Public Release Type:
Journal
Publication Year: 2014
Authors:
Cloonan YK,
Johnson G,
Ling SC,
Murray KF,
Rodriguez-Baez N,
Rosenthal P,
Schwarzenberg SJ,
Schwarz KB,
Teckman J
Studies:
Hepatitis B Research Network
Aims (1) To describe characteristics of adopted children with CHB compared to children living with their birth parents (“not-adopted”). (2) To determine if adoption status is associated with differences in CHB disease phenotype, suggesting the importance of early environmental influences on later disease course. Methods We analyzed baseline data from children enrolled in the HBRN pediatric cohort study at 7 sites in N. America. Stepwise logistic regression was used to investigate associations with investigator-assigned CHB disease phenotype. Results Of 335 children, 187 were adopted at median age 27m (IQR 14-62m) after birth in Asia (n=132, 73%), Europe (24, 13%) or Africa (15, 8%). In univariate analysis compared to not-adopted, adopted were younger (median 9.7 v 12.3y), less likely to be Asian (74% v 83%), more likely to be female (75% v 45%) and immigrants to North America (97% v 48%), with parents with higher education and employed mothers, & to have been treated for HBV (18% v 8%). Adopted had lower height (median percentile 30th v 56th) and BMI (47th v 66th). HBV genotype B was most common in adopted (B=49%, C=26%, Other=25%) v not-adopted (36%, 40%, 24%). HBeAg+ (76% vs 72%), anti-HBe+ (29% v 29%) and HBV DNA viral load (8.2 vs 8.1 log10 IU/ml) were similar, but ALT was lower in adopted (35 IQR 23-47, v 42 IQR 30-59 IU/l). Adopted were more likely to be immune-tolerant (IT) (51% v 30%). After controlling for genotype in a multivariable model, adoption & ht-for-age were associated with CHB phenotype. The association with height held true when only Asian children were included in analysis, but dropped out when treated children were excluded. Conclusion IT disease phenotype is associated with adoption status independent of viral genotype and host variables (e.g. age, sex, race). Future studies should further investigate the influence of environmental factors on the course of CHB infection.