Résilience - COVID-19 - Résilience - Coronavirus disease 2019

Attitudes towards vaccines and competence to consent to vaccination against COVID-19 in individuals with schizophrenia – SCHIZOVAC

Attitudes toward vaccines and competence to consent to COVID 19 vaccination in schizophrenia

Recent evidence suggests that individuals with schizophrenia are at high risk for severe COVID-19 and should be prioritized for vaccination. Several important barriers could negatively affect the uptake of a COVID-19 vaccine in this population, among them attitudes of individuals with schizophrenia towards vaccination and impaired decision-making capacities. However, competence to consent to vaccination and general attitudes towards vaccines remains unexplored in schizophrenia.


The main aims of our project is to assess :<br />1. Attitudes towards vaccines and intention to vaccinate against COVID-19 in individual with<br />schizophrenia compared to nonclinical participants<br />2. Competence to consent to COVID 19 vaccines in patients compared to nonclinical participants<br />3. Clinical, cognitive and psychological determinants of attitudes toward COVID 19 vaccines in<br />individuals with schizophrenia<br />4. Clinical, cognitive

Written informed consent was obtained for all participants, and the study was approved by the CHU Montpellier’s institutional review board (IRB ID : 202100768).
We conducted a cross-sectional study in the University Department of Adult Psychiatry of Montpellier, France between April 2021 to October 2021. Adults with a diagnosis of schizophrenia (International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes F20,, were included.
Participants consecutively admitted to the different sites were initially identified by regular examination of electronic medical records and consultations with ward nursing staff. Patients were in a second step approached for a research interview. Those assenting were given full details of the study. Judgments on mental capacity to participate to this study were based on a clinical assessment (review of notes and clinical interview). All participants provided informed and written consent. Missing data were collected and participants were then administered the measures, for a duration of approximately one hour.

Vaccination status and health-related indicators. COVID-19 vaccination status was recorded for all participants as either no vaccination or first dose of vaccine/fully vaccinated.
Competence to consent to COVID-19 vaccination was assessed with the MacArthur Competence Assessment Tool for Treatment, (MacCAT-T).
Attitudes toward vaccines. Negative general attitudes towards vaccines were measured using the 12-item Vaccination Attitudes Examination Scale (VAX; Martin & Petrie, 2017).
Intent to take a COVID-19 vaccine. For the unvaccinated participants we also measured the intent to take a COVID-19 vaccine. We used a single item question taken from the IPSOS-WEF COVID-19 VACCINE GLOBAL SURVEY JANUARY 2021 - GLOBAL PR: “If a vaccine for COVID-19 is available for me, I would get it”.
Trust in institutions. In order to evaluate the trust in institutions, we used the same methodology than Murphy et al. (2021). Participants were asked to indicate the level of trust they had in political parties, the parliament, the government, the police, the legal system, scientists, doctors and other health professionals
Psychotic symptoms were assessed with the Positive and Negative Syndrome Scale and cognition with the Global cognitive functioning: Montreal Cognitive Assessment. Analysis began September 2021 and ended October 2021.

One-hundred participants with a diagnosis of schizophrenia were recruited between April 2021 to October 2021. Seventy-two controls were recruited from the general population in Montpellier

In this cross-sectional study 56.3% of the sample were classified as having diminished capacities to make treatment decision for COVID-19 vaccination. Poor performance was associated with poorer cognition and higher level of psychotic symptoms. Importantly, the subgroup of patients with diminished decisional capacity had a lower vaccination rate than the group with preserved capacity, suggesting that diminished competence to consent might constitute a barrier for COVID-19 vaccination.

We also found that :
People with schizophrenia had similar general attitudes towards vaccines than individuals from the general population
People with schizophrenia were under-vaccinated (64% versus 77.8%) despite similar general attitudes towards vaccination and higher willingness to be vaccinated in non vaccinated against COVID-19 compared to the controls (41.7% versus 21.5%).
In both groups, non-vaccinated individuals had more negative attitudes towards vaccines.
General positive attitudes towards vaccines were negatively associated with persecutory ideation and negative symptoms in patients.

There is an urgent need to develop cognitive and behavioral interventions to improve informed consent to vaccination in this population.
Similarly, there is an urgent need to develop targeted vaccination programs for this population (De Hert et al., 2021; Mazereel et al., 2021).

It is now well recognized that the life expectancy of patients with severe mental disorders is reduced by 10 years compared to the general population and up to 15 years for schizophrenia, due to frequent somatic co-morbidities and poor general health. Several recent studies have shown that while individuals with a diagnosis of schizophrenia are note systematically over-represented regarding hospitalization rates for COVID 19, they are however at higher risk of COVID-related mortality than the non-clinical population. As such, people with schizophrenia should therefore be prioritised in vaccine allocation strategies. However, several important barriers could negatively affect the uptake of a COVID-19 vaccine in this population, among them attitudes of individuals with schizophrenia towards vaccination and impaired decision-making capacities. Indeed, impaired decision-making ability has been repeatedly observed in schizophrenia patients. Using both experimental tasks, such as the Iowa Gambling Task and clinical tools such as the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) or for Treatment (MacCAT-T). Ability to make treatment decision has been proposed as one of the most impaired decision-making capacity in schizophrenia. In addition, a recent large-scale study showed that reduced trust in institutions, and both conspiracy beliefs and persecutory ideas, two psychological features highly present in individuals with schizophrenia, were positively associated with COVID 19 vaccine hesitancy and resistance. Nevertheless, to our knowledge no studies of the attitudes of people with schizophrenia regarding vaccines against SARS-CoV-2 exists and particularly concerning the French population.

SCHIZOVAC adresses this question by 1) assess attitudes of people with schizophrenia regarding vaccination against SARS-CoV-2 2) Exploring if individuals with schizophrenia have the competence to consent to treatment to COVID-10 vaccines and 3) what are the key factors that negatively influence decicion-making capacity and attitudes towards vaccination in this clinical population.

Project coordination


The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.


CHU de Montpellier Centre Hospitalier Universitaire de Montpellier

Help of the ANR 79,841 euros
Beginning and duration of the scientific project: April 2021 - 9 Months

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