Table II.

Comparison of levels of serum inflammatory factors between RE group and NERD group (mean ± SD, pg/ml).

Group	n	IL-1β	IL-8	TNF-α
NERD	12	26.8±3.7	18.6±3.3	30.4±4.2
Grade I RE	15	42.5±8.2a	37.5±4.5a	44.6±5.7a
Grade II RE	18	54.8±7.2a,b	46.7±5.5a,b	57.4±5.6a,b
Grade III RE	15	65.6±8.3a,b	72.2±6.1a–c	63.2±6.3a,b

^aP<0.05 vs. NERD group

^bP<0.05 vs. grade I RE group

^cP<0.05 vs. grade II RE group. RE, reflux esophagitis; NERD, non-erosive reflux disease; IL-1β, interleukin-1β; IL-8, interleukin-8; TNF-α, tumor necrosis factor-α.