Table 1.

Characteristics of IBD cases and matched population controls at date of diagnosis or indexing.

Clinical or demographic feature	CD cases [n = 7637]	CD-matched controls [n = 76 370]	pdifference	UC cases [n = 15 652]	UC-matched Controls [n = 156 520]	pdifference
Average age at diagnosis/indexing,a years [SD]	44.3 [18.8]	44.3 [18.8]	>0.99	46.0 [18.6]	46.0 [18.6]	0.99
Median month and year of diagnosis/indexing [range]	8/2010 [1/2006 - 12/2014]		-	4/2010 [1/2006 - 12/2014]		-
Sexa [%]						>0.99
Male	3685 [48]	36850 [48]	>0.99	8129 [52]	81290 [52]
Female	3952 [52]	39520 [52]		7523 [48]	75230 [48]
Regiona [%]						>0.99
Stockholm-Gotland	1856 [24]	18560 [24]		2944 [19]	29440 [19]
Uppsala-Örebro	1524 [20]	15240 [20]		3512 [22]	35120 [22]
Södra [south]	1683 [22]	16830 [22]	>0.99	3135 [20]	31350 [20]
Sydöstra [south-east]	1015 [13]	10150 [13]		1771 [11]	17710 [11]
Västra [west]	963 [13]	9630 [13]		2996 [19]	29960 [19]
Norra [north]	596 [7.8]	5960 [7.8]		1294 [8.3]	12940 [8.3]
Years in full-time education [%]						0.15
≤9	1540 [20]	14155 [19]	<0.001	2912 [19]	29896 [19]
10–12	3647 [48]	35512 [47]		7280 [47]	71645 [46]
>12	2450 [32]	26703 [35]		5460 [35]	54979 [35]
Dyslipidaemiab [%]	208 [2.7]	1789 [2.3]	0.037	463 [3.0]	3751 [2.3]	<0.001
Hypertension [%]	1767 [23]	14390 [19]	<0.001	3490 [22]	31364 [20]	<0.001
Ischaemic heart disease [%]	352 [4.6]	2831 [3.7]	<0.001	768 [4.9]	6657 [4.3]	<0.001
Stroke [%]	196 [2.6]	1581 [2.1]	0.004	367 [2.3]	3526 [2.3]	0.46
Other arterial diseases [%]	217 [2.3]	1671 [2.2]	<0.001	438 [2.8]	3578 [2.3]	<0.001
Heart failure [%]	157 [2.1]	1009 [1.3]	<0.001	301 [1.9]	2552 [1.6]	0.006
Type 2 diabetes [%]	328 [4.3]	2913 [3.8]	0.038	669 [4.3]	6320 [4.0]	0.15
Chronic obstructive pulmonary disease [%]	182 [2.4]	907 [1.2]	<0.001	296 [1.8]	1881 [1.2]	<0.001
Type 1 diabetes [%]	27 [0.4]	359 [0.5]	0.15	73 [0.5]	772 [0.5]	0.65
Any previous use of prescribed NSAIDs [%]	1687 [22]	11617 [15]	<0.001	2861 [18]	23129 [15]	<0.001
Any previous oral contraceptive use among women [%]	1038 [26]	8869 [22]	<0.001	1829 [24]	15718 [21]	<0.001
Average number of outpatient and inpatient encounters over previous year [SD]c	2.4 [5.4]	1.1 [2.7]	<0.001	1.6 [4.0]	1.1 [3.1]	<0.001
Any statin use before diagnosis/indexing [%]	620 [8.1]	6421 [8.4]	0.38	1552 [9.9]	14042 [9.0]	<0.001
Statin use in 12 months before diagnosis/indexing [%]	519 [6.8]	5642 [7.4]	0.059	1344 [8.6]	12376 [7.9]	0.003
Average cumulative statin dose among statin users, DDDd [SD]	1135 [1184]	1163 [1257]	0.039	1078 [1155]	1112 [1205]	0.09

Percentages for categorical variables may not sum to 100 due to rounding.

SD, standard deviation; NSAID, non-steroidal anti-inflammatory drug.

^aMatching factor.

^bAscertained using diagnostic entries in outpatient and inpatient registers only.

^‡cTotal encounters between 18 and 6 months before diagnosis as case or indexing as a control.

^dWHO Defined Daily Dose