Disabling obesity: from determinants to health care models

Obesity is currently regarded as one of the major health challenges of the developed world. Excess body weight is an important risk factor for morbidity and mortality from cardiovascular diseases, diabetes, cancer, musculoskeletal disorders and even psychiatric concerns. Obesity is estimated to cause nearly 3 million deaths per year worldwide. Several epidemiological studies in the last two decades have shown that adiposity, as measured by body-mass index (BMI), has increased in many populations and it has been argued that this could reverse life-expectancy gains in high-income nations. Unlike many other conditions, obesity is hard to define quantitatively. BMI, the most commonly used measure of obesity, fails to actually measure the amount and distribution of fat mass, the crucial factor for the risk of developing some of the obesity-related comorbidities. High-quality studies point out that patients classified as simply overweight according to BMI are in fact obese when we take into consideration the actual measure of fat mass by air plethysmography. Also, obesity is not necessarily associated with comorbidities: there are indeed metabolically healthy obese individuals. Thus, we need to consider separately individuals presenting simple obesity from those at risk of developing or who have already developed complex clinical situations potentially leading to disability. Comorbidities can tip the balance of independence in patients who already have functional limitations due to the excess of mass itself (reduced tolerance to effort, reduced muscle strength and power, reduced balance) or who develop conditions secondary to abnormal metabolism of adipose tissue (diabetes, cardiovascular conditions, non-alcoholic fatty liver disease) or to a combination of the two (sleep apnea). Those patients, like others suffering from chronic conditions characterized by relapses and sudden precipitation of the clinical-functional picture (i.e. neurodegenerative and rheumatic conditions), may enter phases of disability, which require a “here and now” multidisciplinary approach to avoid or minimize the progressive worsening of obesity, its comorbidities and, ultimately, disability. Morbid obesity with comorbidities leading to disability represents the real social and economic burden for the National Health Systems worldwide. Also, the presence of multiple and associated comorbidities often represents an obstacle to being admitted to clinical settings for the treatment of metabolic diseases. On the other hand, clinical units with optimal standards for the treatment of pathological conditions in normal-weight patients are often structurally and technologically inadequate for the care of patients with extreme obesity. The evaluation and treatment of patients with disabling obesity requires clinical facilities where these complex patients can be treated with appropriate therapeutic and rehabilitative protocols carried out by specially trained operators and within an environment, which is ergonomically adequate and safe for both patients and staff alike. Given the magnitude of the problem, it is not surprising that thousands of books have been published about epidemiological, genetic, molecular, pathophysiological and obviously therapeutic aspects of obesity. The aim of this book is to focus on the pathophysiological and rehabilitative aspects of disabling obesity, highlighting multidisciplinary rehabilitation interventions as key to counteracting the disabling aspects of complicated obesity. After an overview of the current knowledge of epidemiology and of genetic and environmental determinants of obesity, the first chapters intend to define the general features of obesity-related disability and how it can be measured. The final chapters will deal with the most advanced treatment protocols for the related specific clinical conditions and the existing evidence of effectiveness. We do hope that this book will help to spread seminal ideas about the relevance of creating clinical units adequately equipped to face the various clinical pictures of disabling obesity and provide a whole range of intensities of rehabilitation care, from intensive in-patient interventions to the planning of long-term out-patient treatments. At present, we are very aware that obesity cannot be cured but, especially because of that, we should target our efforts on preventing the progression of the disease, its comorbidities and the related disability.