Public Health Center

As the world population in Western countries ages, environmental conditions and social infrastructure continue to deteriorate and demand for health care services increases, it is a fact that public health and environmental science will be growth industries. Earning a public health degree or environmental science degree from an Australian college can go a long way toward helping you to get a top-paying job in one of these expanding fields.

There are good reasons to study such subjects at a college in Australia. This country faces a number of interesting and difficult environmental issues as well as public health problems (Australians suffer from some of the world's highest rates of mesothelioma - read on); those who pursue degree programs in this country have an excellent opportunity to see these problems up close, as well as how they are being addressed.

Another reason to study in Australia; college overseas gives one a much broader perspective - and this is something that prospective employers appreciate.

If you already have a public health degree, attending college in Australia is a good way to complete continuing education requirements and advance in your career. At an Australian college, you will have to opportunity to see how that society addresses many of the issues that faces the U.S. today and will be able to study what works, what doesn't, and why.

Prospective oncologists will have some unique opportunities in Australia. Colleges of medicine in this country are able to study what is a very rare disease. Asbestos cancer has been much more common in Australia than other parts of the world, as asbestos mining was a major industry for decades. While this is a tragedy, it provides those specializing in oncology to study this unusual form of the disease in a range of patients. This is only one reason why completing a public health degree in Australia is an excellent idea.

Environmental science is another part of public health policy, and here too, Australian colleges offer some unique opportunities. Not only is Australia unique in many ways, the country is facing some major challenges, having been in a state of drought for decades. An environmental science degree through a college in Australia affords the opportunity to study how Australians are managing increasingly scare water resources - yet another issue that is faced by many western states.

Hyperhidrosis, also known as polyhidrosis or sudorrhea means excessive sweating; sweating too much. Hidrosis means sweating, while hyper means too much, or excessively. The excessive sweating may be either localized in specific parts of the body, or generalized (everywhere). Most cases of excessive sweating tend to start during a person's teenage years - their adolescence.

The most active regions of perspiration include the hands, feet, armpits and the groin area because of a relatively high concentration of sweat glands in those areas.

• Focal hyperhidrosis - when the excessive sweating is localized; affects (a) specific area(s). For example palmoplantar hyperhidrosis or acrohyperhidrosis is symptomatic sweating of primarily the hands or feet.
  
  
• Generalized hyperhidrosis - when the excessive sweating affects the entire body.

Hyperhidrosis may be congenital or an acquired trait. Congenital means you are born with it, while an acquired trait means you are not; the condition is acquired later in life after birth.

Hyperhidrosis may be categorized as being the result of an underlying health condition, or with no apparent cause:

• Primary idiopathic hyperhidrosis - there is no apparent cause. Idiopathic means "of unknown cause". In the majority of cases the hyperhidrosis is localized.
  
  
• Secondary hyperhidrosis - the person sweats too much because of an underlying health condition, such as obesity, gout, menopause, a tumor, mercury poisoning, diabetes mellitus, or hyperthyroidism (overactive thyroid gland). It can also be caused by some medications. Generalized hyperhidrosis is more common among patients with secondary hyperhidrosis.

According to the National Health Service (NHS), UK, approximately 3% of England's population (1.53 million people) is affected by hyperhidrosis. According to the International Hyperhidrosis Society 3% of the world's population is affected.

For some people hyperhidrosis symptoms are so severe that it becomes embarrassing, causing discomfort and anxiety. The International Hyperhidrosis Society describes the consequences of hyperhidrosis as sometimes even disabling. The patient's career choices, free time activities, personal relationships, self-image and emotional well-being may be affected.

Fortunately, there are several options which can treat symptoms effectively. In severe cases surgery may effectively stop the excessive sweating. The National Health Service (NHS), UK, mentions that the biggest challenge in treating hyperhidrosis is the significant number of people who do not seek medical advice, either due to embarrassment or possibly because they do not know that effective treatment exists.

