Interoceptive deficits (ID) have been associated with non-suicidal self-injury (NSSI) and suicidal behavior in multiple studies. Many of these studies are limited in scope, and have not fully examined possible mechanisms explaining how ID affect suicidal behavior.

This study assesses how self-reported ID relate to suicide ideation and attempts in six distinct and geographically diverse samples of adults (n = 2706) and one sample of adolescents (n = 436). Participants responded to a variety of self-report questionnaires and interviews.

Contrary to our hypothesis, self-reported ID were only associated with suicidal ideation in two samples, one of which was the adolescent sample. Largely consistent with our predictions, self-reported ID exhibited an indirect effect on suicide attempts through versatility of NSSI in four of the five adult samples tested. Finally, the indirect effects of self-reported ID on suicide attempts through NSSI versatility did not act indirectly through behaviorally assessed pain tolerance.

We found that, in adults, self-reported ID are not associated with suicidal ideation, but are connected with a history of suicide attempts, through an indirect effect via NSSI. Our findings also indicate that the mechanism of action leading from self-reported ID to suicidal behavior may differ between adolescents and adults, and relate to suicidal behavior independent of pain tolerance. Clinical implications and future directions are discussed.

Research is needed to identify the factors that explain the link between prior and future suicidality. This study evaluated possible mediators of the relationship between: (1) the severity of prior suicidality and (2) suicidal ideation severity at 3-month follow-up among a sample of high-risk military personnel.

US military service members referred to or seeking care for suicide risk (N = 624) completed self-report psychiatric domain measures and a clinician interview assessing prior suicidality severity at baseline. Three months later, participants completed a self-report measure of suicidal ideation severity. Three separate percentile bootstrap mediation models were used to examine psychiatric factors (i.e. alcohol abuse, anxiety sensitivity, hopelessness, insomnia, posttraumatic stress symptoms, suicidal ideation, and thwarted belongingness) as parallel mediators of the relationship between prior suicidality severity (specifically, suicidal ideation, suicide attempt, and overall suicidality – i.e. ideation/attempt severity combined) at baseline and suicidal ideation severity at follow-up.

Hopelessness, specifically, and the total effect of all mediators, each significantly accounted for the relationship between prior suicidality severity and subsequent ideation severity across models. In the models with attempt severity and overall suicidality severity as predictors, thwarted belongingness was also a significant mediator.

Hopelessness, thwarted belongingness, and overall severity of psychiatric indices may explain the relationship between prior suicidality severity and future suicidal ideation severity among service members at elevated suicide risk. Research is needed to replicate these findings and examine other possible mediators.

Fontan survivors have depressed cardiac index that worsens over time. Serum biomarker measurement is minimally invasive, rapid, widely available, and may be useful for serial monitoring. The purpose of this study was to identify biomarkers that correlate with lower cardiac index in Fontan patients.

This study was a multi-centre case series assessing the correlations between biomarkers and cardiac magnetic resonance-derived cardiac index in Fontan patients ⩾6 years of age with biochemical and haematopoietic biomarkers obtained ±12 months from cardiac magnetic resonance. Medical history and biomarker values were obtained by chart review. Spearman’s Rank correlation assessed associations between biomarker z-scores and cardiac index. Biomarkers with significant correlations had receiver operating characteristic curves and area under the curve estimated. In total, 97 cardiac magnetic resonances in 87 patients met inclusion criteria: median age at cardiac magnetic resonance was 15 (6–33) years. Significant correlations were found between cardiac index and total alkaline phosphatase (−0.26, p=0.04), estimated creatinine clearance (0.26, p=0.02), and mean corpuscular volume (−0.32, p<0.01). Area under the curve for the three individual biomarkers was 0.63–0.69. Area under the curve for the three-biomarker panel was 0.75. Comparison of cardiac index above and below the receiver operating characteristic curve-identified cut-off points revealed significant differences for each biomarker (p<0.01) and for the composite panel [median cardiac index for higher-risk group=2.17 L/minute/m2 versus lower-risk group=2.96 L/minute/m2, (p<0.01)].

Higher total alkaline phosphatase and mean corpuscular volume as well as lower estimated creatinine clearance identify Fontan patients with lower cardiac index. Using biomarkers to monitor haemodynamics and organ-specific effects warrants prospective investigation.