Table I. Clinical characteristics and anti-HBs levels of subjects stratified by humoral immune response to primary series of HBV vaccine at age 1 and 2 y
Clinical CharacteristicsHigh- Responders at 1 y (n = 57)Low- Responders at 1 y (n = 16)p ValueHigh-Responders at 2 y (n = 29)Low-Responders at 2 y (n = 28)Nonresponders at 2 y (n = 15)p Value
Sex, n (%)0.614a0.330a
 Male29 (50.8)7 (43.8)14 (48.3)16 (57.1)5 (33.3)
 Female28 (49.2)9 (56.2)15 (51.7)12 (42.9)10 (66.4)
Ethnicity, n (%)b0.649a0.376a
 Caucasian23 (40.3)9 (56.2)11 (40)16 (57.1)8 (53.3)
 Asian6 (10.5)3 (18.7)5 (17.2)1 (3.4)3 (20)
 South Asian8 (14)1 (6.2)4 (13.8)4 (14.3)2 (13.3)
 Asian-Caucasian5 (8.8)1 (16.6)4 (13.8)2 (7.1)0 (0)
Anti-HBs IgG (IU/l) (GMC, 95% CI)340.24 (275.42–407.38)57.37 (44.66–72.44)0.000c231.64 (186.20–281.83)36.03 (27.52–45.70)1.73 (1.17–2.51)0.000d
  • Nonresponders: anti-HBs levels <10 IU/l; low-responders: anti-HBs levels 10–100 IU/l; high-responders: anti-HBs levels ≥100 IU/l. Categorical data are presented as a number (%).

  • a Pearson Chi-Square test.

  • b 17 cases with missing data.

  • c Mann–Whitney U test.

  • d Kruskal–Wallis test.

  • CI, confidence interval; GMC, geometric mean concentration.