Common medicines used to treat conditions including heartburn, reflux, indigestion and stomach ulcers may be the subject of a class action lawsuit in Australia.

Lawyers are exploring whether long-term use of these over-the-counter and prescription drugs are linked to stomach cancer or kidney disease.

The potential class action follows the settlement of a related multi-million dollar lawsuit in the United States. Last year, international pharmaceutical company AstraZeneca settled for US$425 million (A$637 million) after patients made the case that two of its drugs caused significant and potentially life-threatening side effects.

Specifically, patients claimed the company’s drugs Nexium (esomeprazole) and Prilosec (omeprazole) increased the risk of kidney damage.

Which drugs are involved in Australia?

The class of drugs we’re talking about are “proton pump inhibitors” (sometimes called PPIs). In the case of the Australian potential class action, lawyers are investigating:

• Nexium (esomeprazole)
• Losec, Asimax (omeprazole)
• Somac (pantoprazole)
• Pariet (rabeprazole)
• Zoton (lansoprazole).

Depending on their strength and quantity, these medicines are available over-the-counter in pharmacies or by prescription.

They have been available in Australia for more than 20 years and are in the top ten medicines dispensed through the Pharmaceutical Benefits Scheme.

They are used to treat conditions exacerbated by stomach acid. These include heartburn, gastric reflux and indigestion. They work by blocking the protein responsible for pumping acid into the stomach.

These drugs are also prescribed with antibiotics to treat the bacterium Helicobacter pylori, which causes stomach ulcers and stomach cancer.

What do we know about the risks?

Appropriate use of proton pump inhibitors plays an important role in treating several serious digestive problems. Like all medicines, there are risks associated with their use depending on how much and how long they are used.

When proton pump inhibitors are used appropriately for the short-term treatment of stomach problems, they are generally well tolerated, safe and effective.

Their risks are mostly associated with long-term use (using them for more than a year) due to the negative effects from having reduced levels of stomach acid. In elderly people, these include an increased risk of gut and respiratory tract infections, nutrient deficiencies and fractures. Long-term use of these drugs in elderly people has also been associated with an increased risk of dementia.

In children, there is an increased risk of serious infection associated with using these drugs, regardless of how long they are used.

How about the cancer and kidney risk?

Currently, the Australian consumer medicine information sheets that come with the medicines, like this one for esomeprazole, do not list stomach cancer or kidney injury as a risk associated with using proton pump inhibitors.

So what does the evidence say about the risk?

Over the past few years, there have been large studies based on observing people in the general population who have used proton pump inhibitors. These studies have found people who take them are almost two times more likely to develop stomach cancer and 1.7 times more likely to develop chronic kidney disease when compared with people who are not taking them.

In particular, these studies report that users of the drugs lansoprazole and pantoprazole have about a three to four times higher risk than non-users of developing chronic kidney disease.

While these observational studies show a link between using the drugs and these outcomes, we cannot say from this evidence that one causes the other.

What can I do if I’m worried?

Several digestive conditions, especially reflux and heartburn, may benefit from simple dietary and lifestyle changes. But the overall evidence for these is not strong and how well they work varies between individuals.

But it may help to avoid large meals within two to three hours before bed, and reduce your intake of fatty food, alcohol and coffee. Eating slowly and getting your weight down if you are overweight may also help your symptoms.

There are also medications other than proton pump inhibitors that can be used for heartburn, reflux and stomach ulcers.

These include over-the-counter antacids (such as Gaviscon and Mylanta), which work by neutralising the acidic environment of the stomach.

Alternatives for prescription drugs include nizatidine and famotidine. These work by blocking histamine receptors in the stomach, which decreases stomach acid production.

If you are concerned about your use of proton pump inhibitors it is important to speak with your doctor or pharmacist before you stop using them. That’s because when you have been using them for a while, stopping them may result in increased or “rebound” acid production.

