Amine metabolites, neuroendocrine findings, and personality dimensions as correlates of suicidal behavior

Levels of 5-hydroxyindoleactic acid (5-HIAA) and homovanillic acid (HVA) were measured in the cerebrospinal fluid (CSF) of 62 female inpatients with major depression (n = 19), schizophrenic disorder (n = 18), alcohol dependence (n = 13), and other disorders (n = 12). Nineteen patients had attempted suicide immediately before admission, and six had used violent methods. Fifty-three patients received a dexamethasone suppression test (DST) following lumbar puncture and all completed the Marke-Nyman Temperament Scale (Hungarian version) within 10 days. CSF 5-HIAA was significantly lower in patients who had made violent suicide attempts, but did not differ between suicide attempters who had taken drug overdoses and nonattempters. CSF HVA showed no significant differences. Dexamethasone nonsuppression occurred more frequently among attempters, but this difference did not reach statistical significance. Among the three personality dimensions of the Marke-Nyman Scale, validity was lower and stability higher in suicidal patients; both findings were more pronounced in the violent subgroup. CSF 5-HIAA and Marke-Nyman validity were inversely correlated to each other in all three subgroups, and violent attempters could be separated from the other two groups by their simultaneously low CSF 5-HIAA values and Marke-Nyman validity scores.     

CSF 5-HIAA levels are lower in impulsive as compared to nonimpulsive violent suicide attempters and control subjects.

BACKGROUND: We studied CSF 5-HIAA and HVA concentrations in violent suicide attempters and examined their relationship with depression, anxiety, and impulsivity. METHODS: CSF 5-HIAA and HVA concentrations were determined very shortly after hospital admission and compared to those of a matched control population. Clinical evaluation was performed concomitantly; the level impulsivity was evaluated by the Impulsivity Rating Scale (IRS). RESULTS: Twenty-three patients and 23 control subjects were included. According to the IRS, 14 patients were classified as impulsive, including all patients suffering from personality disorders, and 9 as nonimpulsive, with a main DSM-IIIR diagnosis of melancholia. CSF 5-HIAA concentrations in the suicide group were significantly lower than in control subjects. This difference was entirely due to the impulsive suicide attempters. There was an inverse correlation between the IRS score and CSF 5-HIAA (r = -.47, p = .02) and only a trend for HVA (r = -.41, p = .078) levels in the suicide group. CONCLUSIONS: This study of a group of violent suicide attempters distinguished a subgroup of patients diagnosed with personality disorder with high impulsivity scores and a subgroup of patients with the main diagnosis of severe depression. CSF 5-HIAA was significantly lower in impulsive violent attempters than in nonimpulsive violent attempters, therefore desintangling violence from impulsivity and linking this biologic abnormality to impulsivity.     

Cerebrospinal fluid monoamine metabolites and suicide

Prospective studies of the serotonergic system and suicide report that low 5-hydroxyindolacetic acid (5-HIAA) in the cerebrospinal fluid (CSF) and a history of attempted suicide predict suicide risk. Low CSF homovanillic acid (HVA) is reported to be associated with past and future lethality of suicide attempts but not with suicide. The interrelationships between monoamine metabolites, violent method, suicide intent and lethality of suicidal behaviour are complex. We hypothesized that CSF 5-HIAA and HVA levels are related to suicide intent, violence and lethality of suicidal behaviour. Fifteen male suicide attempters admitted to a psychiatric ward at the Karolinska University Hospital and eight healthy male volunteers were submitted to lumbar puncture and CSF 5-HIAA and HVA were assayed. Suicide intent with the Beck Suicide Intent Scale (SIS), lethality and violence of suicidal behaviour were assessed. All patients were followed up for causes of death. Six suicides and one fatal accident were identified with death certificates. Mean CSF 5-HIAA but not CSF HVA differed between suicides and survivors. Violent suicides had higher suicide intent and CSF 5-HIAA than non-violent suicides. In violent suicides, CSF 5-HIAA levels were negatively correlated with SIS. Greater suicide intent may be associated with greater aggressive intent and predicts a violent suicide method.     

