In a study of 430 patients treated for active tuberculosis (TB) between 1990 and 1999 at the Montreal Chest Institute, Canadian investigators found that 37 persons had serious adverse reactions to their prescribed medications, with 9 suffering a second major reaction. The highest risk groups for side effects were females, those over 60, and individuals born in Asia. The treatment agents studied were isoniazid, rifampin, pyrazinamide, and ethambutol. Of the 37 patients suffering serious adverse events from their medication, 20 were placed in the hospital for an average stay of 16 days. One patient was hospitalized twice for an adverse drug reaction. In addition, 29 of the 37 patients who developed serious side effects made a total of 91 extra clinic visits. Also, the TB clinic nurse had an additional 30 home visits to 8 of the patients.
An expert, Richard E. Chaisson, M.D., of the Center for Tuberculosis Research, Johns Hopkins Medical School, Baltimore, Maryland, in an editorial on the study, wrote that toxicity during TB therapy is a real problem that can cause serious harm to patients. He points out that the adverse events which occurred in this study were by no means trivial; all required an alteration in therapy and 5 percent of the patients were hospitalized for an average of 16 days. He notes that toxicity added substantially to the cost of care, and that the treatment of the individuals was prolonged by an average of 5 months. He also indicates that after years of neglect the TB drug field has re-ignited over the past several years with university-based investigators actively pursuing important new therapeutic agents. The study and editorial appear in the first issue for June 2003 of the American Thoracic Society's peer-reviewed American Journal of Respiratory and Critical Care Medicine.
PERFORMANCE DIFFERENCES SHOW LACK OF STANDARDIZATION FOR SIX-MINUTE WALK TEST
Patients suffering from severe emphysema who took a second six-minute walking test, a procedure widely used to evaluate functional status in lung disease, showed a statistically significant improvement from the second test averaging 7 percent in distance walked; researchers also found that the shape of the walking course definitely affected the final result. The individuals involved were 761 participants in the National Emphysema Treatment Trial who took the test at 17 clinical centers. For 470 of the initial enrollees, the test was repeated on the day after the first test. The investigators note that there are differences in the testing techniques among the various clinical centers and laboratories. There seemed to be no agreement about the length of the test course, the shape of the course (straight (out and back) versus continuous circle or oval), whether a practice test should be done before the final test, and whether the better of two walks or the second of two walks should be the reported value. In addition to the distance walked improving by 7 percent on the second test, the investigators found that a continuous course, either circular or oval, added over 92 feet to the walking distance compared to a straight out and back course. The study is published in the first issue for June 2003 of the American Thoracic Society's peer-reviewed American Journal of Respiratory and Critical Care Medicine.
For the complete text of these articles, please see the American Thoracic Society Online Web Site at http://www.atsjournals.org. For either contact information or to request a complimentary journalist subscription to ATS journals online, or if you would like to add your name to the Society's twice monthly journal news e-mail list, contact Cathy Carlomagno at 212-315-6442, or by e-mail at ccarlomagno@thoracic.org.
Journal
American Journal of Respiratory and Critical Care Medicine