Introduction: This study aimed to further analyze the associations between type 2 diabetes mellitus (T2DM) and hepatitis B virus (HBV) infection, and to investigate the relationships between T2DM and the mutations within the HBV major hydrophilic region (MHR).
Methodology: In this cross-sectional study, 3,377 persons (338 T2DM patients and 3,039 non-diabetics) were randomly selected. HBsAg detection was performed by enzyme-linked immunosorbent assay. The HBV MHR was amplified, sequenced, and analyzed by nested PCR.
Results: The seroprevalence of HBsAg was 21.30% in T2DM patients (72/338), which was significantly higher than in non-diabetics (15.53%). Compared to persons without T2DM, the proportion of T2DM patients positive for HBsAg was significantly elevated in males, people > 55 years (p = 0.039), and people with a body mass index (BMI) ≥ 24 kg/m2. Totally, 112 genotype B and 111 genotype C HBV sequences were isolated. No significant difference in HBV genotype distribution was observed between T2DM patients and non-diabetics. Compared to genotype C HBV-infected cases in non-diabetics, the amino acid substitution rates in the MHR were significantly higher in T2DM patients (p = 0.003). Moreover, seven HBV strains with stop codon mutations within the HBV S gene were identified: three from T2DM patients (5.45%) and four from non-diabetics (2.38%).
Conclusions: In China, T2DM is significantly associated with chronic HBV infections and genotype C HBV MHR mutations. Being males, > 55 years of age, and ≥ 24 kg/m2 of BMI are the risk factors of HBV infection in T2DM patients.