Table 1.
Rates of suicide
| Study | Details of study | Population | Conclusion on suicide rates |
|---|---|---|---|
| Phillips et al. (2004) | Retrospective observational study in China. Data for 1995–99 were extrapolated from data obtained from 1993 | Annual estimate of 4.25 million people with schizophrenia and 284,614 total suicides – of which 28,737 suicides are by people with schizophrenia | 10.1% of all suicides had schizophrenia. Suicide rate in adults with schizophrenia was 6.8/1000 people/year. RR of suicide in those with schizophrenia vs. those without is 23.8. |
| Silverton et al. (2008) | 43 year prospective longitudinal Danish cohort study | 208 children in ‘high-risk’ group (based on mother's diagnosis of schizophrenia), 11 committed suicide | Suicide was 14 times more likely in ‘high-risk’ subjects diagnosed with schizophrenia, compared with other mental disorders or no mental disorders |
| Craig et al. (2006) | Prospective cohort study. 5- and 10-year survival; absolute and relative mortality rates among first-admission patients with psychotic disorder | 235 patients with schizophrenia, 12 deaths due to all causes (four natural deaths, seven unnatural death, one unknown) | 1.7% of all patients with schizophrenia died by suicide |
| Ran et al. (2007) | 10-year prospective follow-up study in rural China | 500 patients with schizophrenia; 21 died by suicide | Suicide rate was 477/100000 person-years. SMR was 32.0. Risk of suicide during the follow-up period was 4.5%. |
| Osborn et al. (2008) | Retrospective cohort study in general practices in UK from 1987–2002 | 46,136 patients with severe mental illness (40.2% with schizophrenia) included, matched with 300,426 controls | 48 (0.26%) patients with schizophrenia committed suicide; adjusted hazard ratio = 7.00 |
| Healy et al. (2006) | Retrospective cohort study, North Wales, UK. Compared lifetime suicide rates in treated schizophrenia between cohorts from 1875–1924 and 1994–1998 | 1875–1924: 594 patients with schizophrenia, three suicides 1994–1998: 85 patients, four suicides | 1875–1924: 16/100000 patient-years, lifetime suicide rate of 0.46% 1994–1998: 752/100000 patient-years |
| Nordentoft et al. (2004) | Case-control study using four Danish longitudinal registers from 1981–1997 | 18,744 individuals committed suicide in total, including 756 people with schizophrenia | Suicide rates were found to decline from 1981–1997 by >50%. Incidence rate ratio for suicide among patients with schizophrenia was about 20 times higher than the general population |
| Carlborg et al. (2008) | Follow-up study in Sweden from 1973–2006 | 385 inpatients (153 men, 232 women) with schizophrenia spectrum psychoses | Rate of suicide during the follow-up period was 6.8%. Incidence rate ratio for suicide was 1.01 |
| Bhatia et al. (2006) | Retrospective cohort study with Indian and American samples | 460 Indians and 424 Americans | More attempted suicides in US (205/424 in US vs. 107/460 in India cohorts) |
| Limosin et al. (2007) | 10-year prospective follow-up study in France | 3470 patients with schizophrenia, 141 suicides | Prevalence of suicide (global SMR) was 16.2. Mortality due to suicide especially high during the first 4 years of follow-up |
| Barak et al. (2004a) | 10-year case-control study in Israel | 692 elderly patients with schizophrenia, 30 patients attempted suicide | Rate of suicide attempts was ∼5%, somewhat less than that reported for younger patients |
| Laursen et al. (2007) | Retrospective cohort study using two population-based cohorts in Denmark | Schizophrenia: 17,660 first admissions and 3942 deceased. Schizoaffective: 4055 first admissions and 1261 deaths | Mortality rate ratio for suicide among male and female patients with schizophrenia was 34.51 and 58.81, respectively. Schizophrenia highest mortality rate ratio in the age groups 55–79 and 80+. |
RR, relative risk; SMR, standardised mortality ratio.