Table 6 Results of ordinal regression analysis for the number of risk alleles associated with Crohn’s disease, depicting whether an increasing number of risk alleles is associated with specific disease characteristics

Characteristic	All (n = 1353)	Follow-up >5 years (n = 1072)	Follow-up >10 years n = 763
Age at diagnosis <40 years	0.048	0.06	0.58
Familial occurrence	0.12	0.03	0.69
Stricturing and/or penetrating behaviour	0.001	0.006	0.052
Perianal disease	0.57	0.60	0.67
Operation	0.03	0.07	0.13
Extra-intestinal manifestations	0.17	0.42	0.85

Values in bold type are statistically significant with a p value <0.05.
The risk alleles were: NOD2, the presence of one of the R702W, G908R or 3020insC polymorphisms was defined as one risk allele; IBD5, the rs2522027*C allele; ATG16L1, the rs2241880*G allele; DLG5, the rs2289310*C allele; the risk “allele” for IL23R is defined as homozygosity for rs11209026*G.
ATG16L1, autophagy-related 16-like 1 gene; DLG5, Drosophila discs large homologue 5 gene; IBD5, inflammatory bowel disease 5 gene; IL23R, interleukin 23 receptor gene; NOD2, nucleotide-binding and oligomerisation domain 2 gene.