Weighty problem for those with fatty livers
By Lea Wee, The Straits Times, 11 Oct 2012
It used to be that fatty liver disease occurred largely in people who drank too much alcohol.
But more and more, doctors are finding it in patients who do not drink.
These patients often suffer from metabolic syndrome, a cluster of conditions which typically includes central obesity (fat around the middle) and at least two of the following conditions - high blood pressure, high fasting blood sugar, a high level of trigylcerides and a low level of high-density lipoprotein, or "good", cholesterol.
Triglycerides are a form of fat in the blood and fat tissue, used to provide energy. Good cholesterol helps the body get rid of "bad" cholesterol, which can be deposited on artery walls, narrowing the arteries.
It was also believed that metabolic syndrome harmed only parts of the body such as the brain, heart, kidney and eyes. But now, doctors are increasingly realising that it can harm the liver as well.
The liver, the largest organ in the body, helps regulate fat metabolism.
Chronic liver disease resulting from metabolic syndrome is called non-alcoholic fatty liver disease (NAFLD).
More people here are developing metabolic syndrome because of increasingly sedentary lifestyles and unhealthy diets, doctors said.
With this rise in the number of those with metabolic syndrome, liver specialists at Changi General Hospital (CGH), National University Hospital (NUH) and Singapore General Hospital (SGH) said NAFLD has overtaken other liver diseases, such as hepatitis C and alcoholic liver disease, to become the second most common liver disease seen at their clinics.
At the NUH University Digestive Clinic, the prevalence of NAFLD has increased from about 10 per cent a decade ago to about 40 per cent of all liver cases now.
At SGH gastroenterology clinic, NAFLD makes up about one in five cases there.
CGH was unable to give figures.
Paediatricians at NUH and KK Women's and Children's Hospital (KKH) also said they have been seeing more children with fatty liver disease, though they were not able to give exact figures.
The most common liver condition is still chronic hepatitis B infection. But the number of people with this condition is expected to decline in the next few years, as the success of vaccination and other measures against hepatitis B kick in.
If the rise in obesity, with its association with metabolic syndrome, in Singapore continues, NAFLD will probably overtake hepatitis B liver infection too, said liver specialists.
The proportion of obese adults here has grown from 6.9 per cent in 2004 to 10.8 per cent in 2010, the latest National Health Survey found.
An obese person is 4.6 times more likely to have NAFLD, said Dr Lee Yin Mei, a senior consultant at the NUH department of gastroenterology and hepatology.
NOT TO BE TAKEN LIGHTLY
The rising trend of NAFLD, which was first described in 1980, is a cause for concern, as more evidence emerges that it is not benign as first thought.
The form of NAFLD that is of greatest concern is called non-alcoholic steatohepatitis (inflammation or hepatitis of the liver) or Nash. It is said to affect a small yet undetermined group of people with NAFLD.
Dr Lee said studies show that about 20 per cent of Nash patients go on to develop liver cirrhosis, which is permanent scarring and hardening of the liver, after about nine years.
Like cirrhosis caused by other liver diseases, this can lead to complications such as liver cancer or liver failure or both.
Symptoms of liver failure may include ascites (abdominal distension) and bleeding varices, when the blood pressure in the liver is so great that the backflow of blood causes the blood vessels in the oesophagus (foodpipe) or stomach to burst and the patient to vomit blood or pass blood in his stools.
This was what happened to semi-retired dental surgeon Edwin Wang, 67. He saw a doctor at SGH in 2010 after he passed black stools. He was found to have liver cirrhosis caused by Nash and complicated by stage two liver cancer.
He said: "It was a shock to me. I always thought that it's usually people who drink who would end up with liver cirrhosis. But I don't drink."
Instead, he has metabolic syndrome including obesity (he used to weigh 82kg at 1.63m tall), high blood pressure, diabetes and high cholesterol.
Doctors removed the cancerous lump in his liver and his cancer is now in remission.
