Urine pH and imaging findings of prostate useful predictors of prolonged duration of hematospermia

Background: Few investigations regarding hematospermia duration have been reported thus far. The aim of this study was to identify clinical factors associated with the duration of hematospermia. Methods: Clinical data of 198 patients with hematospermia treated at Toho University Omori Medical Center from 2007 to 2022 were retrospectively evaluated. To identify independent predictors of hematospermia duration, uni- and multivariate Cox analyses were performed. Receiver operating characteristic analysis, Kaplan-Meier survival curves, and propensity score matching were applied for statistical evaluations. Results: Multivariate analysis of all 198 patients showed urine pH (UpH) level and any abnormal imaging finding of the prostate to be independent predictors of hematospermia duration. Based on the receiveroperating curve of UpH level for hematospermia improvement, the patients were divided into two groups using a threshold of 6.0 (Low-UpH 5.0-6.0, n=128; High-UpH 7.0-9.0, n=70). Kaplan-Meier curves indicated that patients in the High-UpH group or with any abnormal imaging finding had a higher rate of hematospermia persistence (both P<0.05). Even after matching between the groups classified by UpH (n=60 each), multivariate analysis showed that UpH level (hazard ratio 0.75, 95% CI: 0.61-0.92; P=0.006) and any abnormal imaging finding (hazard ratio 1.55, 95% CI: 1.04-2.31; P=0.033) were independent predictors of hematospermia duration. In Kaplan-Meier analysis findings of matched cohorts, High-UpH and presence of any abnormal imaging findings remained significantly correlated with higher rate of hematospermia persistence, while further stratification using a combination of these two factors identified a stepwise reduction in that rate (P=0.019). In addition, the proportion of patients with these two factors present simultaneously was significantly higher in the group with hematospermia for two months or more, and especially with a duration of greater than six months, than in the group with a duration of less than two months. Conclusions: Although further research is needed, both UpH level and imaging findings of the prostate are considered useful biomarkers for predicting prolonged hematospermia.