The Best Australian Science Writing 2015

by Heidi Norman

  Other species are barely hanging on: some 55 endemic land mammals – 20 per cent of Australia’s total – are threatened with extinction. ‘You look at the outback and see how vast and natural it seems to be,’ says John Woinarski, a conservation biologist at Charles Darwin University (CDU), Casuarina. ‘But we’ve clearly fractured its ecological processes.’

  As losses accumulated in southern and central Australia, the sparsely populated north appeared to offer a safe haven. Bigger than Alaska, the tropical savannas that span parts of Western Australia, the Northern Territory, and Queensland have vast tracts of intact vegetation and, importantly, have proven inhospitable to the red fox. But the sanctuary was illusory. In the late 1980s, when Woinarski began his studies in the Northern Territory, 200 traps would catch 30 or 40 animals overnight. Nowadays, a typical haul is zero. ‘It’s heartbreaking,’ he says. ‘Things that were there a decade before have just disappeared.’

  Feral cats are undeniably the chief culprit. In a paper published online in September 2014 in the Journal of Applied Ecology, Woinarski and colleagues showed that cats unleashed in an experimental enclosure can extirpate the long-haired rat, a native of northern Australia’s savannas. And after dissecting a feral cat shot by a Kakadu ranger, Stokeld found in its stomach the remains of a dusky rat, four grassland mosaic-tailed rats, and two fawn antechinuses, a carnivorous marsupial. The non-profit Australian Wildlife Conservancy (AWC) estimates that every day in Australia, an astounding 75 million animals fall prey to roughly 15 million feral cats. But scientists doubt that the cats, which began fanning out across Australia soon after European settlers first arrived in 1788, are acting alone. The recent declines, says Chris Johnson, an ecologist at the University of Tasmania, Hobart, beg the question, ‘Why now?’

  The answer may be changing fire regimes. Before Europeans arrived, Aboriginal Australians would burn small patches or pathways of bush to create conditions ideal for hunting or for moving more easily through the landscape. As Aboriginal populations dwindled, ‘nastier’ fires that burned hotter and left bigger fire scars became the norm, says Jeremy Russell-Smith, a fire ecologist at CDU. In recent unpublished research using GPS tracking in north-western Australia, Sarah Legge, chief scientist at AWC, revealed that more widespread burning helps feral cats pick off critters exposed by the loss of ground cover.

  To deprive the cats of their hunting grounds, AWC has implemented an intensive fire management regime at the Mornington Wildlife Sanctuary in north-western Australia’s Kimberley region, intended to safeguard unburned vegetation. The reserve has also assiduously culled feral herbivores such as cattle, horses, and donkeys that thin the vegetation. As a result, native rodent and marsupial numbers have shot up fourfold in some habitats over just three years.

  Curtailing feral cat populations is a more formidable challenge. One promising approach is an experimental bait containing para-aminopropiophenone, a chemical that converts haemoglobin in the bloodstream into methaemoglobin, which cannot transport oxygen. In a trial with the bait in central Australia last year, feral cat numbers fell by more than 50 per cent. However, trials in other areas didn’t go so well, perhaps due to a greater abundance of live prey, which the cats favour over bait, or heavy rainfall that dampened the bait’s appeal.

  Some species may end up making their last stands on islands or in mainland arks fenced off from predators. In 2003, 64 captive-bred northern quolls were released on two islands free of cane toads off Australia’s northern coast. A decade on, each island has several thousand quolls, says Dion Wedd, a curator at the Territory Wildlife Park in Berry Springs who was involved in the breeding program. Still, most scientists see such refuges as a last resort. Says Alaric Fisher, an ecologist at the Department of Land Resource Management: ‘We need [approaches] that work outside of fences.’

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  Will a statin a day really keep the doctor away?

  Elizabeth Finkel

  Robert Browning, a California-based CFO of a life science company, is in his late 40s, has never been sick, is not overweight, and works out twice a week. But one day early last year when he went out for a walk he felt a sudden, strong pain in a small area of his right calf muscle. ‘It was as if someone had shot me in the leg,’ he remembers. It was a muscle cramp so severe that he had to sit down, unable to walk or even stand.

