O. L. Meyers

Clinical assessment of disease activity in rheumatoid arthritis: evaluation of a functional test

A cross sectional analysis of the correlation between clinical, laboratory, and radiological markers of disease activity in 98 patients with classical rheumatoid arthritis (RA) is reported. The median age was 38 years, the median age at onset of disease 29 years, and the median duration of disease seven years. The Keitel function test (KFT) showed good correlation with the Ritchie articular index (RAI) (p less than 0.0001; r = 0.5) and the disability questionnaire (DQ) (p less than 0.0001; r = 0.6). The RAI and DQ correlated weakly with laboratory variables, while the KFT showed significant correlation with the erythrocyte sedimentation rate (ESR), C reactive protein (CRP), and plasma viscosity (PV) (p less than 0.001; r = 0.4; 0.3; 0.4). Only the KFT showed significant correlations with bone mass measurements (p less than 0.01; r = -0.3; -0.4), and the Larsen index at the right wrist (p less than 0.0001; r = 0.4). Consensus analysis suggested that the KFT is a useful single clinical test of disease activity in RA. The hand functional index (HFI), a component of the KFT, showed significant correlation with the total KFT (r = 0.9). Prospective drug trials are needed to establish the value of the HFI in the monitoring of patients with RA.

Handedness and deformities, radiographic changes, and function of the hand in rheumatoid arthritis.

The correlation of handedness with deformities, radiographic changes, and function of the hand was studied in a large group of patients with rheumatoid arthritis and a dominant right hand. There was no significant difference in the proportion of patients who had swan neck deformity, boutonnière deformity, uncorrectable ulnar deviation, and flexor tenosynovitis in the dominant and non-dominant hands. There were significantly greater radiological changes in the dominant hand, however, and the middle and index fingers were most severely affected. The severe involvement of these fingers may be related to their greater use in daily activities. There was also more severe functional impairment in the dominant hand.

Metacarpal bone mass in systemic lupus erythematosus

SummaryWe report the prevalence of metacarpal cortical thinning in systemic lupus erythematosus (SLE). Fifty-eight ambulant female patients attending a lupus clinic (mean age 32.4 years), were found to have significant thinning of metacarpal cortices (p<0.05) when compared with 63 normal females (mean age 34.1 years). However, metacarpal bone mass was within the normal range. Measurements were made at 6 metacarpals of the 2 hands using a computer-aided technique (digitized radiogrammetry). Femoral cortical width and Singh index at the left femur, as well as the vertebral index at L3 were also recorded. The trabecular indices were in the range of normality, but the SLE group had more patients in the immediately pre-osteopaenic range. Metacarpal bone loss was not related to disease duration or corticosteroid therapy. The prevalence of osteopenia in SLE is probably underestimated and the pathogenesis is likely to be multifactorial.

Prevalence of metacarpal osteopenia in young rheumatoid arthritis patients

SummaryThe aim of this study was to assess the prevalence of and diagnostic role of metacarpal osteopenia in rheumatoid arthritis (RA) and to evaluate its detectability using receiver operating characteristic (ROC) analysis. Metacarpal bone mineral density was measured in 98 patients with classical RA using a computer-assisted measure of 6 metacarpal diameters (radiogrammetry) in patients aged less than 50 years. Sensitivity and specificity of the technique in discriminating the RA patients from 85 normal controls and osteopenic RA subjects from their normopenic counterparts, was determined by standard statistical techniques. Clinical, laboratory and radiological variables were compared in their ability to explain the variance of metacarpal bone density. The prevalence of metacarpal osteopenia in RA was 55%. Prolonged disease and reduced function significantly differentiated osteopenic from non-osteopenic RA patients. Discriminant analysis of the RA and control groups showed that measurement of 6 metacarpals was more accurate than the 2nd metacarpal measurement alone in predicting the RA patients. The sum of 6 metacarpal combined cortical width (CCW) had a sensitivity of 61% and specificity of 68% in discriminating the RA patients from the controls. Receiver operating characteristic curves showed, not surprisingly, that objective measurement of bone diameters was superior to clinical or laboratory measures of disease activity in correctly classifying a randomly chosen RA patient as osteopenic or not. Metacarpal osteopenia is common in RA and it may be a useful measure of the disease in young patients.