TNF-α inhibitor users were defined as the patients who were treated with TNF-α
inhibitors at any point during the first and follow-up visits; the baseline was
defined as the time of enrollment for patients who were using TNF-α inhibitors
at the time of enrollment or as the time at which patients started using TNF-α
inhibitors after enrollment. TNF-α inhibitor users received subcutaneous
administration of TNF-α inhibitors, including biosimilar etanercept
(Yisaipu®; Sunshine Guojian Pharmaceutical Co., Ltd, Shanghai,
China) or adalimumab (AbbVie, Ludwigshafen, Germany).18 (link)–20 (link, link)Subsequent visits were scheduled by physician according to the patients’
conditions. TNF-α inhibitor users had at least one 3-month follow-up after the
baseline for analyzing the effect of BMI on treatment response to TNF-α
inhibitors.