The UK has fallen behind its European neighbours in preventing deaths among children and young adults, dropping from among the best performers in 1970s to one of the worst today.

In figures which add to mounting evidence of the UK’s dire record on child mortality, researchers found that improvements in the death rate among children under nine had been particularly slow.

High numbers of premature births, which are linked to smoking and obesity, were partly to blame, the study said.

By 2008, researchers estimated, there were 1,035 additional deaths among children under one year old compared to the average among for the country’s surveyed, which included 18 rich European nations, as well as Australia and Canada.

Among young people, unusually high numbers of deaths from illnesses related to drug misuse, as well as poor performance in caring for patients with long-term conditions such as diabetes, asthma and psychiatric disorders, contributed to the UK’s poor performance.

The findings, based on an analysis of the World Health Organisation’s World Mortality Database, and published in The Lancet medical journal, add to recent evidence that the UK’s child mortality rate is the second-worst in western Europe.

Both studies identified higher levels of child poverty and economic inequality in the UK as key factors behind its declining performance.

The new study, carried out by experts at University College London, also highlighted that problems in the UK’s healthcare system may be a factor – a reference to longstanding concerns that the NHS performs poorly in terms of caring for patients with long-term health conditions.

Dr Hillary Cass, president of the Royal College of Paediatrics and Child Health said that while Government action to close the gap between rich and poor was important, healthcare professionals could not “shy away” from responsibility.

“We need to take steps such as making sure every child with a condition such as asthma and epilepsy has a dedicated plan, ensuring all healthcare professionals are confident and competent in recognising a sick child and providing better support to mothers to reduce risky behaviours during pregnancy – including smoking – which impacts the health of new-borns,” she said.