The cirrhosis cannot be cured but doctors are treating him with medication to reduce the blood pressure in his liver. He also had a procedure called endoscopic ligation to tie up the varices in his oesophagus to prevent bleeding.
He has also cut back on his food intake and now weighs about 72kg.
In Singapore, liver cancer is the fourth most common cancer here. Rates have remained constant - at about 7 to 8 per cent - even though the rates of hepatitis B has been going down and that of hepatitisC has remained constant. This has led to doctors to suspect that NAFLD is behind the consistent rates.
Dr George Goh, an associate consultant at the SGH department of gastroenterology and hepatology, said NAFLD has been increasingly blamed for the rising incidence of liver cancer in countries such as the United States.
In the US, where obesity affects a third of the population, NAFLD is the most common liver condition seen by liver specialists, he said.
It is the third most common reason for a liver transplant, which is the only hope for many patients with end-stage liver cirrhosis.
Recognising this, this year's fifth Liver Cancer Awareness Month organised by the SGH and National Cancer Centre Singapore in August made NAFLD its main focus.
TRICKY DIAGNOSIS, LIMITED TREATMENT OPTIONS
While some patients with a fatty liver may complain of slight discomfort on the right side below the rib cage, due to the enlargement of the liver, most experience no symptoms until the condition becomes more advanced and complications such as liver cancer or liver failure have set in.
NAFLD is usually picked up incidentally, while the patient is being treated for other problems.
For instance, doctors at KKH Gastroenterology Service come across children with NAFLD while they are being treated for abdominal pain or other gastroenterological problems.
Most have no symptoms of liver disease, said its consultant, Dr Christina Ong.
She said: "But in the process of investigating their abdominal pain, we find they have an abnormal liver function test result or a fatty liver on an ultrasound scan of the abdomen. We also need to exclude other causes of liver disease first."
In adults, it is often picked up by family doctors through a liver function blood test as part of a regular health check, said Dr Lee. Those with abnormal results may be referred to a liver specialist for further investigations.
But using a blood test or an ultrasound scan does not tell a doctor if a patient has the more harmful Nash. A liver biopsy to test a sample of liver tissue is needed for this, but it is invasive and associated with a small risk of bleeding.
Hence, a liver biopsy is done only if the patient has an abnormal liver function test result, a fatty liver shown on an ultrasound scan and other risk factors of the metabolic syndrome, Dr Lee said.
A liver biopsy is also done when doctors are not sure of the cause of a patient's liver disease.
Medication for NAFLD and Nash is still in the process of being developed.
Right now, there is no good treatment for the condition, except to lose weight through regular exercise and eating healthily.
Doctors say it may be beneficial to avoid consuming high-fructose corn syrup, found mainly in soft drinks. Studies show taking fructose contributes to the development of NAFLD. Excess sugar can be converted to fat in the liver.
Since the diagnosis and treatment of NAFLD, and the long-term effectiveness of screening, are still not established, routine screening of the condition for the public, or even those with metabolic syndrome, is not recommended, said Dr Lee, citing the latest American guidelines on NAFLD published in the journal Gastroenterology this year.
For now, the best thing that those with metabolic syndrome can do to protect their liver is to keep their body mass index (BMI) within the healthy range, she said.
For Asians, this means a BMI of between 18.5 and 22.9. BMI is calculated by dividing a person's weight in kilograms by the square of his height in metres.
That was the experience of two patients with NAFLD, both of whom also have high blood pressure.
The liver conditions of account executive Joanne Lim, 29, and retiree Mr Ooi Kew Gee, 79, improved after they lost weight, largely by halving their intake of food, and eating less oily and deep-fried food.
Ms Lim found she had NAFLD about four years ago after she saw a family doctor for intermittent sharp pain on her right side, where her liver is located.
The 1.62m-tall woman went on a diet that resulted in her weight plunging from 85kg to 58kg in about a year.
When she returned for an ultrasound scan less than a year later, her liver was no longer fatty.