According to Medilexicon's medical dictionary Hyperhidrosis is "Excessive or profuse sweating."

What are the signs and symptoms of hyperhidrosis?

A symptom is something the patient senses and describes, while a sign is something other people, such as the doctor notice. For example, drowsiness may be a symptom while dilated pupils may be a sign.

Sweating is part of our body's cooling mechanism - it regulates our body temperature. When it is too hot, we sweat. The sweat on our skin evaporates, taking heat with it. Hyperhidrosis is when we sweat more than we have to in order to regulate our body temperature. It is defined as sweating that disrupts normal activities. Episodes of excessive sweating occur at least once a week for no clear reason.

There is no normal sweat measurement which can associate body weight with heat triggers, such as environmental temperature, exercise, etc. People know when they sweat excessively and it starts to have an effect on their social life or daily activities.

Signs and symptoms of hyperhidrosis may include:

• Clammy or wet palms of the hands
• Clammy or wet soles of the feet
• Frequent sweating
• Noticeable sweating that soaks through clothing

People with hyperhidrosis:

• In severe cases there maybe irritating and even painful skin problems, such as fungal or bacterial infections.
• May be constantly worried about having stained clothing
• May be reluctant to make any physical contact
• May be self-conscious
• May become socially withdrawn. There may be fear about what others might think, so the sufferer makes excuses to stay at home. Sometimes this may lead to depression.
• May select employment where physical contact or human interaction is not a job requirement.
• May spend an enormous amount of time each day dealing with sweat, such as changing clothes, wiping, placing napkins or pads under the arms, washing, wearing bulky, or dark clothes.
• May worry more than other people about body odor

The areas of the body most commonly affected are:

• Armpits
• Face
• Feet
• Palms of the hands

Experts are not certain why, but excessive sweating during sleep is not common for people with primary hyperhidrosis (the type not linked to any underlying medical condition).

What are the causes of hyperhidrosis?

Causes of primary hyperhidrosis (type not caused by an underlying condition or medication) - people used to think that primary hyperhidrosis was linked to the patient's mental and emotional state; that the condition was psychological and only affected stressed, anxious or nervous individuals.

However, recent research has demonstrated that individuals with primary hyperhidrosis are no more and no less prone to feelings of anxiety, nervousness or emotional stress than the rest of the population when exposed to the same triggers. In fact, it is the other way round - we now know that the emotional and mental feelings experienced by many patients with hyperhidrosis are due to the consequences of excessive sweating. The emotional and mental problems do not cause the excess sweating; the excessive sweating causes the emotional and mental problems.

Studies have also shown that certain genes play a role in hyperhidrosis, making it look more likely that it could well be an inherited condition. The majority of patients with primary hyperhidrosis have a sibling or parent with the condition. It is believed that a problem with the sympathetic nervous system is linked to the development of primary hyperhidrosis. The sympathetic nervous system, and the parasympathetic nervous system perform our involuntary functions - the sympathetic nervous system is involved in accelerating the heart rate, urine output, the movement of food through the digestive system, restricting blood vessels, raising blood pressure and the production of sweat.

When the sympathetic nervous system senses overheating in the body, it sends signals through ganglia (nerve pathways) to sweat glands to produce sweat, causing body temperature to drop. Experts believe the ganglia becomes over-stimulated in primary hyperhidrosis and over-produces sweat.

Causes of secondary hyperhidrosis (the type linked to an underlying condition or some medication):

• A spinal cord injury
• Alcohol abuse
• Anxiety
• Diabetes
• Gout
• Heart disease
• Hyperthyroidism - an overactive thyroid gland
• Obesity
• Parkinson's disease
• Pregnancy
• Respiratory failure
• Shingles
• Some cancers, such as Hodgkin's disease
• Some infections - HIV, malaria, TB (tuberculosis)
• Some medications, including some antidepressants, anticholinesterases (for Alzheimer's disease treatment), pilocarpine (for glaucoma treatment), propranolol (for the treatment of high blood pressure).
• Substance abuse

There are two types of sweat glands in human skin:

• Eccrine glands - found in almost all regions of skin. They produce (odorless) sweat that reaches the surface of the skin through coiled ducts (tubes). As sweat evaporates from the skin the body cools. Most sweat is produced by the eccrine glands.
  
