The following is a summary of “Spondyloarthritis in First-Degree Relatives and Spouses of Patients with Inflammatory Bowel Disease: A Nationwide Population-based Cohort Study from Sweden,” published in the March 2024 issue of Gastroenterology by Shrestha et al.
A link between inflammatory bowel disease [IBD] and spondyloarthritis [SpA] is suspected due to overlapping risk factors, but the genetic and environmental underpinnings remain unclear.
Researchers conducted a retrospective study to compare the risk of SpA in first-degree relatives (FDRs) and spouses of IBD patients with FDRs and spouses from a matched control group.
They examined 147,080 FDRs and 25,945 spouses of patients diagnosed with incident IBD, N = 39,203 (between 2006 and 2016), along with 1,453,429 FDRs and 258,098 spouses of matched reference individuals, N = 390,490, using nationwide Swedish registers and gastrointestinal biopsy data. Participants were tracked from 1987 to 2017, and estimated HRs of SpA were estimated using Cox regression analysis.
The results showed a follow-up period, 2,430 FDRs of IBD patients [6.5 per 10,000 person-years] and 17,761 FDRs of reference individuals [4.8 per 10,000 person-years] were diagnosed with SpA, yielding an HR of 1.35 [95%CI: 1.29, 1.41]. Subgroup analyses revealed a higher SpA risk among FDRs of Crohn’s disease patients [HR = 1.44; 95% CI: 1.34, 1.56] and FDRs of IBD patients diagnosed at age <18 years [HR = 1.46; 95% CI: 1.27, 1.68]. Spouses of IBD patients also had an elevated SpA rate compared to spouses of reference individuals [4.3 vs. 3.5 per 10,000 person-years; HR = 1.22; 95% CI: 1.09, 1.37], although the difference was less pronounced. No specific risk pattern among spouses was identified in subgroup analyses.
Investigators concluded that the shared familial risk of IBD and SpA pointed to common genetic factors, although environmental influences or shared healthcare behaviors in spouses couldn’t be ruled out.
Source: academic.oup.com/ecco-jcc/advance-article/doi/10.1093/ecco-jcc/jjae041/7633748
