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30 October 2012, 6.08am AEST

Explainer: what are phobias?

What makes a fear a phobia? jasonbolonski/Flickr.

A life without fear sounds idyllic but it would be no paradise. Fear protects us from present danger, alerts us to future threat, sharpens our minds and blunts our selfishness. Friedrich Nietzsche once said that fear is the mother of morals, and people who lack it do indeed tend to be nasty, brutish and short-lived.

While useful to a point, people often suffer from an excess of fear. Although many of us are afraid of snakes, spiders, heights and blood, when these normal fears are taken to extremes they become phobias.

To qualify as a phobia, a fear must be lasting, intense and seen by the sufferer as excessive and irrational. It must also be a source of distress or impairment in the person’s occupational life and social relationships.

Phobias affect about 10% of the general population at some point in their lives, with women affected twice as commonly as men.

What are we afraid of?

Phobias commonly involve objects and situations that were realistic dangers for our distant ancestors: poisonous or vicious animals and invitations to injury. As a result, many people are terrified of things that no longer pose a contemporary threat.

Ancestral fears are learnt with remarkable ease. One study found that young rhesus monkeys acquired a fear of snakes when they viewed a film of older monkeys acting terrified in the presence of a snake, but did not come to fear flowers when they viewed monkeys going ape in the presence of a blossom. Fears related to things that were threats to our forebears are more easily acquired than others.

Deliciously scary? EuroMagic/Flickr.

Although many common phobias are of this ancient or “prepared” kind, the spectrum of human fears is astonishingly broad. The clinical literature records phobias of rubber bands, dolls, clowns, balloons, onions, being laughed at, dictation, sneezing, swings, chocolate and the wicked, beady eyes of potatoes. Unusual fears are particularly common among people with autism, who have been known to dread hair dryers, egg-beaters, toilets, black television screens, buttons, hairs in the bathtub and facial moles.

It is hard to see the evolutionary threat posed by these innocuous things. As Stanley Rachman, the psychologist who treated the chocophobe wrote, “it is difficult to imagine our pre-technological ancestors fleeing into the bushes at the sight of a well-made truffle”.

How do phobias develop?

Given that many modern phobias make little logical sense, it is interesting to explore how they emerge. There are three main identified ways that phobias come about: a terrifying personal encounter, witnessing another person’s fright, and receiving threatening information. A person might acquire a spider phobia after a close encounter in the shower, after seeing a sibling run screaming from an infested room or after being told that spider bites cause you to turn purple and die.

Only a small minority of people will develop phobias after common experiences such as these. Those who had inhibited temperaments in childhood and neurotic personalities in adulthood are more vulnerable, and this vulnerability has a substantial genetic component.

A study that followed a sample of young women over a 17-month period found that those who developed phobias tended to have more pre-existing psychological problems, poorer coping skills and a more pessimistic mindset than their peers.

Let’s consider one odd but surprisingly common aversion, the fear of frogs.

One published case documented a woman who developed ranidaphobia, as it is known, after running over a knot of frogs with a lawn-mower. Paralysed by fear and tormented by amphibian dreams, she was persecuted every evening by an accusing chorus of survivors on a nearby riverbank.

In another case, a Ghanaian schoolboy developed his phobia when he stepped on a frog while touching itchy leaves. After his brother told him that frog urine could cause itching and a painful death, the boy became paralysed with the fear that frogs were hiding in his bed.

This fear was put to productive use elsewhere in west Africa, with one anthropologist reporting that bed-wetting children were frightened into bladder control by having a live frog attached to their waists.

Ranidaphobia is surprisingly common. Ltshears/Wikimedia Commons.

What gives these puny creatures – with big eyes and scrawny, hairless bodies – their power to inspire fear and trembling? They pose no realistic threat to life: phobic individuals understand that in an encounter with a frog they are unlikely to be the one to croak.

The fear of frogs is viscerally unreasonable. To many people it reflects the frog’s slimy, skin-crawling ickyness. To others, it is the creature’s propensity for sudden movement, a trait it shares with another tiny source of terror, the mouse.


Luckily for phobia sufferers, treatment is generally quick and effective. Cognitive-behaviour therapists have an assortment of techniques for confronting fears and challenging the avoidance and thinking biases that sustain them. Usually these methods involve progressive exposure to the feared object or situation up the steps of a “fear hierarchy”, from relatively nonthreatening encounters to the most terrifying.