  
• Apocrine glands - these develop in areas of the body where there is a lot of hair, as well as the breasts. The apocrine glands in the breast secrete fat droplets into breast milk. The ones found in the ear help form earwax. Those found in the skin and eyelids are sweat glands. Most of the apocrine glands in the skin are found in the groin, the area around the nipples of the breast and in the armpits - they are scent glands and their secretions generally have an odor (smell).

Our bodies have two to four million sweat glands, most of which are eccrine glands.

Diagnosing hyperhidrosis

A general practitioner (GP, primary care physician) may try to rule out any underlying conditions, such as an overactive thyroid (hyperthyroidism) or low blood sugar (hypoglycemia) by ordering blood and urine tests. Patients will be asked about the patterns of their sweating - which parts of the body are affected, how often sweating episodes occur, whether sweating occurs during sleep (rare in primary hyperhidrosis).

The patient may be asked a series of questions, or have to fill in a questionnaire about the impact of excessive sweating. The questions may be similar to the ones below (source: International Hyperhidrosis Society):

• Do you carry stuff around to deal with episodes of excessive sweating (hyperhidrosis), such as napkins, antiperspirants, towels, pads, etc.?
• Do you find you have to buy new clothes and shoes more often than others do?
• Does hyperhidrosis affect your behavior or mental state when you are in public?
• Does the thought of having to touch other people in a social situation make you sweat?
• Has hyperhidrosis had any effect on your employment?
• Has hyperhidrosis ever made you alter your social plans?
• Have you ever lost a friend due to hyperhidrosis?
• Does your hyperhidrosis mean you have to spend a lot of your day having to deal with it? If so, how much?
• How often do you change your clothing?
• How often do you wash and/or have a shower/bath?
• How often do you think about excessive sweating?
• When you are in a social situation when you have to touch other people, do you sweat?
• Would you say you have experienced more skin infections or irritations than other people?

In most cases hyperhidrosis which affects all or most of the body (generalized hyperhidrosis) has an underlying condition, while primary hyperhidrosis tends to affect specific parts of the body (focal hyperhidrosis).

Thermoregulatory sweat test - a powder which is sensitive to moisture is applied to the skin. When excessive sweating occurs at room temperature the powder changes to dark purple (from yellowish-green). This is documented with a digital photo. The patient is then exposed to high heat and humidity in a sweat cabinet, which triggers sweating throughout the whole body.

When exposed to heat people who do not have hyperhidrosis tend not to sweat excessively in the palms of their hands, as opposed to patients with hyperhidrosis who do. This test helps the doctor determine the severity of the condition, as well as making a more accurate diagnosis.

The doctor will probably diagnose primary hyperhidrosis if:

• Episodes of excessive sweating occur at least once weekly
• Excessive sweating does not occur during sleep
• Excessive sweating occurs in both affected parts of the body, e.g. both armpits, both feet, or both hands
• The patient suffers from focal hyperhidrosis (only limited parts of the body are affected)
• There appears to be no underlying condition/illness that may be causing it

What are the treatment options for hyperhidrosis?

Treatment for primary hyperhidrosis (no underlying condition is found) - experts say that some alterations in daily activity and lifestyle may help improve symptoms. These measures will not cure the condition, though:

• Antiperspirants - remember that deodorants do not stop sweating, while antiperspirants sprays do. Use antiperspirants often. If an OTC (over-the-counter, no prescription required) antiperspirant is not effective enough, ask your doctor for a prescription antiperspirant, especially one with aluminum chloride, which plugs up the sweat glands. It should be applied on dry skin before going to bed and rinsed off after waking up.
  
