Association of irritable bowel syndrome and venous thromboembolism

Figures & data

Table 1. Characteristics for cases with venous thromboembolism (VTE) and controls from the total population register (TPR) matched 1:5 based on age, sex, country of birth, and educational levels.

	Controls from TPR (n = 452,510)	VTE cases (n = 90,502)	Difference (p value)
Males (%)	49.6	49.6	–
Born in Sweden (%)	87.9	87.9	–
Mean year of birth	1946	1946	–
Education level	1.90	1.90	–
Atrial fibrillation prior to VTE	2.82%	3.70%	<.0001
Alcoholism prior to VTE	1.30%	2.02%	<.0001
COPD prior to VTE	2.05%	4.25%	<.0001
Diabetes prior to VTE	3.04%	3.88%	<.0001
Heart failure prior to VTE	1.37%	2.46%	<.0001
Hyperlipidaemia prior to VTE	0.22%	0.23%	.6544
Hypertension prior to VTE	2.27%	3.15%	<.0001
Obesity prior to VTE	0.34%	0.96%	<.0001
Cancer	7.17%	19.38%	<.0001
Fractures or trauma	0.91%	5.69%	<.0001
Pregnancy or childbirth	0.56%	1.67%	<.0001
Surgery	1.51%	13.47%	<.0001
VTE Parent (during 2001–2010)	1.82%	3.38%	<.0001

Table 2. Characteristics and results from the case-control study of the association between IBS (specialist treated outpatients) and VTE (hospital diagnosed patients) in the Swedish population.

	VTE cases	Controls
Number (N)	90,502	452,510
Mean age at VTE	60.1 (14.8)
Age range	18–80
			Odds ratio
Prior IBS	458 (0.51%)	1405 (0.31%)	1.64 (1.47; 1.82)
0–90 days	28 (0.03%)	66 (0.01%)	2.12 (1.36; 3.30)
91–365 days	77 (0.09%)	175 (0.04%)	2.21 (1.69; 2.89)
≥365 days	354 (0.39%)	1167 (0.26%)	1.52 (1.35; 1.71)
Additional analysis
Prior IBS^a	399 (0.44%)	1306 (0.29%)	1.53 (1.37; 1.72)
Prior IBS^b			1.49 (1.33; 1.67)
Interaction with Age at VTE	p: .009
Age 50	1.79 (1.58; 2.02)
Age 60	1.64 (1.46; 1.81)
Age 70	1.49 (1.30; 1.69)
Age 80	1.35 (1.13; 1.62)
Interaction with gender	p: .946

^aExcluding colorectal cancer, coeliac disease and inflammatory bowel disease (IBD).

^bAdjusted for atrial fibrillation, alcoholism, COPD, diabetes, heart failure, hyperlipidaemia, hypertension, obesity, cancer any time before and within three months after VTE, fractures or trauma 90 days before VTE, pregnancy (and abortion) within 90 days before or childbirth 90 days before and within six months after index date, hospitalised surgery (90 days before).

Table 3. Results from the case-control study (specialist outpatients) of the association between risk factors and VTE showing how an adjustment with respective risk factor affects OR of VTE in IBS patients in the Swedish population.

	Odds ratio for VTE for adjusting variables (univariate models)	Odds ratio for IBS (bivariate models including respective risk factor and IBS)
Atrial fibrillation prior to VTE	1.33 (1.28; 1.39)	1.63 (1.46; 1.81)
Alcoholism prior to VTE	1.57 (1.49; 1.66)	1.64 (1.47; 1.82)
COPD prior to VTE	2.13 (2.05; 2.21)	1.58 (1.42; 1.76)
Diabetes prior to VTE	1.29 (1.24; 1.34)	1.63 (1.47; 1.82)
Heart failure prior to VTE	1.85 (1.76; 1.94)	1.64 (1.47; 1.82)
Hyperlipidaemia prior to VTE	1.03 (0.89; 1.20)	1.64 (1.47; 1.82)
Hypertension prior to VTE	1.41 (1.35; 1.47)	1.62 (1.46; 1.81)
Obesity prior to VTE	2.81 (2.58; 3.05)	1.62 (1.45; 1.80)
Cancer	3.33 (3.26; 3.40)	1.63 (1.47; 1.82)
Fractures or trauma	6.57 (6.30; 6.85)	1.62 (1.46; 1.81)
Pregnancy or childbirth	3.62 (3.37; 3.89)	1.63 (1.47; 1.81)
Surgery	10.27 (9.95; 10.60)	1.57 (1.40; 1.75)
		Multivariate odds ratio for IBS
All (multivariate model)		1.49 (1.33; 1.67)

Table 4. Results from the case-control study of the association between IBS and VTE in a Swedish primary health care population.

	VTE cases	Controls
N	9766	48,830
Mean age at VTE	57.3 (15.4)
Age range	18–80
Males	47.2%
OR in Primary Health Care patients			Odds ratio
Prior IBS	95 (0.97%)	404 (0.83%)	1.18 (0.94; 1.48)
0–90 days	1 (0.01%)	20 (0.04%)
91–365 days	12 (0.12%)	41 (0.08%)	1.46 (0.77; 2.78)
≥365 days	82 (0.84%)	343 (0.70%)	1.20 (0.94; 1.53)
Interaction with age at VTE	p: .0722
Interaction with gender	p: .182

Data availability

No additional data available due to Swedish regulation. However, the nationwide registers used in the present study are maintained by Statistics Sweden and the National Board of Health and Welfare.