Table 1.

Characteristics of the studied patients and controls.

	SLE + MCTD (N = 272)	RA (N = 280)	Control (N = 280)	F/P
VZV antibody concentration (mIU/mL)	2936.1 (1982.0–3890.2)	1774.8 (1343.1–2206.5)	2960.7 (2466.2–3455.2)	0.017
Positive rate of VZV (%)	95.6	97.1	98.9	0.057
Mean age (years, M ± SD)	49.5 ± 14.3	50.0 ± 13.3	50.1 ± 10.2	0.826
Duration of disease (years, M ± SD)	5.3 ± 4.7	8.3 ± 7.6	NA	0.000
Female n (%)	212(77.9%)	216(77.1%)	226(81.0%)	0.501
HZ history n (%)	22(8.1%)	9(3.2%)	8(2.9%)	0.005
Mean time from disease onset to HZ (years, M ± SD)	3.3 ± 1.9	6.4 ± 2.8	NA	0.002