Table 3

Multivariate regression analysis for TREC levels

Predictor	PBMCs		CD4⁺CD45RA⁺		CD8⁺CD45RA⁺
Predictor	Regression coeff	p Value	Regression coeff	p Value	Regression coeff	p Value
Age	−0.101	<0.001	−0.099	<0.001	−0.095	<0.001
Sex	0.657	0.031	0.712	0.014	0.701	0.030
Diagnosis aSpA	−3.442	0.004	−2.566	0.023	−2.651	0.034
Diagnosis RA	−4.201	<0.001	−2.844	0.008	−3.248	0.006
Interaction age–aSpA	0.059	0.021	0.051	0.038	0.047	0.086
Interaction age–RA	0.076	0.001	0.053	0.012	0.057	0.017
Ki67⁺ cells	−0.132	0.004	−0.107	0.015	−0.654	0.176

Multivariate regression analysis with TREC levels of PBMCs or naïve T-cell subsets (CD4⁺CD45RA⁺ and CD8⁺CD45RA⁺) of patients with aSpA and patients with RA as dependent variables as well as age, sex, diagnosis, interaction age*diagnosis and proliferating cells (as indicated by the prevalence of Ki67⁺ cells) as predictors. aSpA, axial spondyloarthritis; PBMCs, peripheral blood mononuclear cells; RA, rheumatoid arthritis; TREC, T-cell receptor excision circle.