Table 3 Univariate and multivariate Cox regression analyses of risk factors of AVN in SLE patients

Demographic characteristics

 Gender

0.747 (0.363–1.536)

0.428

 Age at SLE onset ≤ 30

1.594 (1.052–2.413)

0.028*

1.616 (1.067–2.449)

0.023*

SLEDAI-2 K

0.983 (0.950–1.017)

0.317

Existing organ damage (SDI ≥ 1) at registration

2.894 (1.946–4.305)

 < 0.001**

2.610 (1.748–3.895)

 < 0.001**

Organ/system involvement up until registration

 Mucocutaneous

1.332 (0.793–2.238)

0.278

 Renal

0.845 (0.568–1.258)

0.407

 Neuropsychiatric

1.715 (0.993–2.962)

0.053

 Hematological

1.445 (0.984–2.123)

0.061

 Serositis

1.706 (1.048–2.779)

0.032*

 Arthritis

1.581 (1.051–2.377)

0.028*

1.642 (1.089–2.475)

0.018*

 PAH

3.064 (1.797–5.227)

 < 0.001**

Laboratory results up until registration

 Hypocomplementemia

1.305 (0.828–2.058)

0.251

 ANA

0.978 (0.241–3.965)

0.975

 Anti-dsDNA

1.008 (0.643–1.578)

0.973

 Anti-Sm

1.393 (0.863–2.247)

0.175

 Anti-RNP

1.934 (1.320–2.834)

0.001**

1.709 (1.162–2.515)

0.006**

 Anti-SSA

1.110 (0.758–1.625)

0.592

 Anti-SSB

1.023 (0.616–1.699)

0.929

 Anti-rib P

1.630 (1.040–2.552)

0.033*

 Positivity in aPLs

1.180 (0.726–1.921)

0.504

 Coombs

0.958 (0.651–1.409)

0.827

Treatment up until registration

 High dose GC at registration

1.949 (1.225–3.100)

0.005**

1.747 (1.092–2.795)

0.020*

 Hydroxychloroquine

0.706 (0.463–1.077)

0.106

 Immunosuppressants

1.332 (0.883–2.009)

0.172