Table 4.

Risk of any polyp overall and by subgroups in patients with IBD, UC and CD, and matched general population comparators.

	IBD					UC					CD
Group	No. of events [%]		Incidence rate [95% CI] per 10 000 person-years		aHRa [95% CI]	No. of events [%]		Incidence rate [95% CI] per 10 000 person-years		aHRa [95% CI]	No. of events [%]		Incidence rate [95% CI] per 10 000 person-years		aHRa [95% CI]
	IBD	Ref	IBD	Ref		UC	Ref	UC	Ref		CD	Ref	CD	Ref
Overall	1648 [3.9%]	1143 [2.7%]	46.1 [43.9–48.3]	34.2 [32.2–36.2]	1.23 [1.12–1.35]	1241 [4.3%]	820 [2.8%]	50.9 [48.1–53.7]	35.6 [33.1–38.0]	1.31 [1.17–1.46]	407 [3.2%]	323 [2.5%]	35.7 [32.3–39.2]	31.2 [27.8–34.6]	1.06 [0.89–1.27]
Follow-up
0 to <1 year	202 [0.5%]	267 [0.6%]	49.9 [43.0–56.8]	68.4 [60.2–76.6]	0.72 [0.58–0.89]	151 [0.5%]	196 [0.7%]	53.9 [45.3–62.5]	72.5 [62.3–82.6]	0.73 [0.57–0.93]	51 [0.4%]	71 [0.6%]	40.9 [29.7–52.2]	59.2 [45.5–73.0]	0.70 [0.46–1.04]
1 to <5 years	506 [1.3%]	371 [1.0%]	38.6 [35.3–42.0]	30.1 [27.0–33.1]	1.13 [0.95–1.34]	382 [1.4%]	261 [1.0%]	42.2 [38.0–46.4]	30.4 [26.7–34.1]	1.23 [1.01–1.50]	124 [1.0%]	110 [1.0%]	30.7 [25.3–36.0]	29.3 [23.8–34.7]	0.91 [0.66–1.25]
5 to <10 years	482 [1.8%]	280 [1.1%]	46.9 [42.7–51.1]	29.4 [25.9–32.8]	1.54 [1.27–1.87]	362 [2.0%]	205 [1.2%]	51.1 [45.8–56.3]	30.8 [26.6–35.1]	1.64 [1.31–2.06]	120 [1.4%]	75 [1.0%]	37.7 [30.9–44.4]	26.0 [20.2–31.9]	1.30 [0.91–1.87]
10 to <20 years	407 [2.7%]	203 [1.5%]	55.8 [50.3–61.2]	30.6 [26.4–34.8]	1.82 [1.44–2.30]	307 [3.0%]	148 [1.6%]	63.2 [56.1–70.3]	32.7 [27.4–38.0]	1.92 [1.44–2.56]	100 [2.1%]	55 [1.3%]	40.9 [32.9–48.9]	25.9 [19.1–32.8]	1.66 [1.11–2.48]
≥20 years	51 [2.3%]	22 [1.1%]	48.7 [35.3–62.1]	22.5 [13.1–31.9]	2.60 [1.24–5.46]	39 [3.1%]	10 [0.8%]	67.6 [46.4–88.9]	17.0 [6.5–27.6]	5.77 [1.74–19.10]	12 [1.3%]	12 [1.5%]	25.5 [11.1–40.0]	30.7 [13.3–48.1]	1.03 [0.35–3.03]
≥1 year	1 446 [3.7%]	876 [2.4%]	45.6 [43.2–47.9]	29.7 [27.7–31.7]	1.42 [1.27–1.59]	1 090 [4.0%]	624 [2.4%]	50.5 [47.5–53.5]	30.7 [28.3–33.1]	1.53 [1.35–1.75]	356 [3.0%]	252 [2.2%]	35.1 [31.4–38.7]	27.5 [24.1–30.9]	1.19 [0.97–1.45]
Sex
Females	742 [3.3%]	552 [2.4%]	36.9 [34.2–39.5]	29.0 [26.6–31.4]	1.19 [1.04–1.37]	525 [3.4%]	373 [2.4%]	39.6 [36.2–43.0]	29.6 [26.6–32.6]	1.20 [1.01–1.41]	217 [2.9%]	179 [2.4%]	31.5 [27.3–35.7]	27.8 [23.8–31.9]	1.20 [0.95–1.51]
Males	906 [4.7%]	591 [3.1%]	58.0 [54.2–61.7]	41.2 [37.9–44.5]	1.26 [1.10–1.45]	716 [5.2%]	447 [3.3%]	64.4 [59.6–69.1]	42.9 [38.9–46.8]	1.41 [1.20–1.64]	190 [3.6%]	144 [2.7%]	42.2 [36.2–48.1]	36.8 [30.8–42.8]	0.89 [0.67–1.19]
Age
<18 years	2 [0.4%]	1 [0.2%]	4.5 [0.0–10.7]	2.7 [0.0–8.1]	—	2 [0.7%]	1 [0.4%]	7.7 [0.0–18.3]	4.5 [0.0–13.2]	6212.37 [0.00]	[0.0%]	[0.0%]	0.0 [0.0–0.0]	0.0 [0.0–0.0]	—
