In this SLE population, disease activity was predictive of deleterious changes in body composition, including increases in BMI and fat mass. Patient-related variables were also important predictors of body composition change with exercise independently predicting an increase in fat-free mass, and smoking predictive of loss of total body BMD. In contrast, CS-related variables were not found to have harmful effects on body composition. Change in fat-free mass, and not fat mass, was predictive of change in total body BMD.

The objectives were to determine the body composition, and the effects of disease and corticosteroid therapy on body composition, in a population of female patients with systemic lupus erythematosus (SLE). All female SLE patients managed through a single centre were invited to participate in a cross-sectional study of body composition. Data were collected by standardized interview and examination, and review of medical records. Body composition was assessed by dual-energy X-ray absorptiometry (DXA). Eighty-two subjects were evaluated, 30 of whom were post-menopausal. Univariate linear regression analysis revealed a significant association of reduced fat-free mass with SLE severity [as measured by the Systemic Lupus International Collaborative Clinics (SLICC)] (P = 0.020), a history of corticosteroid exposure (P = 0.043) and age (P = 0.048). Reduced total body bone mineral density (BMD) was also significantly associated with SLICC (P < 0.001) and corticosteroid exposure (P = 0.017), and with age (P < 0.001), post-menopausal status (P = 0.003) and the duration of menopause (P < 0.001). Stepwise multiple linear regression analysis revealed a significant association between fat-free mass and total body, lumbar spine and femoral neck BMD (P = 0.007, P = 0.025, P = 0.003, respectively). Fat mass was significantly associated only with lumbar spine BMD (P = 0.008). In this SLE population, disease severity and corticosteroid exposure were independently associated with a negative effect both on total body BMD and on fat-free mass. Fat-free mass was a significant predictor of lumbar spine, femoral neck and total body BMD.

Low dose pulse oral methotrexate (MTX) is a well established treatment for rheumatoid arthritis, and short term open studies have suggested beneficial effects of MTX in SLE. This study was designed to investigate MTX treatment maintenance rates in SLE using life table analysis, and to determine whether MTX use was associated with a dose reduction of concomitant steroid therapy. All SLE patients managed by physicians affiliated with a single centre were studied cross-sectionally. Information regarding disease variables and drug use were ascertained by interview and chart review. Drug therapy data including dates of treatment and indications for treatment were analysed using Kaplan-Keier life table methods. Among 101 subjects with SLE, 25 MTX treatment episodes were observed in 24 subjects. The period studied totalled 19766 patient-days, with a median (range) duration of observed MTX treatment of 14.4 (5.1-41.6) months. The median (range) initial and peak MTX doses with 7.5 (2.5-10)mg/wk and 10 (7.5-15) mg/week respectively. The principal indication for commencing methotrexate therapy was arthritis. Only two subjects terminated treatment for toxicity, with the most common reason for termination being remission. The cumulative probability of continuing treatment was 68% at 12 months and 61% at 24 months, or 75% and 71% respectively if cessations for remission were excluded. The median (interquartile range) monthly steroid intake during MTX therapy [279.4 (193.4-492.9)mg] was somewhat lower than during the 6 months prior to [298.1 (237.9-531.4)428.8)mg] MTX therapy, but this difference was not significant. A total of 36% of subjects reduced their steroid dose during MTX therapy, but this reduction was not significant. Treatment of SLE with MTX, predominantly for arthritis, was well tolerated over prolonged periods of observation. Toxicity of sufficient severity to lead to treatment termination was uncommon. A subset of subjects were able to reduce steroid intake during MTX therapy, but no overall reduction in steroid dose was observed.

The aim of this study was to measure the urinary excretion of the pyridinium cross-links of collagen and to determine their usefulness as markers of reduced bone mineral density in systemic lupus erythematosus (SLE). All female SLE patients managed at a single centre were invited to participate in a cross-sectional study of urinary pyridinium cross-links excretion (HPLC), bone mineral density (DXA), and SLE-related variables. Ninety-one women with SLE were studied, 35 of whom were postmenopausal. Pyridinoline/Creatinine (Pyd/Cr) and deoxypyridinoline/Cr (Dpd/Cr) levels in postmenopausal women were significantly increased compared with premenopausal values (p = 0.010 and p = 0.004, respectively). Univariate linear regression analysis revealed a significant association of Dpd/Cr with reduced femoral neck and lumbar spine BMD (p = 0.001, p<0.001), and of Pyd/Cr with reduced femoral neck BMD (p = 0.020). In addition, the association of Pyd/Cr with reduced lumbar spine BMD approached significance (p = 0.055). Stepwise multiple linear regression analysis adjusting for other variables confirmed a significant association of Dpd/Cr with reduced lumbar spine BMD (p = 0.006), and a significant association of both Pyd/Cr and Dpd/Cr with postmenopausal status (p = 0.003, p<0.001). It was concluded that in this SLE population, the urinary excretion of Dpd/Cr was a useful marker of reduced BMD at the lumbar spine. Menopausal status was a major predictor of cross-links excretion in SLE.