Background/Purpose:

Kawasaki disease (KD) is an autoimmune disease involving primarily medium-sized vessels and is the leading cause of acquired cardiac disease in children. The pathogenesis is still unknown and the evidence for familial aggregation in Kawasaki disease is rare. The aims of this study was to estimate sibling relative risk (RR) and heritability of KD.

Methods:

Using data from the National Health Insurance Research Database in Taiwan, we conducted a nationwide cross-sectional study of 2,683,174 males and 2,483,901 females who were younger than 20 years in 2010. KD was defined as children < 20 years of age hospitalised with a primary or secondary diagnosis of KD between 1996 and 2010. We identified individuals with a full sibling affected by KD and compared the prevalence of the disease between individuals with and without an affected sibling. The identification of sibling of each individual was determined using the NIHRD registry for beneficiaries, which specifies relationships between the insured person who paid the insurance fee and his/her dependents and allows first-degree relatives (father, mother, son, daughter, brother, sister, twin) to be identified directly. Full siblings were identified as individuals who shared the same parents. The marginal Cox proportional hazard model with an equal follow-up time for all subjects was used to estimate RR and the 95% confidence interval (CI). This model was used to account for shared environment and case clustering within families with robust variance, and to adjust for age, place of residence, income levels and occupation. The RR was estimated for different first-degree relative categories and for the number of first-degree relatives affected by gout. Heritability (h2) was estimated using the multifactorial polygenic model. 

Results:

There were 7,443 male and 4,558 female individuals who had KD between 1996 and 2010. Individuals with an affected sibling with KD had a higher prevalence of KD (1.53%) than those without (0.23%). The risk of KD in individuals with an affected sibling was 6.39 (95% CI, 4.63–8.83) times greater than that in individuals without an affect sibling. The sibling RR (95% CI) was slightly higher among female individuals with affected siblings (6.79, 4.50–10.27) than male ones (6.11, 4.19–8.90). The heritability of KD was 0.45 (95% CI, 0.36–0.55).

Conclusion:

The present study provides population-based estimate for sibling RR and demonstrates familial aggregation of KD. The results suggest a significant genetic contribution to the KD susceptibility.

---

« Back to 2012 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/sibling-relative-risk-and-heritability-of-kawasaki-disease-a-nationwide-population-study-in-taiwan/