femoral revision hip arthroplasty. Mid-term results after minimum five year follow-up in 46 cases

Previously, only short-term follow-up results after femoral revision using impacted allograft and cemented stems the exchange technique have been published. We present the results of 46 femoral exchange revision procedures performed on 42 patients with five to nine years follow-up. At follow-up, five patients had died and two patients did not complete follow-up. Two patients were re-revised. One patient underwent re-revision due to early collapse of the impaction construct. In another patient, stem loosening due to acetabular revision occurred and a full re-revision of the impaction area was performed. One patient suffered late post-operative femoral fracture and three patients experienced hip dislocations. Ninety percent expressed satisfaction with the result. Harris Hip Score (HHS) improved from 36 to 82 (p < 0.001). Radiographically, one patient demonstrated stem subsidence of greater than 5mm. Eighty-six percent demonstrated signs of graft incorporation and only one patient demonstrated signs of loosening. Our results after a minimum of five years follow-up of patients surgically treated with the exchange femoral revision technique demonstrated good clinical and radiological results. With a re-revision rate of 4.3%, one case with subsidence exceeding 5 mm and one case with diaphyseal fracture, we did not observe the problems of subsidence and femoral fractures described in previous studies. (Hip International 2002; 4: 357-64).

Effect of intravenous magnesium on pain and secondary hyperalgesia associated with the heat/capsaicin sensitization model in healthy volunteers

We investigated the effects of i.v. magnesium on secondary hyperalgesia following heat/capsaicin stimulation in human volunteers. Twenty-five volunteers were included in this double blind, randomized, crossover study. Sensitization was induced in the volunteers, who were then subjected to either i.v. saline or magnesium sulphate. No analgesic or antihyperalgesic effect could be demonstrated in sensitized skin during infusion of magnesium. In contrast, painfulness of thermal stimulation was increased in normal skin. These results suggest that i.v. magnesium has no important analgesic effects in clinically relevant doses.

Physical exposure assessment in monotonous repetitive work--the PRIM study

OBJECTIVES

A program called the Project on Research and Intervention in Monotonous Work (PRIM) was initiated in 1994 as a prospective cohort study of work-related musculoskeletal disorders. The group-based exposure assessment strategy, focusing on task-related exposure and used to obtain baseline measures of physical exposures, is reported in this paper.

METHODS

Monotonous, repetitive worktasks were evaluated at 19 factories. Tasks with an estimated similarity in physical exposure were aggregated before 103 exposure groups were formed. Subjects from the exposure groups were randomly sampled for measurements, and task-related exposure levels were quantified by 43 single exposure items using a real-time video-based observation method that allowed computerized estimates of repetitiveness, body postures, force, and velocity. In combination with questionnaire-based data on task distribution, the duration of exposure was calculated at the individual level.

RESULTS

The video-based observational method and the large number of exposure variables enabled the establishment of detailed quantitative exposure profiles in 103 task-based exposure groups. However, methodological problems associated with the use of grouped exposure assessment were revealed. Despite efforts to optimize group homogeneity, the within-group variance was larger than the between-group variance for several shoulder postural variables.

CONCLUSIONS

A task-based exposure-assessment strategy can be successful in solving some of the main problems associated with the assessment of physical workplace exposures. The large within-group variance in exposure to nonneutral shoulder postures may eventually require individual assessment or the inclusion of groups with maximal contrast in exposure or both.

Effect of oral ketamine on secondary hyperalgesia, thermal and mechanical pain thresholds, and sedation in humans

BACKGROUND AND OBJECTIVES

Ketamine is an N-methyl-D-aspartate (NMDA) receptor antagonist, and has been proven effective in alleviating secondary hyperalgesia in human subjects when injected intravenously. After oral ingestion, ketamine is metabolized into norketamine, which in vitro possesses NMDA receptor antagonistic effect. The aim of this study was to investigate the effects of oral administration of ketamine on secondary hyperalgesia evoked by standardized tissue injury.

