Table 1.

Baseline characteristics of PsA patients by ACPA status

Characteristics	ACPA-positive patients	ACPA-negative patients	P-values
	(n = 105)	(n = 1891)
Demographic characteristics
Age, mean (s.d.), years	50.2 (11.3)	49.4 (11.6)	0.74
BMI, mean (s.d.), kg/m2	27.5 (5.0)	28.6 (5.4)	0.039
Female, %	52.9	44.2	0.086
Duration of arthritis symptoms, mean (s.d.), years	8.5 (8.6)	9.3 (8.5)	0.15
Duration of psoriasis symptoms, mean (s.d.), years	18.6 (13.3)	18.3 (12.9)	0.92
Disease characteristics
Tender joint count, mean (s.d.)	18.4 (16.7)	16.6 (16.4)	0.16
Swollen joint count, mean (s.d.)	15.1 (16.7)	8.5 (10.5)	<0.0001
DAS28, mean (s.d.)	5.26 (1.44)	4.77 (1.32)	0.0016
FFbH, % remaining functional capacity, mean (s.d.)	67.3 (19.9)	70.2 (21.5)	0.12
Erosive changes, % of patients	72.2	52.9	0.0003
Osteoporosis, % of patients	11.7	4.5	0.0034
Dactylitis, % of patients	67.6	50.6	0.0006
Enthesitis, % of patients	28.6	31.4	0.59
Nail psoriasis, % of patients	71.4	65.7	0.25
Joint involvement, % of patients
Polyarthritis	64.8	61.3	0.54
Mono-/oligoarthritis	23.8	30.0	0.19
DIP involvement	26.7	24.2	0.56
Axial involvement	19.0	18.3	0.80
Arthritis mutilans	0	2.6	0.11
Target lesion score, mean (s.d.)	7.3 (4.0)	7.1 (3.5)	0.45
BSA, % of patientsa
<3%	15.4	21.3
3–10%	38.5	39.5	0.37
11–20%	25.0	19.9
>20%	21.2	19.2
Laboratory parameters, mean (s.d.)
CRP, mg/l	19.2 (54.5)	12.1 (23.2)	0.20
ESR, mm/h	28.0 (24.1)	22.6 (19.0)	0.049

Demographic and disease characteristics of PsA patients at baseline (prior to initiation of adalimumab therapy) by ACPA status. P-values were calculated using the Wilcoxon rank sum test for continuous variables and the Fisher’s exact test for discrete variables.

^aValues do not total 100% due to rounding.

BSA: body surface area; FFbH: Funktionsfragebogen Hannover patient function questionnaire (higher scores correspond to greater function).