It has been demonstrated in several studies that often alexithymic individuals may show significantly higher levels of psychological distress than non-alexithymics and may develop “functional” somatic symptoms and psychiatric symptoms such as anxiety and depression (1–3).

Moreover, it has been suggested that alexithymic subjects may scarcely respond to both pharmacotherapy and psychotherapy. The characteristic attributes of alexithymic behavior are predominantly manifest in social interactions with high emotional significance (4). The affect-avoiding interpersonal pattern behavior showed by such subjects is often maladaptive and may elicit disorders and conflicts in important relationships, lastly contributing the risk of development of psychiatric symptoms such as depression or anxiety, thus increasing the risk of suicide (5). Moreover, it has been demonstrated that alexithymia should be considered as a relative stable personality trait (6, 7), enhancing vulnerability to depressive symptoms (8, 9), and is generally associated with higher risk of death for several causes (accidents, injury, or violence) (10).

There is an increasing evidence that alexithymia may be considered a risk factor for suicide, even simply increasing the risk of development of depressive symptoms or per se (11). This evidence comes out from the results of several studies conducted on both general population and clinical samples of patients with psychiatric disorders or medical conditions.

Therefore, the aim of this narrative review was to elucidate the possible relationships between alexithymia and suicide risk, evaluating published studies on general population, suicide attempters, and subjects with psychiatric disorders [such as anxiety disorders, affective disorders, eating disorders (EDs), etc.]. Studies were identified searching the electronic databases such as MEDLINE, Embase, PsycINFO, and the Cochrane Library.

So far, two main and relevant studies on general population (both conducted in Finland) have been done to evaluate the relationships between alexithymia and suicide risk.

First, a sample of 1,722 participants (735 men and 987 women) were evaluated (12). In particular, the study focused on the hopelessness, a widely recognized risk factor for suicide (13). Researchers found that a lower financial status, poor personal health, and reduced working ability independently associated with hopelessness. Interestingly, the probability of moderate or severe hopelessness was considerably increased in individuals with alexithymia and suicidal ideation. They concluded that life discontent, depressive symptoms, alexithymia, and suicidal ideation were the most powerful factors associated with moderate to severe hopelessness, but causal association was not possible to argue as this was a cross-sectional study.

The second study analyzed a huge sample of 1,563 subjects in the Kuopio Depression Study (14). Interestingly, this study proved that the most common self-report measure of alexithymia [the 20-item Toronto Alexithymia Scale (TAS-20)] showed a large overlap with a largely used self-report inventory for measuring the severity of depression, the Beck Depression Inventory. The associations of alexithymia with levels of suicidal ideation across time “…were no longer independent when adjusted for concomitant changes in the level of depressive symptoms…” (14), as reported by author themselves. Thus, the conclusion was that depressive symptoms were the mediators between alexithymia and psychiatric morbidity, hence including suicide ideation.

All considered, studies on general population support the hypothesis of a relationship between alexithymia and suicidal ideation mediated by depressive symptoms.

Several studies on clinical samples of patients with psychiatric disorders have confirmed the hypothesis that alexithymia may increase the suicide risk, especially through the development of depressive symptoms.

We have discussed some limitations of the reviewed studies above in the text. However, some other general limitations should be acknowledged.

The principal limitation of most studies on the relationships between alexithymia and suicide is that these are often cross-sectional and not prospective. Therefore, it may be difficult to interpret the identified associations and draw predictive conclusions.

Moreover, almost all reviewed studies employed the TAS-20, a self-report scale, to measure alexithymia. Even if the TAS-20 is a very useful tool in everyday “real-world” clinical practice to screen whether the subject is positive for alexithymia, it should be noted that findings based on self-report tools may be source of bias that in some cases may be poorly informative. Task-based studies should be preferred, but, to date, no task studies evaluating alexithymia were developed. However, future studies should employ the Toronto Structured Interview for Alexithymia (TSIA) (53), a reliable and valid structured interview for assessing the alexithymia construct, that can overcome the limitations of TAS-20 (54, 55).

Finally, the lack of control for adequate and comparable measures of depression and alexithymia or adequate statistical models of the interaction between depression and alexithymia (mixed models rather than ANCOVA) was a limitation of several reviewed studies, and this should be recognized.

Taken together, the almost all studies have pointed out a significant relationship between alexithymia and an increased suicide risk.

These findings may be explained in several ways. One is in accordance to the theory proposed by Freyberger of acute “secondary alexithymia” as a response to stressful conditions (56). The “acute secondary alexithymia” (56) can be defined as a transient, state-dependent experience that may occur as a consequence of subjective distress and can decline when an acute episode of illness has resolved (57). As the presence of alexithymia may worsen an existing psychiatric or medical disease, this worsening may be related to the development of suicidal ideation per se or through the development of depressive symptoms or even a comorbid clinically relevant MDE (4). However, even if alexithymia may be a state-dependent phenomenon (i.e., alexithymia may worsen during an acute disease episode, as described above), it should be considered a relatively stable personality trait that may be also present even before the onset of a psychiatric disorder or a medical disease (6, 7). Thus, research findings may be also in accordance with the “stress-alexithymia hypothesis” (58): alexithymia may be a chronic condition [maybe with an onset during infancy or early adolescence and often in consequence of childhood abuse or neglect (49, 59)] characterized by a pronounced inflammatory state with an impaired hypothalamic–pituitary–adrenal axis reactivity to even mild to moderate life stressors (60). Therefore, it should be deemed as a chronic state reaction as a response to stressful conditions that may always complicate a psychiatric disorder or a medical disease (61).

In conclusion, the importance of alexithymia screening in everyday clinical practice and the evaluation of clinical correlates of alexithymic traits should be integral parts of all disease management programs and, especially, of suicide prevention plans and interventions. The TAS-20 is a very useful tool in everyday “real world” clinical practice to screen subject positive or not for alexithymia, even if it is a self-report scale with all limitations of such instruments. However, if a subject is positive for alexithymia on TAS-20, a careful evaluation should be conducted (also completing the assessment of alexithymia with the TSIA, if possible) concerning the presence of depressive symptoms and suicidal ideation.

We state that (1) all authors have read the paper and approved the data and the conclusions presented therein; (2) each author believes that the paper represents honest work; and (3) all authors have contributed to the present paper with equal effort.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.