Hepatitis B immune status in adolescents vaccinated during infancy: A retrospective cohort study from a pediatric practice in Germany

Figures & data

Figure 1. Participant flowchart.

Table 1. Characteristics of study participants (n = 106).

Characteristics at baseline (N = 87–106)	n or median (% or range)
Male gender	56 (53)
Gestational age (weeks)	40 (33–42)
Full-term pregnancy^1	77 (89)
Birth weight (g)	3460 (1890–4670)
Received 3-doses vaccination course	96 (91)
Received 4-doses vaccination course	10 (9)
Vaccine type used for infant vaccination
- monovalent vaccine	68 (64)
- hexavalent vaccine	13 (12)
- unknown	25 (24)
Age (weeks) at vaccination
- first dose	30 (1–53)
- second dose	36 (4–86)
- third dose	84 (20–122)
- fourth dose	85 (47–104)
Average time between first and third dose (weeks)	52 (12–95)
Average time between second and third dose (weeks)	43 (5–90)
Characteristics at follow-up (N=84–106)
Age at follow-up blood sample (years)	13.6 (10.4–16.5)
Chronic diseases^2	45 (52)
Body mass index (kg/m^2)	19.5 (15–30)

¹ defined as gestational age >37 weeks

² includes: endocrine and metabolic, neuropsychiatric, respiratory, orthopedic, hematologic and cardiovascular diseases, congenital malformations.

Table 2. Associations between participant characteristics and pre-booster anti-HBs levels (n = 106).

	Pre-booster anti-HBs at follow up (IU/l)
	<10(n = 42)	10–99 (n = 49)	≥100(n = 15)
Characteristics at baseline				p^1
Male (gender)	27 (64)	20 (41)	9 (60)	0.07
Gestational week	40 (33–42)	40 (33–42)	39 (34–42)	0.51
Full-term pregnancy	32 (91)	33 (89)	12 (80)	0.50
Birth weight (g)	3490 (2070–4670)	3450 (1990–4370)	3600 (1890–4400)	0.87
Received 4-doses vaccination course	2 (5)	8 (16)	0 (0)	0.1
Vaccine type used at baseline				0.06
- monovalent vaccine	27 (64)	29 (59)	12 (80)
- hexavalent vaccine	1 (2)	9 (18)	3 (20)
- unknown, n (%)	14 (33)	11 (22)	0 (0)
Age (weeks) at
- first vaccination	32 (1–52)	29 (6–52)	30 (13–52)	0.48
- second vaccination	38.5 (4–61)	35 (12–86)	34 (17–69)	0.33
- third vaccination	85.5 (26–116)	82 (20–122)	90 (30–120)	0.47
Time between first and third dose (weeks)	51 (13–86)	51 (12–89)	60 (17–94)	0.41
Time between second and third dose (weeks)	43 (8–82)	43 (4–85)	52 (13–90)	0.25
Characteristics at follow-up
Age at follow-up blood sample (months)	165	164	165	0.94
Chronic illness				0.2
- none	21 (54)	21 (51)	0
- endocrine and metabolic diseases	2 (5)	6 (15)	2 (29)
- neuropsychiatric diseases	2 (5)	1 (2)	0
- respiratory diseases	9 (23)	10 (24)	4 (57)
- congenital malformations	2 (5)	0	0
- orthopedic diseases	1 (3)	0	0
- haemotologic diseases	1 (3)	3 (7)	1 (14)
- cardiovascular diseases	1 (3)	0	0
Body mass index (kg/m)^2	20 (17–25)	19 (15–27)	19.5 (17–30)	0.14

Numbers are n (&) or median (range)

¹ Kruskal-Wallis test or chi-square test, as appropriate.

Table 3. Association between pre-booster and post-booster anti-HBs levels (p = 0.045 by Fishers exact test; n = 34).

Post-booster anti-HBs level	Pre-booster anti-HBs <10 IU/l	Pre-booster anti-HBs 10–99 IU/l
<10 IU/l	—	—
10–99 IU/l	1	0
100–999 IU/l	12	2
≥ 1000 IU/l	9	10