Table 5. Predictors of BMD-LS, BMD-FN and BMD-H (independent variables used: age, female gender, postmenopausal status, BMI, disease duration, cumulative GC dose, pretreatment with bDMARD, pretreatment with BP, ESR, CRP, seropositivity) in RA subgroups according to disease duration ((A) all patients; (B) patients without bisphosphonates); multiple linear regression analysis.

(A)
RA with disease duration ≤2 years (n=386)				RA with disease duration >2 years (n=700)
Site	BMD-LS	BMD-FN	BMD-H	Site	BMD-LS	BMD-FN	BMD-H
Age	ns	<0.001	<0.001	Age	0.034	<0.001	<0.001
Female	ns	0.011	0.001	Female	0.018	ns	ns
PMP	<0.001	ns	ns	PMP	<0.001	<0.001	<0.001
BMI	0.002	<0.001	<0.001	BMI	<0.001	<0.001	<0.001
DD	ns	ns	ns	DD	ns	ns	ns
cGCD	ns	ns	ns	cGCD	0.006	<0.001	<0.001
bDMARD	0.034	ns	ns	bDMARD	<0.001	0.009	0.008
BP	ns	ns	ns	BP	0.027	ns	0.016
ESR	ns	ns	ns	ESR	0.024	ns	0.004
CRP	ns	ns	ns	CRP	ns	ns	ns
Seropositivity	0.031	ns	ns	Seropositivity	ns	ns	ns
R2	0.166	0.224	0.279	R2	0.210	0.309	0.401
P value	<0.001	<0.001	<0.001	P value	<0.001	<0.001	<0.001
(B)
RA with disease duration ≤2 years (n=357)				RA with disease duration >2 years (n=577)
Site	BMD-LS	BMD-FN	BMD-H	Site	BMD-LS	BMD-FN	BMD-H
Age	0.033	<0.001	<0.001	Age	0.060	<0.001	<0.001
Female	<0.001	0.004	<0.001	Female	0.027	ns	ns
PMP	ns	ns	ns	PMP	0.001	<0.001	<0.001
BMI	0.011	<0.001	<0.001	BMI	<0.001	<0.001	<0.001
DD	0.018	ns	ns	DD	ns	0.028	ns
cGCD	ns	ns	ns	cGCD	0.021	0.020	<0.001
bDMARD	0.003	ns	ns	bDMARD	0.001	0.008	0.008
ESR	ns	ns	ns	ESR	0.007	ns	0.012
CRP	ns	ns	ns	CRP	ns	0.011	ns
Seropositivity	0.006	ns	ns	Seropositivity	ns	ns	ns
R2	0.210	0.235	0.278	R2	0.202	0.364	0.428
P value	<0.001	<0.001	<0.001	P value	<0.001	<0.001	<0.001

Positive associations with BMD are highlighted in bold font.

bDMARDs, biologic disease-modifying antirheumatic drugs; BMD, bone mineral density; BMD-FN, BMD femoral neck; BMD-H, BMD total hip; BMD-LS, BMD lumbar spine; BMI, body mass index; BP, bisphosphonates; cGCD, cumulative glucocorticoid dose; CRP, C reactive protein; DD, disease duration; ESR, erythrocyte sedimentation rate; Female, female gender; ns, not significantPMP, postmenopausal statusRArheumatoid arthritis