To the Editor: Between 1997 and 2006, suicide rates fell in all mainland Australian states and territories.1 Despite a rise in the small-population jurisdictions of Tasmania (1997–2006)1 and an earlier rise in the Northern Territory (1981–2002),2 the overall unadjusted national suicide rate has fallen steadily, from 14.7 per 100 000 in 1997 to 9.06 per 100 000 in 2006, the year for which the most recent statistics are available.

Trends in suicide occurrence are usually examined with reference to suicide rates. However, because there has been population growth in all parts of Australia, examination of the actual number of suicide deaths in each region is also useful to ascertain whether the demographic changes accompanying population growth can alter unadjusted suicide rates.

Annual suicide mortality statistics by state and territory from 1975 to 20061,3,4 show that the number of suicides peaked in every mainland state in 1997 or 1998. Since then, the number of suicides has fallen in New South Wales by 46.5%, in Victoria by 33.5% and in Queensland by 36.4% (Box). There has been larger variation in the number of suicides over time in NSW than in other states. Suicides in NSW rose from under 600 per year (approximately 11 per 100 000 population) in the early 1980s to a peak of 935 suicides in 1997 (14.9 per 100 000) and then fell to 504 suicides (7.4 per 100 000) in 2006. Data available to 2002 indicate that the decline in suicides occurred in almost every NSW health service area and was mainly due to a reduction in the number of suicide deaths in males, including young males.5 By 2006, NSW had the lowest suicide rate in Australia of 7.69 per 100 000 compared with 9.73 per 100 000 for other states and territories.

The reasons for the steeper rise and subsequent fall in suicide in NSW compared with other states are unclear, but warrant further investigation with a combined clinical and epidemiological approach. The decline in suicide in NSW coincided with a change to the Mental Health Act 1990 in 1997 that broadened criteria for involuntary care and allowed more people to be treated. However, this factor alone would not explain the extent of the decrease nor the continued decline over a decade. It is possible that programs to prevent suicide or measures to improve access to psychiatric care in NSW have been more successful than those in other parts of Australia.

Annual number of suicides in Australian states and territories, 1975–2006*

* Data are from the Australian Bureau of Statistics.1,3,4