Australian scientists found the suicide rate in the country increased significantly when a Conservative government was in power.

And an analysis of figures in the UK seems to suggest a similar trend.

The Australian team analysed suicide statistics for New South Wales between 1901, when the federal government was established, and 1998.

They then looked at the political regimes dominating both state and federal governments in New South Wales, which have consistently been under either Labour or Conservative control.

The researchers took into account periods of drought and World War II, because of their economic and psychological impact.

Suicide rates were higher during periods of drought and lower during WWII.

But after adjusting for these factors, the figures clearly showed the highest rates of suicide occurred when both Conservative state and federal governments were in power.

Men at risk

Conversely, the lowest rates occurred when state and federal governments were both Labour.

Middle aged and older people were most at risk.

When the Conservatives ruled both state and federal governments, men were 17% more likely to commit suicide than when Labour was in power. Women were 40% more likely to kill themselves.

Suicide rates were higher under post-war than pre-war Conservative governments.

The rate dipped under moderate John Major

The authors argue that Conservative rule traditionally implies a less interventionist and more market-orientated policy than Labour rule.

This may make people feel more detached from society, they added.

The researchers concede that ideological distinctions between Conservative and Labour politicians have become more blurred over the past 20 years.

But they say public perceptions that their policies differ may still remain intact.

Lead researcher Professor Richard Taylor, of the University of Sydney, told BBC News Online: "We think that it may be because material conditions in lower socio-economic groups may be relatively better under labour because of government programmes, and there may be a perception of greater hope by these groups under labour.

"There is a strong relationship between socio-economic status and suicide."

The research is published in the Journal of Epidemiology and Community Health.

British situation

In one of a series of accompanying editorials, Dr Mary Shaw and colleagues from the University of Bristol say the same patterns were evident in England and Wales between 1901 and 2000.

Rates have been lower under Labour governments and soared under the last Conservative regime, which began in 1979 under Margaret Thatcher.

They fell under 'the more moderate' John Major and after a slight rise when Tony Blair came to power, have since fallen again.

Interestingly, the authors point out that although suicide rates tend to increase when unemployment is high, they were also above average during the 1950s when Britain "never had it so good," but was ruled by the Conservative party.

Overall, they say, the figures suggest that 35,000 people would not have died had the Conservatives not been in power, equivalent to one suicide for every day of the 20th century or two for every day that the Conservatives ruled.

The UK Conservative Party refused to comment on the research.