Suicide completion in secondary mental healthcare: a comparison study between schizophrenia spectrum disorders and all other diagnoses

BACKGROUND Suicide completion is a tragic outcome in secondary mental healthcare. However, the extent to which demographic and clinical characteristics, suicide method and service use-related factors vary across psychiatric diagnoses remains poorly understood, particularly regarding differences between 'schizophrenia spectrum disorders (SSD)' and 'all other diagnoses', which may have implications for suicide prevention in high risk groups. METHODS 308 patients who died by suicide over 2007-2011 were identified from the South London and Maudsley NHS Foundation Trust Biomedical Research Centre Case Register. Demographic, clinical, services use-related factors, 'full risk assessment' ratings and the Health of the Nation Outcome Scale (HONOS) scores were compared across psychiatric diagnoses. Specifically, differences between patients with and without SSD were investigated. RESULTS Patients with SSD ended their lives at a younger age, were more frequently of Black ethnicity and had higher levels of social deprivation than other diagnoses. Also, these patients were more likely to have HONOS and 'risk assessment' completed. However, patients who had no SSD scored significantly higher on 'self-injury' and 'depression' HONOS items and they were more likely to have the following 'risk assessment' items: 'suicidal ideation', 'hopelessness', 'feeling no control of life', 'impulsivity' and 'significant loss'. Of note, 'disengagement' was more common in patients with SSD, although they had been seen by the staff closer to the time of suicide than in all-other diagnoses. Whilst 'hanging' was the most common suicide method amongst patients with non-SSD, most service users with a SSD diagnosis used 'jumping' (from heights or in front of a vehicle). CONCLUSIONS Suicide completion characteristics varied between SSD and other diagnoses in patients receiving secondary mental healthcare. In particular, although clinicians tend to more frequently recognize suicide risk as a focus of concern in patients who have SSD, who are therefore more likely to have a detailed risk assessment documented; 'known' suicide risk factors appear to be more relevant in patients with non-SSD. Hence, the classic suicide prevention model might be of little use for SSD.