Table 1.

Baseline data of matched cohorts with and without bDMARD treatment with P values of group differences

		bDMARD	Control	P value
n		1352	1352
Age	Years	55±12	53±12	<0.001
Female proportion		36%	36%	0.689
CCI		2.8±1.8	2.6±1.8	0.008
Time since AS diagnosis	Years	12±8	12±8	0.831
Methotrexate	Years	6±18	4±11	<0.001
Sulfasalazine	Years	4±13	4±13	0.409
NSAID	Years	20±19	20±24	0.833

AS, ankylosing spondylitis; bDMARD, biological disease-modifying antirheumatic drugs; CCI, Charlson Comorbidity Index; NSAID, non-steroidal anti-inflammatory drugs.