Crohn’s disease environmental factors in the developing world: A case-control study in a statewide catchment area in Brazil

Table 3 Multiple linear regression to assess independent factors associated with the development of Crohn’s disease

Characteristics	Multivariate analysis 1			Multivariate analysis 2
	1ORaj	95%CI	P value	1ORaj	95%CI	P value
Sex
Male	2.08	1.18-3.68	0.011	2.09	1.22-3.59	0.007
Female	1.00			1.00
Age (yr)
18-39	2.83	1.51-5.32	0.001	3.10	1.71-5.63	< 0.001
40-80	1.00			1.00
Race
White	2.30	1.31-4.02	0.004	2.32	1.36-3.97	0.002
Non-white	1.00			1.00
Educational level
Elementary	1.00
High school	1.44	0.75-2.75	0.266
Graduate school	1.45	0.52-4.04	0.470
Family income1
< 3	1.00
3-5	0.83	0.42-1.64	0.609
> 5	0.90	0.40-2.00	0.807
No information	1.74	0.67-4.51	0.254
Rural area
No	1.32	0.65-2.68	0.432
Yes	1.00
Housing conditions
Inadequate	1.36	0.49-3.79	0.548
Adequate	1.00
Family size in adulthood (n)
Until 1	1.00			1.00
2-3	3.26	1.59-6.68	0.001	3.02	1.52-5.99	0.002
4-8	3.16	1.36-7.34	0.007	2.87	1.26-6.50	0.012
Family size in childhood (n)
1-3	1.28	0.57-2.84	0.541	1.66	0.81-3.40	0.159
4-6	2.08	1.06-4.08	0.032	2.34	1.27-4.32	0.006
> 7	1.00			1.00
Pets
No	1.45	0.69-3.05	0.323
Yes	1.00
Breastfeeding
No	1.00
Yes	0.77	0.28-2.09	0.616
Unknown	0.48	0.12-1.89	0.296
Exposure to untreated water
No	1.00
Yes	1.54	0.80-2.93	0.188
Vaccine (childhood)
No	1.00
Yes	0.57	0.20-1.58	0.284
Viral diseases (childhood)
No	2.42	0.90-6.48	0.078	2.23	0.88-5.62	0.088
Yes	1.00			1.00
Helmintic infections
No	0.91	0.51-1.65	0.776
Yes	1.00
Exposure to enteric pathogens
No	1.00			1.00
Yes	2.89	1.62-5.17	< 0.001	2.23	1.41-4.10	0.001
Previous appendectomy
No	1.00			1.00
Yes	2.71	0.93-7.83	0.065	2.47	0.89-6.83	0.080
Tobacco exposure
Never	1.00			1.00
Prior	3.13	1.57-6.26	0.001	2.83	1.46-5.47	0.002
Current	1.13	0.50-2.54	0.768	1.12	0.51-2.44	0.775
Family history
No	1.00
Yes	1.27	0.45-3.53	0.644

¹OR_aj = Odd Ratio adjusted. In the final model only the variables included were statistically significant (95%CI not including value 1). P value Hosmer-Lemeshow statistic for setting the final model = 0.406.