常见身体疾病（如心血管疾病、癌症和神经退行性疾病）的人群患有较高比例的重度抑郁障碍（MDD），相较于普通人群。另一方面，患有MDD的人群出现了较多种身体疾病的风险增加。这种高水平的共病性与更糟糕的结果、较低的治疗坚持性、更高的死亡率、更大的医疗保健利用率和成本有关。共病性还会导致一系列临床挑战，例如更复杂的治疗联盟、与适应性健康行为相关的问题、药物-药物相互作用以及与用于身体和心理障碍的药物引起的不良事件。解释上述共病性高发率的潜在原因包括共享的遗传和生物途径。后者包括炎症、肠道微生物组、线粒体功能和能量代谢、下丘脑-垂体-肾上腺轴失调以及大脑结构和功能。此外，MDD和身体疾病共同具有一些与社会因素（如社会经济地位）、生活方式变量（如体力活动、饮食、睡眠）和应激生活事件（如童年创伤）相关的先兆因素。药物治疗和心理治疗是共病MDD的有效治疗方法，并且引入生活方式干预以及合作护理模式和数字技术提供了改善管理的有希望的策略。本文旨在详细介绍MDD和特定身体疾病的共病性流行病学情况，包括患病率和双向风险；共享的潜在生物途径可能与MDD和常见身体疾病的发病机制相关；以及作为共同风险因素和保护因素的社会环境因素。我们总结了与共病MDD和身体疾病的人群的最佳护理相关的未来方向和新兴研究。© 2023 World Psychiatric Association.

Populations with common physical diseases - such as cardiovascular diseases, cancer and neurodegenerative disorders - experience substantially higher rates of major depressive disorder (MDD) than the general population. On the other hand, people living with MDD have a greater risk for many physical diseases. This high level of comorbidity is associated with worse outcomes, reduced adherence to treatment, increased mortality, and greater health care utilization and costs. Comorbidity can also result in a range of clinical challenges, such as a more complicated therapeutic alliance, issues pertaining to adaptive health behaviors, drug-drug interactions and adverse events induced by medications used for physical and mental disorders. Potential explanations for the high prevalence of the above comorbidity involve shared genetic and biological pathways. These latter include inflammation, the gut microbiome, mitochondrial function and energy metabolism, hypothalamic-pituitary-adrenal axis dysregulation, and brain structure and function. Furthermore, MDD and physical diseases have in common several antecedents related to social factors (e.g., socioeconomic status), lifestyle variables (e.g., physical activity, diet, sleep), and stressful live events (e.g., childhood trauma). Pharmacotherapies and psychotherapies are effective treatments for comorbid MDD, and the introduction of lifestyle interventions as well as collaborative care models and digital technologies provide promising strategies for improving management. This paper aims to provide a detailed overview of the epidemiology of the comorbidity of MDD and specific physical diseases, including prevalence and bidirectional risk; of shared biological pathways potentially implicated in the pathogenesis of MDD and common physical diseases; of socio-environmental factors that serve as both shared risk and protective factors; and of management of MDD and physical diseases, including prevention and treatment. We conclude with future directions and emerging research related to optimal care of people with comorbid MDD and physical diseases.© 2023 World Psychiatric Association.