CHAPTER 9 Chronic Disease Prevention 229 Box19-1 Four Pathophysiologic Pathways in Chronic Disease I. Cellular Senescence 3. Oxidation Aging, or senescence, at the organ system and cellular levels encom ation with the health-promoting potential of antioxi asses gradual attenuation of function (.g, age-related decline in es from the harmful potential of oxygen free radicals glomerular filtration rate)and ultimately a termination of cellula both in defense of the body against pathogens and as a renewal and the loss of formerly functional cells through apoptosi t of metabolic activity, Oxidation is implicated as a facilita rogrammed cell death). Chronologic and biologic aging are related but different, Chronologic aging refers to a measure in units of actua time, biologic aging refers to function relative to age-standardized 4. Inflammation norms By either measure, the time-dependent attenuation of func- Inflammation is a generic term referring to a range of immune tional capacity is a common element in the development and pro- gression of chronic diseases. system actions, both in response to and independent of infection. The action of various white blood cell lines, cytokines, immu globulins, and 2. Degeneration complement can defend the body against pathogens but can also cause damage to native tissue and healthy cells. Dietary Degeneration can occur as a time-dependent process but can also occur imbalances, with resultant hormonal imbalances, related in particu independently. Cumulative injury to the lining caused by lar to eicosanoids(prostaglandins), cortisol, and insulin, are impli- hypertension is an example of degeneratio theerosion of articu- cated in chronic inflammation, which in turn is implicated in the lar cartilage caused by"wear and tear" that osteoarthritis propagation of most chronic disease. Common to most if not all chronic diseases. These processes provide important insights about the potential to prevent chronic disease, as well as opportunities to prevent multiple chronic diseases by addressing a common cluster of causes ox 19-2 Ten Controllable Factors in %o of cancer are thought to be preventable with the use of resources already Prevention of Chronic Disease available. Were this knowledge to be translated into the power of routine action, it would increase life expectancy Toxic agents and add much more to health expectancy, or the health Firearms span. 4 In blunt terms, if and when we find the means to Activity patterns exual behavi Motor vehicles turn what we know about the prevention of chronic disease Microbial agents into what we routinely do, it would constitute one of the most stunning advances in the history of public health(see Chapter 28) Modified from McGinnis JM, Foege WH: JAMA 270: 2207-2212, I. CONDITION-SPECIFIC PREVENTION A. Obese These effects-the chronic diseaseswere the result of 10 There is debate about the appropriateness of classifying factors, mostly behaviors that individuals can control(Box obesity as a chronic disease. Obesity is clearly established as 19-2). Using the epidemiology of 1990, this analysis found a risk factor for virtually all major chronic diseases. Whether that about 80%of all premature deaths were attributable to obesity itself qualifies as a disease is important in several the first three entries: tobacco, diet, and activity patterns ways. First, obesity bias is a prevalent and pernicious influ- (physical activity ). Alliteratively, the leading causes of chronic ence, and the establishment of obesity as a true medical disease and premature death in 1990 were "how we used our condition defends against this in the form of legitimacy. The feet, our forks, and our fingers codification of obesity as a disease implies that, as with other In 2004 the U.S. Centers for Disease Control and Preven diseases, it is (at least relatively) inappropriate to"blame the tion(CDC)updated and supported the same fundamental victim. Studies, on in adi, recent and ac umulating evidence identification of obesity as a disease facilitates its inclusion indicates that lifestyle interventions can modify gene expres among conditions with medical insurance coverage. The sion and thus alter the risk for chronic disease development International Classification of Diseases(ICD) coding system and progression at the genetic level. 2 In the aggregate, this used for billing third-party payers assigns a"diagnostic code' re belies the importance of the nature/nurture debate to any given condition. Obesity must be recognized among slighting the hegemony of " epigenetics"and the candidate conditions for such coverage to be processed. The apparent human potential to"nurture nature U.S. Department of Health and Human Services initially he available data from diverse sources suggest that about desi disease with this in mind, and rele. 80%of all chronic disease could be prevented. with regard vant progress has followed. In 2011 the Centers for Me to specific conditions, 80%or more of cardiovascular disease; and Medicaid Services( CMS)authorized reimbursement for