Assessment of radiologic progression in rheumatoid arthritis. A randomized, controlled trial

Deep learning-based automatic-bone-destruction-evaluation system using contextual information from other joints

BACKGROUND

X-ray images are commonly used to assess the bone destruction of rheumatoid arthritis. The purpose of this study is to propose an automatic-bone-destruction-evaluation system fully utilizing deep neural networks (DNN). This system detects all target joints of the modified Sharp/van der Heijde score (SHS) from a hand X-ray image. It then classifies every target joint as intact (SHS = 0) or non-intact (SHS ≥ 1).

METHODS

We used 226 hand X-ray images of 40 rheumatoid arthritis patients. As for detection, we used a DNN model called DeepLabCut. As for classification, we built four classification models that classify the detected joint as intact or non-intact. The first model classifies each joint independently, whereas the second model does it while comparing the same contralateral joint. The third model compares the same joint group (e.g., the proximal interphalangeal joints) of one hand and the fourth model compares the same joint group of both hands. We evaluated DeepLabCut's detection performance and classification models' performances. The classification models' performances were compared to three orthopedic surgeons.

RESULTS

Detection rates for all the target joints were 98.0% and 97.3% for erosion and joint space narrowing (JSN). Among the four classification models, the model that compares the same contralateral joint showed the best F-measure (0.70, 0.81) and area under the curve of the precision-recall curve (PR-AUC) (0.73, 0.85) regarding erosion and JSN. As for erosion, the F-measure and PR-AUC of this model were better than the best of the orthopedic surgeons.

CONCLUSIONS

The proposed system was useful. All the target joints were detected with high accuracy. The classification model that compared the same contralateral joint showed better performance than the orthopedic surgeons regarding erosion.

Should radiographic progression still be used as outcome in RA?

Radiographs of hands and feet are traditionally the images that are used to assess structural damage progression in drug trials in patients with rheumatoid arthritis, aiming at proving the disease modifying capacity of a drug. Although treatment has largely improved over the past decade and consequently radiographic progression is limited in control arms in clinical trials, recent trials are still able to show inhibition of structural progression by new drugs. The requirements for the successful use of radiographic progression as an outcome in rheumatoid arthritis trials will be discussed in this paper.

Multireader assessment as an alternative to reference assessment to improve the detection of radiographic progression in a large longitudinal cohort of rheumatoid arthritis (ESPOIR)

INTRODUCTION

Structural damage progression is a major outcome in rheumatoid arthritis (RA). Its evaluation and follow-up in trials should involve radiographic scoring by 1 or 2 readers (reference assessment), which is challenging in large longitudinal cohorts with multiple assessments.

OBJECTIVES

To compare the reproducibility of multireader and reference assessment to improve the feasibility of detecting radiographic progression in a large cohort of patients with early arthritis (ESPOIR).

METHODS

We used 3 sessions to train 12 rheumatologists in radiographic scoring by the van der Heijde-modified Sharp score (SHS). Multireader scoring was based on 10 trained-reader assessments, each reader scoring a random sample of 1/5 of all available radiographs (for double scoring for each X-ray set) for patients included in the ESPOIR cohort with complete radiographic data at M0 and M60. Reference scoring was performed by 2 experienced readers. Scoring was performed blindly to clinical data, with radiographs in chronological order. We compared multireader and reference assessments by intraclass correlation coefficients (ICCs) for SHS and significant radiographic progression (SRP).

RESULTS

The intrareader and inter-reader reproducibility for trained assessors increased during the training sessions (ICC 0.79 to 0.94 and 0.76 to 0.92), respectively. For the 524 patients included, agreement between multireader and reference assessment of SHS progression between M0 and M60 and SRP assessment were almost perfect, ICC (0.88 (95% CI 0.82 to 0.93)) and (0.99 (95% CI 0.99 to 0.99)), respectively.

CONCLUSIONS

Multireader assessment of radiographic structural damage progression is comparable to reference assessment and could be used to improve the feasibility of radiographic scoring in large longitudinal cohort with numerous X-ray evaluations.

Reliability testing of the Larsen and Sharp classifications for rheumatoid arthritis of the elbow

BACKGROUND

Two popular systems for classifying rheumatoid arthritis affecting the elbow are the Larsen and Sharp schemes. To our knowledge, no study has investigated the reliability of these 2 systems. We compared the intraobserver and interobserver agreement of the 2 systems to determine whether one is more reliable than the other.

METHODS

The radiographs of 45 patients diagnosed with rheumatoid arthritis affecting the elbow were evaluated. Anteroposterior and lateral radiographs were deidentified and distributed to 6 evaluators (4 fellowship-trained upper extremity surgeons and 2 orthopedic trainees). Each evaluator graded all 45 radiographs according to the Larsen and Sharp scoring methods on 2 occasions, at least 2 weeks apart.

RESULTS

Overall intraobserver reliability was 0.93 (95% confidence interval [CI], 0.90-0.95) for the Larsen system and 0.92 (95% CI, 0.86-0.96) for the Sharp classification, both indicating substantial agreement. Overall interobserver reliability was 0.70 (95% CI, 0.60-0.80) for the Larsen classification and 0.68 (95% CI, 0.54-0.81) for the Sharp system, both indicating good agreement. There were no significant differences in the intraobserver or interobserver reliability of the systems overall and no significant differences in reliability between attending surgeons and trainees for either classification system.

CONCLUSION

The Larsen and Sharp systems both show substantial intraobserver reliability and good interobserver agreement for the radiographic classification of rheumatoid arthritis affecting the elbow. Differences in training level did not result in substantial variances in reliability for either system. We conclude that both systems can be reliably used to evaluate rheumatoid arthritis of the elbow by observers of varying training levels.

Iguratimod for the treatment of rheumatoid arthritis in Japan

Iguratimod (IGU), a small-molecule compound, was developed as a disease-modifying antirheumatic drug in Japan. The pharmacological studies showed that inhibition of the production of cytokines and immunoglobulins mainly contributes to its improvement effect on animal arthritis models. The first clinical study of IGU in Japanese patients with rheumatoid arthritis was started in 1992 and Phase III studies were started in 1998. From the results of Phase II studies, a dose-escalating regimen was recommended to relieve the side effects. In a double-blind study comparing the efficacy and safety of the drug with those of placebo and salazosulfapyridine, it was confirmed that IGU was superior to placebo and was not inferior to salazosulfapyridine. Furthermore, a double-blind controlled trial of IGU in combination with methotrexate revealed an efficacious and manageable safety profile. IGU would be widely used as a new option for rheumatoid arthritis treatment and combination drug with methotrexate.

