Mental health and neurodevelopmental factors relevant to recreational fitness-to-dive assessment: a structured review and clinical considerations

Introduction: Mental health and neurodevelopmental factors, including psychiatric disorders and psychotropic medication use, are commonly identified during recreational diving medical screening. However, guidance for fitness-to-dive assessment in this context remains limited and often relies on diagnostic categories and theoretical risk, contributing to variability in clinical decision-making. Methods: A structured review of the literature was conducted to identify evidence relevant to fitness-to-dive assessment where mental health and neurodevelopmental factors may be relevant. Searches of PubMed were supplemented by manual review of key references. Studies addressing cognitive function, behaviour, psychiatric stability, medication and substance effects and environmental influences in recreational diving were included and synthesised thematically. Results: Twenty-nine studies were included. The evidence base was heterogeneous and comprised primarily observational studies, experimental research on cognitive performance under diving conditions and a smaller number of reviews and guidance-oriented publications. Across the literature, functional capacity, behavioural responses under stress and psychiatric stability emerged as central determinants of diving safety. Cognitive performance is reduced under diving conditions, suggesting limited cognitive reserve and increased vulnerability to impairment. Panic and maladaptive behavioural responses represent key pathways to adverse outcomes. Medication use alone is not a consistent predictor of risk, although side effects and periods of clinical instability are relevant. Environmental factors inherent to diving may further amplify underlying vulnerabilities. Conclusions: Fitness-to-dive assessment in the context of mental health and neurodevelopmental factors cannot be determined by diagnosis alone. The available evidence supports a multidimensional, context-dependent approach incorporating functional capacity, behavioural reliability, psychiatric stability, medication effects and environmental demands. Assessment should be individualised and grounded in clinical judgement, recognising that risk is probabilistic rather than binary. These findings may support more consistent and clinically relevant decision-making in recreational diving.