An obese person with NAFLD may not need to lose as much weight as Ms Lim but doctors say he needs to lose about 10 per cent of his body weight to see a significant improvement in his liver condition.
Mr Ooi, for instance, found he had Nash about eight years ago during a regular check-up at the gastroenterology clinic for other digestive problems.
The 1.7m-tall man, who used to weigh 92kg, started to exercise and watch his diet.
Within three months, his liver blood test result returned to normal. He now weighs 81kg.
His doctor, Dr Lee, said: "He was my most motivated patient. He shows that a person can never be too old to lose weight."
Improving liver condition using balloon
Killing the appetite by having a balloon inserted into the stomach has helped a number of obese patients lose weight.
Now it may also help obese patients with non-alcoholic fatty liver disease (NAFLD) improve their liver condition, a study by doctors at the National University Hospital (NUH) has found.
The study, published in the Gastrointestinal Endoscope journal this year, is reportedly the first in the world to look at the efficacy of the intragastric balloon in moderately obese patients who have a form of fatty liver disease called non-alcoholic steatohepatitis (Nash). Their body mass index (BMI) falls between 27.5 and 37.5.
The editorial accompanying the article described the procedure as a novel and effective method to improve the condition.
In the study, eight patients with Nash had an intragastric balloon inserted in their stomach to induce a feeling of fullness. They also embarked on regular exercise and went on a healthy diet for six months.
They showed a more significant drop in their BMI - 1.52 - than the 10 patients who had only regular exercise and a healthy diet over the same period. The BMI of the latter group dropped by 0.8.
The first group also showed significantly more reduction in their NAFLD activity score (an indication of the extent of liver damage), from 4.5 before the insertion of the balloon to 2.3 six months after the balloon was inserted. In the second group, the score dropped from 4.8 to 3.7.
The main author of the study, DrLee Yin Mei, a senior consultant at the NUH department of gastroenterology and hepatology, said the difference is due to the significant weight loss that the first group experienced.
Patients are lightly sedated and awake for the procedure, in which a balloon is inserted into the stomach via the mouth using a gastroscope, and then inflated with about 500ml of saline.
This is supposed to induce weight loss by creating a feeling of fullness, so the patient would eat less.
The patient may be discharged within a few hours, though he may have a feeling of nausea for about a week afterwards, because he is not used to the feeling of having a balloon in his stomach. The balloon has to be changed every six months to avoid any risk of leakage.
Other stomach-shrinking procedures such as gastric bypass, have also been found to be effective for people with Nash, said DrLee.
But these more drastic measures, which produce greater weight loss, are better suited for the morbidly obese, she said.
An Asian is deemed to be morbidly obese if he has a BMI of 35 or higher.
Dr Lee said the gentler intragastric balloon procedure is not meant to be a permanent weight loss solution for patients, but to give them a headstart in losing some weight so that they will be motivated to change their lifestyles.
The NUH has been offering the procedure routinely to Nash patients since 2004. It costs between $2,000 and $5,000.
A patient, 64, who wanted to be known only as Jenny, said the intragastric balloon procedure helped her to lose about 10kg.
The former administrative assistant was diagnosed with Nash in her early 50s. She also had hypertension and arthritis. Weighing about 84kg at 1.53cm, she was obese with a BMI of almost 36.
She was advised to exercise regularly but gave the excuse that she had no time. Dieting also did not work for her, she said, as she loved her food too much.
Things turned around when she agreed to join the NUH study.
After the balloon was inserted about four years ago, she felt nauseous but the feeling went away after a few days.
The best thing was, the procedure worked.
She said: "I felt less hungry and was able to eat less. I cut down on fried food and sweets and stopped taking supper."
The change in her lifestyle stayed, even though the balloon was taken out six months later, when the study was completed.
She now weighs 71kg, giving her a BMI of about 30. She hopes to lose more weight.
Meanwhile, her liver condition, as well as her hypertension and arthritis, has improved.
She said: "I felt more confident and energetic overall. Even after I retired a couple of years ago, I was able to continue working as a professional nanny."
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