This is an excerpt from Physical Activity and Type 2 Diabetes eBook by John Alan Hawley & Juleen R. Zierath.
Type 2 diabetes differs from type 1 diabetes, previously called insulin-dependent diabetes mellitus (IDDM), which usually manifests much earlier in life with a distinct pathogenetic profile. Until just before 2000, type 2 diabetes was regarded as a disease of middle-aged and elderly individuals (hence the name adult-onset diabetes). However, once teenagers began displaying clinical cases of type 2 diabetes, largely due to concurrent increases in childhood obesity and sedentary lifestyle, the terminology adult-onset was discarded, for it was no longer a disease confined to adults. Noting the escalating increases in sedentary living (Brownson, Boehmer & Luke, 2005), the 2004 International Diabetes Federation Consensus Workshop (Alberti et al., 2004) indicated that within 10 years, type 2 diabetes will be the predominant form of diabetes in many ethnic groups of children worldwide, surpassing type 1 diabetes in prevalence in children. The global figure of all people with diabetes, including adults, is skyrocketing. It is now 150 million and is predicted to rise to 300 million in 2025, with 75% of the cases occurring in developing countries (King, Aubet & Herman, 1998).
According to the U.S. National Institutes of Health (NIH), type 2 diabetes directly contributes to the following conditions:
- Heart disease and stroke. Adults with diabetes have death rates due to heart disease that are 2 to 4 times greater than rates for adults without diabetes. The risk for stroke is 2 to 4 times higher among individuals with diabetes.
- High blood pressure. About 73% of adults with diabetes have blood pressures greater than 130/80 mmHg.
- Blindness. Diabetes is the leading cause of new cases of blindness among adults aged 20 to 74.
- Kidney disease. Diabetes is the leading cause of kidney failure; 150,000 people with diabetes live on chronic dialysis or with a kidney transplant.
- Nervous system disease. Over 50% of individuals with diabetes have impaired sensation or pain in the feet or hands, slowed digestion in the stomach, carpal tunnel syndrome, and other nerve problems. A severe form of diabetic nerve disease is a major factor in lower-extremity amputations.
- Amputation. Of nontraumatic lower-limb amputations, 60% occur among individuals with diabetes.
- Dental disease. About one-third of individuals with diabetes have severe periodontal diseases with loss of gum attachment to the teeth measuring 5 mm or more.
- Pregnancy complication. Mothers with diabetes have a greater number of spontaneous abortions, and their babies have an increased risk of major birth defects and of developing diabetes later in life.
- Immune system disorder. People with diabetes have a reduced ability to reject bacterial and viral infections and are more likely to die from pneumonia or influenza than are people who do not have diabetes.
Besides resulting in associated health costs, diabetes creates tremendous economic costs. In 2002, the American Diabetes Association estimated that the indirect costs of diabetes in the United States were $132 billion U.S. (Hogan, Dall & Nikolov, 2003). Direct expenditures were $92 billion U.S., or about 5% of the nearly $1.9 trillion U.S. annual total health care costs. The medical expenditure for an individual with diabetes was $13,243 U.S., as compared to $2,560 U.S. for those without diabetes. Even when adjusted for differences in age, sex, and race or ethnicity, medical expenditures were about 2.5 times higher in an individual with diabetes than in a person without diabetes. This economic strain leads to other adverse consequences, such as diverting scarce monies from research in order to pay for health care. Biomedical research (and hence funding for the research) is needed to help alleviate the diabetes burden, but at the same time, funds are also needed to treat patients who already have the disease, setting up a vicious cycle. In the United States, the health care industry consumes about $1 in every $6 spent. By 2015, health care will use $1 of every $5 spent, which is a 20% jump. Increasing health care costs will redistribute monies from other areas (including research on diabetes), further lowering the quality of life for most individuals
Eliminating or minimizing the health problems produced by diabetes could significantly improve the quality of life for patients with diabetes and their families while at the same time diminish health care costs and thus enhance economic productivity (Hogan, Dall & Nikolov, 2003, 10). It is in this arena that the old axiom that prevention is better than cure rings truer than ever. One powerful weapon for prevention is to reintroduce physical activity into daily living in order to curb the rise in health care costs.