Risk factors of admission for acute colonic diverticulitis in a population-based cohort study: The North Trondelag Health Study, Norway

Table 3 Univariable Cox regression analysis of risk factors relating to admission for acute diverticulitis, after multiple imputation for missing values

Characteristic	Females		Males
	HR (95%CI)	P value	HR (95%CI)	P value
Age in years (yr)
< 50	1 (ref)		1 (ref)
50-70	3.55 (2.58-4.89)	< 0.001	2.36 (1.60- 3.48)	< 0.001
> 70	5.88 (4.10-8.44)	< 0.001	3.46 (2.06-5.79)	< 0.001
BMI (kg/m2)
< 25	1 (ref)		1 (ref)
25-29.9	1.59 (1.16-2.18)	0.004	1.62 (1.03-2.56)	0.040
≥ 30	2.86 (2.06-3.97)	< 0.001	3.20 (1.93-5.31)	< 0.001
Hard physical activity (h/wk)
< 1	1 (ref)		1 (ref)
≥ 1	0.46 (0.27- 0.77)	0.003	0.85 (0.56-1.29)	0.45
Smoking cigarettes
Never daily	1 (ref)		1 (ref)
Formerly	1.45 (1.04-2.01)	0.027	2.12 (1.36- 3.13)	0.001
Present daily	1.36 (1.01-1.83)	0.043	1.49 (0.91- 2.44)	0.11
Problems with breathlessness the last 12 mo
Not at all	1 (ref)		1 (ref)
Slightly	1.44 (0.87-2.36)	0.15	3.09 (1.88- 5.08)	< 0.001
Very much	2.32 (0.76- 7.12)	0.14	3.54 (1.13-11.2)	0.031
Problems with constipation the last 12 mo
Not at all	1 (ref)		1 (ref)
Slightly	1.14 (0.82-1.60)	0.44	1.25 (0.72-1.19)	0.43
Very much	2.02 (1.29-3.18)	0.002	2.35 (0.76-7.24)	0.14
Type of bread
Only fine	1 (ref)		1 (ref)
Mixed	0.97 (0.58-1.61)	0.90	1.03 (0.57-1.86)	0.93
Only coarse	1.01 (0.67-1.51)	0.96	1.26 (0.76-1.08)	0.38
Highest educational level
Primary school	1 (ref)		1 (ref)
Higher than primary school	0.49 (0.37-0.64)	< 0.001	0.57 (0.39-0.82)	0.002
Living area
Urban	1 (ref)		1 (ref)
Rural	0.92 (0.65-1.30)	0.63	1.80 (1.21-2.67)	0.004

BMI: Body mass index.