Rheumatoid arthritis therapy reappraisal: strategies, opportunities and challenges

Rheumatoid arthritis (RA) is considered a chronic disease that cannot be cured. Biologic agents have enabled good therapeutic successes; however, the response to biologic therapy depends on treatment history and, especially, disease duration. In general, the more drug-experienced the patients, the lower the response rates, although this limitation can be overcome by promptly adjusting or switching treatment in a treat-to-target approach. Another challenge is the question of how long therapy should be continued once the treatment target, which should be remission or at least a state of low disease activity, has been reached. The data available suggest that, in most patients with established disease, cessation of biologic therapy will be followed by disease flares, whereas a reduction of dose or an increase in the interval between doses enables maintenance of treatment success. Induction therapy very early in the disease course followed by withdrawal of the biologic agent might also be a feasible approach to attain sustained good outcomes, but currently available data are not strong enough to allow for such a conclusion to be reached. Taken together, this underscores the importance of research into the cause(s) of RA so that curative therapies can be developed.

From inhibition of radiographic progression to maintaining structural integrity: a methodological framework for radiographic progression in rheumatoid arthritis and psoriatic arthritis clinical trials

Usually, a clinical trial in rheumatoid arthritis and psoriatic arthritis aiming to demonstrate that a new antirheumatic drug treatment can inhibit progression of structural damage has a ‘superiority design’: The new treatment is compared to placebo or to another active treatment. Currently, many new drug treatments have shown to be able to completely suppress progression (progression rates close to zero). For largely unknown reasons, during the last 10 years, radiographic progression rates in clinical trials have gradually decreased, so that progression rates in the comparator groups are often too low to demonstrate meaningful inhibition, and thus superiority of the new treatment. We here propose an alternative framework to demonstrate that new treatments have the ability to ‘preserve structural integrity’ rather than to ‘inhibit radiographic progression’. Anno 2013, preserving structural integrity is conceptually more realistic than inhibiting radiographic progression.

Chronological reading of radiographs in rheumatoid arthritis increases efficiency and does not lead to bias

OBJECTIVES

To evaluate the difference between chronological and random sequence reading in a series of radiographs with 11 years' follow-up. In addition, the influence of the starting point and length of series was evaluated.

METHODS

Two experienced readers independently and repeatedly scored digitised radiographs of 62 patients at time points 0, 2, 5, 8 and 11 years of follow-up from the COBRA follow-up database according to the Sharp/van der Heijde method. A linear mixed model was fitted to the data.

RESULTS

Over 11 years the mean scores increased by 3.8 points per year. Compared to random reading, chronological reading resulted in a slightly increased progression rate of 0.4 points per year (p=0.008) and a lower standard error of the mean total progression rate of 0.30 (compared to 0.35 for random reading). Over 11 years, this results in a small difference in progression estimates of about five points, but a highly relevant difference of over 25% of patients needed in a study to find a difference in radiological outcome between two groups. Reading of short series, or series including a baseline radiograph, results in a significantly higher yearly progression rate compared to reading of long series, or series not including a baseline measurement.

CONCLUSIONS

Chronological reading of radiographs is preferred above random reading, due to decreased variability around the estimation of the progression rate; this increased efficiency translates into smaller sample sizes, or increased power to detect small differences. For studies with long-term follow-up, the same two readers should read all radiographs, including baseline.

Bone mineral density changes in patients with recent-onset rheumatoid arthritis

Background:

Osteoporosis and related fragility fractures are one of the most common complications seen in patients with rheumatoid arthritis (RA) and dramatically affect quality of life.

Objective:

To evaluate changes in bone mineral density in patients with recent onset rheumatoid arthritis (<1 year) and its correlation if any with a modified DAS-28 score and simple erosion narrowing score (SENS).

Methods:

This study included 30 patients with recent-onset rheumatoid arthritis fulfilling the new American College of Rheumatology/European League Against Rheumatism diagnostic criteria for rheumatoid arthritis and 20 healthy volunteers as controls. All were subjected to a complete blood count, erythrocyte sedimentation rate, C-reactive protein, liver function tests, renal function tests, rheumatoid factor, and plain x-rays of the hands and feet. Dual-energy x-ray absorptiometry DEXA was used to measure bone mineral density (BMD) of the left proximal femur, lumbar spine (L1–L4), and lower distal radius at the time of recruitment.

Results:

In the RA patients, 13.3% had osteoporosis, 50% had osteopenia, and 36.7% had normal BMD. The most common site of osteoporosis was the lumbar spine (four patients, 13.3%) followed by the femur (two patients, 6.6%), and forearm (only one patient, 3.3%). There was a significantly higher percentage of osteoporosis among RA males than females and the difference was statistically significant (P = 0.009). Osteoporosis was more common in patients treated with corticosteroids and disease modifying antirheumatic drugs (DMARDs) than in patients treated with only nonsteroidal anti-inflammatory drugs (P = 0.004). Higher disease activity (DAS-28) was found in RA patients with osteoporosis compared to RA patients with normal BMD or osteopenia, but the difference was not statistically significant. Osteoporotic RA patients were found to have a higher SENS score for radiological damage than nonosteoporotic ones.

Conclusion:

BMD changes do occur in patients with early RA, and are not necessarily correlated with disease activity (DAS-28). However, a significant negative correlation was found between BMD and the score of radiological damage (SENS). Dual energy x-ray absorptiometry is an important investigation to assess BMD in early RA patients.

An overview of commonly used radiographic scoring methods in rheumatoid arthritis clinical trials

Despite the advent of magnetic resonance imaging and musculoskeletal ultrasound, the plain radiographs of the hands and feet remain an important tool for a practising rheumatologist both in clinical and research settings. This review focuses on providing a historical overview of commonly used methods of scoring radiographs in rheumatoid arthritis and discusses technical issues related to radiographic scoring, limitations and advantages of radiographs, and current recommendations regarding reporting radiographic data in clinical trials.

[Relationship between individual radiographic findings and disability in rheumatoid arthritis]

OBJECTIVE

To evaluate if the duration of disease influences the link between different radiographic specific features and disability in rheumatoid arthritis (RA) and the influence of disease duration on this relationship.

METHODS

Conventional X- rays of both hands of 96 patients with RA were evaluated independently by 2 readers using Kayes' modification of the Sharp method. Disability was evaluated with the Spanish version of the HAQ questionnaire.

RESULTS

The mean HAQ was 1, 39 ± 0, 79. The mean total radiographic score was 0.8 (18% of the maximum possible score). Total and joint space narrowing scores only displayed a statistically significant correlation (r=0.33, r=.37, respectively, P<.05) with disability in the late RA group (>7 years). Erosion and malalignment scores were not correlated with HAQ. There was a statistically significant correlation between the eating, dressing and reach HAQ-categories and the total radiographic score in the late RA group (r=0.48, P<.001, r=0.42, P<.01, r=0.3, P<.05, respectively).

