Some priorities in targeting social determinants to achieve prevention of mental disorders
Authors: Brian O'Donoghue
Journal: World Psychiatry (2024)

Kirkbride et al1 provide convincing evidence of a causal relationship between social determinants and poorer mental health outcomes. The extent, complexity and prevalence of these determinants could lead to hopelessness at the prospect of addressing the inequalities and inequities involved. However, the authors instil hope and optimism by providing examples of interventions delivered at the family, school, neighbourhood or societal level that have been effective in primary prevention. They then offer seven key recommendations for action by mental health professionals, policy makers and researchers to prevent or reduce mental health problems that arise from social determinants. All these recommendations warrant further discussion. However, I will focus on two: the need to prioritize interventions providing positive outcomes across multiple domains, and the demand to utilize the causal architecture approach in psychiatric epidemiology. Kirkbride et al propose that mental health outcomes should be evaluated in any policy, programme or intervention targeting social determinants. This would be a highly informative and beneficial endeavour. However, while achievable, it would require a significant shift in how research is conducted, and would involve establishing and maintaining relationships and collaborations across multiple disciplines, faculties and departments. The benefits would be reciprocal, as the functional outcomes of education, employment, housing and diversion from the criminal justice system are likely to be very meaningful from the viewpoint of several stakeholders. This action would also entail that mental health clinicians and researchers have a role in advocacy at a government level, as any policy that affects the key social determinants will have a knock-on effect on mental health at a population level. However, clinicians are already overburdened with the high prevalence of mental disorders, and academics need to be continuously productive in a highly competitive environment for grants and fellowships. The benefits of this approach would take years to realize and can be challenging to evaluate directly. Therefore, those time-consuming endeavours of across-discipline collaborations and advocacy would need to be acknowledged by the authorities and institutions that award grants and promotions, as some are already doing. Kirkbride et al call for the causal architecture approach to be used in psychiatric epidemiology, as this would lead to an understanding of the pathways between one or more exposures and the disease/disorder. This approach could result in the identification of modifiable risk factors and inform where interventions should be targeted. The mechanisms by which social determinants contribute to the aetiology of mental disorders are likely to be complex and could also differ amongst individuals. For example, in the case of childhood adversity and trauma, the experience itself of being the victim of abuse or adversity could lead to subsequent mental health problems, but, additionally, the manner by which individuals are supported (or not supported) by their family and loved ones, as well as by the legal or medical system, could also be involved in the pathway2. Another example of a likely complex relationship is that between low income and poor mental health, since socioeconomic differentials as well as psychological perceptions and self-esteem, in addition to an absolute lack of material resources, may lead to a higher risk of experiencing a mental disorder3. Another key aspect of the causal architecture approach is that the sampling should be from a representative population. As the authors rightly point out, there is a relative lack of research in lower- and middle-income countries, despite these countries representing over 80% of the world's population4. There have been recent endeavours to undertake methodologically robust epidemiological studies in the Global South. In one such study, the incidence of untreated psychotic disorders was found to be three times higher in Northern Trinidad compared to both the Kancheepuram district in India and Ibadan in Nigeria5. The incidence rate observed in Northern Trinidad (59.1 per 100,000) would have ranked as the third highest if considered in a previous meta-analysis including 44 estimates of the international incidence of psychotic disorders6. Both substance use and levels of community violence and crime have increased markedly in Trinidad in recent years. This suggests that there are settings in which the potential for primary prevention of psychotic disorders by targeting social determinants could be particularly high. It is also worth considering the proportion of mental disorders that interventions targeting social determinants could prevent. Population attributable fractions have been estimated to be nearly 38% for childhood adversity and just under 10% for cannabis use in schizophrenia, and to be 13.4% for childhood sexual abuse in depression7. This is in keeping with the call by Kirkbride et al for social determinants to be fully integrated into the bio-psycho-social model of mental health and illness. It also highlights that primary prevention strategies aimed at social determinants could reduce the incidence of mental disorders but not eradicate them. Considering this, while Kirkbride et al focus on primary prevention, social determinants could also inform improvements and advancements in secondary prevention. To ensure an equitable allocation of resources, a secondary prevention strategy could be the determination of resourcing and funding of services on the basis of the geographic prevalence of social determinants, such as social deprivation, fragmentation and rates of migrants and minority ethnic groups. Indeed, it has been demonstrated that the incidence of psychotic disorders can be reliably predicted based on the prevalence of social determinants in geographically defined areas resulting from census data8. Yet, the majority of mental health services continue to be funded on a per capita basis. There are also inequalities and inequities for certain groups in accessing treatments; for example, individuals from racial and minority ethnic groups are less likely to be referred to or receive psychological interventions in the UK9. This unequal distribution of resources and these barriers to accessing services need to be addressed alongside the efforts for primary prevention. The call to action by Kirkbride et al is ambitious, but its goals are achievable. It can help to address the underlying inequalities and inequities within our societies that contribute to the development of mental health problems and may sustain them across further generations.