These “behavioural experiments” are often supplemented by relaxation techniques, modelling of exposure by the therapist and correction of catastrophic thoughts.

In another case of ranidaphobia, a young nursing student, fainted in a biology class when her laboratory partner severed a frog’s spinal cord (“pithing”). A course of therapy was commenced in which she repeatedly viewed a videotape of the operation and practised relaxation techniques.

Such was the success of the treatment that in a single sitting immediately afterwards she was able to deliver electric shocks to one frog, pith another and cut open the abdomen of an anaesthetised rat, remaining calm even when one frog hopped loose, bleeding profusely from its injuries.

By facing what we dread, under the guidance of a psychologist, we can find freedom from irrational fear.

Why do I gain weight in the Menopause?

Climacteric. 2012 Oct;15(5):419-29.

Understanding weight gain at menopause.


Women’s Health Research Program, Department of Epidemiology and Preventive Medicine, Monash University , Melbourne , Australia.


ABSTRACT Objective The aim of this review was to summarize the literature regarding the impact of the menopause transition on body weight and body composition. Methods We conducted a search of the literature using Medline (Ovid, 1946-present) and PubMed (1966-2012) for English-language studies that included the following search terms: ‘menopause’, ‘midlife’, ‘hormone therapy’ or ‘estrogen’ combined with ‘obesity’, ‘body weight’ or ‘body composition’. Results Whereas weight gain per se cannot be attributed to the menopause transition, the change in the hormonal milieu at menopause is associated with an increase in total body fat and an increase in abdominal fat. Weight excess at midlife is not only associated with a heightened risk of cardiovascular and metabolic disease, but also impacts adversely on health-related quality of life and sexual function. Animal and human studies indicate that this tendency towards central abdominal fat accumulation is ameliorated by estrogen therapy. Studies mostly indicate a reduction in overall fat mass with estrogen and estrogen-progestin therapy, improved insulin sensitivity and a lower rate of development of type 2 diabetes.

Conclusion The hormonal changes across the perimenopause substantially contribute to increased abdominal obesity which leads to additional physical and psychological morbidity. There is strong evidence that estrogen therapy may partly prevent this menopause-related change in body composition and the associated metabolic sequelae. However, further studies are required to identify the women most likely to gain metabolic benefit from menopausal hormone therapy in order to develop evidence-based clinical recommendations.

Ethics of Overdiagnosis

19 September 2012, 6.46am AEST

The ethics of over-diagnosis: risk and responsibility in medicine

OVERDIAGNOSIS EPIDEMIC – Today, Stacy Carter presents a philosophical view of over-diagnosis and what can be done to change how things stand. Recently a friend told me a story about her dad. Fit and well, he had a PSA test during a general medical check-up. The PSA test is controversial: many, including…

Over-diagnosis and over-treatment happen for many reasons – and consumers contribute as well.

OVERDIAGNOSIS EPIDEMIC – Today, Stacy Carter presents a philosophical view of over-diagnosis and what can be done to change how things stand.

Recently a friend told me a story about her dad. Fit and well, he had a PSA test during a general medical check-up. The PSA test is controversial: many, including its inventor, say it should never be used to screen for cancer.

My friend’s dad’s PSA test started him on a path to prostate cancer diagnosis and surgery. The surgery made him incontinent. Humiliated by accidents, he couldn’t be far from a toilet so could no longer coach soccer or go on his daily long walk with friends. He became socially isolated and sedentary. He put on weight. And he developed diabetes.

Now his health is worse, but it’s not only his health that has been affected. Other aspects of his well-being – attachment to his friends and the ability to live the life he wants – have been undermined. His story is, sadly, not unusual, except for one thing.

The hospital where he was treated called him in to apologise for operating unnecessarily and harming him. Both he and his clinicians concede he was over-diagnosed (the disease would not have produced symptoms or shortened his life) and over-treated (he received treatment he didn’t need.)

The popularity of screening

Over-diagnosis and over-treatment happen for many reasons – commercial interests, technological developments, medico-legal threats and deliberate profiteering. But as consumers, we also contribute.