CONCLUSION

This work suggests that HAQ disability and radiographic damage are only related in cases with late RA. In this group, the subtotal radiographic score most related with disability is the joint space narrowing score.

Measurement of periarticular bone mineral density in the hands of patients with early inflammatory arthritis using dual energy x-ray absorptiometry

Hand bone densitometry is more sensitive than standard radiology in the measurement of disease-related bone damage in early arthritis. Most studies employing dual energy x-ray absorptiometry (DXA) have evaluated the whole hand. The aim of this study was to evaluate a method that quantified bone density in regions of interest that were confined to the juxta-articular areas of metacarpo-phalangeal (MCP) and proximal interphalangeal (PIP) joints. Patients with inflammatory arthritis affecting the hands were selected for study. Postero-anterior (PA) scans of selected juxta-articular sub-regions were acquired using a Hologic 4500 Elite bone densitometer and forearm software. Each hand was scanned three times in immediate succession with repositioning between scans. The six selected sub-regions included the periarticular regions of the second, third, and fourth MCP and PIP joints. Sub-regions of different dimensions (4 and 5 mm proximal and distal to the joint space) were assessed at each joint. Coefficients of variation (CV) were calculated for bone mineral density (BMD) and bone mineral content (BMC) of each selected sub-region. Eighty four individual hand joints in seven patients were evaluated three times. Precision values ranged between 0.89% and 2.37% for BMD and between 1.38 and 3.26 for BMC measurements. BMD measurements of MCP joints were more precise than PIP joints. BMD measurements of 10-mm sub-regions were more precise than 8-mm sub-regions. The precision value for the net average BMD measurement of the six sub-regions evaluated was 0.78% for 8-mm sub-regions and 0.73% for 10-mm sub-regions. Net average BMC measurements had CV values of 1.11% and 1.08%, respectively. DXA can be used to reliably measure periarticular BMD and BMC of small joints in the hands in patients with early inflammatory arthritis. Precision values for quantifying juxta-articular bone approximated BMD measurements of the spine.

Reproducibility of metacarpophalangeal bone mass measurements obtained by dual-energy X-ray absorptiometry in healthy volunteers and patients with early arthritis

The prognostic value of measuring hand bone mineral density (BMD) in patients with early arthritis (EA) has been recently assessed. In this work, we evaluate the reproducibility of measuring juxta-articular BMD by dual-energy X-ray absorptiometry (DXA) at the second to fifth metacarpophalangeal (MCP) joints. We obtained whole hand (WH) and MCP joint BMD measurements from 16 healthy subjects and from 22 patients with EA. The coefficient of variation, intraclass correlation coefficient (ICC), and smallest detectable difference (SDD) were calculated. The coefficient of variation ranged from 1.3% to 0.7% at MCP joints and from 1.4% to 0.9% in the WH measurements, respectively. The intra- and interobserver ICC for both WH and MCP joints ranged from 0.97 to 0.99. The SDD at the different anatomical locations analyzed ranged from 0.006 to 0.022 g/cm2 in healthy controls and from 0.005 to 0.010 g/cm2 in EA. Interestingly, patients who fulfilled rheumatoid arthritis criteria showed a lower bone mass than those with undifferentiated arthritis. Therefore, BMD measurements obtained by DXA at MCP joints were reproducible and it might be useful in the study of patients with EA.

Efficacy and safety of iguratimod compared with placebo and salazosulfapyridine in active rheumatoid arthritis: a controlled, multicenter, double-blind, parallel-group study

We conducted a 28-week, randomized, double-blind, parallel-group study of iguratimod in 376 Japanese patients with active rheumatoid arthritis to compare the efficacy and safety of the drug with those of placebo and salazosulfapyridine. In the American College of Rheumatology (ACR) 20 response rate, iguratimod was superior to placebo (53.8% versus 17.2%; Fisher's exact test, P < 0.001) and was not inferior to salazosulfapyridine (63.1% versus 57.7%, 95% confidence interval for the rate difference, -7.9% to 18.7%). Iguratimod began exhibiting its therapeutic effect within 8 weeks after the initiation of treatment and was effective even in patients who had a poor response to previous treatment with disease-modifying antirheumatic drugs. No statistically significant difference was noted in the incidence of adverse reactions between iguratimod and salazosulfapyridine. The study results suggest that iguratimod could become a new option for the treatment of rheumatoid arthritis.

The Definition and Measurement of Disease Modification in Inflammatory Rheumatic Diseases

This article focuses on measures that are used to evaluate disease activity, damage, and function in three major inflammatory musculoskeletal disorders. The instruments used in rheumatoid arthritis, where most of the methodologic work has been done, are extensively discussed and instruments for the respective domains in psoriatic arthritis and ankylosing spondylitis are likewise presented.

Asymmetry of small joint involvement in rheumatoid arthritis: prevalence and tendency towards symmetry over time

OBJECTIVES

To quantify asymmetry of radiological joint damage in rheumatoid arthritis (RA), to determine whether asymmetrical damage to joints in RA becomes symmetrical over time, and to identify factors predictive of symmetrization.

METHODS

In phase 1, initial, mid-term (mean follow-up: 3 years) and late (mean follow-up: 8 years) radiographs of 48 patients with definite RA (English population) were graded by the Modified Larsen (ML) system. In phase 2, 27 subjects (Canadian population) with at least one asymmetrical pair of joints in the hands or feet were identified. Two successive radiographs of 77 asymmetrical joints, separated by at least 2 years, were compared. Clinical and biological factors were assessed for their ability to predict symmetrization, defined as a reduction in side-to-side difference over time of two or more ML grades.

RESULTS

In phase 1, the overall rate of asymmetry was 12.9% (95% CI: 11.2-14.5%), increasing from 9.7% (first visit) to 13.8% (mid-term) and 14.4% (last visit). Metacarpophalangeal (MCP) joints were more frequently asymmetrical than thumb (MCP and interphalangeal) joints (P = 0.0064) and proximal interphalangeal (PIP) joints (P < 0.0001); wrist quadrants were more frequently asymmetrical than PIP joints (P < 0.0001). In phase 2, two groups were identified and compared: symmetrizers (22 joints) and non-symmetrizers (55 joints). The overall probability of small joints in the hand and foot symmetrizing was 28.5%. Rheumatoid factor (RF) was predictive of symmetrization. The risk of symmetrization was significantly increased in RF-positive patients with asymmetric joints (P = 0.01). The prevalence of asymmetry did not decrease with disease duration, despite symmetrization.

