Sex, timing, and depression among suicide victims with schizophrenia

Schizophrenia and depression by themselves and especially in combination with each other are known to be important risk factors of suicide. An increased risk of suicide has also been reported for the period immediately after a psychiatric patient's discharge from the hospital. However, to the best of our knowledge, it remains unknown whether survival times differ between suicide victims with schizophrenia concomitantly with and those without depression.

This study aimed to examine survival times from the discharge of last hospital treatment (irrespective of the kind of illness) to the day of death in suicide victims with schizophrenia with or without concomitant depression.

A 16-year database of all suicides (1535 males, 342 females) committed during the years 1988-2003 in the province of Oulu in northern Finland, and information available from the national hospital discharge registers formed the basis of this study.

In male suicide victims with schizophrenia, the median survival time after final hospitalization was approximately 1 day in those with a history of depression and 90 days in those without depression (P = .005). The corresponding times for females were 50 and 24 days, respectively (P = .396). Using Cox regression analysis after adjusting for confounders, we noticed a statistically significant difference in survival times from last hospitalization to suicide between depressive and nondepressive male patients with schizophrenia (hazard ratio, 1.80; 95% confidence interval, 1.04-3.11), but not females (hazard ratio, 0.72; 95% confidence interval, 0.34-1.53).

Concomitant depression was markedly linked with shorter survival time in male suicide victims with schizophrenia after last hospitalization. Psychiatric inpatient facilities appear to be in a key position to establish suicide prevention programs for patients with schizophrenia, especially those with depression.