  After some research, Browning found that cramps can be a side effect of the only drug he was taking: Lipitor. His doctor had started him on the cholesterol-lowering statin a few weeks earlier after a test showed elevated cholesterol levels, raising his risk of heart attacks and strokes. Browning had never felt anything like that cramp before and was sure it wasn’t related to his exercises. So when another one happened close to the same area two weeks later, he decided to stop the statins for good. He has not had a problem since.

  Plenty of healthy people like Browning have been prescribed statins to lower their cholesterol. Now they are at the centre of a fierce medical debate. On one hand, doctors say cases like Browning’s are common and that debilitating side effects outweigh the benefits. On the other, researchers who analyse studies of hundreds of thousands of people under carefully controlled conditions say most of these ‘side effects’ are not related to statins. In their view, the evidence is in: the benefits of taking statins to prevent coronaries and strokes outweigh the risks.

  It’s far from an academic debate. In 2014 health authorities in Britain and the US recommended widening the use of statins. These recommendations could see most men over 50 taking the drugs, amounting to a billion people worldwide.

  Although statins are going off patent – Lipitor, the most popular, went off patent in 2011 – total revenues will keep rising, reaching one trillion US dollars by 2020 according to an estimate by John Ioannidis, a health policy expert at Stanford University.

  Naturally, many are suspicious that the long arm of drug companies is behind the push to ‘statinise’ much of the world’s population. But many public health specialists believe the costs of widening the use of statins will be repaid in full by lowering the burden of heart attacks and strokes.

  The debate has been explosive, rocking medical circles and reverberating in the media. The Australian TV show Catalyst even retracted two programs on the topic in May 2014. And yet it is nothing new. The debate over whether people should lower their cholesterol levels with statins has been incendiary since the drugs were introduced two decades ago.

  There’s no doubt that by lowering cholesterol levels statins save lives in people with clogged arteries, especially in those who’ve already suffered a heart attack or stroke.

  But why wait: could taking statins prevent the blockage of arteries? Most heart attacks and strokes take place in people who’ve never had a symptom. That compelling logic has seen doctors prescribe statins to healthy people with high cholesterol for more than 20 years.

  Until recently, the recommended threshold for prescribing statins was a 20 per cent risk of having a heart attack or stroke in the next ten years. That figure was based on a formula in which your doctor plugs in your cholesterol levels, blood pressure, smoking history, gender and age. But many doctors found their patients reported side effects – muscle cramps, back pain, nausea, memory loss and more. So was it really worth their while taking the drugs?

  Studies on human beings are notorious for reaching different findings. They may be poorly designed or there may be unseen ‘confounding’ factors. The prime adjudicator is an international group of independent experts who do not take money from the pharmaceutical industry called the Cochrane Collaboration. They slash their way through the academic thicket, decide which studies are worth analysing, and then do a so-called ‘meta-analysis’. Typically, the studies that are selected meet the gold standard: randomised placebo-controlled trials. Patients are randomly assigned to a tr
eatment group that receives the real pill, or to a placebo group that receives a drug-free but otherwise identical pill.

  Until 2011, Cochrane researchers found no clear benefits to using statins for ‘primary prevention’ – in other words, to treating patients with no symptoms of an impending stroke or heart attack. Then in January 2013 they changed their tune.

  Asymptomatic people who took statins were having fewer heart attacks and strokes and were less likely to need surgery to clear blocked arteries. Overall, there were fewer deaths. They concluded: ‘Statins are likely to be cost effective in primary prevention.’