Nial Wheate, Professor and Director – Academic Excellence, Macquarie University; Joanna Harnett, Senior Lecturer – Sydney Pharmacy School, Faculty of Medicine and Health, University of Sydney, and Wai-Jo Jocelin Chan, Pharmacist and Associate Lecturer, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

People have a pretty intuitive sense of what is healthy – standing is better than sitting, exercise is great for overall health and getting good sleep is imperative.

However, if exercise in the evening may disrupt our sleep, or make us feel the need to be more sedentary to recover, a key question emerges – what is the best way to balance our 24 hours to optimise our health?

Our research attempted to answer this for risk factors for heart disease, stroke and diabetes. We found the optimal amount of sleep was 8.3 hours, while for light activity and moderate to vigorous activity, it was best to get 2.2 hours each.

Finding the right balance

Current health guidelines recommend you stick to a sensible regime of moderate-to vigorous-intensity physical activity 2.5–5 hours per week.

However mounting evidence now suggests how you spend your day can have meaningful ramifications for your health. In addition to moderate-to vigorous-intensity physical activity, this means the time you spend sitting, standing, doing light physical activity (such as walking around your house or office) and sleeping.

Our research looked at more than 2,000 adults who wore body sensors that could interpret their physical behaviours, for seven days. This gave us a sense of how they spent their average 24 hours.

At the start of the study participants had their waist circumference, blood sugar and insulin sensitivity measured. The body sensor and assessment data was matched and analysed then tested against health risk markers — such as a heart disease and stroke risk score — to create a model.

Using this model, we fed through thousands of permutations of 24 hours and found the ones with the estimated lowest associations with heart disease risk and blood-glucose levels. This created many optimal mixes of sitting, standing, light and moderate intensity activity.

When we looked at waist circumference, blood sugar, insulin sensitivity and a heart disease and stroke risk score, we noted differing optimal time zones. Where those zones mutually overlapped was ascribed the optimal zone for heart disease and diabetes risk.

You’re doing more physical activity than you think

We found light-intensity physical activity (defined as walking less than 100 steps per minute) – such as walking to the water cooler, the bathroom, or strolling casually with friends – had strong associations with glucose control, and especially in people with type 2 diabetes. This light-intensity physical activity is likely accumulated intermittently throughout the day rather than being a purposeful bout of light exercise.

Our experimental evidence shows that interrupting our sitting regularly with light-physical activity (such as taking a 3–5 minute walk every hour) can improve our metabolism, especially so after lunch.

While the moderate-to-vigorous physical activity time might seem a quite high, at more than 2 hours a day, we defined it as more than 100 steps per minute. This equates to a brisk walk.

It should be noted that these findings are preliminary. This is the first study of heart disease and diabetes risk and the “optimal” 24 hours, and the results will need further confirmation with longer prospective studies.

The data is also cross-sectional. This means that the estimates of time use are correlated with the disease risk factors, meaning it’s unclear whether how participants spent their time influences their risk factors or whether those risk factors influence how someone spends their time.

Australia’s adult physical activity guidelines need updating

Australia’s physical activity guidelines currently only recommend exercise intensity and time. A new set of guidelines are being developed to incorporate 24-hour movement. Soon Australians will be able to use these guidelines to examine their 24 hours and understand where they can make improvements.

While our new research can inform the upcoming guidelines, we should keep in mind that the recommendations are like a north star: something to head towards to improve your health. In principle this means reducing sitting time where possible, increasing standing and light-intensity physical activity, increasing more vigorous intensity physical activity, and aiming for a healthy sleep of 7.5–9 hours per night.

Beneficial changes could come in the form of reducing screen time in the evening or opting for an active commute over driving commute, or prioritising an earlier bed time over watching television in the evening.

It’s also important to acknowledge these are recommendations for an able adult. We all have different considerations, and above all, movement should be fun.

Christian Brakenridge, Postdoctoral research fellow at Swinburne University Centre for Urban Transitions, Swinburne University of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.