A comparison of techniques for eliciting patient preferences in patients with benign prostatic hyperplasia.

PURPOSE: We compared the Health Utility Index (HUI), EuroQol (EQ-5D) and time trade-off methods to identify the most suitable technique for collecting preference data in a clinical trial of patients with benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: A total of 29 men with symptomatic BPH were interviewed by a single trained interviewer who collected demographic data and administered EQ-5D and time trade-off questionnaires. Participants self-administered the HUI and a symptom severity index, the International Prostate Symptom Score (I-PSS) questionnaire. Utility values for current patient health states obtained from the HUI, EQ-5D and time trade-off questionnaires were compared and their relationship with I-PSS data was examined using Spearman's correlation coefficients. Administration time and patient assessments of the relevance of the questions were also compared for the 3 methods. RESULTS: Although mean utility values for HUI, EQ-5D and 1-year time trade-off were similar, only utility values elicited using time trade-off with a 1-year time frame significantly correlated with symptom scores. The 1 and 10-year time trade-off derived values were reasonable predictors of the I-PSS with multiple correlation coefficient values of 0.379 and 0.265, respectively. All participants indicated that the HUI and EQ-5D were appropriate for assessing BPH, while approximately 10% considered time trade-off questions irrelevant. Average completion time for the HUI, time trade-off and EQ-5D questionnaires was 31, 25 and 10 minutes, respectively. CONCLUSIONS: Because only time trade-off resulted in utility values that significantly correlated with symptom scores, we recommend its use for estimating utility in clinical trials of BPH.

TGFbeta induces morphological and molecular changes similar to human anterior subcapsular cataract.

BACKGROUND: Transforming growth factor beta (TGFbeta) has been shown to induce subcapsular plaques in cultured rat lenses as well as in lenses of transgenic mice. In the present study the authors have extended their analysis of these cataract models to determine how closely they mimic human cataract. In particular, they studied the maturation of cataract in the transgenic model to determine if it develops similar features as previously described for anterior subcapsular cataract (ASC) in humans. Furthermore, they investigated whether both of these animal models express the range of molecular markers that have now been shown to be present in human ASC. METHODS: Histology and periodic acid Schiff staining were used to study the development and maturation of subcapsular plaques in transgenic mice overexpressing TGFbeta1 in the lens. Immunolabelling methods were used to identify the molecular markers for ASC in both the transgenic mouse model and in rat lenses cultured with TGFbeta2. RESULTS: Histological analysis showed that the subcapsular plaques that develop in adult transgenic mouse lenses bear a striking similarity to mature human ASC, including the formation of a new epithelial-like layer extending between the subcapsular plaque and the underlying fibre mass. All known molecular markers for human ASC were induced in both rodent models, including collagen types I and III, tenascin, and fibronectin. They also identified the presence of desmin in these plaques, a putative novel marker for human cataract. CONCLUSIONS: In both transgenic mouse and rat lens culture models TGFbeta induces markers similar to those found in human ASC. Atypical expression of these cataract markers is also characteristic of posterior capsular opacification (PCO). The molecular markers expressed are typical of a myofibroblastic/fibroblastic phenotype and suggest that a common feature of ASC and PCO may be induction of an epithelial-mesenchymal transition by TGFbeta.