Hypertension and/or a history of hypertension is associated with lower antibody titres and breakthrough infection following COVID-19 vaccination with inactivated viral vaccines, according to a recent article published in Vaccine.
Researchers in Indonesia conducted 2 studies of health care workers who received 2 doses of the CoronaVac COVID-19 inactivated virus vaccine. A prospective cohort study of 101 health care workers assessed the association between clinical and demographic variables, antibody response, and vaccine effectiveness at Dr. Soetomo General Hospital in Surabaya, Indonesia. The investigators also conducted a separate retrospective study of 2714 health care workers at Dr. Soetomo General Academic Hospital as well as Syarifah Ambami Rato Ebu Hospital in Bangkalan, Indonesia, to determine the incidence of breakthrough infections at 14 days or more after the second vaccine dose.
In the prospective antibody response study, researchers analyzed blood samples of 101 health care workers (all nonpregnant and aged 20 years or older) at 1, 3, and 5 months after receiving their second vaccination dose. The investigators also conducted medical exams and interviews to gather demographic and medical history data regarding age, sex, BMI, smoking habits, and presence or history of comorbidities. Serological testing was conducted from the blood samples and the level of IgG against the SARS-CoV-2 receptor-binding domain as well as the white blood cell profile was detected, analyzed, and/or determined. The investigators then used this data to identify statistically significant associations between demographic factors/co-morbidities and antibody levels.
The researchers’ primary finding was a significant association between blood pressure and antibody response (P=.038). Specifically, researchers found that participants with hypertension (≥140 mmHg systolic blood pressure and/or ≥90 mmHg diastolic blood pressure) had a reduced antibody response, with the most significant effect noted at 5 months post-vaccination with inactivated COVID-19 vaccine. Furthermore, data also suggested that a history of hypertension, regardless of whether it was well-controlled or not, was associated with a lower antibody response following vaccination with inactivated SARS-CoV-2.
With respect to other comorbidities: diabetes was associated with a lower IgG level in participants, but the difference at each time point was not statistically significant; history of cardiovascular diseases (CVD) was associated with a significant reduction of IgG at 3 months post-second vaccination dose. With respect to demographic factors: no association was found between antibody response and demographic factors such as sex or BMI; lower antibody titres were observed in participants who smoked.
In the second study of breakthrough infections, the association between breakthrough COVID-19 infections 14 days post second vaccination dose and various demographic and clinical factors was retrospectively analyzed in a cohort of 2714 health care workers (68.5% less than 40 years old; 53.5% male). The analysis found participants with hypertension showed a significantly higher risk of contracting breakthrough infection than individuals with normal blood pressure (odds ratio: 1.382 (95% CI: 1.041–1.834); P =.031). The researchers’ data recorded 498 (20.5%) breakthrough infections in participants with normal blood pressure (n=2432) during the study period vs 74 (26.2%) cases of breakthrough infections among those with hypertension (n=282) during the same period. No significant association was found between breakthrough infection and other comorbidities (including diabetes, CVD, asthma/lung disease, and allergic disease). Additionally, no significant associations were found between any demographic factors and the incidence of breakthrough infection.
Study limitations included self-reporting of body weight, height, and medical history, as well as lack of assessment of neutralizing antibodies, cellular immunity, and vaccine protection against different virus variants.
Both studies consistently revealed that both hypertension and a history of hypertension significantly affected antibody response and COVID-19 breakthrough infections among participants who received 2 vaccine doses of vaccination with inactivated virus, said study authors. “Thus, blood pressure control might be important to improve the efficacy of inactivated virus vaccine,” they added.
Soegiarto G, Wulandari L, Purnomosari D, et al. Hypertension is associated with antibody response and breakthrough infection in health care workers following vaccination with inactivated SARS-CoV-2. Vaccine. Published online May 27, 2022. doi:10.1016/j.vaccine.2022.05.059