ABSTRACT
The ChAdOx1 nCoV-19 vaccine (AZD1222) was used in Thailand during the early outbreak of coronavirus disease 2019 (COVID-19). A previous study showed a low immune response in diabetes patients after the first dose of the AZD1222 vaccine. Furthermore, humoral immune responses after the second vaccination were inconsistent. This study evaluated the immunogenicity following the first and second doses of the AZD1222 vaccine in people with type 2 diabetes (T2D) compared with the general population of Thailand. This was a prospective, single-center cohort study. 59 adults with T2D and 118 age- and sex-matched healthcare personnel were eligible. The participants received two doses of AZD1222 12 weeks apart. Antibodies against the receptor-binding domain (anti-RBD) of the SARS-CoV-2 spike protein, using an automated electrochemiluminesence immunoassay (ECLIA), were measured at baseline, 8 and 12 weeks after the first dose of vaccine, and 4 weeks after the second dose of vaccine. The anti-RBD levels were reported as the geometric mean concentration (GMC) and compared between groups using the geometric mean ratio (GMR). A total of 177 participants were included: The average age of 59 T2D patients was 60.1 years (SD: 11.4), and 31 (52.5%) of them were female. The GMC of anti-RBD 8 and 12 weeks after the first vaccination were significantly lower in T2D (week 8 60; 17.05 BAU/mL, 95% confidence interval [CI] 11.1-26.19, P = 0.035, week 12; 24.68 BAU/mL, 95% CI 16.4-37.0, P = 0.002) than in those without diabetes (week 8; 29.79 BAU/mL, 95% CI 22.07-40.42, week 12; 50.67 BAU/mL, 95% CI 40.62-63.20). However, there was no difference in the GMC of anti-RBD 4 weeks after the second vaccination among groups (T2D; 687.95 BAU/mL, 95% CI 462.7-1022.7, Normal; 697.95 BAU/mL, 95% CI 583.7-834.5, P = 0.947). In both groups, the GMC of anti-RBD was persistently high without decline 12 weeks after the first vaccination. Albuminuria was a major factor related to low humoral immune responses in T2D patients after the second dose of AZD122 vaccine (the GMR was 0.29, 95% CI 0.08-0.98, P = 0.047) whereas the HbA1C level and age were not. Immunogenicity in T2D cases was lower than in the normal population after the first dose of the AZD1222 vaccine. The two doses of AZD122 vaccine induced immunity in T2D equal to that of normal individuals in Thailand. People with diabetes should be boosted as soon as possible to induce adequate immunity to prevent COVID-19 infection.
Subject(s)
COVID-19 , ChAdOx1 nCoV-19 , Diabetes Mellitus, Type 2 , Immunogenicity, Vaccine , Female , Humans , Male , Middle Aged , ChAdOx1 nCoV-19/administration & dosage , ChAdOx1 nCoV-19/immunology , ChAdOx1 nCoV-19/therapeutic use , Cohort Studies , COVID-19/complications , COVID-19/immunology , COVID-19/prevention & control , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/immunology , Prospective Studies , SARS-CoV-2 , Southeast Asian People , Thailand/epidemiology , Immunogenicity, Vaccine/immunology , AgedABSTRACT
BACKGROUND: Vaccines for SARS-CoV-2 have been critical for preventing disease. Previous research showed patients with diabetes have impaired immunity. This study aimed to determine the immunity to coronavirus after CoronaVac by comparing patients with type 2 diabetes (T2D) and healthcare workers (HCW). MATERIALS AND METHODS: A prospective cohort study evaluated immune responses and safety after two doses of CoronaVac in T2D and HCW groups at Chulabhorn Hospital. The levels of total antibodies against the receptor-binding domain (anti-RBD) of the SARS-CoV-2 spike protein at baseline and 4 weeks after vaccination were collected. The level of anti-RBD concentrations was reported as geometric mean concentration (GMC) and compared between groups using the geometric mean ratio (GMR). RESULTS: 81 participants were included; 27 had T2D and 54 were HCW. After complete vaccination, anti-RBD concentrations were not significantly different between T2D (57.68 binding antibody units (BAU)/mL, 95% confidence interval (CI) = 29.08; 114.44) and HCW (72.49 BAU/mL, 95% CI = 55.77; 94.22) groups. Subgroup analysis showed the GMC of anti-RBD was significantly lower in T2D patients with dyslipidaemia (50.04 BAU/mL) than in T2D patients without dyslipidaemia (341.64 BAU/mL). CONCLUSIONS: The immune response at 4 weeks after two doses of CoronaVac did not significantly differ between patients with T2D and HCW.