CONCLUSIONS

Prevalence of asymmetry in joint damage in RA was 13-16%. Symmetry was more evident in PIP joints than in MCP and wrist joints. Seropositive patients are more than twice as likely to symmetrize than seronegative patients. Data regarding the tendency for symmetrization may have value in the clinical management of RA patients with asymmetrical joint damage.

The Sharp/van der Heijde method out-performed the Larsen/Scott method on the individual patient level in assessing radiographs in early rheumatoid arthritis

OBJECTIVE

To test the reliability of two radiologic scoring methods in rheumatoid arthritis (RA)--the Sharp/van der Heijde (SvH) and the Larsen/Scott (LS)--with generalizability analyses.

STUDY DESIGN AND SETTING

Films of 51 patients representing the spectrum of early RA were read by two raters for each method. The discriminative ability and responsiveness were expressed as: intraclass correlation coefficients (ICCs), two types of smallest detectable difference (SDD), and two types of smallest detectable change (SDC); reflecting measurement error when discriminating between or detecting changes within (1) individuals or (2) groups. They were calculated for (average) scores of one to three raters.

RESULTS

The discriminative capacity (0.85-0.97) and responsiveness (0.91-0.97) were good when expressed by ICC. On the group level the SDDs and SDCs ranged between 0.6-3.3% of the max. obtainable score. On the individual level, the scores showed better reliability measured with the SvH (SDDs 2.0-3.4%) than with the LS (SDDs 5.3-9.2%). The SvH also assessed changes in scores in individuals with less measurement error (SDCs 1.3-2.2%) than the LS (SDCs 2.3-3.9%).

CONCLUSION

For early RA patients, the SvH seems preferable if analyses on individual level are included.

Diagnostic value of radiographs of the hands and feet in early rheumatoid arthritis

The extent to which radiographs of the hands and feet can contribute to the diagnosis of early rheumatoid arthritis (RA) has received little research attention. Yet, the workup for recent-onset inflammatory joint disease usually includes radiographs of the hands and feet. We reviewed the literature for data on the value of these radiographs for diagnosing early RA. We sought to determine whether radiographic changes in the hands and feet constitute a valid diagnostic criterion, i.e., show good discrimination, good reproducibility, and an ability to detect early disease. Furthermore, we evaluated whether the sensitivity, specificity, and positive and negative predictive values of these changes could be calculated from published data. Few cohort studies of early inflammatory joint disease have been published, and the data come mainly from studies in early RA. Among radiographic alterations described to date, erosions seem associated with the best reliability and discriminating power. Radiographic alterations are of limited sensitivity for early rheumatoid arthritis because they occur only after some time. Radiographs of the hands and feet are far easier to obtain than magnetic resonance imaging and ultrasonography, which seem promising but are still undergoing validation.

Prevention or retardation of joint damage in rheumatoid arthritis: issues of definition, evaluation and interpretation of plain radiographs

This article discusses methodological concepts and challenges underlying the interpretation of changes in plain radiographs of the joints of patients with rheumatoid arthritis. A series of consensus conferences (OMERACT [Outcome Measures in Rheumatology]) has resulted in the formulation and execution of a research agenda to harmonise reading and interpretation of films. This is important in the light of the increasing evidence that drugs can impact on the progression of joint damage. In these conferences, methodological issues have been divided according to applicability tenets summarised in the OMERACT Filter of Truth, Discrimination, and Feasibility. To pass the Filter, a measure must measure what it is supposed to measure (Truth), must discriminate between clinically relevant states (Discrimination) and be feasible in terms of costs and interpretability. 'Truth' issues include the choice of joints, the view and other technical specifications of the radiograph, such as which abnormalities to score, the level of aggregation of the information, culminating in the choice of the scoring system. 'Discrimination' issues include reproducibility and sensitivity to change. The current research agenda includes items such as defining a criterion for 'no relevant progression', comparison between time ordered and randomly ordered reading, further comparison of methods and subscores, and methodology around missing values.

Radiographic outcome after three years of patients with early erosive rheumatoid arthritis treated with intramuscular methotrexate or parenteral gold. Extension of a one-year double-blind study in 174 patients

OBJECTIVE

To compare the radiographic outcomes after 36 months in patients with early erosive rheumatoid arthritis (RA) who were treated with methotrexate (MTX) or gold sodium thiomalate (GSTM).

METHODS

In a randomized, double-blind fashion, 174 patients from two centres were assigned to receive weekly intramuscular injections of either 15 mg MTX or 50 mg GSTM. After 12 months, the study was continued as an open prospective study for an additional 2 yr, administering the same amount of MTX and half of the GSTM dose. Radiographic outcomes were assessed by standardized methods in all patients at baseline and after 6, 12, 24 and 36 months.

RESULTS

Intention-to-treat analysis showed that patients treated with MTX had higher radiographic scores and more erosive joints at all follow-up points. However, there was no statistically significant difference between the two treatment groups. The progression rate was significantly slower during the second and third years of follow-up in both groups. Baseline and time-integrated (area under the curve over 6 months) disease activity parameters were good predictors of radiographic outcome after 3 yr. Seropositivity was not an independent predictor of progression. However, patients who were positive for rheumatoid factor had higher time-integrated disease activity (with less response to treatment) and thus their disease was significantly more progressive.

CONCLUSION

Both of the disease-modifying compounds used in this study, MTX and GSTM, were able to reduce the slope of radiographic progression during 3 yr of follow-up. There was some advantage for parenteral gold but no significant intergroup difference.

Modified sharp method: factors influencing reproducibility and variability

BACKGROUND AND OBJECTIVES

In rheumatoid arthritis, joint radiography is still the most frequently used instrument to assess the progression of joint damage. Unfortunately, the poor quality of the radiographic scoring methods available has a negative impact on the power in clinical trials. This study focuses on the influence of the following 4 factors on radiographic scores according to van der Heijde's modification of the Sharp method: intraobserver variation, interobserver variation, follow-up time, and number of measurement occasions within a patient series.

METHODS

One hundred and seventy-two patients in the early stages of rheumatoid arthritis were followed up. During the first 3 years, radiographs of the hands and feet were taken twice yearly and scored by 3 observers. The scoring process was repeated after an additional 3-year period. Correlation coefficients and differences between observers were calculated to define variability. The influence of the 4 factors on variability was studied.

RESULTS

One observer assigned a significantly higher score than the other 2, who had been trained together. Interobserver variability decreased as follow-up time increased. Interobserver correlation coefficients became higher, with smaller differences between observers for progression scores than for absolute scores. Increasing the number of measurements within a patient series led to higher scores. Intraobserver correlation coefficients were high, and a training effect occurred when the time between measurements was 1 year, resulting in lower scores.

