Table 2

Baseline characteristics of patients with rheumatic immune-mediated inflammatory diseases and healthy controls with a confirmed diagnosis of COVID-19

Patient characteristicsPatients (n=347)Healthy controls (n=133)
Age, years—mean (SD)56 (13)54 (13)
Female sex—no. (%)240 (69)102 (77)
Male sex—no. (%)107 (31)31 (23)
Body mass index, kg/m2—mean (SD)25 (5)25 (4)
Caucasian race—no. (%)282 (83)122/131 (93)
Educational level—no. (%)
 High149 (45)68 (53)
 Middle114 (35)39 (30)
 Low67 (20)21 (16)
Current smoking status—no. (%)27 (8)2 (2)
Coexisting conditions—no. (%)
Cardiovascular disease34 (10)7 (5)
Chronic pulmonary disease42 (12)9 (7)
Diabetes14 (4)0 (0)
Obesity65 (19)14 (10)
COVID-19-related symptoms—no. (%)
Sore throat154 (44)54 (41)
Cough183 (53)66 (50)
Rhinorrhoea206 (59)81 (61)
Dyspnoea124 (36)39 (29)
Fever138 (40)58 (44)
Loss of taste or smell163 (47)69 (52)
Headache192 (55)59 (44)
Excessive tiredness229 (66)70 (53)
General malaise148 (43)56 (42)
Vomiting and/or diarrhoea46 (13)11 (8)
Diagnosis of COVID-19—no. (%)
PCR test249(72)95 (71)
 Solely negative results50 (14)29 (22)
 At least one positive result199 (57)66 (50)
RBD-Ab bridging ELISA296 (85)125 (94)
 Solely negative results30 (9)9 (7)
 At least one positive result291 (84)120 (90)
Disease severity of COVID-19
Asymptomatic—no. (%)45 (13)10 (8)
Hospitalisation—no. (%)23 (7)1 (0.7)
 Duration, days—median (IQR)10 (2–11)15 N.A.
 ICU admission—no. (%)3 (0.9)0 (0)
 Deceased—no. (%)1 (0.3)0 (0)
  • Data are mean (SD), median (IQR) or n (%).

  • Only data on educational level and race had missing values, valid percentages are shown. Duration of hospitalisation was only assessed in patients who survived COVID-19.

  • ICU, intensive care unit; N.A., not available; RBD-Ab, receptor binding domain antibody.