18 to <40 years	185 [1.5%]	91 [0.7%]	17.2 [14.7–19.7]	9.3 [7.4–11.2]	1.40 [1.02–1.92]	131 [1.6%]	62 [0.7%]	18.8 [15.5–22.0]	9.6 [7.2–12.0]	1.37 [0.93–2.04]	54 [1.3%]	29 [0.7%]	14.3 [10.5–18.1]	8.8 [5.6–12.0]	1.44 [0.84–2.47]
40 to <60 years	776 [5.0%]	504 [3.3%]	51.4 [47.8–55.0]	35.7 [32.6–38.9]	1.32 [1.14–1.52]	581 [5.4%]	351 [3.3%]	56.1 [51.5–60.6]	35.9 [32.1–39.6]	1.40 [1.18–1.67]	195 [4.2%]	153 [3.3%]	41.2 [35.4–47.0]	35.4 [29.8–41.0]	1.15 [0.89–1.48]
≥60 years	685 [5.1%]	547 [4.1%]	72.4 [67.0–77.8]	59.7 [54.7–64.6]	1.10 [0.95–1.28]	527 [5.5%]	406 [4.2%]	77.8 [71.2–84.5]	61.6 [55.6–67.6]	1.17 [0.99–1.39]	158 [4.2%]	141 [3.7%]	58.7 [49.5–67.8]	54.6 [45.6–63.6]	0.89 [0.65–1.20]
Year of IBD onset/index year
1969–1976	0	0	0.0 [0.0–0.0]	0.0 [0.0–0.0]	—	[0.0%]	[0.0%]	0.0 [0.0–0.0]	0.0 [0.0–0.0]	—	[0.0%]	[0.0%]	0.0 [0.0–0.0]	0.0 [0.0–0.0]	—
1977–1990	98 [5.8%]	77 [4.6%]	33.4 [26.8–40.0]	28.2 [21.9–34.5]	1.31 [0.88–1.95]	74 [6.9%]	59 [5.5%]	43.3 [33.4–53.2]	35.5 [26.4–44.5]	1.38 [0.86–2.20]	24 [3.9%]	18 [2.9%]	19.6 [11.8–27.5]	16.9 [9.1–24.7]	1.14 [0.52–2.50]
1991–2002	723 [6.6%]	518 [4.7%]	48.9 [45.4–52.5]	38.9 [35.5–42.2]	1.04 [0.89–1.21]	568 [7.3%]	370 [4.7%]	56.1 [51.5–60.8]	39.8 [35.7–43.9]	1.19 [0.99–1.43]	155 [4.8%]	148 [4.6%]	33.3 [28.0–38.5]	36.8 [30.9–42.7]	0.74 [0.56–0.99]
2003–2016	827 [2.8%]	548 [1.9%]	45.8 [42.7–48.9]	31.6 [29.0–34.2]	1.39 [1.22–1.58]	599 [3.0%]	391 [1.9%]	47.8 [43.9–51.6]	32.4 [29.2–35.6]	1.40 [1.20–1.63]	228 [2.5%]	157 [1.7%]	41.4 [36.0–46.8]	29.9 [25.2–34.5]	1.37 [1.07–1.74]
Year—First 5 years of follow-up
1969–1976	0	0	0.0 [0.0–0.0]	0.0 [0.0–0.0]	—	[0.0%]	[0.0%]	0.0 [0.0–0.0]	0.0 [0.0–0.0]	—	[0.0%]	[0.0%]	0.0 [0.0–0.0]	0.0 [0.0–0.0]	—
1977–1990	18 [1.1%]	28 [1.7%]	24.5 [13.2–35.9]	41.6 [26.2–57.0]	0.56 [0.27–1.15]	14 [1.3%]	25 [2.3%]	30.6 [14.6–46.7]	59.5 [36.2–82.8]	0.48 [0.21–1.09]	4 [0.7%]	3 [0.5%]	14.4 [0.3–28.6]	11.9 [0.0–25.3]	0.79 [0.13–4.84]
1991–2002	206 [1.9%]	251 [2.3%]	41.4 [35.7–47.0]	55.2 [48.4–62.0]	0.56 [0.44–0.72]	168 [2.2%]	174 [2.2%]	48.1 [40.9–55.4]	54.1 [46.0–62.1]	0.67 [0.50–0.90]	38 [1.2%]	77 [2.4%]	25.5 [17.4–33.6]	57.8 [44.9–70.7]	0.35 [0.20–0.59]
2003–2012	421 [2.0%]	359 [1.2%]	43.9 [39.7–48.1]	32.6 [29.2–35.9]	1.20 [1.01–1.43]	310 [2.1%]	258 [1.3%]	46.5 [41.3–51.7]	33.7 [29.6–37.9]	1.25 [1.02–1.53]	111 [1.8%]	101 [1.1%]	38.1 [31.0–45.1]	29.9 [24.1–35.8]	1.08 [0.78–1.50]
Country of birth
Nordic	1 537 [4.0%]	1 041 [2.7%]	45.7 [43.4–48.0]	33.3 [31.3–35.3]	1.22 [1.10–1.35]	1 166 [4.3%]	743 [2.8%]	50.7 [47.8–53.6]	34.5 [32.0–36.9]	1.32 [1.16–1.49]	371 [3.2%]	298 [2.5%]	34.9 [31.4–38.5]	30.7 [27.3–34.2]	1.01 [0.83–1.22]
Other	111 [3.6%]	102 [3.3%]	51.9 [42.3–61.6]	47.8 [38.5–57.0]	1.70 [0.59–4.92]	75 [3.8%]	77 [3.6%]	54.5 [42.2–66.9]	52.1 [40.5–63.8]	2.38 [0.70–8.13]	36 [3.3%]	25 [2.7%]	47.3 [31.8–62.7]	38.0 [23.1–52.9]	0.00 [0.00–.]
