Elevated Rheumatoid Factor Associates with Dry Eye in Patients with Common Autoimmune Diseases

Figures & data

Table 1 Demographic and Clinical Characteristics of the Common Autoimmune Diseases Patients

Variables	Overall (n = 117)	With Dry Eye (n = 59)	Without Dry Eye (n = 58)	P
Disease (n, %)				0.199
RA	72 (61.54)	39 (54.17)	33 (45.83)
SLE	19 (16.24)	6 (31.58)	13 (68.42)
pSS	26 (22.22)	14 (53.85)	12 (46.15)
Age (years)	53.19 ± 12.91	54.68 ± 12.23	51.67 ± 13.49	0.209
Gender (female, %)	111 (94.87)	57 (51.35)	54 (48.65)	0.390
Duration of the disease (years)	4.81 ± 5.64	4.69 ± 4.75	4.93 ± 6.46	0.820
STT-I (mm)	6.55 ± 5.97	3.49 ± 4.02	10.66 ± 6.01	<0.001
TBUT (second)	4.79 ± 3.29	2.73 ± 1.41	10.9 ± 3.34	<0.001
Ocular staining score	NA.	4.25 ± 2.15	NA.	NA.
WBC (×10^9/L)	5.64 ± 3.16	5.04 ± 2.29	6.25 ± 3.78	0.13
NE (×10^9/L)	3.84 ± 2.61	3.44 ± 2.25	3.64 ± 2.43	0.375
LY (×10^9/L)	1.63 ± 1.23	1.53 ± 0.71	1.73 ± 1.59	0.382
Hb (g/L)	118.37 ± 16.24	116.64 ± 16.23	120.12 ± 16.21	0.249
PLT (×10^9/L)	225.35 ± 92.85	222.81 ± 92.64	227.95 ± 93.81	0.766
CR-S (mmol/L)	53.63 ± 19.28	51.44 ± 10.79	55.86 ± 25.07	0.216
AST (IU/L)	28.72 ± 39.47	24.61 ± 14.84	32.9 ± 53.95	0.795
ALT (IU/L)	29.32 ± 58.04	22.61 ± 19.24	36.16 ± 79.9	0.208
ALP (IU/L)	78.71 ± 42.25	83.02 ± 51.2	74.33 ± 30.42	0.967
GGT (IU/L)	29.67 ± 20.45	43.49 ± 61.48	36.64 ± 46.3	0.627
ALB (g/L)	36.66 ± 4.71	36.37 ± 5.02	36.95 ± 4.39	0.502
IgG (g/L)	18.22 ± 8.54	19.12 ± 8.18	17.31 ± 8.86	0.252
IgA (g/L)	3.33 ± 2.25	3.87 ± 2.55	2.78 ± 1.75	0.008
IgM (g/L)	1.58 ± 2.53	1.96 ± 3.47	1.21 ± 0.67	0.109
C3 (g/L)	0.899 ±0.25	0.89 ± 0.25	0.91 ± 0.25	0.541
C4 (g/L)	0.18 ± 0.09	0.17 ± 0.1	0.18 ± 0.08	0.474
RF (IU/mL)	93.84 ± 225.57	156.83 ± 304.59	29.75 ± 29.28	<0.001
CRP (mg/L)	14.27 ± 24.14	16.16 ± 25.24	15.23 ± 24.62	0.680
ESR (mm/h)	33.95 ± 23.47	37.1 ± 24.01	30.74 ± 22.66	0.144

Abbreviations: RA, Rheumatoid arthritis; SLE, Systemic lupus erythematosus; pSS, primary Sjogren’s syndrome; CRP, C-reactive protein; RF, rheumatoid factor; WBC, white blood cell; Hb, hemoglobin; ESR, erythrocyte sedimentation rate; IgG, immunoglobulin G; IgA, immunoglobulin A; IgM, immunoglobulin M; C3, complement 3; C4, complement 4; NE, neutrophil; LY, lymphocyte; ALT, alanine aminotransferase; AST, aspartate aminotransferase; ALB, albumin; ALP, alkaline phosphatase; GGT, gamma glutamyl transferase; CR-S, creatinine; STT-I, Schirmer-I tear test; TBUT, Invasive tear film break-up time; NA., not applicable.

Table 2 The Correlation Between RA and Dry Eye Index in Common Autoimmune Diseases Patients

	RF
	R	P
STT-I (mm)	−0.263	0.004
TBUT (second)	−0.289	0.002

Abbreviations: STT-I, Schirmer-I tear test; TBUT, Invasive tear film break-up time; RF, rheumatoid factor.

Figure 1 The ROC curve of the rheumatoid factor levels for dry eye with common autoimmune diseases. The AUC of the ROC curve for rheumatoid factor was estimated to be 0.73 (95% confidence interval [CI]: 0.639–0.821, P < 0.001).

Abbreviations: ROC, receiver operating characteristic; AUC, area under the curve.