  
• Armpit shields - these are pads worn in the armpit to protect a garment from perspiration.
  
  
• Clothing - beware of certain synthetic fibers, such as nylon, which may worsen symptoms. Wear loose clothing.
  
  
• Shoes - those made of synthetic materials are more likely to worsen symptoms. Use only natural material, such as leather.
  
  
• Socks - some socks are better at absorbing moisture, such as thick, soft ones made of natural fibers. Some sports socks are specifically designed to absorb sweat. Change your socks regularly, twice or three times a day if you have to. Avoid synthetic fibers.
  
  
• Triggers - certain foods and drinks (alcohol) may trigger excessive sweating. If you are able to identify them, avoid them.

If the measures mentioned above are not effective (enough) the GP may refer the patient to a specialist skin doctor (dermatologist), who may recommend:

Iontophoresis - the hands and feet are submerged in a bowel of water. A painless electric current is passed through the water. Iontophoresis can also be used to treat the armpits, where a wet pad is applied; however, the treatment is less effective than for the feet and hands. Most patients need two to four 20 to 30 minute treatments. Some time later they may have more sessions at four-week intervals.

Treatment is usually given either in a hospital or dermatology clinic. There are some kits which can be used at home. Experts say that iontophoresis can be over 80% effective for the treatment of feet and hands.

Botulinum toxin (Botox injections) - research has shown that Botox injections are effective in blocking the nerves that trigger the sweat glands. Botox is the same product that is used to smooth facial wrinkles (it paralyzes specific muscles). Patients with hyperhidrosis may need several injections for effective results. The National Health Service (NHS), UK, says that about 12 injections are usually needed. The effects generally last from 2 to 8 months.

Anticholinergic drugs - these medications inhibit the transmission of parasympathetic nerve impulses. They block the actions of a chemical messenger (acetylcholine) which helps stimulate the sweat glands. Patients generally notice an improvement in symptoms within about two weeks. If side effects do occur they tend to be mild, and may include:

• Blurred vision
• Confusion
• Constipation
• Difficulty in emptying the bladder completely (urinary retention)
• Dizziness
• Dry mouth
• Loss of taste

Patients who develop diarrhea, a rash, hives, or have difficulty swallowing or breathing should see their doctor immediately.

ETS (Endoscopic thoracic sympathectomy) - this surgical intervention is only recommended in severe cases which have not responded to other treatments. The nerves that carry messages from the sympathetic nerves to the sweat glands are cut. Two to three small incisions are made on the side of the chest so that a video camera and small surgical instruments can be inserted. An endoscope (long thin tube with a camera at the end) is inserted into the chest cavity, giving the surgeon a clear view of the patient's chest cavity. ETS may be used to treat hyperhidrosis of the face, hands or armpits. ETS is not recommended for treating hyperhidrosis of the feet because of the risk of permanent sexual dysfunction.

The National Health Service (NHS), UK, says that ETS is moderately successful in treating hyperhidrosis. However there is a risk of complications:

• Compensatory hyperhidrosis - sweating may start occurring in another part of the body, such as the upper thighs or lower back. Even so, most patients find this complication easier to live with than their original hyperhidrosis.
  
  
• Gustatory sweating - there may be sweating on the neck and face after eating.
  
  
• Rhinitis - the inside of the nose becomes inflamed (swells), causing cold-like symptoms, such as itchiness, blocked nose, runny nose and sneezing.
  
  
• Respiratory problem - air can become trapped in the pneumothorax, causing chest pain and some breathing problems. Treatment is not usually required and the condition gets better on its own.
  
  
• Horner's syndrome - paralysis of certain nerves which causes the eyelids to droop (very rare).
  
  
• Phrenic nerve damage - this nerve is involved in the regulation of our breathing (very rare). If it is damaged the patient may experience breathlessness. The damage can be treated during surgery.

