Discuss pathophysiologic mechanisms by which changes in behavior and lifestyle can improve the health of your patients. (<250 words)

Example 1

Alteration of a number of behaviors can decrease the risk for cancer. Cessation of smoking can greatly reduce morbidity and mortality. Smoking accounts for more deaths than any other cause in the U.S., both from cancer and cardiovascular disease. Cigarette smoke contains many harmful substances. Benzo(a)pyrene can produce mutations through deoxyguanosine adduct formation and can inactivate the p53 tumor suppressor gene. Nitrosamines can induce oncogenic mutations that may destroy GTPase activity. These mutations lead to development of lung carcinomas in persons who have smoked for many years. There is a progression from normal respiratory epithelium to squamous metaplasia to dysplasia to carcinoma. The risk for malignancy decreases upon cessation of smoking. Promiscuous sexual behavior can increase the risk for human papillomavirus infection. The incorporation of HPV DNA into the genome of epithelial cells in the genital tract leads to formation of proteins that can bind or interfere with the function of the tumor suppressor genes Rb and p53. This accounts for the cervical dysplasias and carcinomas seen in persons with lon-standing HPV infection. Abstinence from use of alcohol, or use in moderation, can help to avoid development of liver disease. Persons with a history of chronic alcoholism are at risk for cirrhosis. The regeneration of the hepatocytes that accompanies cirrhosis can favor formation of mutations that lead to hepatocellular carcinoma.

Example 2

Changes in diet and exercise patterns can greatly reduce the risk of impairment and death from cardiovascular diseases. Reducing the amount of total fat in the diet, increasing unsaturated fats, decreasing cholesterol, and increasing intake of fish oils may have many beneficial effects. This can occur through reduction in formation of LDL cholesterol, and oxidized LDL in particular, that is taken up into macrophages in arterial walls. Thus, increased LDL cholesterol favors the formation of fatty streaks that can evolve into fibrofatty plaques that can narrow arteries and become complicated by thrombosis. Coronary arterial occlusion is a major cause for death from myocardial infarction. Increased exercise can reduce fat and increase HDL cholesterol that tends to diminish the risk for atherosclerosis. The reduction in fat through diet and exercise can help to decrease the chance of developing diabetes mellitus type II. Over 80% of type II diabetics are overweight. This is one mechanism for increased insulin resistance that leads to hyperglycemia. Hyperglycemia can promote glycosylation of LDL cholesterol that favors atheroma formation. Diabetics have accelerated atherosclerosis. Hyperglycemia with diabetes can lead to sorbitol accumulation in the cells that do not require insulin for glucose uptake, including nerve, kidney, and retina. This leads to common complications of diabetes such as neuropathy, nephropathy, and blindness. Persons with type II diabetes who lose weight and control their diet and exercise regularly can often avoid these complications.