Table 2.

Variables associated with lumbar sBMD over time

	Beta	95 % CI	p-value
Intercept	1.187	1.062 to 1.312	<0.001
Treatment with prednisone	0.002	−0.034 to 0.037	0.93
Study center			<0.001
Male gender	−0.033	−0.072 to 0.007	0.11
Age	−0.004	−0.005 to −0.003	<0.001
Weight	0.004	0.002 to 0.005	<0.001
Rheumatoid factor positivity	−0.064	−0.101 to −0.026	<0.001
AUC DAS28	−0.019	−0.036 to −0.002	0.03

This mixed model includes 145 patients (61 % of the trial population) with 374 sBMD measurements. Fixed effects, except for the beta’s of the different study centers, are described in the table. Study center, higher age, lower weight, rheumatoid factor positivity, and higher DAS28 during the trial were significantly related with lower sBMD values at the lumbar spine

sBMD standardized bone mineral density, CI confidence interval, DAS28 disease activity score based on 28 joints, AUC area under the curve