Treatment for secondary hyperhidrosis (an underlying condition is causing it) - the underlying cause needs to be treated and controlled.

What are the possible complications of hyperhidrosis?

• Nail infections - patients with hyperhidrosis are more vulnerable to fungal nail infections, especially toenail infections. The warm, moist environment offered by, for example, sweaty shoes are ideal for fungi to thrive.
  
  
• Warts - skin growths caused by the HPV (human papillomavirus).
  
  
• Bacterial infections - patients with hyperhidrosis are more prone to developing skin infections, especially around hair follicles and between their toes.
  
  
• Heat rash (prickly heat, miliaria) - an itchy, red skin rash that often causes a stinging or prickling sensation. Heat rash develops when sweat ducts become blocked and perspiration is trapped under the skin. This causes irritation and results in the rash.
  
  
• Psychological impact - excessive sweating can affect the patient's self-confidence, job, and relationships. It might eventually control and undermine their ability to enjoy life. Some individuals may become anxious, emotionally stressed, socially withdrawn, and even depressed. On average, a person with hyperhidrosis seeks medical help after living with the condition for 9 years. It is important to spread the word that the symptoms of excessive sweating can be effectively treated.

Having high blood pressure occasionally may pose a higher risk of having a stroke than having consistently high readings: a series of UK-led research papers published this week in leading journals suggests doctors should not ignore one-off high blood pressure readings and consider blood pressure variability and maximum blood pressure as risk factors for stroke rather than just average blood pressure.

You can read about the research in a series of papers published online this week in The Lancet and The Lancet Neurology. The lead author is Dr Peter Rothwell, a professor of neurology at the University of Oxford, UK.

Rothwell told the media that the main message coming out of the research is that doctors have to start viewing blood pressure differently.

Current guidelines say that the priority is to lower blood pressure to reduce the risk of having a stroke, but the work that Rothwell and colleagues have done suggests that doctors should also take into account blood pressure variability and prescribe the drugs that result in the most steady blood pressure.

In the study published in The Lancet, Rothwell and colleagues looked at high blood pressure and visit-to-visit blood pressure variability in four groups of 2,000 people (UK-TIA trial and three validation cohorts), each of whom had experienced transient ischemic attacks (TIAs), often dubbed "mini-strokes", considered warning signs of stroke risk.

They found that in each TIA cohort, the visit-to-visit variability in systolic blood pressure (SBP, the higher of the two blood pressure readings that a doctor takes, eg the 120 in a 120/80 reading) and maximum blood pressure were both strong predictors of subsequent stroke.

Those participants with the greatest variation in SBP over seven GP visits were six times more likely to have a major stroke and those with the highest blood pressure readings were 15 times more likely to have a stroke.

The authors concluded that:

"Visit-to-visit variability in SBP and maximum SBP are strong predictors of stroke, independent of mean SBP."

In a second Lancet study, Rothwell and colleagues conducted a meta-analysis (where you analysed data pooled from several studies of similar design and measurement criteria) of 389 controlled trials and found that blood pressure variability was a probable explanation for why some types of drugs were more effective than others at preventing strokes.

In this second study, they concluded that:

"Drug-class effects on interindividual variation in blood pressure can account for differences in effects of antihypertensive drugs on risk of stroke independently of effects on mean SBP."

And in a third study, published in The Lancet Neurology, Rothwell and colleagues compared the effects of β blockers and calcium-channel blockers on blood pressure variability and how this might impact risk of stroke.

Previous studies have found that on the basis of mean blood pressure alone, calcium-channel blockers reduce the risk of stroke more than expected and β blockers less than expected.

For this study they examined the results of two trials: the Anglo-Scandinavian Cardiac Outcomes Trial Blood Pressure Lowering Arm (ASCOT- BPLA) trial involving 19,257 patients with hypertension and other vascular risk factors, and a Medical Research Council (MRC) trial involving 4,396 hypertensive patients.

