Recent statistics suggest that approximately 56% of females and 29% of males are overweight or obese, which is on par with figures in the US. Of that, a high percentage is believed to suffer from hypertension or high blood pressure, dubbed the 'silent killer' because of its notable absence of early symptoms.
In an effort to prevent obese patients from becoming hypertensive, doctors in South Africa have begun using genetic technology to test for variation in the GNB3 gene, which is linked to the occurrence of both obesity and hypertension.
'Obesity itself not the problem'
According to gastroenterologist, Dr Corn Kruger, obesity itself is not the problem as much as the illnesses associated with it, which include hypertension, diabetes, cardiovascular disease, liver disease and cancer. Obese patients at particular risk are the ones that are predisposed to the metabolic syndrome: hypertension, diabetes and hyperlipidaemia.A person is considered officially obese if their body mass index or BMI exceeds 30 kg/m2. BMI is a measure of body fat based on height and weight. Because obesity is caused primarily by incorrect eating habits and lack of exercise, Kruger says that treatment of someone with a particular form of the GNB3 gene is geared towards changing those aspects of a person's make-up that may cause overeating, sometimes with the help of prescribed medication.Genetic testing for risk of hypertension is recommended because it often causes damage long before diagnosis occurs. However, not all obese patients are advised to get the test. Only those with resistance to previous diets will be referred to a testing facility, in this case GeneCare, explains Kruger.
Empowering the patient
GeneCare Managing Director, Dr Maritha Kotze, says that testing empowers a patient with information so that he or she can take appropriate preventative or remedial action. Obesity has become a global epidemic and a lot of research is being done on the disease. We know why people become obese but not really why some may be more vulnerable to putting on large amounts of weight. However, current methods of treatment are helping in the battle against obesity.In future, genetic testing will be used increasingly to determine who would benefit most from anti-obesity or hypertension drugs.
No quick fix
Both doctors emphasise that there is no quick fix to tackling obesity. Kruger says, obesity drugs currently on the market, which suppress appetites or cut fat absorption, are fairly effective and, unlike those in the past, non-addictive. But they don't present a long-term solution. Side-effects are common, like hypertension, ironically enough.
Although Kruger recommends that obese people do seek help, he says that not all forms of obesity are equally dangerous. It depends on where the fat is distributed. Fat that is centred around the waist rather than the hips - the apple versus the pear shape - is much more worrisome.
Whatever the type of complications arising from obesity, it's still important for those who are overweight to make the appropriate adjustments to their lifestyle: cut out fatty and starchy foods, eat more fruit and vegetables, and get more exercise.
(Source:News24, January 24, 2004)