  The summary did not go unheeded. In January 2014 the American Heart Association published its new cholesterol guidelines. While they stressed the role of diet and lifestyle and the need to consider each patient individually, they also lowered the recommended threshold for using statins to a 7.5 per cent risk over the next ten years. Six months later Britain’s National Institute for Health and Clinical Excellence lowered its threshold for treatment from a 20 per cent risk to 10 per cent risk over the next decade. They estimated that even if only two million extra people took the drugs, 4000 heart attack deaths, 14 000 non-fatal heart attacks and 8000 strokes would be prevented – in health economic terms, a good trade-off for the estimated $60 million cost of using the off-patent drugs.

  But not everyone was swayed by the Cochrane Collaboration’s finding.

  ABC TV journalist Maryanne Demasi had been watching with interest. A former PhD medical researcher, she had been researching the topic since 2010. During the filming of a story in a cardiologist’s surgery she’d been astonished to find that a patient with a very high cholesterol level of 9mmol/L was not going to be put on statins. ‘His arteries are clean’, the cardiologist had told her and added: ‘You should do a story on this.’ Demasi started watching the ructions in the medical literature over the role of cholesterol in heart disease.

  The Cochrane review of January 2013 was her lighting rod. It seemed at odds with other evidence that questioned the role of saturated fats and cholesterol in the development of heart disease. She also questioned the wisdom of automatically placing people on statins to reduce that risk. Many of her interviews were carried out with John Abramson, a health care policy lecturer at Harvard Medical School who acts as an expert in legal cases against drug companies for people who believe they have been harmed by statins.

  On October 24, 2013, the first of Demasi’s two-part program ‘The Heart of the Matter’ went to air. The episodes operated like a one-two knock-out punch. The first questioned the evidence that saturated fats and cholesterol were the villains of heart disease. The second challenged the use of statins, especially in people who had not yet suffered a heart attack.

  Watched by one and a half million viewers, Demasi’s program triggered a firestorm. Many in the medical community considered the program had seriously distorted the mainstream view in its first episode, a criticism helped by her choice of ‘experts’. Media Watch, another ABC TV program, weighed in with background checks on them.

  Nutritionist Jonny Bowden who claimed in the program, ‘When you look at the data, it’s very clear – everything that we have been told about saturated fat and cholesterol is a bold-faced lie’, turned out to hold a PhD from the Clayton College of Natural Health, an organisation with questionable credentials. Stephen Sinatra, though a bona fide cardiologist, was also found to be partial to ‘grounding’, the soaking up of electrons from the Earth for better health. The two had co-authored a book titled The Great Cholesterol Myth – why lowering your cholesterol won’t prevent heart disease and the statin-free plan that will.

  The second episode was roundly criticised for failing to spell out that statins have been proven beyond doubt to save lives in people at high risk of heart attacks and strokes.

  Australia’s National Heart Foundation was ‘shocked by the disregard for the extensive evidence’. Emily Banks, chairwoman of the Advisory Committee on the Safety of Medicines, commented to ABC news, ‘there will be people who didn’t have to have a heart attack, who will die through reducing use of statins’.

  It was not an idle claim – studies have shown an increased rate of death in people who discontinue their medication. Banks’ concerns were realised. A National Heart Foundation survey of 1094 Australians conducted a month after the Catalyst program in November 2013 found ‘that more than one in five people on statins who saw the program made a change to their medication. Around a quarter of these people had previously had a heart attack’.

  ‘Serious journalists within the ABC were questioning how a program like that got to air,’ commented Norman Swan, presenter of the ABC’s radio program The Health Report and regular Cosmos contributor.

  On 12 May 2014, the ABC announced it would pull both programs after an independent commission concluded that part two (on statins) had breached the ABC’s impartiality standards. Demasi remained uncowed. She said her intention had been to encourage debate and critical thinking. Though she had weakened her case by giving much of the airtime to fringe players, there’s no doubt she had support from high places – including the British Medical Journal.

  In an extraordinary coincidence, two days before Demasi’s first program went to air the esteemed journal published two articles that supported her take on the subject. The first was an opinion piece from Aseem Malhotra, a cardiology registrar at Croydon University in London. It took up the cause for saturated fats in an article headed, ‘Let’s bust the myth of its role in heart disease’, which challenged the view that a high cholesterol level is a risk for healthy people. The second, by Harvard’s John Abramson and colleagues, challenged the findings of the Cochrane Collaboration. In their view the benefits did not outweigh the risks of treating non-symptomatic people with statins.

