Introduction
Suicide is a complex and important global public health problem (Turecki and Brent, 2016). Each year, nearly 800,000 suicide deaths occur worldwide, which makes it one of the leading causes of death (World Health Organization, 2018). Mental disorder is an important factor for suicide (Harris and Barraclough, 1997; Arsenault-Lapierre et al., 2004; Nock et al., 2010; Hoertel et al., 2015; Honings et al., 2016) and more than 90% of individuals who have committed suicide had had a diagnosis of mental illness at the time of death (Bertolote and Fleischmann, 2002), such as, for example, schizophrenia (Joiner et al., 2001; Hawton et al., 2005; Hor and Taylor, 2010). Schimanski et al. (2016) found that schizophrenia states can be non-specific indicators to suicide-related ideations and behaviors, and that schizotypy can still predict passive ideation even when the depression has been controlled.
Similarly, schizotypy is associated with an increased likelihood of suicide attempts. Schizotypy represents a phenotypic manifestation of putative vulnerability for schizophrenia-spectrum disorders, which means schizotypal individuals are at high risk of developing into full-blown psychosis (Nelson et al., 2013; Fonseca-Pedrero, 2017; Fonseca-Pedrero et al., 2017; Grant et al., 2018). The heterogeneity between schizotypy and schizophrenia lies in etiology, development and response of treatment (Kwapil et al., 2018; Lenzenweger, 2018). Conceptualized as a personality organization or trait, “schizotypy” can encompass similar neurocognitive, behavioral, and psychopathological problems as schizophrenia, and has the potential to develop into schizophrenia (Meehl, 1962; Kwapil et al., 2013). Therefore, schizotypy is prevailingly thought to be comprised of three basic factors, which are similar with the positive, negative, and disorganized dimensions of schizophrenia (Nelson et al., 2013). Positive symptoms are associated aberrant perceptual experiences, like magical ideation and referential thinking. Negative schizotypy is related to anergia, anhedonia, social disinterest, and flat affect (Kwapil et al., 2013, 2018). In a long-term follow-up cohort, 40% of the people with schizophrenia-spectrum disorders were found to have suicidal ideation, 23% had experienced suicidal attempts, and 6.4% had committed suicide (Fenton et al., 1997). The symptoms of schizotypal personality disorder even have been shown to predict the presence of lifetime suicide attempts after controlling for some risk factors, such as childhood abuse, and comorbid psychiatric diagnoses (Lentz et al., 2010). Moreover, Joiner et al. (2001) reported that people with schizotypal symptoms were more associated with self-hatred and suicidality, and that the combination of self-hatred and a diagnostic status of schizophrenia-spectrum symptoms may be a predictor of suicidality. The early intervention of suicidality targeting specific personality traits may be beneficial to decreasing suicide rates (Canal-Rivero et al., 2018).
There are many variables that can affect the relationship between schizotypy and suicidality, such as self-hatred (Joiner et al., 2001), depressive symptoms (Jahn et al., 2016), self-esteem (Jahn et al., 2016), and childhood abuse (Lentz et al., 2010). These negative experiences may be associated with the specific cognitive and interpersonal defects of individuals with schizotypy and they also tend to undermine these individuals' sense of value in respect of themselves and their lives. Frankl (1978) defined this emotional involvement of self-fulfillment and self-value as “meaning in life.” Meaningfulness is strongly related to depressive symptoms, but they have entirely different connotations: depressive symptoms focus on the assessment of negative emotions and external behavior performance whereas meaningfulness emphasizes the power of the inner self and the internal experience. In other words, the loss of meaningfulness comes about from many elements—not only depressive symptoms, but also traumatic events and inherent personality. Additionally, many studies have documented that life meaning has a beneficial effect on reducing suicidality (Edwards and Holden, 2001; Orbach et al., 2003; Kleiman and Beaver, 2013; Wilchek-Aviad, 2015). Focusing on the special personality disorder in schizotypy, therefore, meaningfulness can provide us more information on suicide precaution and intervention.
However, the current literature has yet to investigate whether life meaning is associated with suicidality in individuals with schizotypy. The purpose of the present study, therefore, is to explore whether the relationship between schizotypy and suicidality can be explained by meaningfulness. We hypothesize that meaningfulness can be a mediator of suicidality and schizotypy. Accordingly, we expect to find that meaningfulness will be inversely related to schizotypy and suicidality. In addition, we explore a model of the relationship among suicidality, meaningfulness, and schizotypy.
Discussion
The present study found a relationship among suicidality, meaningfulness, and schizotypy. Meaningfulness was found to be inversely associated with the other two factors and schizotypy was positively related with suicidality. What is more, the correlation between schizotypy and suicidality was substantially attenuated when meaningfulness was included, which may suggest that meaningfulness can partly mediate this relationship. Male and female participants showed different results regarding suicidality but gender did not have significant effects on the mediator effect of meaningfulness in schizotypy-suicidality relationship.