Aggressivity, suicide attempts, and depression: relationship to cerebrospinal fluid monoamine metabolite levels.

BACKGROUND: We have proposed a stress-diathesis model for suicidal behavior, in which major depression is a stressor and the diathesis is shared with aggression. Neurotransmitter correlates of the stress or diathesis have not been adequately evaluated by previous studies, because they did not simultaneously examine the relationship of multiple neurotransmitters to all three psychopathologies in the same population. In the present study we investigated the relationship of monoamine metabolites to aggressivity, suicidal behavior, and depression in patients with mood disorders. METHODS: Ninety-three drug-free subjects with a major depressive episode underwent lumbar puncture and psychiatric evaluation. Cerebrospinal fluid CSF levels of 5hydroxyindolacetic acid (5-HIAA), homovanillic acid (HVA) and methoxy-hydroxy-phenylglycol (MHPG) were assayed. The relationships between monoamine metabolites and clinical variables were statistically evaluated. RESULTS: Higher lifetime aggressivity correlated significantly with lower CSF 5-HIAA. Lower CSF 5-HIAA and greater suicidal intent were found in high-lethality suicide attempters compared with low-lethality suicide attempters. Low-lethality attempters did not differ biologically from nonattempters. No correlation between CSF HVA and any of the psychopathological variables was found. Only aggression showed a trend statistically in correlating positively with CSF MHPG levels. CONCLUSIONS: Lower CSF 5-HIAA concentration was independently associated with severity of lifetime aggressivity and a history of a higher lethality suicide attempt and may be part of the diathesis for these behaviors. The dopamine and norepinephrine systems do not appear to be as significantly involved in suicidal acts, aggression, or depression. The biological correlates of suicide intent warrant further study.     

Monoamine metabolites in CSF and suicidal behavior

Cerebrospinal fluid concentrations of the monoamine metabolites 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenyl glycol (MHPG) were measured in 30 psychiatric patients who had attempted suicide and 45 healthy volunteers. The suicide attempters had a significantly lower CSF 5-HIAA level than the controls, especially those who had made more violent attempts. After adjustment for differences in body height and age between controls and patients, the difference in 5-HIAA level became even more marked. Concentrations of 5-HIAA also were lower than normal in suicidal patients who were not diagnosed as depressed at the time of lumbar puncture, while HVA levels were lowered only in the depressives. A follow-up study of these and 89 more patients (depressed and/or suicidal) revealed a 20% mortality by suicide within a year after lumbar puncture in patients with a CSF-HIAA level below the median.     

Low CSF oxytocin reflects high intent in suicide attempters

Data from animal studies suggest that oxytocin is an important modulating neuropeptide in regulation of social interaction. One human study has reported a negative correlation between CSF oxytocin levels, life history of aggression and suicidal behaviour. We hypothesized that CSF oxytocin levels would be related to suicidal behaviour, suicide intent, lifetime interpersonal violence and suicide risk. 28 medication free suicide attempters and 19 healthy volunteers participated in this cross sectional and longitudinal study. CSF and plasma morning basal levels of oxytocin were assessed with specific radio-immunoassays. The Beck Suicide Intent Scale (SIS), the Freeman scale and the Karolinska Interpersonal Violence Scale (KIVS) were used to assess suicide intent and lifetime violent behaviour. All patients were followed up for cause of death. The mean follow-up was 21 years. Suicide attempters had lower CSF oxytocin levels compared to healthy volunteers p=0.077. In suicide attempters CSF oxytocin showed a significant negative correlation with the planning subscale of SIS. CSF oxytocin showed a significant negative correlation with suicide intent, the planning subscale of SIS and Freeman interruption probability in male suicide attempters. Correlations between plasma oxytocin levels and the planning subscale of SIS and Freeman interruption probability were significant in male suicide attempters. Lifetime violent behaviour showed a trend to negative correlation with CSF oxytocin. In the regression analysis suicide intent remained a significant predictor of CSF oxytocin corrected for age and gender whereas lifetime violent behaviour showed a trend to be a predictor of CSF oxytocin. Oxytocin levels did not differ significantly in suicide victims compared to survivors. CSF oxytocin may be an important modulator of suicide intent and interpersonal violence in suicide attempters.     

