Microbiome in saliva linked to suicidal ideation in university students
A recent study published in the Scientific Reports suggests that microbial-genetic factors associated with suicidal ideation in university students.
Suicide is the second leading cause of death in individuals between the ages of 10–34 in the United States. Worldwide life-time prevalence of suicidal ideation (SI) was estimated to be 9.2% in a 2008 report of suicidal behaviors in 84,850 adults across 17 countries2. In a study of 67,000 degree-seeking college students across 108 institutions, 16,337 (24.3%) reported they harbored SI and 9.3% had made a suicide attempt3. The strongest association with suicidality, self-injury, suicide attempts, and mental health diagnosis in students was exposure to stress, in a dose-dependent manner. Three or more exposures to stress resulted in 4.25 to 10.06 times higher endorsement of SI3, consistent with the diathesis-stress model of depression
Here, salivary microbiota and major histocompatibility complex (MHC) human leukocyte antigen (HLA) alleles were compared between 47 (12.6%) young adults with recent suicidal ideation (SI) and 325 (87.4%) controls without recent SI. Several bacterial taxa were correlated with SI after controlling for sleep issues, diet, and genetics.
Four MHC class II alleles were protective for SI including DRB1*04, which was absent in every subject with SI while present in 21.7% of controls.
The results:
- Increased incidence of SI was observed with four other MHC class II alleles and two MHC class I alleles.
- Associations between these HLA alleles and salivary bacteria were also identified.
- Furthermore, rs10437629, previously associated with attempted suicide, was correlated here with SI and the absence of Alloprevotella rava, a producer of an organic acid known to promote brain energy homeostasis.
Hence, microbial-genetic associations may be important players in the diathesis-stress model for suicidal behaviors.
Reference:
Ahrens AP, Sanchez-Padilla DE, Drew JC, Oli MW, Roesch LFW, Triplett EW. Saliva microbiome, dietary, and genetic markers are associated with suicidal ideation in university students. Sci Rep. 2022 Aug 22;12(1):14306. doi: 10.1038/s41598-022-18020-2. PMID: 35995968; PMCID: PMC9395396.
Keywords:
Ahrens AP, Sanchez-Padilla DE, Drew JC, Oli MW, Roesch LFW, Triplett EW, Saliva microbiome, dietary, genetic, markers, associated, suicidal, ideation, university, students, Scientific Reports
