Estimate criteria for efficacy of treatment in benign prostatic hyperplasia

Abstract

Background: Various treatment modalities for benign prostatic hyperplasia (BPH) have emerged and are now in use or await evaluation of clinical usefulness. It is difficult, however, to compare their efficacies on a single scale, because standardized criteria for therapeutic efficacy of BPH treatments have not been established.

Patients and methods: A total of 692 BPH patients from 8 institutions in Japan received various treatments, and were judged by specialized physicians for overall efficacy, and for efficacy in 4 domains: symptom, function, anatomy, and quality of life (QOL). Efficacy of treatment was graded as excellent, good, fair or poor, and assessed using items based on conventional clinical measurements. These items included 1) the difference (post-pretreatment value), 2) relative ratio (post/pre) and, 3) the individual values of pre- or posttreatment measurements. The cut off levels for each grade were heuristically selected by Spearman's rank correlation and multiple regression analysis so that the results accurately predicted physicians' judgement, while the feasibility was maintained.

Results: The results for each efficacy grade (range of excellent, range of good, range of fair, range of poor) were summarized as follows: Symptom: (post/pre treatment ratio of I-PSS) < or = 0.25, < or = 0.5, < or = 0.75, > 0.75. Function: (post-pre of Qmax) > or = 10 mL/s, > or = 5 mL/s, > or = 0.25 mL/s, < 0.25 mL/s. Anatomy: (post/pre ratio of prostate volume) < or = 0.5, < or = 0.75, < or = 0.9, > 0.9. QOL: (pre-post of QOL index) > or = 4, 3, 2 and 1, < or = 0. The overall efficacy grade was defined as the median of efficacy grades of 3 domains: symptom, function and QOL. The agreement rates between the criteria and physicians' judgement on the dichotomous efficacy (either excellent plus good, or fair plus poor) were approximately 80% in individual domains and overall estimate, and consistent among various treatments.

Conclusion: The proposed criteria are fairly accurate, simple, and practical, and thus may be useful as a standard method for assessing the clinical efficacy of BPH treatments.