In one British study, men described turning up to their GP determined to have a PSA test. In an Australian one, women worried that expert disagreement on PSA testing might discourage men from being screened. Most respondents to a US survey were enthusiastic about cancer screening, with 73% saying they’d rather have a full-body CT scan than $1,000 cash. Many thought it was irresponsible for healthy adults to avoid cancer screening.

We’re not just willing to go fishing for diseases. Some of us think it’s a moral obligation. And this is not surprising given two commonly accepted characteristics of contemporary Western society: we expect to be able to predict and control the future, and we tend to see health as an individual responsibility.

Benefits and harms

Moral obligation is the territory of ethics. So how should we think about the ethics of over-diagnosis in healthy people?

We need to start by weighing benefits against harms, but this is harder than it seems.

The benefits of tests and treatments are often overstated (so straight-talking interpretations like these are invaluable). Evidence is contested, uncertain and incomplete. Harms, in particular, are under-studied, and they’re not only physical.

If we are diagnosed (say, with cancer), we see ourselves differently. And a diagnosis can affect future generations. A cancer diagnosis in a parent can mean their child is declared “high risk” for developing cancer, potentially changing his or her medical care, insurance status, and self-concept for life.

Sometimes doctors or policymakers impose these harms on us, but not always. If patients demand tests or treatments, clinicians must trade-off possible harms against their duty to respect the choices and goals that matter to us. When decision-makers try to reduce harms by limiting services, they are often met with community outrage.

This passion is understandable. Unlike my friend’s dad, most over-diagnosed and over-treated people falsely believe they were saved from death by timely intervention. So it makes sense that they would altruistically defend others’ right to be saved.

Reimagining society

We’re all in this mess together: trying to be good citizens, control the future, and wrestle with the uncertainty of science. It’s a difficult challenge, but it’s not impossible.

In 2007 in New Zealand, researchers gathered 11 women aged 40 to 49 together to consider the evidence on mammographic breast cancer screening in women their age. At the beginning, all 11 women supported screening. After two days of briefing and deliberation, ten out of 11 were against. We can’t replicate this process for everyone and every test, but it shows the power of good information and reasoned debate.

So what should we do? It depends on the disease and the treatment, and so on the evidence, however uncertain. But it also depends on our vision of a good society.

Over-diagnosis and over-treatment have arisen mostly from a high-tech chase after ever-more-finely-dissected risks in healthy individuals. There’s increasing concern that this chase is doing little for our health, and that the good it does is at the expense of people like my friend’s dad.

It’s not just these active harms we should worry about. We should also be concerned about the opportunity costs. We’ve known for decades that the best way to improve health is to improve the basics, like the food supply, the built environment, and the fairness of our social and economic systems. Changes like these are good for everyone’s health, and especially for the health of the least well off.

And such changes can only be achieved through collective effort. Perhaps the solution to over-diagnosis and over-treatment includes changing the way we think about ourselves: less as individual disease time-bombs, and more as members of a community, with a shared responsibility to work together to make it easier for everyone to be healthy.

More on Overdiagnosis.


17 September 2012, 6.25am AEST

Over-diagnosis: the view from inside primary care


OVER-DIAGNOSIS EPIDEMIC – We kick off the second week of this series with Jenny Doust looking at some drivers of over-diagnosis in general practice. It’s easy to dismiss general practice as being about minor illnesses requiring little clinical acumen. We see patients with the common symptoms of life…

Of all the teenagers with flu-like symptoms, GPs need to find the one with a lymphoma in his chest. Joey Yee

OVER-DIAGNOSIS EPIDEMIC – We kick off the second week of this series with Jenny Doust looking at some drivers of over-diagnosis in general practice.

It’s easy to dismiss general practice as being about minor illnesses requiring little clinical acumen. We see patients with the common symptoms of life – coughs, fevers, backache and abdominal pain. Most of these are transitory and, for the large proportion, medical intervention makes little difference.

The diagnostic skills of a general practitioner, however, need to be as acute as those of House MD. Among all the children we general practitioners see with diarrhoea, we need to be able to pick the one with Crohn’s disease requiring urgent surgery. Among all the women who complain of feeling tired, we need to isolate the one who has life-threatening Addison’s disease. And among all the teenagers with flu-like symptoms, we need to find the one with a lymphoma in his chest.

