Association of Covid-19 vaccination uptake with recorded self-harm, neurodevelopmental disorders and mental health conditions during the Covid-19 pandemic: A nationwide e-cohort study in Wales, UK.

BACKGROUND

Understanding COVID-19 vaccine uptake among individuals who self-harm or with mental health conditions is critical to addressing health inequalities and guiding public health strategies/pandemic preparedness. Evidence on temporal trends and sociodemographic factors shaping vaccine uptake within these populations remains limited.

METHODS

We linked Wales Immunisation System data to demographic and healthcare records for 2.2 million individuals. Using modified Poisson regressions and growth models, we explored the association between self-harm, neurodevelopmental disorders, mental health conditions, and vaccine uptake from 8 December 2020-8 December 2023. Models were adjusted for age, sex, deprivation, ethnicity, and physical comorbidities.

FINDINGS: Attention Deficit Hyperactivity Disorder (ADHD), conduct disorder, drug use, and, to a lesser extent, self-harm were associated with lower incidence of vaccination. Conversely, those with autism spectrum disorder, or learning difficulty had slightly higher incidence of vaccination. Individuals with severe mental illness (SMI: schizophrenia, bipolar disorder and other psychotic disorders) exhibited a steeper initial increase and earlier peak in uptake, but their final coverage was lower. Belonging to an ethnic minority group and, to a lesser extent, being male, younger, or leaving in highly deprived areas were also associated with reduced uptake.

INTERPRETATION: Disparities in vaccine uptake exist among individuals with self-harm and mental health conditions, driven by intersecting health and social factors. Tailored interventions, effective communication, and trust-building strategies are critical to reducing these inequities. Underserved groups including those with SMI, ADHD, and self-harm, should be prioritised in future vaccination campaigns to improve equity.