Clinical Nutrition Update 2012

The second annual Clinical Update Symposium featured a compendium of topics that were suggested by a needs assessment conducted among university instructors of medical nutrition therapy. The symposium was designed to provide an update on clinical issues to educators who may not be clinicians or clinicians seeking expertise in new areas of expertise, as well as to provide an update for any attendee wishing to obtain current insight into these topics. The first presentation, “Breast Cancer Survivorship: What Is the Role of Diet and Physical Activity?,” was by Wendy Demark-Wahnefried, PhD, RD. Dr. Demark-Wahnefried provided statistics revealing that the 5-y breast cancer survival rate is 90% and that survivors are at increased risk of cardiovascular disease and more likely to die of cardiovascular disease than breast cancer. Survivors are also at risk of other potentially nutrition-related conditions including weight gain, diabetes, osteoporosis, sarcopenia, and functional decline. New 2012 American Cancer Society lifestyle guidelines for cancer survivorship were presented; these guidelines focus on healthy weight management and prevention of sarcopenic obesity. Dr. Demark-Wahnefried also stated that there is good evidence that exercise can help prevent weight gain and improve body composition in breast cancer survivors. Other discussion points included that there is no known level of safe alcohol use for cancer survivors. Dietary supplement use is common in cancer patients, and although most available data are not from breast cancer patients, there is little evidence of benefit and even some evidence of risk of harm indicated in this limited number of studies. Carole Palmer, EdD, RD, provided the next presentation, “Diet, Nutrition and Oral Health.” Dr. Palmer discussed the interrelationships between oral health and diseases in other organs systems, such as the cardiovascular system, and in systemic disease. Relationships between nutrition and dental and medical issues were presented, including childhood obesity and teen dental caries. Dr. Palmer provided the general caution that, given the often-ignored relationship between oral disease and poor nutrition status, the presence of periodontal disease should stimulate consideration of overall nutrition status and not merely a focus on cariogenic foods. Dr. Palmer stated that current research supports a changing view of cariogenic foods. Cariogenic risk is less due to the amount of sugars consumed but is better explained by how often food components such as orally fermentable carbohydrate or acid are eaten or sipped, as well as by how long they are retained in the mouth. Current research areas include efforts to reduce the cariogenicity of foods; the use of calcium, vitamin D, and naturally occurring antioxidants such as phytonutrients as preventive approaches; and the relationship between oral disease and micronutrient status. The presentation by Nancy Krebs, MD, MS, entitled “Iron Supplementation: When and When Not?,” presented ideas about iron supplementation that might run counter to previous dogma on the treatment of iron deficiency. Basing the discussion on emerging facts about iron homeostasis, she presented clinical cases of acute inflammation associated with celiac disease and chronic deficiency related to gastric bypass surgery to illustrate the complex relationships among inflammation, obesity, and iron status. Recently described concepts of iron homeostasis were presented, including hepcidin physiology and influences on hepcidin of iron deficiency and inflammation. Disorders of absolute iron deficiency vs. iron sequestration were contrasted as well as were disorders including both competing influences. Approaches to the provision of oral vs. parenteral iron supplementation were presented, which include consideration of withholding oral iron supplements in the setting of acute illness likely characterized by elevations in hepcidin and the potential for high oxidative stress. Dr. Krebs discussed the use of both iron and inflammatory markers and stated that the use of hepcidin itself as well as other markers in informing iron therapy is a topic that deserves future attention. Edward Saltzman, MD, presented “Update on Celiac Disease,: which addressed gluten enteropathy and emerging gluten-related disorders. Subclinical or subtle manifestations of celiac disease are now being increasingly recognized, suggesting that many patients with celiac disease remain undiagnosed. Evidence to date supports dietary management of celiac disease by a gluten-free diet for life. Such a diet would exclude wheat, rye, and barley; whether small amount of oats can be consumed remains unclear because some studies have documented no deleterious effects, but most major organizations continue to recommend avoidance of oats. A major concern regarding oats is cross-contamination in processing such that oats would be contaminated with other grains containing gluten. Dr. Saltzman added that the safe level of gluten that can be consumed by patients with celiac disease is below the current level of detection, thus US FDA recommendations are set at the lowest detectable level. Emerging therapies will perhaps provide alternatives to dietary restriction of gluten; the therapies include development of grains not containing gluten, use of oral endopeptidases to digest the immunogenic portions of gluten, ingestion of a benign parasite that interrupts the immunogenic cascade, and a vaccine to improve gluten tolerance. There is emerging evidence that gluten may be associated with disorders other than celiac disease and a newly proposed classification scheme for these disorders was discussed. Thomas Ziegler, MD, concluded the session with an “Update of Hospital Nutrition Support.” Examples of micronutrient deficiencies were provided, and it was emphasized that micronutrient disorders, as well as protein energy malnutrition, should be assessed in hospitalized patients. Dr. Ziegler discussed current indications for oral, enteral, and parenteral nutrition in hospitalized patients, as well as complications of these modalities. Dr. Ziegler reviewed recent trials of novel approaches to nutrition in this population, including the use of glutamine dipeptides, single or combination antioxidant nutrients, and new lipid formulations. The resurgence of investigations assessing parenteral glutamine in critically ill patients was discussed, and it is now recommended by some that provision of this conditionally essential nutrient, if available, be considered in this population. Dr. Ziegler concluded with an approach to the provision of nutrition and provided caveats about refeeding and overfeeding syndromes.