Carbohydrate Study, Chronic SCI

As people with spinal cord injuries (SCI) get older they become more likely to develop health problems, just like everyone else. However, SCI increases the risk of certain problems. This research project will focus on the control of blood sugar after SCI. Sugar in the blood is the important source of energy for the body. Too much sugar in the blood is known as hyperglycemia and not enough sugar in the blood is known as hypoglycemia. Under healthy conditions, the amount of sugar in the blood is automatically regulated so that a steady level is maintained. After SCI, however, this automatic regulation is damaged. The likelihood of experiencing too much or too little blood sugar is increased. Over time, having too much blood sugar can lead to the development of diabetes. In just the opposite situation, individuals with SCI can begin to experience more frequent episodes of too little blood sugar. It is thought that the level of SCI, amount of time post-injury, and amount of body fat are important factors in the development of hyperglycemia or hypoglycemia. This study will test 2 of those factors, level of SCI and amount of body fat. A total of 35 subjects will be enrolled, 24 with SCI and 11 able-bodied controls. All procedures will be performed at the university's clinical research center. Susceptibility to hyperglycemia will be tested by having each subject drink a sugar water solution and then taking blood samples every 30 minutes for 2 hours. Hypoglycemia will be tested by very carefully inducing low blood sugar, taking blood samples over a 2 hour time period to evaluate different chemicals, and answering a questionnaire about different symptoms experienced during the procedure. Body fat will be measured by having a special kind of x-ray. It is predicted that subjects with cervical injuries and with more body fat will be at the greatest risk of experiencing hyperglycemia and hypoglycemia. The results from this study will provide important information for future studies aimed at examining the effect of exercise and other potentially therapeutic agents on blood sugar regulation in the aging SCI population.