Could pills for heartburn give you kidney problems?

When heartburn strikes, it’s tempting to reach for a drug to relieve the unpleasant burning chest pain. But a mounting body of research suggests that pills taken by millions to relieve acid reflux come with their own worrying health effects.

The latest finding shows a link with serious kidney disease.

The pills, known as proton pump inhibitors (PPIs), are available on prescription and over the counter under brand names including Prilosec, Prevacid and Zegerid.

In 2014, there were 53 million prescriptions for PPIs, such as omeprazole and lansoprazole, in england alone. Last year, a major study found people taking certain PPIs had a 20 per cent greater risk of heart attack — even if they were otherwise healthy.

Previous studies also suggested that using the medication for more than a year could lead to a dangerous deficiency in vital nutrients and raise the risk of the deadly infection C. difficile.

The drugs are used to treat gastroesophageal reflux disease, or reflux. This occurs when stomach acid escapes into the gullet, causing burning pain.

The number of people affected is rising sharply, possibly because of poor diets and obesity, which puts pressure on the valve that keeps the stomach contents out of the gullet.

PPI drugs block the enzymes that make stomach acid, so you produce just 10 per cent of normal levels.

This is different from antacids, such as Rennies or Gaviscon, that coat the stomach contents, stopping acid rising into your gullet and causing heartburn.

however, according to scientists at houston Methodist hospital, as well as blocking acid production, PPIs cut supplies of nitric oxide, a natural substance that’s vital for relaxing blood vessels.

This may be why PPIs are linked to heart attacks, as they may make high blood pressure more likely.

Research by Stanford University, of nearly three million patients with serious heartburn, found that those on PPIs had a significantly greater risk of a heart attack than those on other antacid medication.

The findings supported a ten-year study published in the British Medical Journal in 2011, which found that patients taking PPIs had a raised risk of heart attack.

experts stress this does not prove the drugs caused the attacks — it could be that those getting the stronger PPIs were more sick and so at greater risk of heart problems anyway. ‘no one should stop taking the drugs as a result of this study,’ says heart surgeon Dr nicholas Leeper, who led the study.

The new research that uncovered the risk to kidneys was done at the prestigious Johns hopkins University, Baltimore, Maryland, and involved tracking thousands of patients with cardiovascular disease for 14 years.

As well as drugs to lower blood pressure and cholesterol, some took PPIs to protect against bleeding in the stomach that can be caused by aspirin taken for heart protection.

Those on PPIs were 15 per cent more likely to develop chronic kidney disease over ten years.

This follows a warning in 2010 from the national Prescribing Centre that PPIs raise the risk of a dangerous C. difficile infection, which claims 2,000 lives a year.

Stomach acid acts like a disinfectant, preventing bugs from flourishing in our gut. Reducing stomach acid with PPIs lowers this protection. Yet studies show 46 per cent of hospital patients are on PPIs.

‘These drugs are far too widely used and half those patients aren’t taking them for any good reason,’ says Dr Richard Cunningham, a consultant microbiologist at Derriford hospital, Plymouth.

The national Institute for health and Care excellence (NICE) tells doctors the conditions they should prescribe PPIs for — these include acid reflux and peptic ulcers.

‘however, it is routinely ignored,’ says Dr Cunningham. ‘Many doctors don’t seem to be aware that using the drugs to cut the risk of bleeding from ulcers is not on the list.’

Some scientists warn that the effect PPIs can have on friendly bacteria in our gut may cause the drugs’ dangerous side-effects.

‘These microbes have a much more important role in human health than previously thought,’ says Professor Tim Spector, a gastroenterologist at King’s College London.

In December, his team published research showing PPIs can cause a drop in the number of beneficial bacteria in the gut and an increase in ones found in the mouth and nose that cause infections.

Chronic kidney disease has been linked with changes in the balance of bacteria in the gut. As well as kidney and heart disease, and bacterial infections, a link with hip fractures has emerged.

PPIS are often given to patients with heartburn from bi s phosphonate drugs, which are used to treat osteoporosis.

however, PPIs can also reduce bisphosphonates’ effectiveness to zero, according to a 2011 study in the Archives of Internal Medicine. If you are at risk of brittle bones and take a PPI, ask your doctor to check your calcium levels.

What is not clear is whether taking lower- dose over-the- counter PPIs would reduce these risks. But experts agree that people should not stop taking prescription PPIs without advice.

‘For most, these drugs are safe,’ says Dr Anton emmanuel, consultant gastroenterologist at University College hospital, London.

‘But the data shows a risk of kidney impairment, osteoporosis and C. diff infections in patients taking high doses for long periods.

‘It’s important not to rely on them as regular treatment, and to take the lowest dose you can get away with.’