The Marke-Nyman Temperament (MNT) scale in relationship with monoamine metabolism and corticosteroid measures in suicide attempters

Abstract

Various monoaminergic measures as well as corticosteroid deviances have repeatedly been linked to depression or suicidal behavior. With the purpose to study these biological markers in relationship with temperament, the Marke-Nyman Temperament (MNT) questionnaire was administered in a sample of 89 suicide attempters. The subjects were diagnosed according to the DSM-III-R and subgrouped according to suicide method into “violent” and “nonviolent” attempters, and into “repeaters” (with previous attempt) and “nonrepeaters” (without previous attempts). The subjects were also subgrouped according to MNT patterns into 5 MNT clusters. Lumbar punctures were performed and the monoamine metabolites homovanillic acid (HVA). 5-hydroxyindoleacetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylglycole (MHFG) in the cerebrospinal fluid (CSF) were analysed. The levels of plasma cortisol and 24. urinary cortisol were determined and dexamethasone suppnssion tests (DST) were performed. The activity of the enzyme monoamine oxidase (MAO) in platelets was determined.

Among the alcoholic patients, the biological markers showed several specific correlations with temperament. In this group. low Solidity (reflecting impulsiveness) was significantly associated with low levels of CSF HVA. CSF 5-HIAA. urinary cortisol and low platelet MAO activity. The Stability (reflecting emotional distance towards others) was significantly and positively associated with urinary cortisol and platelet MAO activity. This seems to reflect the two previously described subgroups of alcoholism, with early and late onset, respectively.

In the whole sample, we found a positive correlation between urinary cortisol and Stability. The biological markers showed no clear differences between the MNT clusters. We could not replicate earlier findings of an association between impulsiveness (low solidity) and low levels of 5-HIAA or low MAO activity in platelets in the whole sample of suicide attempters.     

抑郁症患者自杀与脑脊液单胺代谢产物的关系

目的：探讨抑郁症患者自杀与脑脊液单胺代谢产物之间的关系。方法：应用高效液相色谱法，测定24例抑郁症患者(自杀组10例，无自杀组14例)及25例对照组5-羟色胺(5-HT)代谢产物5-羟吲哚乙酸(5-HIAA)，去甲肾上腺素(NE)代谢产物3-甲基-4-羟苯乙二醇(MHPG)及多巴胺(DA)代谢产物高香草酸(HVA)的浓度。结果：抑郁症自杀组5-HIAA浓度显著低于对照组，男性自杀组5-HIAA浓度、HVA浓度和HVA／MHPG比值均显著低于男性对照组，女性则无显著差异：结论：抑郁症患者自杀可能与5-HT和DA功能低下以及DA和NE之间的关系改变有关。     

Natural killer cell activity and csf monoamine metabolites in suicide attempters

Abstract

The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD 16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function.     

The relationship between CSF HVA/5-HIAA ratio and suicide intent in suicide attempters.

There is a need to find stable biomarkers for suicidal behavior and suicide prediction. Reduced homovanillic acid/5-hydroxyindolacetic acid (HVA/5-HIAA) ratios in cerebrospinal fluid (CSF) in depressed suicide attempters have been reported. Suicide intent is a predictor of repetition of attempts and suicide. In the present study we investigated the relationship of HVA/5-HIAA ratio to the scales rating suicide intent and depressive symptoms. Fifteen consecutive medication-free male suicide attempters admitted to a psychiatric ward at the Karolinska Hospital and eight healthy male volunteers underwent lumbar puncture and had the CSF monoamine metabolite levels assayed. Patients were assessed with the Beck Suicide Intent Scale (SIS), the Montgomery Asberg Depression rating Scale (MADRS) and the Chapman Scale of Anhedonia. Within the suicide attempter group, HVA/5-HIAA ratio was significantly associated with the Suicide Intent Scale (SIS), but not with the MADRS scale or the Chapman Scale of Anhedonia indicating that the HVA/5-HIAA ratio may be a biomarker of suicide intent.     

