Spending cuts to health and social care since 2010 are linked to nearly 120,000 extra deaths in England, with over 60s and care home residents worst affected, according to the first study of its kind, published in the journal BMJ Open.

The research suggests that a change in nurse numbers may have played a key role in these excess deaths. The authors warn that if current trends continue, there could be an additional toll of up to 100 excess deaths every day from now onwards – equivalent to around 150,000 people between 2015 and 2020.

They estimate that an additional £6.3bn a year would need to be pumped into the NHS to plug this "mortality gap".

Despite rising demand and healthcare costs, the NHS in England only received a yearly increase in its budget of 1.3% between 2010 and 2014.

In this period, real term spending on social care has fallen by around 1.2% a year. This comes as the number of over 85s – those most likely to need social care – is projected to significantly increase from 1.6 million in 2015 to 1.8 million in 2020.

For the latest study, researchers from University College London tried to address the potential impact on public health from these spending gaps.

To do this, they examined national data on population deaths, life expectancy and potential years of life lost, as well as the finances and resources available to the NHS between 2001 and 2014.

They then compared actual death rates between 2011 and 2014 with those that would be expected based on trends before spending cuts came into play, taking into account national and economic factors, such as unemployment rates and pensions.

The results showed that between 2001 and 2010, deaths in England fell by around 0.77% per year, but rose an average of 0.87% every year between 2011 and 2014. Cuts imposed after 2010 were associated with around 45,000 excess deaths between 2010 and 2014 compared with equivalent trends in the previous decade.

Combining these projected excess deaths and the observed deaths prior to 2015 translates to around 120,000 excess deaths from 2010 to 2017.

Many of these deaths were among over 60s and care home residents. The researchers calculated that every £10 drop in spending per head on social care resulted in five extra care home deaths per 100,000 of the population.

The researchers argue that a slowdown in nurse numbers could be a factor in many of these deaths. From 2010 to 2014, nurse numbers rose by just 0.07% - around 20 times slower than the previous decade.

While this is an observational study, meaning no concrete conclusions can be drawn about cause and effect, the findings echo similar research in this area, according to the researchers.