CONCLUSIONS

This study demonstrates that, and shows how, the investigated factors influence the variability of the modified Sharp method. It is extremely important to take interobserver variation into account when designing protocols for multicenter clinical trials. A progression scoring method is recommended for studies assessing radiographic damage or clinical trials.

Rheumatoid arthritis in African Colombians from Quibdo

OBJECTIVES

Little data is available on the prevalence and incidence of rheumatoid arthritis (RA) or the genetic and environmental factors that influence RA risk and severity in non-Caucasian populations. The prevalence of RA in Caucasians and some Native American populations is 1% or more; in contrast, low prevalences of RA have been reported in some African populations. We determined the hospital incidence (HI) and period prevalence (PP) of RA in African Colombians in Quibdo, Colombia, by using data collected at the Hospital San Francisco de Asis, a primary-to-tertiary care center. Genetic and immunologic studies of factors that influence RA risk and severity, such as HLA genes, immunoglobulin-A (IgA) rheumatoid factor (RF), and antikeratin antibodies (AKA) were performed. African Colombians with RA also were compared with Mestizo RA patients from Medellín, Colombia.

METHODS

To determine the HI, all the outpatient charts for 1995 were reviewed (n = 3,044). PP during 1996 (Jan-Dec) was assessed by stratified sampling of all African Colombians aged 18 or more having arthralgia. Participants completed a survey and a pretested standard questionnaire, had hands and feet X-rays, and provided a blood sample. Total and IgA RF were measured by turbidimetry and ELISA, respectively; AKA were assessed by indirect immunofluorescence on rat esophagus. HLA-DRB1 and DQB1 alleles were determined by polymerase chain reaction technique with primers of specific sequence and by reverse dot blot.

RESULTS

The HI was 0.65 cases per 1,000 person years. There were 321 individuals with arthralgia (0.3%; 95% CI, 0.28-0.3), 18 of whom fulfilled the American College of Rheumatology criteria for RA (PP in the general population, 0.01%; 95% CI, 0.008-0.02). Lower erosion scores were seen in African Colombian patients compared to Mestizos (n = 56), although duration of disease was similar in each group. No association between any HLA allele and RA risk or RA severity or between autoantibodies and RA severity was observed in African Colombians. Comparisons showed no significant differences between African Colombians and Mestizo patients in the presence of RF (total and IgA), AKA, age at onset, extra-articular manifestations, formal education level, and history of malaria.

CONCLUSIONS

These results suggest that RA in African Colombian patients from Quibdo is rare, may be less severe in terms of radiographic damage than in Colombian Mestizo patients, and lacks association to HLA-DRB1 and DQB1 alleles. Additionally, RF (total and IgA) and AKA are not markers of progression and activity of the disease in this population.

Assessment of phalangeal bone loss in patients with rheumatoid arthritis by quantitative ultrasound

OBJECTIVE

Periarticular osteopenia is an early radiological sign of rheumatoid arthritis (RA). Quantitative ultrasound (QUS) devices have recently been shown to be useful for assessing osteoporosis. In this study the capability of a transportable and easy to use QUS device to detect skeletal impairment of the finger phalanges in patients with RA was investigated.

METHODS

In a cross sectional study 83 women (30 controls, 29 with glucocorticosteroid (GC) treated RA, and 24 with GC treated vasculitis) were examined. QUS measurements were obtained at the metaphyses of the proximal phalanges II-V and directly at the proximal interphalangeal joints II-IV with a DBM Sonic 1200 (IGEA, Italy) QUS device. Amplitude dependent speed of sound (AD-SoS) was evaluated. In 23 of the patients with RA, hand radiographs were evaluated.

RESULTS

Significant differences between patients with RA and the other groups were found for AD-SoS at both measurement sites. Compared with age matched controls, the AD-SoS of patients with RA was lowered by two and three standard deviations at the metaphysis and joint, respectively. Fingers of patients with RA without erosions (Larsen score 0-I) already had significantly decreased QUS values, which deteriorated further with the development of erosions (Larsen II-V).

CONCLUSION

This study indicates that QUS is sensitive to phalangeal periarticular bone loss in RA. QUS is a quick, simple, and inexpensive method free of ionising radiation that appears to be suited to detection of early stages of periarticular bone loss. Its clinical use in the assessment of early RA should be further evaluated in prospective studies.

Radiographic signs of bone destruction in the arthritic temporomandibular joint with special reference to markers of disease activity. A longitudinal study

OBJECTIVE

To investigate the progression of radiographic changes of the temporomandibular joint (TMJ) with reference to plasma levels of interleukin-1beta (IL-1beta), C-reactive protein (CRP) and disease duration.

METHODS

Twenty-one patients with chronic inflammatory joint disease and TMJ involvement were included. Individualized tomography of the TMJ was performed twice with an interval of at least 12 months. Blood samples were analysed for IL-1beta and CRP.

RESULTS

Significant progression of the overall grade of radiographic changes occurred during the observation period, whereas erosions showed great interindividual variability. Progression of TMJ bone loss was correlated to raised levels of CRP and, in patients with a diagnosis of rheumatoid arthritis, or with shorter duration, also to plasma IL-1beta.

CONCLUSION

Progression of overall grade of radiographic changes in the TMJ occurs in patients with chronic inflammatory joint disease. Raised levels of serum CRP are associated with progression of TMJ bone loss.

Relationship between bone mineral density and radiologic scores of hands in rheumatoid arthritis

This study proposed to assess the relationship between hand bone mineral density (BMD) and radiographic scoring methods, important measures to assess the course of rheumatoid arthritis. Hand, spine, and femur BMD of 49 patients with rheumatoid arthritis and 34 age- and sex-matched healthy control subjects were measured using dual X-ray absorptiometry and the results were compared. Standard hand films of patients were scored according to five different scoring methods--Larsen method, modified Larsen method, Sharp/van der Heijde modified method, carpo:metacarpal ratio, and simple erosion narrowing score (SENS)--and were correlated with hand BMD. There was a moderate relationship between hand BMD measurements and radiologic scores. SENS was the method that correlated significantly with the highest correlation coefficient. Hand BMD correlated significantly with disease duration and c-reactive protein levels. Hand BMD in patients with rheumatoid arthritis was significantly lower than in control subjects, whereas there was no significant difference in axial BMD measurements. The advantages and disadvantages of hand BMD and radiographic scoring methods were determined. Our results indicate that hand BMD measurements may be as useful is assessing the course of rheumatoid arthritis as radiologic scoring methods. However to prove this, a well-designed reference population for hand BMD and longitudinal studies are required.