Natural killer cell activity and CSF monoamine metabolites in suicide attempters

The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function.     

A proposed model of the development of suicidal ideations

BackgroundSuicidal ideations may precede suicide attempts. They are of particular concern in psychiatric populations because psychopathology is a major risk factor for suicide. The factors affecting the development of suicide ideations may differ among psychiatric patients with and without a previous suicide attempt and individuals without a psychiatric diagnosis.ObjectivesThe aim of this study is to develop a model of suicide ideation in psychiatric patients and the general population.MethodThe study included 196 participants: 92 psychiatric patients with a previous suicide attempt (“attempters”); 47 psychiatric patients who had never attempted suicide (“non-attempters”); and 57 healthy control subjects. Data were collected on socio-demographic parameters, clinical history, and details of the suicide attempts. Participants completed a battery of psychological instruments assessing aggression–impulsivity, mental pain (including depression and hopelessness) and communication difficulties, in addition to negative life events. Findings were correlated with suicidal ideation by group.ResultsThe correlations of the different variables with suicidal ideation differed between suicide attempters and non-attempters; therefore, the model was analyzed separately for each group. The study yielded three major findings: negative life events had a significant effect on both anger-in and impulsivity in non-attempters but not in attempters; hopelessness moderately contributed to suicidal ideations in attempters but not in non-attempters; loneliness contributed significantly to depression in non-attempters but was less distressing in attempters.ConclusionThe mechanism underlying suicidal ideation appears to differ between psychiatric patients who have previously attempted suicide and those who have not, supporting a dual model of suicidal ideation. Although this is only a preliminary study, these findings are important for furthering our understanding of the process of transition of suicidal thoughts to completion of suicide. These results need further replication with a larger cohort of subjects.     

Biochemistry and suicidal behavior in depressed patients

The present study was undertaken in order to further explore the relationship between monoamine levels and hypothalamic-pituitary-adrenocortical (HYPAC) functioning and suicidal behavior in depressed patients. One hundred and thirty-two depressed inpatients participated in the NIMH Collaborative Study on the Psychobiology of Depression. Similar to previous reports, our suicide attempters were younger, more likely to be bipolar, had an earlier age at onset, and displayed more psychotic features. No correlation between cortisol hypersecretion or Dexamethasone Suppression Test (DST) nonsuppression and suicide attempts were found. Only the pre-DST evening plasma cortisol distinguished the groups, being lower in the attempter group. We were unable to confirm the previously reported correlation between cerebrospinal fluid (CSF) 5-hydroxyindoleacetic acid (5-HIAA) and suicide attempts. Of the monoamines examined, only urinary and plasma 3-methoxy-4-hydroxphenylglycol (MHPG) differed between suicide attempters and nonattempters, showing lower levels in the attempter group. There was a trend for CSF MHPG in the same direction. This latter reduction was restricted to the bipolar group.     

CSF 5-HIAA, suicide intent and hopelessness in the prediction of early suicide in male high-risk suicide attempters

OBJECTIVE: To study the predictive value of the Beck Suicide Intent Scale (SIS), the Beck Hopelessness Scale (BHS) and of 5-hydroxyindoleacetic acid (5-HIAA) in the cerebrospinal fluid for future early suicide in a group of high-risk male suicide attempters. METHOD: Fifteen consecutive male suicide attempters admitted to a psychiatric ward at the Karolinska Hospital, who were not receiving any treatment with antidepressants were diagnosed according to DSM-III, assessed with SIS and BHS and submitted to lumbar puncture. All patients were followed up for cause of death. RESULTS: Five early suicides (within 2 years) were identified. Mean cerebrospinal fluid (CSF) 5-HIAA differed between suicides and survivors. Low CSF 5-HIAA was identified in those who committed early suicide. Neither the Suicide Intent Score nor the Hopelessness Score distinguished suicides from survivors. CONCLUSION: In high suicide risk hospitalized male psychiatric patients CSF 5-HIAA may be a better predictor of early suicide after attempted suicide than SIS or BHS.     

