Evidence-based medicine in herbal treatment: Benefit to assess quality of life (QOL)

Abstract

Oriental medicine (including Kampo medicine) treats patients on the basis of their overall symptoms and conditions, and plays an important role in tailor-made medicine. In Oriental medicine, the condition of "acquiring a disease" is known as mibyo. The concept of treating mibyo is similar to that of improving health-related quality of life (HRQOL) which has been defined and developed in Western medicine as a subjective assessment of health-based factors from on the patient's perspective. HRQOL has been broadly defined to include the physical, psychological, social aspects of health perception and functioning. Many HRQOL scales have been developed by clinicians to assess the effect of therapeutic or preventive intervention. HRQOL scales are questionnaires for the patients, and are thus patient-reported (self-administered).
Kampo medicine is a multi-component drug system comprising more than one crude drug; however, compared with Western medicine, there is insufficient evidence in literature regarding this as it is a unique treatment system. Oriental medicine researchers have been actively discussing measures to strengthen the levels of evidence of Kampo medicine; therefore, data from randomized clinical trials (RCTs) have increased. We investigated QOL data availability in domestic and international studies regarding crude drug products. Of 1995 international studies, 39 studies evaluated QOL from international researches. For domestic research, Evidence Report of Kampo Treatment 2010 and Appendix 2011 by special committee for Evidence-based medicine (EBM), The Japan Society for Oriental Medicine (JSOM), Evidence Report/ Clinical Practice Guidelines (ER/CPG-TF) summarized total 359 RCTs and one meta-analysis, 21 reports evaluated QOL, 17 reports were published after 2000. Our evaluation of these domestic and international studies suggests that QOL assessments have gradually gained widespread recognition. The levels of evidence for Kampo medicine have been increasing; however, QOL data are still very limited. The limited levels of evidence for QOL may be due to low QOL awareness, the difficulty to select QOL scale or the target patient population, and the difficulty to obtain a large number of participating patients.