METHODS

Twenty-four male volunteers were included in the study. Each volunteer received the following treatment regimen, in randomized, double-blind, 3-way cross-over fashion: (A) placebo; (B) ketamine, 0.5 mg/kg; and (C) ketamine, 1.0 mg/kg. Standardized tissue injury was induced after study medication by heating the right calf with a rectangular thermode. The temperature was 47 degrees C, and heating time was 7 minutes. The following parameters were investigated: Pain during induction of the burn injury; heat-pain detection thresholds in the injured area and a corresponding noninjured area; secondary hyperalgesia surrounding the injured area on the calf; secondary hyperalgesia induced by heating an area on the thigh with 45 degrees C in 3 minutes; pressure-pain detection thresholds measured on the middle phalanx of the 4th left finger; pain during a 60-second thermal stimulation of 46 degrees C on undamaged skin on the left thigh; and side effects.

RESULTS

Some degree of sedation was observed after oral administration of ketamine. No effects on any of the other investigated parameters were observed.

CONCLUSION

Oral ketamine 0.5 or 1.0 mg/kg has no effect on secondary hyperalgesia or thermal or mechanical pain thresholds in human volunteers.

Work-related knee disorders in floor layers and carpenters

Previous studies indicate an increased prevalence of knee disorders in some occupations possibly related to kneeling working positions. The purpose of the present study was to examine the relationship among knee-straining work, self-reported knee-complaints, and physical signs of knee disorders. The duration of knee-straining work was estimated from videotapes of representative work tasks. Floor layers (n = 133), carpenters (n = 506), and compositors (n = 327) aged 26 to 72 years without previous acute knee traumas were examined in a cross-sectional study by questionnaire. A stratified random sample of the questionnaire responders; 67 floor layers, 127 carpenters, and 101 compositors had independent double examinations for physical signs of knee disorders. The videotapes showed that knee-straining work constituted 56% of working time for floor layers, 26% for carpenters, and none for compositors. The prevalences of self-reported knee-complaints were positively associated with the amount of knee-straining work and were significantly different for the three trades. Floor layers and carpenters who were presently working in their trade had a higher prevalence of knee complaints than floor layers and carpenters who had left their trade. Age, seniority, weight, body mass index, smoking, and knee-straining sports activity had no significant effects. The clinical study showed a positive association for knee-straining work, hyperkeratosis, and bursitis. A similar pattern was found for signs of intraarticular knee disorders by one physician but not by another. The reproducibility of these signs was low. More studies are needed to define clinically important knee disorders for epidemiological studies.

Radiographic knee osteoarthritis in floorlayers and carpenters

OBJECTIVES

The aim of the present study was to examine the relationship between knee-straining work and radiological findings of knee osteoarthritis and to study the relation between radiological findings and self-reported knee complaints and clinical signs of knee osteoarthritis.

METHODS

The material consisted of 133 floorlayers, 506 carpenters, and 327 compositors, 26-72 years of age, who had completed a questionnaire and reported no previous knee trauma. A stratified sample of these questionnaire respondents, 50 floorlayers, 51 carpenters, and 49 compositors, were radiologically examined for knee osteoarthritis by 2 radiologists. The X-ray films were independently assessed by 2 radiologists and blinded with respect to knee complaints, trade, and age.

RESULTS

The radiological investigation showed estimated prevalences of knee-osteoarthritis (grades 2-4) for 14% of the floorlayers, 8% of the carpenters, and 6% of the compositors (not significantly different). For the subjects > or =50 years of age the estimated prevalences of the combination of radiological grades 2-4 for knee osteoarthritis and knee complaints during the last 12 months were 29% [95% confidence interval (95% CI) 17-44%], 9% (95% CI 1-26%), and 1% (95% CI 1-10%) for the floorlayers, carpenters, and compositors, respectively. Radiological grades 2-4 were mainly found for subjects above the age of 50 years, subjects with knee complaints, and floorlayers. Radiological knee osteoarthritis was positively associated with self-reported knee complaints and with clinical signs of intraarticular and retropatellar crepitation.

CONCLUSIONS

The data suggest that work in which a considerable amount of time is spent in knee-straining positions may be a risk factor for the development of knee osteoarthritis above the age of 50 years.