They found that calcium-channel blockers and β blockers have opposite effects on blood pressure variability: with the former gradually reducing variability over time, and the latter gradually increasing it.

The researchers concluded that the opposite effects of "calcium-channel blockers and β blockers on variability of blood pressure account for the disparity in observed effects on risk of stroke and expected effects based on mean blood pressure"; they recommended that:

"To prevent stroke most effectively, blood-pressure-lowering drugs should reduce mean blood pressure without increasing variability; ideally they should reduce both."

In a review article in The Lancet, Rothwell discusses what he describes as the "shortcomings of the usual blood pressure hypothesis" and suggests avenues for future research.

He argues that while high blood pressure is the most common treatable vascular risk factor, we don't know very much about how it causes end-organ damage and leads to vascular events, yet there is a widespread belief that "underlying usual blood pressure can alone account for all blood-pressure- related risk of vascular events", and this has influenced guidelines for diagnosis and treatment.

In the meantime, potentially valuable information is ignored, such as variability in clinic blood pressure or maximum blood pressure reached, with the result that we know little about the effects of widely used drugs on these measures, writes Rothwell.

Dr Philip B. Gorelick, a leading American expert on blood pressure and stroke, and director of the Center for Stroke Research at the University of Illinois, who also wrote a commentary in one of the journals to accompany the studies, told the media (as reported by HealthDayNews) the findings are "compelling" and may "revolutionize how we treat blood pressure in the future":

"They provide a very important foundation for change in future treatment," said Gorelick.

He said first doctors may begin to screen patients for blood pressure variability and see if it is possible to select for classes of drugs that reduce it.

"And we can certainly adopt an at-home program to detect blood pressure variability, although within-visit variability seems to be a more important factor," he added.

He said the study on the different effects on variability of calcium-channel blockers and β blockers may also affect choice of the first drugs prescribed for blood pressure control:

"We would consider calcium channel blockers and diuretics for initial use," said Gorelick.

Joe Korner, director of communications at The Stroke Association, commented to the BBC about the new findings and said that people who have what is called episodic hypertension, where their blood pressure occasionally registers a high reading, are often not treated.

Korner urged GPs to read the new research to help them decide the best treatment for patients at risk of stroke.

In the UK, clinical guidelines are regulated by the National Institute for Health and Clinical Excellence (NICE), and they are in the process of reviewing the guidelines on high blood pressure: it is understood that they will be taking these latest studies into account.

"Prognostic significance of visit-to-visit variability, maximum systolic blood pressure, and episodic hypertension."
Peter M Rothwell, Sally C Howard, Eamon Dolan, Eoin O'Brien, Joanna E Dobson, Bjorn Dahlöf, Peter S Sever, Neil R Poulter.
The Lancet, Volume 375, Issue 9718, Pages 895 - 905, 13 March 2010
DOI:10.1016/S0140-6736(10)60308-X

"Effects of antihypertensive-drug class on interindividual variation in blood pressure and risk of stroke: a systematic review and meta- analysis."
Alastair JS Webb, Urs Fischer, Ziyah Mehta, Peter M Rothwell
The Lancet, Volume 375, Issue 9718, Pages 906 - 915, 13 March 2010
DOI:10.1016/S0140-6736(10)60235-8

"Limitations of the usual blood-pressure hypothesis and importance of variability, instability, and episodic hypertension."
Peter M Rothwell
The Lancet, Volume 375, Issue 9718, Pages 938 - 948, 13 March 2010
DOI:10.1016/S0140-6736(10)60309-1

"Effects of β blockers and calcium-channel blockers on within-individual variability in blood pressure and risk of stroke."
Peter M Rothwell, Sally C Howard, Eamon Dolan, Eoin O'Brien, Joanna E Dobson, Bjorn Dahlöf, Neil R Poulter, Peter S Sever, on behalf of the ASCOT-BPLA and MRC Trial Investigators.
The Lancet Neurology, Early Online Publication, 12 March 2010
DOI:10.1016/S1474-4422(10)70066-1

Obesity and alcohol act together to increase the risk of liver disease in both men and women according to two studies published on bmj.com today. These findings have significant clinical and public health implications.

