Clinical correlations with Porphyromonas gingivalis antibody responses in patients with early rheumatoid arthritis

Table 2 Age and sex of the early rheumatoid arthritis group and comparison groups^a

			Patients
Demographic categories	Age-similar hospital personnel ( N = 19)	Blood bank donors ( N = 53)	Systemic lupus erythematosus ( N = 17)	Other CTD ( N = 17)	Early RA ( N = 50)	Late RA ( N = 43)
Age, mean (range)^b	48 (36 to 80)	N/A	44 (25 to 59)	50 (27 to 88)	53 (30 to 80)	60 (21 to 85)
Sex, females/males^c	7/12	N/A	17/17	15/17	36/14	31/12

^aCTD: connective tissue disease; N/A: not available; RA: rheumatoid arthritis. ^bFor comparison of age in early RA group vs. late RA group, P = 0.01; for early RA vs. systemic lupus erythematosus, P = 0.003. There were no other significant differences in age among the groups. ^cRegarding sex distribution, healthy hospital personnel, who were primarily men, were significantly different from each of the patient groups, which were composed primarily of women (P ≤ 0.01). The members of the lupus group, which was exclusively female, were significantly different than both RA patient groups (P < 0.05).