Human papillomavirus type 16 E7-regulated genes: regulation of S100P and ADP/ATP carrier protein genes identified by differential-display technology

Human papillomavirus type 16 (HPV-16) is the dominant risk factor for the development of cervical cancer. The virus encodes three oncoproteins, of which the E7 oncoprotein is the major protein involved in cell immortalization and transformation. E7 is a multi-functional protein. It binds the retinoblastoma tumour-suppressor protein (pRb), which regulates progression through the G(1) restriction point in the cell cycle. The E7 protein interacts with transcription-regulatory proteins such as the TATA box-binding protein and with proteins of the AP1 transcription factor family. To identify additional proteins regulated by E7, differential-display PCR was used to identify differentially expressed mRNAs in cells containing an inducible E7 protein. It is reported that E7 expression leads to regulation of the genes encoding the calcium-binding protein S100P and the mitochondrial ADP/ATP carrier protein. These data identify new functions of the E7 protein and thus expand the number of routes by which HPV-16 influences cell growth control, although the function of S100P has still to be elucidated.

Validity of self-reporting and video-recording for measuring knee-straining work postures

The aim of this study was to compare the validity of self-reporting and video-recording as methods of measuring the duration of knee-straining work postures, and to evaluate the reproducibility of timings of the video-recordings. Thirty-nine carpenters and 33 floorlayers were video-filmed while working, and were asked immediately afterwards to quantify the amount of time spent in knee-straining positions. The investigators recorded the periods of knee-straining work with a stopwatch during playback of the video-film, and the agreement between the two investigators' measurements was studied in 13 pairs of measurements. The video-observation method was very effective for timing knee-strain work. Furthermore, Spearman's correlation coefficient (0.88) indicated a good association between observed and self-reported knee-straining work. Estimation of self-reported knee-straining work collected by interview showed good correlation with measurements of video-recordings. When judging the repeatability of timings of knee-straining work from the video-recordings, a high level of agreement was seen between the two observers in the 13 dual measurements of time spent in knee-straining work positions.

Half life of chromium in serum and urine in a former plasma cutter of stainless steel

For 8 years chromium in serum and urine has been followed up in a former plasma cutter of stainless steel who was exposed to airborne dust and fumes containing chromium during this work. After the first examination for serum chromium the exposure ended. Serum chromium concentration has been measured seven times during the period and was initially very high and has subsequently dropped slowly. The half life was 40 months in serum. Urinary chromium has been measured five times. The half life was 129 months in urine. The study shows that exposure to airborne dust and fumes containing chromium may cause accumulation of chromium in the body, and that when exposure ends, elimination of chromium is very slow. Previous studies suggest that chromium mainly accumulates in the lungs.

A systematic review of intra-articular local anesthesia for postoperative pain relief after arthroscopic knee surgery

BACKGROUND AND OBJECTIVES

In a systematic review, we have evaluated double-blind, randomized, controlled trials of intra-articular local anesthesia compared with placebo or no treatment in the control of postoperative pain after arthroscopic knee surgery.

METHODS

Outcome measures were pain scores, supplementary analgesics, and time to first analgesic request. Efficacy was estimated by significant difference (P < .05) as reported in the original reports and by calculation of the weighted mean difference of pain scores between treatment groups.

RESULTS

Twenty studies with data from 895 patients were considered appropriate for analysis. Twelve of these 20 studies showed improved pain relief after intra-articular local anesthesia in at least one of the considered pain parameters, whereas the eight other studies were without such improvements. In ten of the positive studies, pain scores were significantly lower in the treatment groups compared with the control groups with visual analog scale (VAS) score reductions of between 10 and 35 mm early (1-4 hours) postoperatively. Quantitative analysis with calculation of the weighted mean difference in VAS confirmed a statistically significant but minor clinically important effect on postoperative pain scores. In nine studies, the consumption of supplementary analgesics was reduced 10-50% during observation periods of up to 4 hours; however, in most cases, the analgesic requirements were small to moderate. Only in two of six studies, where time to first analgesic request was evaluated, a significant prolongation of pain relief was observed as lasting between 30 and 50 minutes.

CONCLUSIONS

There is a weak evidence for a reduction of postoperative pain after intra-articular local anesthesia in patients undergoing arthroscopic knee surgery, which although being sinall to moderate and of short duration, may be of clinical significance in day-case surgery.

