From: Can temperature explain the latitudinal gradient of ulcerative colitis? Cohort of Norway
Variable | Comment | References | Present study |
---|---|---|---|
Age, sex | More men than women, 25–35 years | Moum [56] | Included |
Smoking | Protective (OR: 0.58) | Mahid [11] | Included |
Appendectomy | Protective | Lopez [13] | Not included |
Diet | Red meat, n-6 fatty acids, sweets increase risk n-3 fatty acids, fruits, vegetables decrease risk | Ng [58] (references therein) | Not included |
Breast-feeding | Protecting | Klement [12] | Not included |
Acute gastrointestinal infections | Risk factor. Campylobacter, Salmonella | Gradel [59] | Not included |
Sun-exposure | Not investigated | - | Not included |
Sosio-economy | Higher in urban, urban/rural change | Aamodt [19] | Included |