These are all patients I have seen during my time as a general practitioner and they remind me constantly to take every person who walks through my door seriously.

Missing diagnosis

The most common reason general practitioners are sued is because of missed diagnoses. Missed diagnoses also invoke a strong sense of professional failure. So how can general practitioners manage in this sea of uncertainty?

One way is to perform more tests. This is also popular with patients, who perceive that tests ensure nothing serious is missed. What is not well understood by patients (and sometimes also by clinicians) is the potential harm from testing.

The most obvious harm is the cost and resources required; we would quickly overwhelm the health system if we performed an MRI on every patient with back pain. A strong system of primary care results in a health-care system that’s both more efficient and less costly because primary-care physicians are skilled at filtering those with severe disease needing further tests, from those with self-limiting illnesses.

But even in Australia, with its highly trained general practice workforce, this skill is often under-appreciated.

Harms of testing

Less well understood are the harms due to the inherent inaccuracy of testing. By the laws of statistics, when the likelihood of a disease is very low, most positive test results will be false positives. We see this most clearly in screening programs, where most abnormal screening results will not have the disease on follow-up testing. This causes only minor harm if there is a follow-up test. But it is of much greater consequence if tests are assumed to be accurate and too much faith is put in the results.

The greatest harm from the increased use of testing, however, is not costs, resources or false positives. Rather, it’s the problem of over-diagnosis.

Clinicians and patients both believe that finding a disease earlier in its process means it will be more successfully treated. But there’s increasing evidence that finding disease early or at a milder stage has paradoxical harmful effects, even reducing survival and quality of life.

Wider availability of more sophisticated tests results in “incidentalomas”, incidental findings that would not have otherwise been diagnosed. The detection of thyroid cancers, for instance, has more than doubled in the past 30 years. But most of these diagnoses are incidental findings from imaging.

If the earlier detection of these cancers improved prognosis, you would expect to see a decline in the mortality rate from thyroid cancer. But the mortality rate has sadly been constant in this time.

Looser boundaries

Even more problematic is the widening of the definition of diseases and the lowering of disease thresholds. Examples of expanding definitions include chronic kidney disease, diabetes, and even the diagnosis of cancers, such as breast and bladder cancer.

We assume patients who are now included in the wider definition benefit from treatment as much as those using the old definition. In fact, we are likely to believe that they will benefit more as we have caught the disease early. But all medical treatments cause harm. And when patients with milder disease are treated, it becomes more likely that the potential harm of medical treatment will outweigh the benefits.

Wider disease definitions become self-reinforcing – we find more and so we test more. And because we have now included milder patients in our disease group, we are misled by the perceived improvement in patient survival and the reduction in disease complications in our new patient group.

What now?

Right now, we are in the midst of a perfect storm – a population that is increasingly anxious about health, doctors who don’t want to miss a diagnosis, a pharmaceutical industry that profits from widening the definitions of disease and a health system that rewards over-testing and fails to acknowledge the harms that can result from it.

We have set up a group to look for solutions to this problem, including a conference in 2013, but the answers are far from clear. Given the pervasive nature of over-diagnosis, solutions will need to involve all layers of the health-care system, including policy makers and key clinical opinion leaders.

As a general practice physician, I am hoping we will be able to spend less time labelling patients with an ever increasing number of “diseases” and to spend more time working with them on solving their health problems.

Prostate cancer Overdiagnosis.

PSA screening and prostate cancer over-diagnosis

OVER-DIAGNOSIS EPIDEMIC – We finish our first week of this series with Robert Burton, Christopher Stevenson and Mark Frydenberg examining prostate cancer screening. Scientific oncology started with the creation of the modern microscope, which provided the basis for the modern pathologic study of cancer…

To prevent one death from prostate cancer, 1,055 men would need to be screened and 37 cancers detected. Isaac Leedom

OVER-DIAGNOSIS EPIDEMIC – We finish our first week of this series with Robert Burton, Christopher Stevenson and Mark Frydenberg examining prostate cancer screening.

Scientific oncology started with the creation of the modern microscope, which provided the basis for the modern pathologic study of cancer in the late 19th century, and established the “fatal cancer” myth. As [one researcher] arguing ( against breast cancer screening put it, “since then, without pause for thought, the microscopic identification of cancer according to the classic criteria has been associated with the assumed prognosis of a fatal disease if left untreated.”

