Table 1: Characteristics of the patients included in the study.

Cases (n=23) Controls (n=23)
Age (years) at T0 Median
(range)
53
(21-77)
55
(21-82)
Race/ethnicity
N, (%)
Whites 14
(61%)
14
(61%)
African-Americans 6
(26%)
6
(26%)
Hispanics 3
(13%)
2
(9%)
Asians 0
(0%)
1
(4%)
Common clinical features of SLE at T0
N, (%)
Tender joints 15
(65%)
15
(65%)
Swollen joints 7
(30%)
7
(30%)
Photosensitivity 11
(48%)
4
(17%)
Malar rash 5
(22%)
3
(13%)
Ulcers 3
(13%)
2
(9%)