Business Times - 30 May 2009
When weight loss spells trouble
Weight loss not only indicates the presence of underlying disease, it also affects treatment. By Cheah Ui-Hoon
THERE'S good weight loss (the kind that indicates a successful diet or exercise regime) and bad weight loss (the kind that makes a person shed kilos and look gaunt, even though they didn't go on a diet). The kind of rapid weight loss that leaves one looking emaciated is the type that has older folks muttering: 'It's not healthy. Something could be wrong.'
Now, doctors realise that unintentional weight loss isn't just an indicator of disease - usually, cancer - but that it has to be tackled or otherwise it could affect treatment. 'Much has been said about weight gain given that we're facing an epidemic of obesity, but little is said about weight loss,' says Dr Maurizio Muscaritoli, head of the Clinical Nutrition Management Unit at Rome's Sapienza University Hospital.
Unintentional weight loss is usually disease-related, he points out, and the reasons can be numerous. Someone with an inflammatory bowel disease, for example, will experience mal-absorption of nutrients.'Unintentional weight loss also indicates the presence of underlying disease or inflammation. Chronic disease is usually related to low to mild degree inflammation causing metabolic alterations in the body,' he says.
Inflammation can cause increased energy expenditure, abnormal utilisation of glucose (because of insulin resistance) or increased protein catabolism (degradation) in the muscle. Inflammation can also cause anorexia, a reduced desire to eat, which is common during chronic diseases such as cancer. In fact, this type of secondary anorexia makes up 80 to 90 per cent of anorexia cases, as opposed to Anorexia Nervosa, which is an eating disorder. 'But not a lot of people are aware of the risks of unintentional weight loss. The problem on the whole is underestimated,' says Dr Muscaritoli.
The hallmark of unintentional weight loss is that victims tend to lose lean body mass. Even during Hippocrates' time, the Greek doctors had coined a word, cachexia, for 'bad condition' describing the muscles melting down,' he says. Cachexia is particularly relevant in cancer patients - it is known as cancer cachexia - and represents the end-stage of disease-related malnutrition. 'Up to 20 per cent of cancer patients die because of consequences of cachexia, so in cancer patients cachexia has a negative impact on survival and quality of life,' says the doctor.
Weight loss and cancer
'If cancer patients lose more than 5 per cent of pre-illness body weight before treatment, their risk of mortality is higher,' says Dr Muscaritoli, adding that pre-treatment weight loss is an independent indicator of survival. Cancer patients with weight loss are also less tolerant of treatment like radiotherapy or chemotherapy. 'So quite often, the intensity of the treatments has to be reduced, which means that patients have less chances to be properly treated.'
The prevailing problem is that both oncologist and patient have focused their attention on the tumour, and frequently forget about the person with the cancer. 'The modern approach to cancer patients must take into account not only the tumour but the person and their quality of life which is strongly influenced by nutritional status,' says Dr Muscaritoli.
So when should you be alerted to unintentional weight loss? If you lose 10 per cent in six months or 5 per cent in three, says the specialist, who also cautions against extreme diets. This rate of unintentional weight loss is clinically significant, he adds. 'Patients should find out the reason,' he says. 'There's routine analysis for this.' There are only a few tumours for which therapy will cause weight gain, he notes. 'As a general rule, every cancer patient is at risk of malnutrition and cachexia.'
Cancer patients need specific nutrition because weight loss may not be related to eating less, but also metabolic alterations. EPA (eicosapentaenoic acid) is a nutrient that's especially useful in the prevention and treatment of weight loss. Dr Muscaritoli prescribes a 2 gram dose daily. The Omega Three fatty acid has been shown in clinical trials to be able to maintain or restore body weight and lean body mass in cancer patients, provided the patient also gets adequate amount of protein and calories.
'EPA is also capable of interfering with those mechanisms which are partly responsible for cancer-related weight loss and cachexia, and has been shown to improve appetite,' the doctor points out, as Omega 3 has anti-inflammatory properties. 'We now have some clinical trials showing that the administration of oral nutrition supplements containing EPA, proteins and calories may prevent weight loss and loss of muscle in a number of different cancer patients,' he says. Amounts higher than 2 grams aren't more effective, but the minimum seems to be 2 grams, he adds.
Dr Muscaritoli was invited by Abbott Nutrition to give a talk to physicians, oncologists and nutritionists about the impact of cancer cachexia and the role of ProSureÂ®, an eicosapentanoic acid (EPA)-containing oral nutritional supplement, in the management of cancer induced weight loss.
There's also a clinical study showing that children with leukaemia or solid tumours will benefit from EPA supplementation. 'EPA should become a standard treatment for cancer patients,' the doctor advises, as the first clinical trial showing positive results dates back to 2003.
Dr Khoo Kei Siong, deputy medical director and senior consultant at Parkway Cancer Centre, says EPA is often a part of a nutritional supplement product prescribed to advanced cancer patients, who are the ones most at risk of weight loss.
'Weight loss is a big issue. We know that patients who have lost a lot of weight tend not to do as well as those with minimal weight loss,' he explains, adding however that each hospital handles it differently, with some referring patients to oncology nurses and some to dietitians.
The thing also is that cachexia is poorly treatable with drugs once the patient becomes cachetic. 'So it's preventative rather than therapeutic strategies that are key,' says Dr Muscaritoli, whose department in his hospital runs a parallel nutrition programme with its oncology unit.
We may be sensitised to rapid weight gain, but weight loss - if you did not plan for it - isn't something to rejoice over either.