Association between leptin levels and severity of suicidal behaviour in schizophrenia spectrum disorders

• Published in: Acta psychiatrica Scandinavica 2019-05, Vol.139 (5), p.464-471
• Main Authors: Gohar, S. M., Dieset, I., Steen, N. E., Mørch, R. H., Vedal, T. S. J., Reponen, E. J., Steen, V. M., Andreassen, O. A., Melle, I.
• Format: Article
• Language: English
• Subjects: Adult; Age of Onset; C-Reactive Protein - analysis; Cross-Sectional Studies; depression; Depressive Disorder - complications; Depressive Disorder - psychology; Female; Humans; Leptin; Leptin - metabolism; lipid; Male; Mental disorders; Original; Psychotropic Drugs - adverse effects; Risk Factors; Schizophrenia; Schizophrenia - blood; Schizophrenia - complications; Schizophrenia - diagnosis; Schizophrenic Psychology; Self destructive behavior; Severity of Illness Index; Smoking; Smoking - epidemiology; Smoking - psychology; Suicidal Ideation; Suicide; Suicide - psychology; Suicide - trends; Suicides & suicide attempts
• ISSN: 0001-690X; 1600-0447
• DOI: 10.1111/acps.13019

Objective Associations between suicidality and lipid dysregulation are documented in mental illness, but the potential role of leptin remains unclear. We examined the association between leptin and suicidal behaviour in schizophrenia, together with the influence of other clinical and biological indices. Method We recruited a sample of 270 participants with schizophrenia spectrum diagnoses. Blood samples were analysed for leptin, while symptom severity was assessed by Positive and Negative Syndrome Scale (PANSS) and Inventory of Depressive Symptomatology (IDS‐C). Patients' history of suicidal behaviour was categorized into three subgroups based on IDS‐C suicide subscale: No suicidal behaviour, mild/moderate suicidal behaviour and severe suicidal behaviour with/without attempts. Results Mild/moderate suicidal behaviour was present in 17.4% and severe suicidal behaviour in 34.8%. Both groups were significantly associated with female gender (OR = 6.0, P = 0.004; OR = 5.9, P = 0.001), lower leptin levels (OR = 0.4, P = 0.008; OR = 0.5, P = 0.008) and more severe depression (OR = 1.2, P < 0.001; OR = 1.1, P < 0.001) respectively. Smoking (OR = 2.6, P = 0.004), younger age of onset (OR = 0.9, P = 0.003) and less use of leptin‐increasing medications (OR = 0.5, P = 0.031) were associated with severe/attempts group, while higher C‐reactive protein CRP (OR = 1.3, P = 0.008) was associated with mild/moderate group. Conclusion Lower leptin levels were associated with higher severity of suicidal behaviour in schizophrenia.