No abstract

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 ofhand 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 23-/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 < 0O0001), 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, 950/o 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),

Objective. To measure hand bone mineral content (BMC) by dual x-ray absorptiometry and to seek clinical correlates in patients with rheumatoid arthritis (RA), in a prospective, longitudinal study.Methods. Eighty-one patients with non-steroidtreated RA were assessed at baseline and at month 12, for hand BMC and for disease activity and severity. Hand BMC in patients was compared with that in a control group of 95 normal volunteers, and rate of loss was compared with that in 37 controls.Results. At the initial assessment, male and female patients with RA had lower hand BMC than controls, after correction for age, height, and weight (mean reduction 7.5% in men [P = 0.0031 and 7.8% in women [P = 0.011). After 1 year, there was a further loss of hand BMC in patients (median loss 3.25% in men [P = 0.0011 and 1.46% in women [P = 0.05]), but normal controls did not have significant changes in their hand BMC. In patients with disease duration of <2 years at study entry, the parameters of disease activity improved over 1 year, but they lost significant amounts of hand BMC. Hand BMC loss correlated with baseline C-reactive protein levels. In those with RA of