If these results can be generalised then virtually all mental disorders have an increased risk of suicide excepting mental retardation and dementia. The suicide risk is highest for functional and lowest for organic disorders with substance misuse disorders lying between. However, within these broad groupings the suicide risk varies widely.

All mental disorders have an increased risk of premature death.

Some of the excess mortality of schizophrenia could be lessened by reducing patients' smoking and exposure to other environmental risk factors and by improving the management of medical disease, mood disturbance and psychosis.

Historically, doctors have not always acknowledged that they have an obligation to prevent suicide, partly because they shared the prevalent idea that most suicides were caused by moral crises, no concern of theirs—and indeed suicide was a criminal matter until quite recently; but more, perhaps, because a fatalism has characterized their attitudes to its prevention, even where the suicide was clearly suffering from mental illness. Yet two recent American studies have shown more than 90 per cent of suicides to be mentally ill before their death (17, 8); this finding and the familiar clinical observation that suicidal thoughts disappear when the illness is successfully treated provide a strong case for a medical policy of prevention.

The lifetime suicide risk figures often quoted in the literature appear to be too high.