Montreal Classification CD
L1/L3/LX	—	—	—	—	—	—	—	—	—	—	214 [2.7%]	163 [2.1%]	38.3 [33.2–43.4]	31.5 [26.6–36.3]	1.13 [0.88–1.45]
L2	—	—	—	—	—	—	—	—	—	—	88 [3.4%]	63 [2.5%]	43.9 [34.7–53.1]	34.0 [25.6–42.4]	1.27 [0.86–1.87]
Montreal Classification UC
E1/E2	—	—	—	—	—	338 [2.9%]	244 [2.1%]	41.7 [37.2–46.1]	32.5 [28.4–36.5]	1.24 [1.01–1.53]	—	—	—	—	—
E3/EX	—	—	—	—	—	616 [4.1%]	386 [2.6%]	53.8 [49.5–58.0]	35.4 [31.8–38.9]	1.39 [1.18–1.65]	—	—	—	—	—
Extraintestinal manifestations
PSC	23 [6.4%]	10 [2.8%]	102.1 [60.4–143.8]	41.0 [15.6–66.4]	1.90 [0.71–5.05]	23 [7.7%]	10 [3.4%]	120.1 [71.0–169.2]	49.5 [18.8–80.3]	1.90 [0.71–5.05]	[0.0%]	[0.0%]	0.0 [0.0–0.0]	0.0 [0.0–0.0]	—
Other EMF	89 [3.3%]	53 [2.0%]	55.3 [43.8–66.8]	33.5 [24.5–42.5]	1.29 [0.85–1.97]	70 [4.3%]	37 [2.3%]	70.3 [53.8–86.7]	37.3 [25.3–49.3]	1.41 [0.84–2.37]	19 [1.8%]	16 [1.5%]	31.1 [17.1–45.0]	27.2 [13.9–40.5]	1.09 [0.53–2.24]
Inflammatory status at index
Low histology	208 [4.0%]	123 [2.4%]	47.5 [41.0–53.9]	30.5 [25.1–35.9]	1.25 [0.94–1.66]	155 [4.8%]	92 [2.9%]	54.7 [46.1–63.3]	34.8 [27.7–42.0]	1.32 [0.95–1.83]	53 [2.7%]	31 [1.6%]	34.2 [25.0–43.4]	22.3 [14.4–30.1]	0.98 [0.53–1.80]
High histology	1 440 [3.9%]	1 020 [2.8%]	45.9 [43.5–48.3]	34.7 [32.6–36.9]	1.23 [1.11–1.36]	1 086 [4.2%]	728 [2.8%]	50.4 [47.4–53.4]	35.7 [33.1–38.3]	1.31 [1.16–1.48]	354 [3.3%]	292 [2.7%]	36.0 [32.2–39.7]	32.6 [28.9–36.3]	1.07 [0.88–1.29]
Colon surgery at baseline
Resection of the colon	72 [2.9%]	96 [3.9%]	24.3 [18.7–29.9]	37.6 [30.1–45.2]	0.52 [0.35–0.77]	9 [2.0%]	20 [4.4%]	25.2 [8.8–41.7]	57.8 [32.5–83.1]	0.54 [0.20–1.51]	63 [3.1%]	76 [3.7%]	24.2 [18.2–30.2]	34.5 [26.7–42.2]	0.51 [0.33–0.78]
Other bowel surgery	25 [2.5%]	29 [2.9%]	29.8 [18.1–41.5]	36.8 [23.4–50.2]	1.17 [0.52–2.63]	16 [3.4%]	16 [3.4%]	46.2 [23.6–68.9]	47.0 [24.0–70.1]	9.85 [1.51–64.23]	9 [1.6%]	13 [2.4%]	18.3 [6.3–30.2]	29.0 [13.3–44.8]	0.25 [0.05–1.22]

^aAdjusted for age, sex, calendar period and number of endoscopies at baseline.