Radiographic assessment of hip osteoarthritis progression: impact of reading procedures for longitudinal studies

OBJECTIVE

To compare radiographic reading procedures and evaluate their impact on sample size in hip osteoarthritis (OA) longitudinal studies.

METHODS

Pelvic radiographs performed twice, three years apart, in 104 patients with hip OA were read by a single reader using the Kellgren and Lawrence system, joint space narrowing scale, and joint space width (JSW). Reading procedures were (a) films read as single radiographs, (b) films grouped by patient but read in random order, (c) films grouped by patient and chronologically ordered, all with landmarks for JSW measurements, (d) films read as single radiographs, without landmarks for JSW measurements. JSW was measured at the narrowest point with a 0.1 mm graduated magnifying glass.

RESULTS

More Kellgren and Lawrence or joint space narrowing grades were modified respectively with the single (42% and 37%) than with the paired (32% and 23%) or chronologically ordered (34% and 29%) reading procedures. Variability of JSW progression was principally related to mean progression (88.3%) and landmarks (almost 10%). Standardised response means were -0.71 with the paired reading procedure with landmarks, -0.68 with the single reading procedure with landmarks, -0.65 with the single reading procedure without landmarks. With landmarks, 10% more patients would be needed using single than paired reading. Using single reading, 10% more patients would be needed without landmarks than with landmarks.

CONCLUSION

Kellgren and Lawrence grading seems to be influenced by the reading procedure, as is joint space narrowing grading, for assessing hip OA. Paired reading procedure with landmarks for JSW should be recommended in longitudinal studies.

Reading radiographs in chronological order, in pairs or as single films has important implications for the discriminative power of rheumatoid arthritis clinical trials

OBJECTIVE

To determine the influence of reading series of films in chronological order, in pairs with unknown time sequence, or as single films, on precision and sensitivity to change.

METHODS

Two studies were performed with 10 and 12 patients fulfilling the American College of Rheumatology criteria. In Study 1, two sets of films with a 1 yr interval were scored in chronological order, in pairs, and as single films. In Study 2, four sets of films, with a 1 yr interval each, were scored in chronological order, as single films and as single-pair (right and left together). All films were scored with the Sharp/van der Heijde method by two independent observers. Data were analysed with a repeated measures ANOVA using a full mixed effects model. Two generalizability (G) coefficients were constructed for reliability and for change.

RESULTS

Study 1: the interobserver reliability was similar for the three methods (G(reliability) chronological 0.94, paired 0.88, single 0.93); progression was a mean increase (averaged over patients, observers and methods) from 26 to 37 (P=0.046). The sensitivity for change was greater for the chronological than for the paired and single scoring (G(change) 0.39, 0.22 and 0.24, respectively). Study 2: the interobserver reliability was 0.86 for chronological, 0.76 for single-pair and 0.91 for single readings. Significantly more progression was measured with the chronological compared with the single-paired and single methods (15.9 vs 8.5 and 8.3; P=0.0001). A constant progression was suggested by chronological reading, in contrast to a stabilization in the other two methods after 1 yr.

CONCLUSION

Reading films in chronological order is most sensitive to change in a time period up to 3 yr follow-up; this was already present after 1 yr, but even more pronounced with longer follow-up.

Reliability and sensitivity to change of a simplification of the Sharp/van der Heijde radiological assessment in rheumatoid arthritis

OBJECTIVE

To determine the reliability and sensitivity to change of a simplified radiological scoring method [simple erosion narrowing score (SENS)] for rheumatoid arthritis (RA). SENS was compared to the Sharp/van der Heijde score (SHS) as a gold standard.

METHODS

Sets of seven radiographs of hands and feet were taken of 20 RA patients with a wide spectrum of radiological damage. For 14 patients, these seven radiographs were taken during a follow-up period of 5 yr, and for six patients during a follow-up of 10 yr. Each set of radiographs was scored twice by the same observer (DvdH). Erosions and joint space narrowing were scored with SHS (range 0-448) in 32 and 30 joints in the hands, respectively, and both in 12 joints in the feet. SENS gives a score of 1 if there is any erosion in a joint and also 1 if there is any narrowing in the joint (range 0-86). In each case, SENS was derived from SHS. To analyse data, generalizability theory and repeated measurements ANOVA were used.

RESULTS

The overall reliability coefficient was 0.81 for SHS and 0.80 for SENS. Intra-observer reliability [intraclass correlation coefficient (ICC)] was 0.99 and 0.98 for SHS and SENS, respectively. The ICC for the sensitivity to change was 0.84 for SHS and 0.88 for SENS. The smallest detectable difference (SDD) could be determined for both methods. The presence of progression based on this SDD was very comparable between the two methods.

CONCLUSION

The measurement properties of SENS are good and comparable to SHS. This makes SENS suitable for use in clinical practice and in large (epidemiological) studies, especially in the first years of disease.

Assessment of rheumatoid arthritis using a modified scoring method on digitized and original radiographs

OBJECTIVE

The results of different readers' interpretations of laser-digitized hand radiographs versus original radiographs were compared to determine the reproducibility of scoring of erosions (ERO), joint space narrowing (JSN), and their combination (ERO + JSN) in patients with rheumatoid arthritis (RA).

METHODS

Standardized radiographs of both hands were obtained at 2 visits (baseline and 6-24-month followup) from 30 patients with established RA. Conventional and laser-digitized (pixel sizes 50 microm and 100 microm) radiographs were scored independently by 3 experienced and trained radiologists who were blinded to the order of the visits. Scoring of radiographs was based on the validated Genant grading system.

RESULTS

Intertechnique (intrareader) correlation coefficients at baseline were 0.90-0.93 for scoring of ERO, 0.90-0.94 for scoring of JSN, and 0.92-0.95 for ERO + JSN; for scoring of progression between baseline and followup, these values were 0.93-0.97, 0.87-0.95, and 0.93-0.97, respectively. Interreader (intratechnique) correlation coefficients at baseline were 0.82-0.96 for scoring of ERO, 0.69-0.91 for scoring of JSN, and 0.80-0.95 for ERO + JSN; for scoring of progression between baseline and followup, these values were 0.90-0.97, 0.80-0.92, and 0.90-0.95, respectively. Intrareader (intratechnique) correlation coefficients were 0.90-0.97 for scoring of the original radiographs and 0.90-0.98 for scoring of the digitized images at 100 microm.

CONCLUSION

Using this modified grading system, scoring of RA progression directly from paired, high-resolution monitors of laser-digitized images of the hands provided highly reproducible results, comparable to those obtained from the original radiographs. Thus, this method may have useful applications in clinical trials involving RA.