  The two BMJ papers created their own firestorm. Malhotra was criticised for taking the same sort of fringe view on cholesterol and saturated fats that Sinatra and Bowden had expressed on Catalyst – one that could lead high-risk patients to stop their medications. But there was a more serious problem.

  Both articles claimed the side effects of statins caused 20 per cent of patients to stop taking the drugs. The figure came from an April 2013 study published in the Annals of Internal Medicine led by Alexander Turchin at Brigham and Women’s Hospital in Boston and his colleagues. In it, about half of the 107 835 subjects stopped taking their statins regularly. But not everyone stopped for a particular medical reason; some people just don’t like to take pills. Turchin’s study was designed to explore whether the side effects from statins were serious enough to cause patients to give up on the drug.

  Overall, he found 17.4 per cent of the entire group reported a side effect – the source of the figure cited by Abramson and Malhotra, who rounded it up to 20 per cent. But only 11 per cent of them actually stopped taking their pills. Turchin’s study also looked more closely at a subgroup of 6500 patients who were encouraged to give statins a second try: 90 per cent of them tolerated the drug, some at lower doses or after trying a different form of statin, and were still taking statins a year later.

  So in fact only 10 per cent of an initial group of refusers could not tolerate the drug. (Applying that fraction to the entire group means that only 10 per cent of the initial 11 per cent fall in this category. In other words, perhaps as few as 1 per cent of people were truly intolerant of statins.) Turchin drew a different conclusion from his findings than Abramson and Malhotra. ‘We interpret these results as a glass half-full, meaning that there are potentially millions of patients who could take statins again, and ultimately reduce their risk of heart disease’, he wrote in a press release. Arguably then, the most informative reading of the study is that it was not 20 per cent who could not tolerate statins, but far fewer.

  Rory Collins, the co-director of Oxford University’s Epidemiological Studies unit, raised the alarm about the BMJ papers arguing that by overstating the true rate of the side effects the articles could influence high-risk patien
ts to stop taking statins. He urged the BMJ to retract both papers. On May 15, 2014, the BMJ agreed to amend the statements about the side effects. It also said it would ask an independent commission to check whether the articles should be retracted.

  Collins had another reason to be chagrined. Abramson had challenged the 2013 Cochrane Collaboration findings. All their previous publications had urged caution in prescribing statins to people at low risk of heart disease and stroke, but then they changed their tune. They did so because of a study led by Collins and his colleague Anthony Keech at the University of Sydney.

  ‘It was this work that set the ball rolling’, says Shah Ebrahim, an author of the Cochrane report. Published in the Lancet in May 2012, the report was based on the Cholesterol Treatment Trialists’ collaboration (CTT). This study of 170 000 patients is the most comprehensive one could imagine on the effects of statins. Begun in 1990, shortly after the introduction of statins, it has collated data on most of the randomised controlled trials of statins in populations around the world for 24 years. Although funded by the drug companies that developed statins, the studies have been run by academic researchers who pool their results, cross-check each other’s analysis and finally report using all the available data. ‘For the last 23 years we’ve met each November with representatives from each of the trials’, explains Keech.

  Studies such as the 1994 Scandinavian Simvastatin Survival Study 4S showed statins reduced deaths in people who had already had a heart attack or stroke or were otherwise at high risk. But over the years the studies tackled different questions: were statins useful for older people, for women, for people with existing diabetes, for people with high blood pressure?

  But what about low-risk people such as Browning? Would they benefit from taking statins? CTT measured the rate of heart attacks, strokes, surgery to unblock arteries, and deaths in such people without evidence of disease. They were compared to a control group who did not take statins. They found that, for every unit of cholesterol lowered, people reduced their risk of a cardiovascular event by about 20 per cent.