Clinical correlates and prognostic implications of severe suicidal ideation in major depressive disorder

Abstract

Suicidal ideation (SI) is a risk factor for suicidal behaviour. To ascertain the clinical correlates and prognostic impact of severe SI, we analysed 249 outpatients with major depressive disorder (MDD) and suicidal thoughts included in the COmbining Medications to Enhance Depression outcome (CO-MED) trial. Patients with severe SI (36%) were younger at disease onset (P = 0.0033), more severely depressed (P = 0.0029), had more lifetime suicidal behaviour (P < 0.0001) and psychiatric comorbidities (panic disorder: P = 0.0025; post-traumatic stress disorder: P = 0.0216), and a history of childhood maltreatment (neglect: P = 0.0054; emotional abuse: P = 0.0230; physical abuse: P = 0.0076; sexual abuse: P = 0.0016) than those experiencing low-moderate SI. After controlling for depression score, severe SI was positively correlated with lifetime suicidal behaviour (OR [95% CI]: 1.26 [1.12–1.41]), panic disorder (1.05 [1.00–1.12]), and childhood maltreatment (neglect: 1.93 [1.13–3.30]; physical abuse: 2.00 [1.11–3.69]; sexual abuse: 2.13 [1.17–3.88]), and inversely correlated with age of onset (0.97 [0.95–0.99]) and sleep-onset insomnia (0.76 [0.61–0.96]). Finally, the occurrence of serious lifetime suicidal behaviour was predicted by SI severity (2.18 [1.11-4.27]), bipolar score (1.36 [1.02–1.81]), and childhood sexual abuse (2.35 [1.09–5.05]). These results emphasise the importance of assessing childhood maltreatment and bipolar liability in MDD to estimate suicidal behaviour risk.

Neurological, Metabolic, and Psychopathological Correlates of Lifetime Suicidal Behaviour in Major Depressive Disorder without Current Suicide Ideation

“…However, the impact of underlying bipolarity on suicide risk in MDD has been extensively discussed by Rihmer and Rihmer [27]. In our previous work, childhood maltreatment and subthreshold bipolarity were associated with the intensity of SI [48]. The current analysis added a new piece to the mosaic: these variables may increase suicide risk independently of suicide ideation and may be markers of suicidality in subjects who did not report ideation.…”

“…Cholesterol has been studied as a biomarker of suicidality for more than three decades since early reports suggested a possible association between excess mortality from violence and the use of cholesterol-lowering drugs [105]. In most studies, low total cholesterol has been associated with an increased risk of SB, including SI [44], suicide attempt [41‒43] and suicide completion [42‒108]. In a review of the literature on cholesterol lipoproteins, a meta-analysis found a negative association between LDL levels and suicide attempts in patients with MDD [109].…”

Anhedonia and Depressive Disorders

“…However the majority of studies suggest that anhedonia should be considered a relevant risk factor for possible suicidal behaviors, this is an issue considering the persistence of suicidal ideation also after treatment [ 47 - 49 ]. Higher levels of anhedonia in depression have been linked to higher suicidal ideation both in cross-sectional and longitudinal studies.…”

Molecular Changes Associated with Suicide

“…Several risk factors have been proposed for the association of MDD and suicidality. These risk factors include male gender, depression severity, age of onset and course of depression, a family history of psychiatric disorders, previously attempted suicide, comorbid psychiatric disorders such as anxiety disorders, and abuse and violence during childhood [37][38][39][40]. In addition, specific symptoms of depression, such as hopelessness, self-blame, irritability, insomnia and bipolar features, have also been associated with an increased risk of suicidality in individuals with MDD [39,40].…”