In line with previous studies, there was found to be a negative association between meaningfulness and suicidal behavior (Orbach et al., 2003; Bjerkeset et al., 2010; Wilchek-Aviad, 2015) and a positive correlation between schizotypy and suicidal behavior (Joiner et al., 2001; Kwapil et al., 2013; Teraishi et al., 2014; Jahn et al., 2016). Based on the assumption that individuals with high suicide risk question their life's value and have lost the desire to find their life's meaning, it is thought that people with less meaningfulness are at increased risk of having serious suicidal thoughts and attempts (Zhao et al., 2012). Additionally, people with schizotypy can have symptoms such as anhedonia (Meehl, 1962; Kwapil et al., 2013), which can make people unable to feel happiness and to hurt themselves or even commit suicide. There are gender differences in respect to suicidality, which has been proved by many studies. Although suicide brings more death to males, females register many more unsuccessful attempts (Sava and Papari, 2015), which is consistent with our finding. Compared with males, female suicide attempters are more likely to be influenced by social and interpersonal factors (Sun and Zhang, 2017), which is a key issue for people with schizotypal traits.
Nonetheless, the negative relationship between schizotypy and meaningfulness has to date received relatively little attention. Meaningfulness depends on culture and social connections, especially positive interactions with others (Baumeister et al., 2013; Lambert et al., 2013), while the social deficits of schizotypy (Triebwasser et al., 2012) and the “overall crisis of common sense” of these individuals (Stanghellini and Ballerini, 2006) greatly reduce their sense of meaning in life. The three-factor structure in the SPQ (Raine et al., 1994) indicates that people with schizotypal traits can have some psychotic-like symptoms, such as unusual perceptual experiences, paranoid ideation, and thoughts and behavior disturbances (Kwapil et al., 2018). Schizotypal adults maintain beliefs of conspiracy, irrational fear, or suspiciousness, which result in social anxiety, a lack of close friends, and other interpersonal problems. Moreover, these cognitive-perceptual, interpersonal, and disorganized features of schizotypy may result in a child having negative experiences early in the developmental process, such as verbal abuse and social exclusion (Raine et al., 2011; Wong and Raine, 2018). Consequently, peer victimization (Raine et al., 2011; Lam et al., 2016), and childhood trauma (Kelleher et al., 2008; Velikonja et al., 2015) caused by schizotypal features could give rise to a lack of meaningfulness. Additionally, individuals with an inability to experience pleasure, including a reduction in experiencing emotions overall or an increased sensitivity to negative emotions (Smith et al., 1995), could also experience a negative impact on their sense of enthusiasm, goals, and self-value. Therefore, with all the types of schizotypal personality, individuals' cognitive and behavioral dysfunctions can destroy their capability to understand life and achieve success. These individuals typically find less meaning and hope in life, have a lower quality of life, and may be at increased risk of experiencing mental health problems (Alminhana et al., 2017).
The present study found a direct effect of schizotypy on suicide behaviors, which is consistent with results from previous studies (Joiner et al., 2001; Kwapil et al., 2013), indicating that schizotypy may be a clinically useful indicator of suicide risk (Jahn et al., 2016). However, given the biological homology of schizotypy and schizophrenia (Triebwasser et al., 2012), it is not easy to alter these traits, which makes it difficult to effectively intervene in the suicide risk of schizotypal individuals. Our study found that meaningfulness mediates between schizotypy and suicidal behaviors, suggesting that, when it is difficult to directly change schizotypal personality traits, it may be possible to manage suicide risk by improving these individuals' sense of meaning in life. Interpersonal alienation, which affects such a sense of meaning, can be addressed through social skills training and group therapy (Mckay and Neziroglu, 1996). Methods that do not involve the pathological defects of schizotypy, such as promoting self-expression, integration, and reflection in the temporal dimension (Baumeister et al., 2013), also contribute to a sense of meaning. The specific cognitive style of schizotypy also suggests the potential value of initiatives such as creative activities and religious/spiritual well-being (Burch et al., 2006; Unterrainer et al., 2011). Further research is needed to determine whether these methods of enhancing sense of meaning are useful for schizotypal individuals.
Several methodological limitations of the present study should be acknowledged. First, as our research was of a cross-sectional design, a causal relationship cannot be established between meaningfulness and suicidality. Second, measurements used in our study were self-reported. Therefore, recall biases and reporting biases of some questions regarding suicidality might exist. Third, other confounding variables and background variables need to be considered or added into this model, such as a history of childhood abuse, depressive symptoms, and symptoms of anxiety. What is more, meaningfulness, as a potential mediator, requires an experimental study design and additional alternative approaches in order to obtain further confirmation. Despite these limitations, though, the current study proposes a possible mediator in the schizotypy–suicidality relationship, which suggests that assessing meaningfulness could provide more detailed information about suicide risk in individuals with schizotypy. Additionally, it may be an effective intervention as reducing suicide risk among people with schizotypy to improve their meaningfulness. Thus, our findings provide important insights into the development of life education and psychological crisis intervention in colleges and universities. However, there are several other risk factors that have not been tested yet, and no prior studies have comprehensively tested all well-established risk factors in a single model, in respect of which further studies are expected in the future.