Obesity: Burdens of illness and strategies for prevention or management

Obesity is a progressive disease of unwanted fat accumulation which has mul tiple, organ-specific pathological consequences. The manifestations of obes ity occur within Virtually every subspecialty of medicine or surgery and th ey interact importantly to accelerate the ageing process in many organs. Ma ny of the hazards of obesity have multiple causes (e.g., diabetes, heart di sease, stroke, colonic and breast cancer, urinary incontinence, tiredness, back pain, breathlessness). All of these conditions become more prevalent w ith age and are also more prevalent among overweight persons, particularly those with a central fat distribution marked by a high waist circumference. Hypertension may be caused or aggravated by weight gain. It is mediated by the physical demands of an expanded circulating volume and increased metab olic rate by metabolic mechanisms related to central fat distribution and t he "metabolic syndrome", and to increased sodium consumption by overweight people (because they need more food to maintain a higher metabolic rate). S ince body mass index (BMI) and waist circumference increase significantly w ith age there is an escalation of the burden of ill health from obesity wit h age. The best simple indicator of disease risk with obesity is the waist circumference since this identifies people who have a high body fat content and also those who have an increased intraabdominal accumulation of fat. T he quantitative burden of ill health from overweight and obesity Varies wit hin different specialties, but up to 80% of type 2 diabetes or polycystic o varian syndrome can be attributed to obesity. Obesity is the cause of sleep apnea syndrome in around 50% of cases and heart disease in perhaps 10-20% of cases. In Scotland 80% of people with existing cardiovascular disease ar e overweight compared with 57% of the general population. The financial bur den to health services from overweight and obesity has been incompletely as sessed, although it is estimated that around 4% of total health care budget s are attributable to people having BMI > 25 kg/m(2). This is similar to th e entire cost of diabetes, epilepsy or major cancers. Obesity is therefore an extremely expensive disease based on these conservative estimates from l imited evaluations. More general assessments show how obesity increases the amount of time taken off work, the number of drugs prescribed and the expe nditure from social services support. Thus, obesity represents a huge burde n not only on the individual patient - physically, psychologically, sociall y and financially - but also on families and careers and is a huge drain on health care resources. Overweight affects well over half of all adults wor ldwide, progressing to BMI > 30 kg/m(2) in around 20% outside subsistence r ural communities. Its rapidly increasing prevalence now described as an epi demic demands major preventive measures, as well as better medical treatmen t for individuals affected. (C) 2000 Prous Science. All rights received.