Sunday, April 21, 2002		Fitness

Obesity in childhood can lead to diabetes

DIABETES is in news. It has, in fact, never been out of news because of its overwhelming presence in the population, particularly in our own country. There are nearly 60-70 million diabetics in the world out of which nearly 30 million are in India. According to W.H.O. projections, by the year 2025 there will be 300 million individuals affected by the diabetes worldwide out of which over 70 million will be in India. According to a recent study conducted in various metropolitan towns of India, the prevalence of diabetes in the country is frightening. Nearly 12 per cent of the adult population in Delhi and Kolkata, nearly 10 per cent in Mumbai, 12.5 per cent in Bangalore, 13.5 per cent in Chennai and near 16 per cent in Hyderabad are patients of diabetes. It has been repeatedly stressed that lifestyle factors like nutrition and lack of exercise are important factors in the rapid rise of this disease which plays a very important role in the genesis of heart disease, kidney failure, blindless and ischemia of the limbs. On the World Health Day April 7, the WHO adopted Lifestyle as its theme and "Move for Life" as its slogan for the year.

More information is, however, becoming available through research being conducted on the various factors leading to this disease. In a paper published by Parson and his colleague in the December issue of the British Medical Journal last year, the results of a long follow-up of children from birth to 30-35 years have brought out certain factors during early childhood that lead to diabetes in later life. In a meticulous analysis of the children whom they followed from birth through their early adulthood, the researchers found that heavy mothers give birth to bigger babies who later on become obese adults. They also found that, paradoxically, the babies who have a low birth weight tend to grow rapidly in childhood and become obese adults. This phenomenon is already noticeable in the developing countries where with availability of better nutrition, particularly for boys, there are sudden spurts of growth leading to obesity which in turn is an important factor in the development of diabetes. According to this paper the critical period of growth for the children is early childhood and indeed even earlier than that, the intrauterine life. These observations point towards the possibility of intervention during these phases of life which makes more economic and medical sense than developing drugs for diabetes.

The second piece of information has come from a research paper from the Yale University published in the March 2 edition of the New England Journal of Medicine. The researcher studied a group of obese children between the age of 4-10 years and adolescents between the age of 10-19 years to test the potential of diabetes in these children. They carried out what is known as the glucose tolerance test. In this test, the blood sugar is tested by giving a certain amount of glucose orally and then measuring the ability of the children to handle this glucose load. They also measured the insulin level and the response of insulin secretion after the administration of glucose. It may be mentioned that in the early stages of diabetes testing simple fasting blood glucose or even glucose levels after food may not give adequate evidence of presence of diabetes mellitus. But this test puts more pressure on the beta cells of pancreas-secreting insulin and thus brings out their potential to the maximum. The results were startling. Twenty five per cent of obese children between the age of 4-10 years and 20 per cent of adolescents had abnormal glucose levels after they were given the glucose. They also found that the insulin levels in their blood were higher. Indeed, 4 per cent of the children had diabetes as well. The fasting glucose level in the children was not high to begin with. This test indicates that although on testing the blood glucose levels appeared to be normal but stressing the system by giving higher dose of glucose brings out the presence of diabetes.

The results of this study are, indeed, very meaningful and worrisome. The kind of diabetes, which we refer to as type-II diabetes or non-insulin dependent diabetes, usually starts after the age of 30. These results would indicate that these children are already becoming type-II diabetics and would, therefore, greatly increase the number of people suffering from this disease. These results are not merely based on theoretical considerations but are a potential warning of the things to come. In the USA, nearly 30 per cent of diabetics below the age of 20 suffer from type-II diabetes. In some areas of Japan, more than half of the diabetics among children also suffer from this disease. It may be mentioned that ordinarily the type-1 diabetes in children is of a different nature where beta cells of the pancreas do not secrete any insulin as a result of certain genetic and immunological factors. This type of diabetes was considered synonymous with childhood diabetes. Its symptoms include increased thirst and appetite, excessive urine formation and loss of weight. Incidentally, the study also has lessons for the medical profession and means that if we want to rule out diabetes in a child or adult, particularly those who are overweight, the fasting glucose level is not enough and an appropriately conducted glucose tolerance test is necessary to rule out the presence of diabetes.