Those with schizophrenia less likely to get COVID-19 booster

People with schizophrenia were less likely to have received a COVID-19 booster, while gaps in acquisition were greatest for the first vaccination, according to a retrospective cohort study published in JAMA Psychiatry.

“Individuals with schizophrenia are one of the most vulnerable groups at risk for a severe course of COVID-19 infection,” Dana Tzur Bitan, PhD, of the department of behavioral sciences at Ariel University in Israel, and colleagues wrote. “Recent studies have suggested that individuals with schizophrenia and psychotic disorders are either vaccinated to a lesser extent or tend to decline COVID-19 vaccinations to a greater extent, compared with the general population.”

The researchers sought to assess discontinuities between and among first, second and booster vaccinations among those diagnosed with schizophrenia.

The study utilized information from the databases of Israeli health care management organization Clalit Health Services to include 34,797 participants (mean age 50.8, 59.9% male) with schizophrenia and an equal number of matched controls (mean age 50.7, 59.9% male). Data were collected from the initial study period in November 2021, along with follow-up data from March 2020 to November 2021. Individuals with a diagnosis of schizophrenia at the onset of the pandemic and matched controls were included in the analysis, which measured rates of first, second and booster vaccinations as well as time needed to gain each.

Bitan and colleagues found that 6,845 participants (20.7%) with schizophrenia were completely unvaccinated, compared with 4,986 (14.5%) in the control group (OR, 0.65; 95% CI, 0.62-0.67). However, once initial vaccination occurred, there was no significant observable difference in acquisition of a second dose.

Data showed gaps emerged with the booster, as 18,469 individuals (74.7%) with schizophrenia acquiring the third vaccine compared with 21,563 (77.9%) of controls (OR, 0.83; 95% CI, 0.80-0.87). Researchers also uncovered, through Kaplan-Meier analyses, significant differences in time needed to become vaccinated, although time gaps were lower compared with those reported for initial vaccination (log-rank test,601.99 days; P<.001 for the first vaccination, compared with log-rank test,81.48 days, P<.001 for the booster).

“Countries worldwide should adopt strategies to mitigate the persistence of vaccination gaps in order to improve health care for this vulnerable population,” Bitan and colleagues wrote.