Characteristics of Chinese suicide attempters admitted to a geropsychiatric unit.

PURPOSE: To investigate the characteristics for elderly Chinese suicide attempters in Taiwan and make comparisons with Western reports. METHODS: During a six-year period, patients admitted to a geropsychiatric unit as a result of a suicide attempt were investigated for factors related to the suicide attempt. RESULTS: Of the 722 admissions during this period, 55 (7.6%) were patients who had been admitted due to suicide attempt. The sex and age distributions for the suicide attempters were similar to those for other patients. The most common diagnoses were depressive disorders (56.4%), followed by delusional disorders (20.0%). A total of 121 suicide motives were cited for the 55 attempters, an average of 2.2 per person, with depressive symptoms commonly found on admission. During the first week of hospitalization, 53 attempters (96.4%) still exhibited suicidal ideation and six patients made a further suicide attempt, however, only three patients retained suicidal ideation on discharge. CONCLUSIONS: Our study confirms previous Western reports that depressive disorders are commonly manifested in elderly suicide attempters. There were differences in the motives and methods employed for the suicides, possibly due to cultural difference and/or sample source. Most of the suicide attempters exhibited a favourable response with hospitalization.     

CSF biomarkers in suicide attempters--a principal component analysis

Lindqvist D, Janelidze S, Erhardt S, Träskman‐Bendz L, Engström G, Brundin L. CSF biomarkers in suicide attempters – a principal component analysis. Objective: The objective of the present study was to identify biological patterns (factors) among 20 cerebrospinal fluid (CSF) biomarkers in suicide attempters and subsequently analyse their association with suicidal behaviour. Method: We measured kynurenic acid, orexin, homovanillic acid (HVA), 5‐hydroxyindoleacetic acid (5‐HIAA), 3‐methoxy‐4‐hydroxyphenylglycol, chemokines, matrix metalloproteases and cytokines in the CSF of 124 drug‐free suicide attempters. Patients were evaluated for suicidality and psychiatric symptoms using well‐defined psychiatric rating scales and followed‐up regarding future suicide. We used principal component analysis to identify factors among the biological substances. Results: Four factors were extracted from the 20 biomarkers, explaining 52.4% of the total variance. Factors 1 and 2 were characterized by high loadings of chemokines and cytokines respectively. They were both associated with severe depressive symptoms. Factor 2 was also associated with a high suicidal intent. Factor 4 was characterized by strong loadings of the monoamine metabolites 5‐HIAA and HVA, as well as orexin and interleukin‐6. High scores on this factor were found in patients who performed a violent suicide attempt and in patients who subsequently completed suicide. Conclusion: Our results suggest that specific combinations of CSF biomarkers may discriminate between types of suicidal behaviour and indicate increased risk for future suicide.     

Electrodermal reactivity in male and female depressive patients who later died by suicide

On the basis of earlier studies on electrodermal responsiveness in patients with suicide attempts, an investigation on electrodermal activity (EDA) in former depressive inpatients was carried out. Male and female depressive inpatients who died of suicide later and participated in an habituation experiment during their inpatient treatment were identified retrospectively and compared (strictly matched by age and sex) to depressive suicide attempters with violent or nonviolent methods, suicide ideators and a nonsuicidal depressive group. In the first part of the study only male depressives (n= 12) who had committed suicide after or during inpatient treatment were compared with their controls. The hypothesis of a expected low electrodermal responsiveness and a fast habituation as an peripheral expression of a central impulse or violence control disturbance could not be confirmed. This was done in the second part of this study. We came to the following results: 1) a tendency to a faster habituation in the violent suicides compared with nonsuicidal depressives and violent suicide attempters plus violent suicide group in male depressives compared to suicide attempters (SA), nonviolent suicide ideators and nonsuicidal depressives. 2) A significant difference with faster habituation rates in a male and female violent suicide group compared with nonsuicidal depressives and again comparing a group of male and female violent suicides and SA with nonviolent SA, suicide ideator and nonsuicidal depressive controls. These results may reflect a dysregulation of violence and impulsivity control mechanism as an underlying disorder or personality trait.     

