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

Table 4 Multivariable 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	3.42 (2.40-4.86)	< 0.001	1.85 (1.22-7.80)	0.004
> 70	6.19 (4.02-9.54)	< 0.001	2.56 (1.45-4.52)	0.001
BMI (kg/m2)
< 25	1 (ref)		1 (ref)
25-29.9	1.25 (0.90-1.73)	0.18	1.46 (0.92-2.32)	0.11
≥ 30	2.06 (1.46-2.91)	< 0.001	2.58 (1.53-4.34)	< 0.001
Hard physical activity (h/wk)
< 1	1 (ref)		1 (ref)
≥ 1	0.67 (0.39-1.15)	0.15	1.03 (0.67-1.57)	0.90
Smoking cigarettes
Never daily	1 (ref)		1 (ref)
Formerly	1.65 (1.15-2.36)	0.007	1.45 (0.91-2.31)	0.12
Present daily	2.11 (1.51-2.94)	< 0.001	1.38 (0.84-2.29)	0.21
Problems with breathlessness the last 12 mo
Not at all	1 (ref)		1 (ref)
Slightly	1.12 (0.68-1.86)	0.66	2.57 (1.55-4.28)	< 0.001
Very much	1.43 (0.45-4.59)	0.55	2.48 (0.74-8.39)	0.14
Problems with constipation the last 12 mo
Not at all	1 (ref)		1 (ref)
Slightly	1.05 (0.75-1.48)	0.77	0.94 (0.53-1.66)	0.82
Very much	1.54 (0.95-2.49)	0.078	1.41 (0.43-4.68)	0.57
Type of bread
Only fine	1 (ref)		1 (ref)
Mixed	1.08 (0.65-1.79)	0.77	1.06 (0.58-1.93)	0.85
Only coarse	0.93 (0.62-1.41)	0.74	1.24 (0.74-2.07)	0.41
Highest educational level
Primary school	1 (ref)		1 (ref)
Higher than primary school	1.13 (0.82-1.54)	0.46	0.90 (0.61-1.33)	0.60
Living area
Urban	1 (ref)		1 (ref)
Rural	0.92 (0.65-1.30)	0.63	1.80 (1.21-2.67)	0.004