Depression is a common mental illness; according to the World Health Organization (World Health Organization, 2023), approximately 5 % of adults are affected by depression in any given year. Depression can be debilitating, leading to poor quality of life (Sadat et al., 2014), impaired social functioning (Kupferberg et al., 2016), reduced ability to engage in self-care (Iovino et al., 2020), and worsened physical health (Amato et al., 2001; Katon and Ciechanowski, 2002; WHO, 2021).

One of the most significant consequences of depression is suicidality; indeed, suicidality is one of the nine core symptoms of major depressive disorder (APA, 2022). Suicide is a public health crisis, with an estimated 700,000 suicide-related deaths occurring every year worldwide (WHO, 2021). The true prevalence of suicidality is likely even higher, as suicide rates are believed to be underreported due to differences in classification, cultural and religious stigma regarding suicide, and legal issues surrounding suicide in different countries (Hendin et al., 2008; Mascayano et al., 2015; Pritchard et al., 2020; Tandon and Nathani, 2018; WHO, 2021). Furthermore, even official suicide data are unreliable as suicides may be presented as death by accidents (Li and Yip, 2020).

Depression and suicidality are closely related – people with depression are more likely to experience suicidal ideation, suicide attempts, and death by suicide (Ribeiro et al., 2018). Indeed, regular screening for suicide is built into the gold-standard treatment guidelines for depression (Gelenberg et al., 2010). However, major depressive disorder is not the sole mental disorder that increases the risk of suicide; bipolar disorder, anxiety disorders, psychosis, substance use disorders, and certain personality disorders are also associated with an increased risk of suicide (Brådvik, 2018; Orsolini et al., 2020). Furthermore, there are factors other than diagnosable mental disorders that contribute to increased suicide risk, such as relationship problems, parental loss before the age of 11, a childhood history of physical or sexual abuse, family history of suicide, higher impulsivity, lower education, unemployment, and a history of a previous suicide attempts (Centers for Disease Control and Prevention, 2018; Ponsoni et al., 2018; Eikelenboom et al., 2019). Nonetheless, depression commonly emerges as the most significant predictor of suicide, both because it is one of the few disorders where suicidality is one of its symptoms as well as because specific symptoms of depression and depression consequences, including severe emotional distress, hopelessness, low self-worth, guilt, and social isolation, are themselves predictors of suicidality (Motillon-Toudic et al., 2022; Lépine and Briley, 2011).

The complex phenomenon of suicide is further complicated by cultural differences, which play an important role in one's experience of both depression and suicidality. Depression is experienced distinctly in different cultures (Goodmann et al., 2021; Kleinman, 2004), and attitudes toward mental illness and suicide as well as factors associated with suicidality likewise vary between cultural groups (Colucci, 2013). In many Western countries, depression is prevalent among individuals who die by suicide, though the same may not be true in other cultures, such as India (Ahmed et al., 2017; Arafat et al., 2022). Political and ethno-cultural factors can influence suicide rates; for instance, in former Soviet republics, suicide rates spiked and gradually reduced after the collapse of USSR (Rozanov, 2007). Religious prohibitions can reduce suicide rates, as is the case in Arabic countries, though such cultural and religious prohibitions also exacerbate suicide-related stigma (El Halabi et al., 2020; Eskin et al., 2020). Cultural traditions may also influence suicidality; for instance, in Latin American countries, familismo can be both a protective factor (when individual interests are aligned with the family) and a risk factor (when self-autonomy conflicts with family interests) for suicide ideation and attempts (Mascayano et al., 2015).

Although mental illness stigma is prevalent in many societies, specific personal or contextual factors may increase social acceptance of suicide in some cultures. For instance, within Japanese culture, suicide may be accepted as a means of preserving personal dignity or upholding justice (Rankin, 2012; Picone, 2012; Kawashima et al., 2020). In China, some groups tend to accept suicide as a response to severe life stressors, with women and younger and more educated individuals being more likely to report such acceptance (Li and Phillips, 2010). Suicide may also be less stigmatized when it is driven by patriotic/altruistic purposes (Lo, 2002) or the demonstration of self-determination (Goodman, 2005).

Given the cultural influences on both depression and suicidality as well as the perceived centrality of depression in suicide, the goal of this study is to better understand broad cultural differences in the relationship of depression and suicide.