Relationship between serum b2-microglobulin levels and virological breakthrough in HBeAg-negative chronic hepatitis B patients, under long-term treatment schedules including lamivudine

Table 1 Demographic, biochemical, virological and histological features at baseline, for both groups of CHB patients.

	Group A (n = 25)	Group B (n = 12)	P
Age (yr)	42.8±13.6	40.8±10.4	0.49
ALT (IU/L)	218±106.1	134.6±92.9	0.07
HBV-DNA -log10 (copies/mL)	5.96±0.86	6.27±0.76	0.29
Grade (0–18)	7.0±3.3	5.6±1.8	0.12
Stage (0–6)	3.2±1.5	2.9±1.2	0.54
Cirrhosis (%)	3/25 (12)	2/12 (16.6)	0.71
B2m (mg/dL) (baseline levels)	1695.5±348.1	1787.1±367.2	0.25
Duration of b2m elevation (mo)	5.3±3.5	5.0±1.47	0.82
B2m elevation in 3 mo (%)	17/25 (68)	12/12 (100)	0.03a

ALT: alanine aminotransferase. B2m: b2-microglobilin.

^aP<0.05 vs other group.

Table 2 Demographic, biochemical, virological and histological features at baseline, for the subgroups of patients who did (subgroup A1) and did not (subgroup A2) exhibit virological breakthrough (VB) during long-term LAM monotherapy.

	Subgroup A1 (n = 14)	Subgroup A2 (n = 11)	P
Age (yr)	41.9±12.9	43.9±5.0	0.75
ALT (IU/L)	183.6±87.7	263.9±115.8	0.09
HBV-DNA -log10 (copies/mL)	6.21±0.97	5.63±0.56	0.13
GRADE (0-18)	7.1±3.3	6.8±3.5	0.84
STAGE (0-6)	3.4±1.9	3.1±1.3	0.65
B2m (mg/dL) (baseline levels)	1775.5±304.1	1588.8±391.6	0.23
Duration of b2m elevation (mo)	3.8±3.4	7.3±2.6	0.02a
B2m elevation in 3 mo (%)	8/14 (57.1)	11/11 (100)	0.03a

ALT: alanine aminotransferase. B2m: b2-microglobilin.

^aP<0.05 vs other group.

Table 3 Cox proportional hazard model predicting VB by serum b2m levels. Results are presented with b2m being used as a continuous variable (number of months of b2m elevation) or as a dichotomous variable (decline vs elevation of serum b2m levels at 3 mo, as compared to baseline levels). The RR for b2m as a continuous variable reflects risk for VB for each less month of b2m elevation.

	Variable	RR	95%CI
b2m	Continuous	1.25	1.03–1.521
	Decline vs elevation	4.6	1.22–17.361

¹Indicates that the RR does not include 1. CI: confidence interval. RR: rate ratios.

Table 4 Cox proportional hazard model predicting VB by b2m at 3 mo as a dichotomous variable. The model simultaneously includes age, baseline values for ALT, grade of liver disease and initial serum HBV-DNA as covariates.

	Variable	RR	95%CI
Age (yr)	Continuous	0.98	0.92–1.05
ALT (IU/L)	Continuous	0.99	0.98–1.00
Grade (0–18)	Continuous	1.26	0.98–1.63
HBV-DNA (copies/mL)	High vs low	1.94	0.26–14.26
B2m (mg/dL)	Decline vs elevation	12.23	1.28–116.801

¹Indicates that the RR does not include 1. ALT: alanine aminotransferase. CI: confidence interval. RR: rate ratios.