Functional imaging, serotonin and the suicidal brain

The involvement of the serotonergic system in the pathophysiology of suicidal behaviour has been established through indirect and direct research on serotonin and its metabolites and on serotonin transporters and receptors. Indirect research results include a reduced 5-HIAA in cerebrospinal fluid in violent suicide attempters and a blunted increase in prolactin after a fenfluramine challenge. Direct post-mortem research demonstrated an increase in 5-HT2A receptors. Direct in vivo functional imaging with PET or SPECT demonstrated a reduction in 5-HT2A binding index in suicide attempts in anxious and depressed suicide attempters and an increase in 5-HT2A binding in impulsive suicide attempters. These results are in keeping with 5-HT2A binding studies in depressed patients and impulsive animal research. Interestingly, both an increase and a decrease in 5-HT2A binding index seem to normalize with SSRI treatment.     

Cerebrospinal fluid magnesium and calcium related to amine metabolites, diagnosis, and suicide attempts

Magnesium and calcium concentrations were measured in the cerebrospinal fluid (CSF) of 15 neurological controls and 41 psychiatric patients suffering from major depression (n = 16), schizophrenic disorder (n = 15), or adjustment disorder (n = 10). All subjects were women 19-67 years of age and free from drugs at the time of the study. CSF was evaluated for 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and cortisol (CS) levels, and all patients received a dexamethasone suppression test (DST) following lumbar puncture. CSF calcium levels did not differ among groups, although we found a trend toward higher mean levels in both depression and schizophrenia. By contrast, CSF magnesium was found to be significantly lower in both depression and adjustment disorder; if, however, patients who had made suicide attempts were excluded, the difference became insignificant. Patients who had made suicide attempts (by using either violent or nonviolent means) had significantly lower mean CSF magnesium level irrespective of the diagnosis. CSF calcium did not correlate with magnesium, 5-HIAA, HVA, CS, global severity, therapeutic response, or DST, but CSF magnesium correlated significantly with CSF 5-HIAA, especially after correcting for age and body height. Both variables seemed to be primarily related to recorded suicide attempts, but decreased magnesium was not limited to violent cases.     

CSF 5-HIAA and DST non-suppression — Orthogonal biologic risk factors for suicide in male mood disorder inpatients

Two biomarkers of suicide risk; non-suppression in the dexamethasone suppression test (DST) and low 5-hydroxyindoleacetic acid (5-HIAA) in the cerebrospinal fluid (CSF) have been reported to be predictors of suicide in mood disorders. The interrelation of the two systems seems to be different in suicide attempters compared with depressed inpatients who have not made a suicide attempt, indicating that the two biomarkers may be seen as independent. This investigation examined the interrelation of low CSF 5-HIAA and DST non-suppression in suicide victims with mood disorder. Fifty-eight mood disorder inpatients not receiving any treatment with antidepressants underwent lumbar puncture and the DST. Plasma cortisol levels at 8:00 a.m., 4:00 p.m. and 11:00 p.m. were analysed in relation to CSF 5-HIAA. All patients were followed up for causes of death and suicides were verified with death certificates. During follow-up (mean 21 years), 11 (19%) patients had committed suicide. In male suicide victims (n = 6), the serum cortisol level at 4:00 p.m. showed a significant positive correlation with CSF 5-HIAA. Low CSF 5-HIAA predicted all early suicides (within 1 year), whereas all males who committed suicide after 1 year were DST non-suppressors. In female suicide victims (n = 5), the post-DST serum cortisol did not correlate with CSF 5-HIAA. Low CSF 5-HIAA and DST non-suppression are orthogonal biologic risk factors for suicide in male mood disorder inpatients. CSF 5-HIAA is associated with short-term suicide risk; dysregulation of the hypothalamic-pituitary-adrenal axis seems to be a long-term suicide predictor.