Table 2. Associations between colorectal adenoma and colorectal cancer or colorectal neoplasia (both combined) and IBS with adjustment for relevant risk factors using proportion hazards regression models.

	Adenoma				CRC				Colorectal neoplasia
Variable	HR	95% CI	aHR	95% CI	HR	95% CI	aHR	95% CI	HR	95% CI	aHR	95% CI
IBS (Y/N)	1.43	(1.23–1.67)***	1.21	(1.02–1.42)*	1.70	(1.35–2.15)***	1.20	(0.94–1.53)	1.52	(1.34–1.73)***	1.22	(1.07–1.40)**
Age	1.03	(1.02–1.04)***	1.02	(1.01–1.02)***	1.05	(1.04–1.06)***	1.05	(1.04–1.06)***	1.04	(1.03–1.04)***	1.03	(1.02–1.03)***
Gender (M/F)	2.34	(2.02–2.71)***	2.14	(1.80–2.55)***	1.53	(1.22–1.91)**	1.31	(1.04–1.64)*	2.07	(1.84–2.34)***	1.87	(1.62–2.15)***
BMI (⩾30/<30)	1.31	(1.04–1.66)*	1.19	(0.93–1.54)	1.38	(0.96–1.98)	1.27	(0.88–1.84)	1.33	(1.09–1.61)**	1.33	(1.09–1.62)**
CRC family history (Y/N)	1.27	(0.83–1.97)	1.59	(1.03–2.46)*	1.05	(0.50–2.22)	1.54	(0.72–3.27)	1.13	(0.76–1.66)	1.47	(0.99–2.17)
Smoking (Y/N)	1.93	(1.67–2.23)***	—	—	1.06	(0.82–1.37)	—	—	1.65	(1.45–1.87)***	—	—
Drinking (Y/N)	1.83	(1.57–2.12)***	1.36	(1.15–1.61)**	1.05	(0.81–1.37)	—	—	1.57	(1.38–1.79)***	1.25	(1.08–1.44)**
Exercise frequency
Medium/few	1.07	(0.90–1.28)	—	—	0.86	(0.65–1.13)	—	—	1.00	(0.86–1.16)	0.85	(0.73–0.98)*
High/few	1.20	(0.99–1.46)	—	—	1.25	(0.93–1.68)	—	—	1.22	(1.04–1.44)*	0.61	(0.48–0.79)***
Education level
Medium/low	0.75	(0.64–0.88)**	0.79	(0.67–0.94) **	0.61	(0.48–0.79)**	—	—	0.71	(0.62–0.81)***	—	—
High/low	0.59	(0.45–0.78)**	0.58	(0.43–0.78)**	0.43	(0.27–0.69)**	—	—	0.54	(0.43–0.68)***	—	—
Mets (Y/N)	1.38	(1.18–1.60)***	—	—	1.33	(1.04–1.69)*	—	—	1.34	(1.18–1.53)***	—	—
Diabetes (Y/N)	1.01	(0.78–1.31)	—	—	1.87	(1.36–2.59)**	1.43	(1.03–1.99)*	1.24	(1.02–1.52)*	—	—
Hypertension (Y/N)	1.34	(1.16–1.55)***	1.19	(1.02–1.40)*	1.34	(1.07–1.68)*	—	—	1.33	(1.18–1.50)**	—	—

***P<0.0001, **P<0.01, *P<0.05.