In the UK, rates of liver disease and obesity are increasing. Alcohol is a major cause of liver cirrhosis. In addition, recent evidence indicates that excess body weight may also play a role.

Researchers from the University of Oxford examined in the first study the link between body mass index (BMI) and liver cirrhosis. A total of 1.2 million middle-aged UK women took part in the Million Women Study.

Each participant was monitored for an average of 6.2 years. Risks were modified according to age, alcohol consumption, smoking, socioeconomic status and physical activity.

Women who were overweight or obese had an increased relative risk of liver cirrhosis compared to women of a healthy weight. This relative risk did not differ considerably by alcohol consumption, but the absolute risk did.

For instance, among women who reported drinking an average of about a third to half a drink a day, 0.8 in 1,000 will be admitted to hospital with, or will die from, liver cirrhosis over five years if they are of healthy weight. This compares with 1 in 1,000 women who are obese.

However, among women who reported drinking an average of two and a half drinks a day, 2.7 in 1,000 will be admitted to hospital with or will die from liver cirrhosis over five years if they are of healthy weight. This compares with 5 in 1,000 women who are obese.

Researchers from the Universities of Glasgow and Bristol investigated in the second study the joint effects of BMI and alcohol consumption on liver disease in more than 9,000 men in Scotland. Participants were monitored for an average of 29 years.

Both factors were related to liver disease. Significantly, the combination of high BMI and alcohol consumption was greater than the additive effect of the two separate factors.

For instance, obese men who reported drinking 15 or more units per week had the greatest risk of liver disease: almost 19 times higher than underweight or normal weight non-drinkers. The researchers observe that lower, BMI specific "safe" limits of alcohol consumption may need to be defined for people who are overweight. They explain that in addition preventive efforts are required to limit the affordability and availability of alcohol and to increase physical activity.

From a public health standpoint, both studies conclude that strategies to reduce both excessive alcohol consumption and excessive body weight should result in a decline in the prevalence of liver disease.

In an associated editorial, Professor Christopher Byrne at the University of Southampton and Dr Sarah Wild from the University of Edinburgh comment that upcoming research must center on improved diagnosis and treatment of non-alcoholic fatty liver disease. This is a build-up of fat in the liver caused by obesity, high alcohol intake and diabetes and which can lead to cirrhosis.

They write that, for now, the old proverb of "prevention is better than cure" remains relevant. "Reducing alcohol consumption and obesity are, at present, our only weapons against non-viral liver disease. The progression of non-alcoholic fatty liver disease to end stage liver disease can now be added to the list of the undesirable consequences of modern lifestyles."

"Body mass index and risk of liver cirrhosis in middle aged women in UK: prospective study"
Bette Liu, senior research fellow, Angela Balkwill, statistical programmer, Gillian Reeves, statistical epidemiologist, Valerie Beral, professor of epidemiology on behalf of the Million Women Study Collaborators
BMJ 2010; 340:c912
doi:10.1136/bmj.c912

"Effect of body mass index and alcohol consumption on liver disease: analysis of data from two prospective cohort studies"
Carole L Hart, research fellow, David S Morrison, clinical senior lecturer in cancer epidemiology, G David Batty, Wellcome trust fellow, Richard J Mitchell, professor of health and environment, George Davey Smith, professor of clinical epidemiology
BMJ 2010; 340:c1240
doi:10.1136/bmj.c1240

"Body fat and increased risk of cirrhosis"
Christopher D Byrne, professor of endocrinology and metabolism, S H Wild, reader in epidemiology and public health
BMJ 2010;340:c774
bmj.com