TOTAL PARENTERAL NUTRITION: LARGER-SCALE CLINICAL TRIALS NEEDED

Executive Summary

TOTAL PARENTERAL NUTRITION: LARGER-SCALE CLINICAL TRIALS NEEDED to determine efficacy in enhancing cancer treatment, Robert Torosain, MD, University of Pennsylvania, suggested at a Jan. 10-11 conference on "Evaluating Total Parenteral Nutrition," sponsored by Georgetown University's Program on Technology and Health Care. "There are many laboratory research models which have demonstrated improved outcomes [from TPN] in terms of morbidity and mortality through the use of nutrition support...in tumor-bearing animals being treated with chemotherapy or undergoing radiation therapy," Torosain said. However, "there are major problems with 90% of the clinical studies that have been done." Torosain cited a number of problems, including inadequate numbers of patients, inadequate pretreatment and amounts of TPN given, and heterogeneous study groups. Noting that up to 40% of all hospital patients are malnourished and that cancer patients are the "most malnourished," Torosain said that seven of nine studies he reviewed indicated that weight gain is associated with improved survival for cancer patients. * Areas of needed research on TPN will likely be addressed in a conference report to be prepared by a seven-member panel, headed by Harvard Technology Assessment Group Director Frederick Mosteller, MD. Aside from evaluating TPN specifically, Georgetown, under an HHS contract, convened the session to test a "forum" approach to group review of a technology. The format differs from a consensus development conference in two key ways: participants were directed to assess the state-of-the-art of TPN but not necessarily to reach consensus, and rather than completing work by the session's end, the panel will continue to review both the conference discussion and additional materials. Within four to six weeks, the panel will draft a "core statement" on uses of TPN for various diseases, as well as a more comprehensive review of the technology. After comment from meeting participants, the statement and report will be issued to the public. Georgetown will submit those documents, plus its assessment of the forum approach to HHS later in the year. One of the largest studies of TPN is a yet-unpublished randomized clinical trial conducted by the Veterans Administration. The study assesses use of pre-operative TPN for 259 patients, who were followed for 90 days after surgery. VA researcher George Reinhardt reported that the TPN and control groups had similar rates of mortality (13.4% v. 10.5%) and major complications (25.5% v. 24.6%). However, TPN patients had more infection-related complications while the control group had more noninfection complications. At 30 days post-surgery, 14.1% of the TPN group experienced infectious complications compared to 6.4% of the control group. Noninfectious complications were experienced by 16.8% of the TPN group and 22.7% of the controls. However, the increased rate of infections was confined to the subgroups of TPN patients who were well-nourished or mildly malnourished, and those patients did not receive a demonstrable benefit from pre-operative TPN. "Severely malnourished patients experienced fewer noninfectious complications with TPN and pre-operative TPN should be limited to those most severely malnourished...patients unless other specific indications for TPN exist," a summary of the study concludes. Regarding costs, Johns Hopkins University Researcher Gerard Anderson, PhD, reviewed his 1985 study finding that use of TPN added $10,000-$30,000 to costs of hospital care for a Medicare beneficiary, depending on the diagnosis-related group used for billing. Only $3,000-$8,000 of those added costs were due to the TPN therapy, with the rest due to lengthier stays and other factors. Anderson suggested that the need for TPN may signal that a patient is more ill than the average patient in a Medicare DRG. On the outpatient side, Medicare is spending about $200 mil. per year for 6,000 patients, or about $33,000 per patient, according to Marilyn Koch, Health Care Financing Administration Office of Program Administration director. This includes TPN solutions, supplies, and nursing care, but not physician fees.