Radiographic progression in rheumatoid arthritis: a long-term prospective study of 109 patients

OBJECTIVE

To investigate the long-term radiographic course as a mathematical function of disease duration in individual patients and in a group of patients with rheumatoid arthritis (RA).

METHODS

In 109 patients with RA, radiographic examinations of 46 diarthrodial joints were performed at regular intervals of 1-3 years, for up to 30 years after disease onset.

RESULTS

Five main types of progression were identified: 1) a rare type (<1%), with no radiographic progression at all; 2) a type with a slow or moderate onset, but an increasing progression rate (9% exponential growth type and 30% linear type); 3) a type with a moderate-to-fast onset and a stable progression rate (the square-root type; 11%); 4) a type with a fast onset, but a later decreasing progression rate (the first-order kinetics type, 30%); and 5) a type characterized by slow onset, then acceleration and later deceleration (the sigmoid type, 20%).

CONCLUSION

The progression of radiographic damage in RA followed mathematical functions of time. The identification of progression type may be used in the prediction of outcome in patients with RA.

Rheumatoid arthritis: follow-up and response to treatment

OBJECTIVE

To assess the role of diagnostic imaging techniques in the identification and follow-up of the anatomical damage induced by the chronic inflammatory process of rheumatoid arthritis (RA) not only to study the natural history of the disease but also and especially to assess the long-term response to disease-modifying anti-rheumatic drugs (DMARD).

MATERIALS AND METHODS

The relative literature data were reviewed and compared with our personal experience with different imaging modalities such as conventional radiography (CR), ultrasound (US) and magnetic resonance imaging (MRI).

RESULTS

Several radiologic techniques have been used over the years to study articular damage in RA: they describe and quantify the articular damage (semi-quantitative analysis) based on a series of parameters and elementary anatomical lesions which are given a rising score. For its sensitivity in detecting early disease signs and the possibility to express anatomical damage progression quantitatively, Sharp's index is considered the best tool for evaluating RA patients. The close correlation between clinical parameters and the radiologic scores obtained regardless of the method applied led to a new concept of anatomical damage related to the 'radiologic progression of the disease' which is a more precise measure of RA severity than the single isolated radiograph. The progression of radiologic damage in rheumatoid arthritis is expressed as the number or proportion of new eroded joints/year: independent of the index adopted and the terms used to express progression, severe radiologic damage occurs in the early disease stage, involving approximately 2% of the joints within about 1 year, and 13% within 2 years, with an estimated average annual progression of 1.3%. Radiologic techniques evaluate the anatomical damage in the course of RA only with reference to the osseous component of the joint and therefore apply to a disease stage that is largely irreversible. MRI and US detect the soft-tissue damage occurring in the earlier phases and are more likely to respond to early treatment. The former technique appears to be useful to detect soft-tissue damage like synovial pannus, intra- and periarticular and peritendinous effusion, capsuloligamentous articular and tendon changes. Its high sensitivity for minimal bone erosions and chondromalacia has been demonstrated. US allows to demonstrate a wide range of soft-tissue changes of the hand and wrist. Joint-cavity widening, loss of cartilage definition, bone erosions, widening of flexor tendon sheath and tendon structure are also well depicted on ultrasound images.

CONCLUSIONS

CR is the central tool in the diagnosis, staging and follow-up of RA patients and in general in the assessment of treatment efficacy; MRI and US are complementary tools.

Predictive factors in rheumatoid arthritis

Rheumatoid arthritis (RA), a chronic polyarticular disease affecting about 1% of the adult population of the world, produces significant joint destruction, physical impairment, work disability, and early mortality. Patients with RA may have a slowly or rapidly progressive disease or a self-limited one. To design a rational treatment program for all patients, the clinician must identify early on whether patients are destined to have a rapidly progressive disease. This article reviews socioeconomic, psychological, immunogenetic, and disease-related features that may help to identify such patients.

Clinical trials in rheumatoid arthritis: methodological suggestions for assessing radiographs arising from the GRISAR Study. Gruppo Reumatologi Italiani Studio Artrite Reumatoide

OBJECTIVES

The three x ray assessors of the GRISAR study (blinded to treatment) gave consensual erosion and damage scores to the baseline and 12 month radiographs of 284 rheumatoid arthritis (RA) patients using three different methods: single readings (blinded as to patient and chronological sequence of the x rays), paired readings (blinded as to sequence), and chronologically ordered paired readings. The aim was to evaluate which of these reading procedures is the most appropriate for clinical trials.

METHODS

The progression of the scores obtained using each procedure was compared by means of descriptive statistics, principal components analysis, and intra-patient correlation coefficients of pairs of methods. Bootstrap estimates of the variance of the difference in the means of two equally sized random samples were calculated to evaluate the power of the statistical analysis performed to assess the possible treatment effect for both paired and chronological reading methods.

RESULTS

(a) The standard deviations of the paired and chronological readings were similar, but that of the single readings was higher. (b) The knowledge that two x rays were of the same patient accounted for a sizeable proportion of the between method variability. (c) Agreement was satisfactory between the paired and chronological methods for both scores but, between them and the single readings, it was modest for erosions and poor for damage. (d) The bootstrap estimate of the variance of the difference was smaller for the paired than the chronological method, possibly giving it greater power to test treatment effect.

CONCLUSIONS

These results suggested that paired readings were the most suitable for evaluating the progression of joint damage in the GRISAR study.

Plain X-rays in rheumatoid arthritis: overview of scoring methods, their reliability and applicability

Radiographs are a suitable outcome measure in patients with rheumatoid arthritis. They reflect the history of the joint pathology and provide a permanent record necessary for serial evaluation of the disease. Great care should be taken to overcome technical problems with radiographs to ensure that good quality films are available to score. Many scoring methods have been described ranging from a global score for the whole patient to the more sophisticated methods of scoring erosions and joint space narrowing in a selected number of joints. These latter abnormalities give additive information and are the most important features in scoring radiographs in rheumatoid arthritis. An overview of the most important methods is given with an emphasis on four selected methods: the Larsen method, a modification of this by Rau and Herborn, the Sharp method and a modification of this by van der Heijde. All four methods produce sufficient intra- and inter-observer reliability. Although data are scarce, the Sharp method and its modifications seem the most sensitive methods for detecting changes over time. However, these are more time-consuming than the Larsen method or its modifications. Depending on the type of study a choice can be made between the two types of methods. For clinical trials where small differences are important, the (modified) Sharp method seems the most appropriate. In working with large data sets, time might be a more crucial factor and, therefore, the (modified) Larsen method could be chosen.

