Table 2.

Risk of IBS according to Quartiles of baseline fatty liver index

	Quartile 1	Quartile 2	Quartile 3	Quartile 4	P for trend
No. of participants	98,371	99,289	99,714	99,464
No. of incident IBS	1882	1797	1701	1749
Follow-up, person-years	1,192,803	1,197,965	1,199,435	1,185,959
Follow-up, years
Mean ± SD	12.1 ± 1.8	12.1 ± 1.8	12.0 ± 1.9	11.9 ± 2.1
Median (IQR)	12.4 (11.7–13.1)	12.4 (11.6–13.1)	12.4 (11.6–13.1)	12.3 (11.6–13.1)
Hazard ratio for incident IBS (95%CI, P value)
Adjusted model 1	Reference	1.15 (1.08–1.23)	1.24 (1.16–1.33)	1.36 (1.27–1.46)	< 0.001
Adjusted model 2	Reference	1.13 (1.06–1.21)	1.20 (1.12–1.28)	1.27 (1.19–1.37)	< 0.001
Adjusted model 3	Reference	1.12 (1.05–1.20)	1.17 (1.10–1.26)	1.21 (1.13–1.30)	< 0.001

Note: Adjusted model 1: Age and gender were adjusted; Adjusted model 2: Townsend deprivation index, education level, ethnicity, smoking status, and alcohol drinking were additionally adjusted; Adjusted model 3: IPAQ (International Physical Activity Questionnaire), and type 2 diabetes were additionally adjusted; P for trend was calculated by using median value (10.5, 32.2, 61.2, and 88.6) of each fatty liver index quartile

IBS irritable bowel syndrome, SD standard deviation, IQR inter-quartile range