The principles of prevention espoused by G. Rose¹ have underpinned many modern successes in health care. In areas such as cardiometabolic diseases, injuries and violence, and substance abuse, shifting the community distribution of risk factors has become the primary strategy. The ensuing reductions in disease burden have been striking.

Psychiatry remains an outlier. Over decades, the quality of clinical care has been improved, greater funding has been attracted, more and better trained mental health professionals have been grown, and the governance of mental health care has been upgraded². However, the emphasis in recent initiatives in high‐income countries has been overwhelmingly a further extension of treatment: early clinical intervention has been the dominant initiative taken up in government investments into the mental health of young people³.

Yet, this continuing expansion of government expenditure, prescribing of antidepressants and availability of psychological services has still not been accompanied by reductions in the prevalence of common mental disorders³. While it remains possible that this in part reflects a continuing failure to scale minimally‐sufficient treatments, the evidence from other fields of medicine suggests that a more likely explanation is the lack of scalable risk‐focused prevention strategies.

This failure to embrace population‐based approaches to prevention in psychiatry is understandable. Most clinicians find the endorsement of population perspectives difficult. For them, the individual is the unit of study¹. For psychiatry, the opacity of pathophysiological processes has supported the tendency to focus on interventions directed at the individual. Recent excitement about progress in genetics and neuroscience has reinforced this tendency, with both major research funding agencies and the pharmaceutical industry emphasizing the individual over the social context.

In this scenario, the paper by Fusar‐Poli et al in this issue of the journal⁴ raises questions around the optimal strategies for prevention in psychiatry. The overwhelming emphasis to date across common mental disorders, psychosis and bipolar disorder has been on individuals at high risk by virtue of early clinical symptoms or genetic predisposition. These selective and indicated approaches to prevention have targeted subjects at the tail of the distribution, with an aim of reducing the likelihood of transition to clinical caseness. However, this emphasis on individuals has been accompanied by a failure to address structural and social determinants.

E. Durkheim’s work, well over a century ago, drew the conclusion that suicide rates are stable and distinctive characteristics of populations. He viewed suicide as a collective phenomenon in which personal factors are less important than the social context. Similarly, strategies focused on the social, economic and regulatory context that bring a reduction in average alcohol consumption have been far more successful in reducing levels of alcohol use disorders than individually targeted interventions⁵. This principle that actions to reduce modest risks in a large group will generate greater benefits than targeting conspicuous risks in a small number should guide the prevention of mental disorders.

One challenge is that most risks for mental disorders lie outside the direct influence of the health sector. For young people, social determinants of mental health derive from inequitable gender norms, shifts in family structure and function, culture and religion, economic development and its consequences, digital technology, urbanization and planetary change. These social and structural determinants shape peer, family and community relationships, accessibility of service systems, the likelihood of experiencing major external events, as well as risks related to lifestyle and individual behaviour. For mental disorders, as for the physiological processes underpinning physical health, there are also sensitive periods in which risks are more likely to become embedded and when prevention will be more effective.

The COVID‐19 pandemic illustrates the influence of social and structural factors on the mental health of all age groups, but particularly the young. It also illustrates areas where psychiatry should be acting. The effects of lifestyle risk factors for mental disorders, including physical inactivity, screen time, irregular sleep and poor diets, have been enhanced. Even more profound have been the shifts in relationships, with disruption to friendships and peer interactions, heightened worries about and sometimes conflict with family members, confinement to home and loss of the social milieu of schools, including extracurricular activities.

In taking prevention in psychiatry forward, there are further lessons to be drawn from other areas of medicine¹. Epidemiology remains the underpinning discipline of public health, and, for psychiatry, epidemiology should adopt both life‐course and population perspectives. However, psychiatric epidemiology remains in a parlous state, particularly for children and young people. Global coverage for even basic estimates of prevalence lies under seven percent, with rates in low‐ and middle‐income countries substantially lower, and 124 countries having absolutely no data⁶. Coverage of risk factors is even weaker.

As noted by Fusar‐Poli et al, a life‐course perspective on mental health is essential⁴. Yet, a life‐course perspective would ideally extend across generations, given that familial clustering is the clearest of all risk factors. Beyond genetics, there are malleable intergenerational risk factors for mental disorders, ranging from the biological (e.g., epigenetic) through to the structural (e.g., inequitable gender norms), including those risks that become embedded prior to conception⁷. Longer‐term perspectives derived from prospective life‐course studies have the potential to guide prevention research and policy, particularly when combined with powerful new analytic tools for causal inference.

Recent intervention trials provide grounds for optimism. Schools will be one important context for prevention. Children and young people spend close to half their waking hours in school and education. Policy‐makers increasingly understand that poor student mental health affects learning and academic achievement. There are now examples from both high‐ and low‐resource settings that interventions promoting a positive school social climate and reducing bullying can substantially reduce symptoms of common mental disorder⁸. Other promising platforms include those based in local communities (e.g., girls clubs) and the new social environments created by digital media.

Interventions well beyond those traditionally regarded as the focus for prevention of mental disorders will also be important. Cash transfers have been widely adopted by governments in other areas of health and social policy, and seem to bring reductions in symptoms of mental disorder and promotion of well‐being in low‐resource settings where psychological interventions based on cognitive behaviour therapy have little or no effect⁹. Such findings suggest the value of inclusion of mental health into trials of non‐mental health interventions.

The dramatic deterioration in community mental health during the COVID‐19 pandemic heightens the imperative for psychiatry to shift beyond its comfort zone of the individual patient, and engage with the social, structural and political determinants of mental health.

