Osteopontin, osteoprotegerin and musculoskeletal ultrasound findings in first-degree relatives of rheumatoid arthritis: potential markers of preclinical disease

Table 1 Rheumatoid factor and anti-citrullinated protein antibodies in the studied groups

	RA (n = 20)	FDRs (n = 25)	Controls (n = 10)	P
RF (< 15.9 IU/ml)
Negative No. (%)	2 (10.0%)	25 (100.0%)	10 (100.0%)	< 0.001^*
Positive No. (%)	18 (90.0%)	0 (0.0%)	0 (0.0%)	< 0.001^*
Min. – Max.	9.0–697.0	4.80–12.70	8.20–11.75	< 0.001^*
Mean ± SD.	133.28 ± 176.38	9.21 ± 1.9	9.92 ± 1.19
Median	68.40	9.19	9.40
Significance between groups	p₁ < 0.001^, p₂ < 0.001^, p₃ = 0.358
ACPA(< 20 U/ml)
Negative No. (%)	3(15%)	25(100%)	10(100%)	< 0.001^*
Positive No. (%)	17(85%)	0 (0%)	0 (0%)	< 0.001^*
Min. – Max.	7.0–915.0	5.0–17.60	6.50–10.70	< 0.001^*
Mean ± SD.	226.83 ± 266.19	11.06 ± 3.43	9.53 ± 1.34
Median	107.0	11.20	9.75
Significance between groups	p₁ < 0.001^, p₂ < 0.001^, p₃ = 0.131

p value for Kruskal Wallis test for comparing between the different groups; Significance between groups was done using Mann Whitney test; p₁: p value for comparing between RA patients and FDRs; p₂: p value for comparing between RA patients and controls; p₃: p value for comparing between FDRs and controls; *: Statistically significant at p ≤ 0.05
RA: rheumatoid arthritis; FDRs: first degree relatives; RF: rheumatoid factor; ACPA: anti-citrullinated protein antibodies

ISSN: 1471-2474