Treatment of secondary progressive multiple sclerosis with the immunomodulator linomide: a double-blind, placebo-controlled pilot study with monthly magnetic resonance imaging evaluation

Linomide (quinoline-3-carboxamide) is a synthetic immunomodulator that increases the natural killer cell activity. We previously demonstrated that linomide effectively inhibited the clinical and histopathologic signs of acute and chronic relapsing experimental autoimmune encephalomyelitis. We report a double-blind, placebo-controlled study to evaluate tolerability and to obtain preliminary indications of the clinical efficacy of linomide on secondary progressive MS. Thirty patients suffering from clinically definite and laboratory-supported secondary progressive MS, with an expanded disability status scale (EDSS) of 3.0 to 7.0, were included in this study. Patients were treated daily with linomide (2.5 mg) or placebo orally and were followed up for side effects and changes in their neurologic status; monthly MRI scans were taken throughout the treatment period. Twenty-four patients completed at least 6 months of treatment. Mild to moderate side effects, including muscle pains, arthralgia, and edema, were present in 11 of the 15 patients receiving placebo and in 13 of the 15 patients treated with linomide. At 24 weeks, the mean shift in EDSS was +0.272 +/- 0.156 in the placebo group versus -0.166 +/- 0.167 in the linomide group (p = 0.0451). The percentage of patients with evidence of "activity" on their MRI (new, enlarging, or new gadolinium diethylenetriaminepentaacetic acid [Gd-DTPA]-enhancing lesions) throughout the treatment period was 75% in the placebo group and 33% in the linomide group (p = 0.0205). The mean total number of new Gd-DTPA-enhancing lesions per MRI scan for the same period was 0.42 +/- 0.143 in the placebo group and 0.19 +/- 0.114 in the linomide group (p = 0.0387). In this study, linomide proved to be safe and well tolerated in patients with secondary progressive MS. In addition, our results indicate that linomide tends to inhibit the progression of the disease, especially preventing the appearance of new active lesions in the MRI scans. Based on these results, two multicenter phase III trials are currently under way in the United States and in Europe and Australia.

Healing phenomena of erosive changes in rheumatoid arthritis patients undergoing disease-modifying antirheumatic drug therapy

OBJECTIVE

To describe radiographic healing phenomena and reparative changes of joint destruction in rheumatoid arthritis (RA).

METHODS

Serial radiographs of 6 patients with erosive RA undergoing long-term treatment with disease-modifying antirheumatic drugs (DMARDs) were studied. Radiographs showing healing phenomena were reproduced, and examples of single joints are shown.

RESULTS

The examples show recortication of erosions, filling in of erosions with new bone, and secondary osteoarthrosis with bone sclerosis and osteophyte formation. Commonly use radiographic scoring methods do not have the capacity to account for these reparative changes.

CONCLUSION

Healing phenomena can be observed in RA patients undergoing long-term DMARD treatment. These phenomena can be regarded as clinical end points, and their assessment should be incorporated into existing standardized methods for radiologic evaluation and scoring of RA.

Development and validation of the European League Against Rheumatism response criteria for rheumatoid arthritis. Comparison with the preliminary American College of Rheumatology and the World Health Organization/International League Against Rheumatism Criteria

OBJECTIVE

To validate the European League Against Rheumatism (EULAR), the American College of Rheumatology (ACR), and the World Health Organization (WHO)/International League Against Rheumatism (ILAR) response criteria for rheumatoid arthritis (RA).

METHODS

EULAR response criteria were developed combining change from baseline and level of disease activity attained during follow up. In a trial comparing hydroxychloroquine and sulfasalazine, we studied construct (radiographic progression), criterion (functional capacity), and discriminant validity.

RESULTS

EULAR response criteria had good construct, criterion, and discriminant validity, ACR and WHO/ILAR criteria showed only good criterion validity.

CONCLUSION

EULAR response criteria showed better construct and discriminant validity than did the ACR and the WHO/ILAR response criteria for RA.

Measurement of hand bone mineral content by dual energy x-ray absorptiometry: development of the method, and its application in normal volunteers and in patients with rheumatoid arthritis

OBJECTIVES--To develop a method of measuring hand bone mineral content (BMC) by dual energy x ray absorptiometry (DXA); to apply this method of measuring hand BMC to normal volunteers to ascertain causes of variability; and to measure hand BMC in patients with rheumatoid arthritis (RA) of varying duration and severity. METHODS--The x ray beam of the Hologic QDR 1000 dual energy x ray absorptiometer was hardened by introducing a perspex-aluminium plate and the analysis software altered to allow for the small tissue bulk of the hand compared with the torso. Ninety five volunteers (46 men age 24-81 and 49 women age 20-83) had scans of both hands. Eight volunteers were assessed repeatedly to establish reproducibility and effect of hand position. Fifty six patients (22 men, 34 women, age range 25-86 years) with RA of differing duration and severity, had hand BMC measurement by DXA. RESULTS--The precision of BMC measurement was 2.3% with no additional variation due to hand position. Hand dominance had no significant effect on BMC. In men, hand BMC correlated with height (r = 0.57, p < 0.0001), weight (r = 0.58, p < 0.0001), forearm span (r = 0.5, p = 0.0006) and hand volume (r = 0.66, p < 0.0001). In women hand BMC correlated with height (r = 0.66, p < 0.0001), weight (r = 0.4, p = 0.003), forearm span (r = 0.3, p = 0.03) and hand volume (r = 0.49, p = 0.0008). After correcting for all these variables, male volunteers had significantly higher hand BMC than female volunteers (p = 0.01) and patients with RA had lower hand BMC than normal volunteers (total hand BMC in male volunteers 90.9 gms, 95% CI 86.9-95, in male patients 81.7 gms, 95% CI 73.7-89.6, p < 0.004, total hand BMC in female volunteers 62.2 gms 95% CI 59.8-64.5, female patients 52.3 gms, 95% CI 48.1-56.5, p < 0.005). In patients with RA, the hand BMC showed an inverse correlation with age (r = -0.44, p = 0.01), disease duration (r = -0.62, p = 0.0003), Larsen's grades (r = -0.62, p = 0.0002) and modified Sharp's method score (r = -0.69, p < 0.0001) in female patients only. CONCLUSIONS--A new, sensitive and reproducible technique of measurement of hand bone mineral content by DXA, has been developed and this method has been applied to normal volunteers and patients with RA. Hand dominance had no significant effect on hand BMC. After correcting for physical size, men have higher hand BMC than women. Hand BMC inversely correlates in women patients with disease duration and other validated methods of assessing radiological outcome in RA. Longitudinal studies are needed to establish its role in monitoring disease progression.