Published online Apr 14, 2021. doi: 10.3748/wjg.v27.i14.1483
Peer-review started: September 18, 2020
First decision: November 3, 2020
Revised: November 17, 2020
Accepted: February 25, 2021
Article in press: February 25, 2021
Published online: April 14, 2021
Apolipoprotein E (APOE) polymorphisms were previously reported to be linked with the risk of developing inflammatory bowel diseases (IBD).
No data on the relationship between APOE polymorphisms and disease severity are available.
This study aimed to investigate the link between APOE variants and disease severity in IBD.
The TaqMan hydrolysis probe assay was used to genotype 406 patients with IBD (192 had ulcerative colitis and 214 had Crohn’s disease). Clinical expression involved disease activity scales, albumin and C-reactive protein levels, disease localisation and behaviour, and treatment with the time and age of the first intervention. The number of hospitalisations and days spent in hospital due to exacerbation as well as the number of relapses and severe relapses were also estimated.
Ulcerative colitis patients with the APOEε4 allele had the lowest C-reactive protein values both at diagnosis (P = 0.0435) and the worst flare (P = 0.0013) compared to patients with the APOEε2 allele and genotype APOEε3/ε3. Crohn’s disease patients with the APOEε2 allele scored lower on the Pediatric Crohn’s Disease Activity Index at diagnosis (P = 0.0204). All IBD patients with the APOEε2 allele spent fewer days in the hospital due to relapse (P = 0.0440).
The APOE genotype seems to be associated with some indices of disease course such as inflammatory markers, disease activity, and applied treatment. However, the clinical significance of the differences identified remains modest.
Further mechanistic studies of APOE action in IBD are warranted.