Higher Levels of Inflammatory Markers in Patients With MDD and Suicide Risk

Patients with major depressive disorder (MDD) who are at risk for suicide have been shown to have higher levels of certain inflammatory markers, thus providing a possible starting point for early identification, along with the subsequent reduction in suicidal behaviors or use as novel treatment targets in risk management. Results were published in the Journal of Psychiatric Research.

The pathogenesis of suicide is complex in nature, involving psychological, sociological, biological, and clinical factors, all of which interact with each other. Recognizing that biomarkers reflective of pathophysiologic processes leading to the expression of suicidal behavior in patients with MDD would be helpful, Su and colleagues sought to explore the biomarker profile of suicide. Consequently, the current study evaluated a comprehensive range of serum markers that were sampled concurrently and previously have been linked to suicide.

Data from the study were derived from the Objective Diagnostic Markers and Personalized Intervention in MDD patients (ODMPIM) study, which was conducted in 9 centers of China from December 2013 through December 2016. The ODMPIM study recruited a total of 168 patients with MDD, including 50 participants at risk for suicide (mean age, 35.9 ± 11.3 years) and 118 participants without a risk for suicide (mean age, 39.0 ± 10.7 years). Among those patients at risk for suicide, 12 participants were recent suicide attempters over the past month and 9 participants had a history of suicide attempts. The 2 groups were similar with respect to age, gender, education level, smoking, drinking, body mass index, marriage, and employment status.

The results of the study demonstrated that a significantly higher percentage of patients with a risk for suicide had experienced adulthood adversity (62.0% vs 37.3%, respectively;

P =.003) but not childhood adversity (44.0% vs 44.1%, respectively; P =.094), compared with those participants with no suicide risk.

The severity of depression was significantly higher among patients with a suicide risk vs those without (22.8 ± 4.8 vs 20.1 ± 4.4, respectively; P =.001). Moreover, the proportion of melancholic type of MDD was also significantly in patients at risk for suicide than in those who were not at risk (88% vs 72%, respectively; P =.025). The 2 groups did not differ, however, in age of onset, antidepressant use, and family history of psychiatric disorders.

A total of 23 biomarkers were assayed. Compared with patients without suicide risk, patients with a suicide risk had significantly higher levels of chemokine (C-X-C motif) ligand 1

(CXCL-1; P <.001), interleukin (IL)-1β (P =.045), IL-2 Rα (P =.021), TLR-1 (P =.022), and AVP (P =.046), as well as lower levels of CCL-2 (P =.009) and FKBP52 (P =.012). After a more rigorous level of significance was used, however, only CXCL-1 remained significant.

Limitations of the study include the inability to identify a causal relationship between the increased inflammatory index and suicide risk in MDD patients, as well as that ODMPIM were not specifically designed to explore the suicide risk of MDD.

The investigators concluded that the findings from this study underscore the need for comprehensive treatment and prevention strategies in this population, in order to reduce the risk for suicide among patients with MDD.

Reference

Su Y-A, Lin J-Y, Liu Q, et al. Associations among serum markers of inflammation, life stress and suicide risk in patients with major depressive disorder. J Psychiatr Res. 2020;129:53-60. doi: 10.1016/j.jpsychires.2020.06.008