Earlier this week, an article in this series looked at the adverse effects of breast cancer screening. Today, we will examine the role of screening in the over-diagnosis of prostate cancer.

The fatal cancer myth began to unravel a century later. A 1993 study for instance, noted that prostate cancer was unique because “the frequency of histologically (pathologically) confirmed invasive cancer at autopsy greatly exceeds the prevalence of clinically significant carcinoma during life.”

The authors then affirmed that in no other malignancy was there such a vast reservoir of undetected cases that may never be clinically significant or cause death. They also noted that up to 40% of all men might be treated for prostate cancer but only 8% would ever have a cancer large enough to be diagnosed and only 3% would die of it.

Over-diagnosis of cancer is the detection of asymptomatic cancers that will not become clinically significant and cause disease or death in the patient’s lifetime. How many men have prostate cancer that might never come to light without screening and are therefore at risk of over-diagnosis?

High prevalence

A 2010 review of a 1996 study found that microscopic asymptomatic prostate cancers had been detected in 525 men of various ages killed in motor vehicle accidents in the United States (U.S). The findings indicated that this type of cancer could affect approximately a third of American men aged 30 to 39 years, increasing to about 70% at age 70 to 79 years.

Looking at these figures, together with similar autopsy studies, the authors of the review concluded prostate cancer was likely detectable in between 30 to 70% of men over 60 years old.

And a 2009 Australian study of prostate tissue, sampled from 133 cadavers referred for coronial autopsy, found invasive prostate cancer in about a quarter of the 70 men aged 50 or more years.

It seems over-diagnosis of prostate cancer was already inevitable by the time the Prostate Specific Antigen (PSA) blood test was introduced for prostate cancer screening in Australia in the late 1980s, because it could detect cancers that had previously gone undiagnosed.

Since PSA testing began in the late 1980s, over 75,000 Australian men may have been turned into prostate cancer patients, possibly for only a small benefit. Alex E Proimos

Winds of change

In July 2012, the U.S. Preventive Services Task Force (USPSTF) found that “The mortality benefits of PSA-based prostate cancer screening through 11 years are, at best, small and potentially none, and the harms are moderate to substantial”. The task force recommended against PSA-based screening for prostate cancer, stating that the recommendation applied to men in the general U.S. population, regardless of age.

The recommendation was based on an analysis of the evidence from trials of PSA screening in the U.S. and Europe, but mainly on the 2009 report of the European randomised controlled trial (RCT), where 182,000 men aged 50 to 74 years from seven European countries were randomised to either PSA testing every two to seven years or to usual care.

This report was updated in 2012 with an average follow-up of 11 years. It found a statistically significant reduction (21%) in prostate cancer mortality in the population of men invited to screen and a 29% reduction in those who were actually screened.

But this reduction in mortality came at a cost. The authors reported that to prevent one death from prostate cancer at 11 years follow-up, 1,055 men would need to be invited for screening and 37 cancers would need to be detected. The USPSTF also noted that there was convincing evidence PSA-based screening led to substantial over-diagnosis of prostate tumours.

Unknown quantity

The amount of over-diagnosis of prostate cancer is an important concern because men with cancers that would remain asymptomatic for the remainder of their lives cannot benefit from screening or treatment.

Based on our analysis of trends in prostate cancer incidence (new cases per year) since PSA testing began in the late 1980s, over 75,000 Australian men who might never have known they had prostate cancer may have been turned into prostate cancer patients, possibly for only a small benefit.

At the same time, the men were exposed to the potential harms (incontinence, impotence) of unnecessary treatment. These harms can be avoided if the prostate biopsy shows that they have low-risk disease and are then managed by active surveillance, rather than immediate treatment of their cancer.

Deaths from prostate cancer have fallen by approximately 13,000 during that same time. Some men can be saved by early detection and treatment but others clearly do not benefit.

Performing PSA tests on everyone leads to substantial over-diagnosis. But not performing PSA tests at all would inevitably lead to under-diagnosis of some men who may have been cured by early detection and treatment. Before consenting to undergo PSA screening, men should understand that while there are possible, if modest, benefits to getting tested, they may be exposed to substantial harms from over-diagnosis and over-treatment.