NHS privatisation was connected to more than 500 deaths from treatable diseases in England over five years, “devastating” new research by Oxford University has concluded.

The study, funded by the Wellcome Trust and published in The Lancet journal today, is billed as the first full assessment of NHS privatisation in the wake of Andrew Lansley’s 2012 Health and Social Care Act, which encouraged more outsourcing.

The researchers measured how much NHS clinical commissioning groups (CCGs) across England spent on outsourcing from 2013 to 2020, and compared it with how many people died from ‘treatable’ illnesses – meaning deaths considered avoidable with effective healthcare.

On average, they found every additional 1% of annual CCG budgets that went on outsourcing was associated with a rise in treatable mortality of 0.29 deaths per 100,000 population the following year. The researchers say 557 additional deaths during the years 2014 to 2018 might be attributed to changes in outsourcing.

They allowed a year’s lag time for any outsourcing to have an impact on health outcomes.

Whilst the relationship is statistically significant – meaning it is not likely to be down to chance – the researchers said the findings are not evidence of a causal relationship between outsourcing and mortality rates, meaning other factors may also be involved. They adjusted the data for changes to population, demographics and poverty levels.

It is not known if particular types of outsourced provision have a specific impact on treatable mortality.

Dr Aaron Reeves of Oxford University, who co-authored the study, said: “These results clearly have implications for the NHS privatisation debate, suggesting that increased outsourcing to the private sector could lead to a decline in the quality of care provided to patients.

“While more research is needed to determine the precise causes of the declining quality of healthcare in England, our findings suggest that further increases in NHS privatisation would be a mistake.”

The study calculated a relationship between outsourcing and treatable mortality across the English NHS, although figures for individual CCGs varied significantly.

East Staffordshire CCG saw a 29% rise in outsourced spending between 2014 and 2017, with a 9% rise in treatable mortality between 2015 and 2018. Greater Huddersfield CCG saw a 13% rise in treatable mortality in the wake of a 4% increase in outsourced spending, while Sandwell and West Birmingham CCG saw a 5% rise in treatable mortality following a 4% rise in outsourcing.

Cat Hobbs, director of anti-privatisation campaign group We Own It, told openDemocracy: “This devastating study demonstrates a trend we have seen across the world – wherever privatisation is introduced, healthcare gets less equal and public health suffers.

“Privatisation and outsourcing in our NHS has been disastrous for patients. It isn’t just inefficient and wasteful, it can literally be the difference between life and death. This is unsurprising when you look at mortality rates in America where privatisation is further advanced.

“It's time for the government to stop risking lives in their ideological pursuit of privatisation and commit to reinstating the NHS as a fully public and properly funded service. Our healthcare system must work for people, not profit.”

The research found overall levels of NHS outsourcing in England rose steadily during the period, from less than 4% (£576m out of £14.8bn from April to December 2013) to more than 6% (£2.6bn out of £40.6bn in 2019) of annual CCG spending.

While the biggest percentage increases were on private sector provision of business and IT support, nearly three-quarters of all NHS private sector outsourcing is in healthcare services, spending on which rose by £1bn between 2014 and 2019 – around two-thirds of the total rise in private sector outsourcing.

A spokesperson for the Department of Health and Social Care said: “As the authors make clear, this analysis is not able to identify a causal link between mortality rates and the outsourcing of health services.

“The NHS will always be free at the point of use and will never be for sale to the private sector, and there has been essentially no proportional increase in NHS spending with non-NHS providers over the last decade.“

East Staffordshire CCG have been approached for comment. Greater Huddersfield CCG and Sandwell and West Birmingham CCG have since been merged into other CCGs, all of which are set to be replaced by Integrated Care Systems under a new NHS reorganisation.