Expenditure on our health services in the UK has been rising consistently at around 4% per year in real terms for the last 30 years. It has doubled in real terms in just over 10 years. If this trend continues, this would mean us spending the real term equivalent of £230 billion in 2030, which would be 18% of current gross domestic product (GDP) and over double our present expenditure. Most developed countries follow a remarkably similar trend, with the United States well ahead, and Canada, France, and Germany also consistently above the UK.

The proportion of GDP spent on health has also steadily risen, with richer countries generally spending the largest proportion of their GDP. In the US, the average yearly increase in % GDP over the last 50 years has been 0.24, reaching 17.4% in 2009.

There is no obvious reason as to why a society that becomes wealthier—and therefore is able to increase “discretionary” spending—should not spend 30% or more of its GDP on health. However, continued steady economic growth seems unlikely at the moment, and it would probably be impossible to finance such spending levels through taxation.

The main cause of the spending increase has been advances in medical technology. For example, 30 years ago heart attacks were treated with painkillers, aspirin, and betablocking drugs. Since then we have moved on to clot busting drugs and, more recently, to angioplasty, which requires a well staffed catheter lab on call 24/7. Similar trends apply to most areas of medical care, and there is no sign of a slowdown.

Added to this is the effect of the increasingly ageing population. The number of people older than 85 will double in the next 20 years and reach 5% of the population by 2034. The same trend will place pressure on the social care budget, as more people need residential care or home help.

The current and the previous government attempted to deal with these pressures by creating an internal market in the NHS, and encouraging (with huge amounts of money) new providers of both specialist and GP services to enter the market, in the hope that competition would increase efficiency, which is generally accepted to be far from optimal.

The fact that this meant setting up two new sets of administrators in each area—one at the hospitals to send the bills out to the purchasers, and one at the purchasers to check those bills and pay them—was accepted as a necessary cost. The purchasers started as health authorities, which were replaced by primary care trusts, which tried and failed to develop “practice based commissioning,” and which has now been replaced by clinical commissioning groups, but by and large it has been plus ça change.

The intention has been that purchasers would limit demand by controlling referrals and also hold the providers to account. This was always going to be a big ask, as this is the very thing that health insurers in the US and Europe have been trying and failing to do for years. The obvious problem is that any provider hospital that is threatened with a lack of referrals finds it easy to create demand by internal referrals and extra procedures.

In the US in particular, it has become clear that the healthcare market is a very odd form of market, in that the availability of “goods”—in this case medical procedures—actually creates their own demand. It is very difficult for a purchaser to control activity without risking patients being harmed and (more importantly) adverse headlines, especially for investigations and acute procedures, such as angiography. And if there is one thing that modern bureaucracies hate, it is blame. So it is not surprising that, according to the Office for National Statistics, productivity in the NHS fell on average by 0.3% per year between 1995 and 2008.

When in a hole, it is generally a good idea to stop digging. We have had several years of market based reforms to the NHS, which have failed to improve cost effectiveness. To expect that “trying harder” in the same direction will deliver the goods seems more a political dogma than a realistic expectation.

As a GP who has worked in the NHS for over 20 years—and also in Denmark, New Zealand, and South Africa—I think it is vital that we preserve the aspects of the NHS that really are envied by the rest of the world, and which have been emphasised recently by the Commonwealth Fund and the Organisation for Economic Co-operation and Development. These aspects are a coordinated primary care system, which has the trust and confidence of patients, and a lack of conflicts of interest when doctors advise patients. These would be threatened by yet more market based reforms.

Difficult decisions will have to be taken to cope with financial constraints in the years ahead. But working together is the only way that the NHS is going to survive for the next 20 years.

Ted Willis is currently a GP in Brigg, North Lincolnshire. He has also worked in Denmark, Scotland, Zambia, South Africa, and New Zealand. He is interested in health economics and the amazing inefficiency of many healthcare systems.

Competing interests: I am a GP partner, and at the age of 59, I am likely to need the NHS for a little while yet.