The effect of naloxone on ketamine-induced effects on hyperalgesia and ketamine-induced side effects in humans

BACKGROUND

The (NMDA) receptor plays a significant role in wind-up and spinal hypersensitivity and is involved in the occurrence of secondary hyperalgesia. Ketamine is an NMDA-receptor antagonist and has proven effective in alleviating secondary hyperalgesia in humans. Although it is disputed, the actions of ketamine have been ascribed not only to NMDA receptor antagonism, but also to opioid receptor agonism. A study therefore was designed in which the abolishment of a previously demonstrated effect of ketamine on secondary hyperalgesia was sought by pretreatment with naloxone.

METHODS

Twenty-five volunteers were subjected to three treatment regimens. A standardized first-degree burn injury was induced. On appearance of primary and secondary hyperalgesia, one of the following infusion schemes was applied in a randomized, double-blind, cross-over fashion: (1) infusion of naloxone (0.8 mg/15 min followed by 0.4 mg/h), succeeded by infusion of ketamine (0.3 mg x kg(-1) x 15 min(-1) followed by 0.3 mg x kg(-1) x h(-1)); (2) infusion of placebo, succeeded by infusion of ketamine (0.3 mg x kg(-1) x 15 min(-1) followed by 0.3 mg x kg(-1) x h(-1)); and (3) infusion of placebo, succeeded by infusion of placebo. Heat-pain detection thresholds, magnitude of secondary hyperalgesia around the burn injury, and side effects were determined.

RESULTS

Ketamine reduced secondary hyperalgesia. Naloxone did not affect the action of ketamine. The magnitudes of side effects were equal if the subjects received ketamine, regardless of preceding infusion of naloxone.

CONCLUSIONS

In this experimental setting, opioid receptor blockade does not inhibit ketamine-induced reductions of secondary hyperalgesia.

The Harris Design-2 total hip replacement fixed with so-called second-generation cementing techniques. A ten to fifteen-year follow-up

We analyzed the clinical results of 195 Harris Design-2 total hip replacements performed with so-called second-generation cementing techniques in 166 consecutive patients who had osteoarthrosis. The mean age of the patients at the time of the replacement was sixty-seven years and nine months (range, thirty-one to eighty-nine years). Forty-eight patients (fifty-four hips) died before the time of the latest follow-up, but the implants were apparently functioning well at the time of death. Three patients (four hips) were lost to follow-up. Five patients (five hips; 3 percent) had a revision because of aseptic loosening of the acetabular or femoral component, or both, that was related to wear-induced osteolysis. The mean Harris hip score for the 131 hips that were available at the latest follow-up examination at a mean of twelve years (range, ten to fifteen years) after the operation was 89 +/- 10 points. On the basis of the Harris hip score, seventy-six hips had an excellent result, thirty-four had a good result, fifteen had a fair result, and six had a poor result at the latest follow-up examination. Radiographically, twelve (9 percent) of the 131 acetabular components and three (2 percent) of the 131 femoral components were probably or definitely loose. At a mean of twelve years, 186 (97 percent) of 191 Harris Design-2 implants were in situ or had been in situ at the time of the patient's death.

A qualitative systematic review of incisional local anaesthesia for postoperative pain relief after abdominal operations

In a qualitative systematic review, we have evaluated randomized controlled trials (RCT) of incisional local anaesthesia compared with placebo or no treatment in the control of postoperative pain after open abdominal operations. Twenty-six studies with data from 1211 patients were considered appropriate for analysis. Five RCT considered inguinal herniotomy, four hysterectomy, eight cholecystectomy and nine studies a variety of surgical procedures. Outcome measures were pain scores, supplementary analgesics and time to first analgesic request. Efficacy was estimated by significant difference (P < 0.05), as reported in the original investigation. All studies of herniotomy showed a 2-7-h duration of clinically relevant improved pain relief. Results of hysterectomy studies were inconclusive, with two being negative. Five of the cholecystectomy studies showed significant differences but questionable clinical importance and validity in three. In various other procedures results were inconsistent and in some of minor clinical importance. Except for herniotomy, there was a lack of evidence for effect of incisional local anaesthesia on postoperative pain and further standardized studies are needed before recommendations can be made.