G. Rose ¹拥护的预防原则为医疗保健领域的许多现代成功奠定了基础。在诸如心脏代谢疾病，伤害和暴力以及药物滥用等领域，改变风险因素在社区中的分布已成为主要策略。随之而来的疾病负担的减轻令人吃惊。

精神病学仍然是一个例外。几十年来，临床护理的质量得到了改善，吸引了更多的资金，培训了越来越多的精神保健专业人员，并且精神保健的管理水平得到了提升²。但是，在高收入国家中，近期举措的重点已经压倒性地进一步扩大了治疗范围：早期临床干预已成为政府对年轻人的心理健康进行投资的主要举措³。

然而，政府支出的持续增长，抗抑郁药的处方和心理服务的提供仍未伴随着常见精神障碍患病率的降低³。尽管这仍然有可能部分反映出持续扩展无法满足最低限度治疗需求的可能性，但其他医学领域的证据表明，更可能的解释是缺乏可扩展的以风险为中心的预防策略。

未能采用基于人群的精神病预防方法是可以理解的。大多数临床医生发现对人群观点的认可是困难的。对于他们来说，个人是学习的单位¹。对于精神病学而言，病理生理过程的不透明性支持了将注意力集中在针对个人的干预措施上的趋势。最近关于遗传学和神经科学进展的兴奋加剧了这种趋势，主要的研究资助机构和制药行业都在社会背景下强调个人。

在这种情况下，Fusar-Poli等人在本期杂志^4上发表的论文提出了有关预防精神病学的最佳策略的问题。迄今为止，由于早期的临床症状或遗传易感性，对常见的精神障碍，精神病和双相情感障碍的压倒性强调是高危人群。这些选择性的指示性预防方法已将对象定位在分布的尾部，目的是减少过渡到临床病例的可能性。但是，这种对个人的重视伴随着未能解决结构和社会决定因素的问题。

E. Durkheim的工作早在一个多世纪之前就得出了这样的结论，即自杀率是稳定的并且是人口的鲜明特征。他认为自杀是一种集体现象，在这种现象中，个人因素不如社会背景重要。同样，针对社会，经济和法规的战略，旨在减少平均饮酒量，在降低饮酒障碍水平方面，比单独针对性干预措施更为成功⁵。减少大批中度风险的行动所产生的益处要比针对一小部分中的明显风险产生的益处更大，这一原则应指导精神障碍的预防。

一项挑战是，精神疾病的大多数风险不在卫生部门的直接影响范围之内。对于年轻人而言，心理健康的社会决定因素来自不平等的性别规范，家庭结构和职能的转变，文化和宗教，经济发展及其后果，数字技术，城市化和地球变化。这些社会和结构决定因素决定着同伴，家庭和社区的关系，服务系统的可及性，发生重大外部事件的可能性以及与生活方式和个人行为有关的风险。对于精神障碍，作为支撑身体健康的生理过程，在敏感时期，风险也更容易被植入，并且预防将更加有效。

COVID-19大流行说明了社会和结构因素对所有年龄段，尤其是年轻人的心理健康的影响。它还说明了精神病学应该采取的行动领域。精神障碍的生活方式风险因素（包括缺乏运动，筛查时间，不规律的睡眠和不良饮食）的影响得到了增强。关系的变化更为深刻，包括对友谊和同伴互动的破坏，对家庭成员的担忧和有时加倍的冲突，仅限于住所以及学校社交环境的丧失，包括课外活动。

在推进精神病学的预防中，还应从其他医学领域汲取更多的教训¹。流行病学仍然是公共卫生的基础学科，对于精神病学而言，流行病学应同时考虑生命过程和人口观点。但是，精神病流行病学仍然处于孤零零的状态，特别是对于儿童和年轻人而言。即使是基本的患病率估计值，其全球覆盖率也低于7％，其中低收入和中等收入国家的患病率要低得多，而124个绝对没有数据的国家⁶。风险因素的覆盖范围甚至更弱。

正如Fusar-Poli等人指出的那样，从生命历程上看心理健康至关重要⁴。然而，鉴于家族聚类是所有风险因素中最清晰的一种，因此从理想的角度讲，人生历程可以跨越几代人。除遗传学外，还有许多可遗传的代际精神障碍风险因素，从生物学（例如表观遗传学）到结构性（例如不平等的性别规范），包括那些在受孕之前就已嵌入的风险⁷。从前瞻性生命历程研究得出的长期观点具有指导预防研究和政策的潜力，尤其是与强大的因果推理新分析工具结合使用时。

最近的干预试验提供了乐观的理由。学校将成为预防的重要环境。儿童和年轻人将近一半的醒来时间花在学校和教育上。政策制定者越来越多地意识到，学生心理健康状况不佳会影响学习和学习成绩。现在，无论是高资源还是低资源的环境，都有一些例子可以证明，促进积极的学校社会氛围和减少欺凌行为的干预措施可以大大减轻常见精神障碍的症状⁸。其他有前途的平台包括当地社区的平台（例如，女子俱乐部）和数字媒体创建的新社交环境。

远远超出传统上被认为是预防精神障碍的重点的干预措施也将是重要的。现金转移在卫生和社会政策的其他领域已被政府广泛采用，似乎可以减少精神障碍症状并促进低资源环境中的幸福感，在这种情况下，基于认知行为疗法的心理干预很少或根本没有效果⁹。这些发现表明将精神健康纳入非精神健康干预试验的价值。

在COVID-19大流行期间，社区心理健康状况急剧恶化，这使得精神病学必须超越个人患者的舒适范围，并参与心理健康的社会，结构和政治决定因素。