Comparison of peripheral quantitative computed tomography forearm bone density versus DXA in rheumatoid arthritis patients and controls

Rheumatoid arthritis (RA) has been associated with osteoporosis. Quantitative computed tomography (QCT) is capable of assessing bone density and composition. We found lower bone density in RA compared to controls. Age and RA duration influenced bone density. QCT may be useful to assess bone metabolism in RA.

INTRODUCTION

RA is associated with generalized and periarticular osteoporosis. In addition to DXA that determines areal bone mineral density (BMD), peripheral QCT also detects volumetric BMD. QCT differentiates between total, trabecular, and cortical BMD. Here, we compared DXA and QCT in RA patients and healthy controls.

METHODS

BMD of 57 female RA patients and 32 age-matched healthy female controls were assessed by DXA. QCT of the forearm ultradistal region was also performed. Densitometry data were correlated with age, disease duration, disease activity, serum CRP, and anti-CCP levels.

RESULTS

Total bone density (310.4 ± 79.7 versus 354.0 ± 54.1 mg/cm³; p = 0.007) and attenuation (0.37 ± 0.05 versus 0.40 ± 0.03 1/cm; p = 0.001), trabecular density (157.6 ± 57.0 versus 193.8 ± 48.7 mg/cm³; p = 0.005) and attenuation (0.28 ± 0.03 versus 0.32 ± 0.04 1/cm; p < 0.0001), and cortical density (434.3 ± 115.8 versus 492.5 ± 64.0 mg/cm³; p = 0.006) and attenuation (0.44 ± 0.07 versus 0.47 ± 0.04 1/cm; p = 0.004) were significantly lower in RA. Both lumbar and femoral neck BMD, as well as T-scores, were significantly lower in RA versus controls (p < 0.001 in all cases). In RA, total and cortical QCT attenuation and density were associated with age, the presence of RA, and their combination. In contrast, trabecular density and attenuation were only affected by the presence of the disease but not by age. Also in RA, total trabecular and cortical density as determined by QCT significantly correlated with lumbar and/or femoral neck BMD as measured by DXA. Finally, anti-CCP seropositivity was associated with lower trabecular density and attenuation.

CONCLUSIONS

Both DXA and QCT may be suitable to study bone metabolism in RA. Areal BMD determined by DXA may correlate with volumetric bone density measured by QCT. Moreover, trabecular osteoporosis may be associated by the underlying autoimmune-inflammatory disease, while cortical osteoporosis may rather be age-related.

Pregnancy outcome in idiopathic inflammatory myopathy

The aim of our study was to assess the prevalence and outcome of pregnancy in idiopathic inflammatory myopathy patients who became pregnant after the onset of the disease. Female idiopathic inflammatory myopathy patients (173) were included in our study. The patients' charts and clinical data were retrospectively analyzed. One hundred and four female idiopathic inflammatory myopathy patients had 186 pregnancies, but only nine of these patients (4 polymyositis-PM, 5 dermatomyositis-DM) became pregnant after the onset of the disease. Nine patients with pregnancies after the disease onset had 14 gravidities. Six pregnancies resulted in normal deliveries, two ended in prematurity, six ended in abortions (two induced abortions). Regarding the four patients (3 PM, 1 DM) with active disease at the time of pregnancy, two pregnancies ended in prematurity, four ended in spontaneous abortion and one healthy baby delivered. The other five patients (2 PM, 3 DM) with the disease in remission had uneventful pregnancies and healthy babies were delivered. Treatment was not required during pregnancy in case of two dermatomyositis patients with long lasting remission. New onset dermatomyositis developed in one patient in her pregnancy's third trimester. The mean weight of newborns in the active myositis cases was 2,193 (1,680-2,700) g; while in patients with remission was 3,167 (2,800-3,800) g. The active maternal disease in idiopathic inflammatory myopathy (IIM) might result intrauterin retardation and death. Disease activity in active and new-onset cases could be controlled by increasing the dose of corticosteroid.

Functional outcome and quality of life in adult patients with idiopathic inflammatory myositis

OBJECTIVES

To present the outcome of patients with idiopathic inflammatory myositis, focusing on functional ability and quality of life.

METHODS

Analysis was performed using data from 105 adult patients with definitive polymyositis, dermatomyositis or overlap myositis, who were followed up at a single centre. The diagnosis was made between 1979 and 2000 based on Bohan and Peter's criteria. Functional ability was assessed after a minimum follow-up of 3 yr with the Health Assessment Questionnaire Disability Index (HAQDI) and quality of life was measured with the Short Form 36-item questionnaire (SF-36).

RESULTS

Fifteen patients in our cohort died and 87 participated in the evaluation of functional outcome. Functional ability after a median follow-up of 107.1 months (range 36.4-273.3) was heterogeneous. The median HAQDI score was 0.875 (range 0-2.875). Polyphasic or chronic-progressive disease course, osteoporosis and long-term follow-up were predictive of higher HAQDI scores. In terms of quality of life, significant differences from population norms were shown in all domains of the SF-36. There were no significant differences in the SF-36 scores among the patients according to clinicopathological subset or disease course.

CONCLUSIONS

Although the mortality of our cohort was favourable, myositis continues to have a great impact on life in the medium and long term. The present work indicates that myositis patients have a significantly poorer quality of life than the normal population, but there was no difference among the patients according to clinicopathological subsets.