Skip to main content
. Author manuscript; available in PMC: 2022 Nov 1.
Published in final edited form as: Arthritis Care Res (Hoboken). 2021 Sep 24;73(11):1561–1567. doi: 10.1002/acr.24397

Table 1.

Baseline characteristics of the systemic lupus erythematosus (SLE) cases and frequency-matched* controls, 2014–2015.

SLE Cases (n=462) mean (SD) or frequency (%) Controls (n=192) mean (SD) or frequency (%) p-value
mean (SD) or frequency (%) mean (SD) or frequency (%)

Age (years) SD 53.3 (12.3) 53.6 (14.0) NS
Sex a <0.001
 Female 430 (93.1) 154 (80.2)
 Male 32 (6.9) 38 (19.8)
Race NS
 White 233 (50.4) 107 (55.7)
 Black 208 (45) 77 (40.1)
 Other/unspecified b 21 (4.5) 8 (4.2)
Median Income NS
 Below US Median 198 (45.5) 70 (38.0)
 Above US Median 237 (54.5) 114 (62.0)
Poverty 87 (18.8) 45 (23.4) NS
Insurance NS
 None 10 (2.2) 7 (3.6)
 Medicaid c 112 (24.2) 47 (24.5)
 Medicare/age <65 yrs 68 (14.7) 13 (6.8)
 Medicare/age ≥65 yrs 66 (14.3) 29 (15.1)
 Private 198 (42.9) 90 (46.9)
 Other 8 (1.7) 6 (3.1)
Number of prescriptions (at time of visit) d
 Prescription medications 7 (3, 11) 2 (0, 5) <0.001
 Chronic prescription medications e 5 (2, 9) 1 (0, 4) <0.001
*

Frequency-matched by sex, race, age, and geography; NS=not significant (at 0.05 level)

a

given the rarity of SLE in males, an equivalent number of male controls to cases was recruited, thus the female to male ratio within controls differs compared to cases

b

Other/unspecified races include: American Indian and Alaska Native (AIAN) (n=8), Asian (n=6), other/unknown (n=15).

c

Participants with dual Medicaid/Medicare coverage (73 SLE and 16 controls) were included in the Medicaid category

d

number of prescribed medications reported by participant as “currently taking” at the time of study visit [reported as median (interquartile range)]

e

chronic medication use defined as ≥3 months