[Prediction of erectile dysfunction in patients with localized prostate cancer undergoing radical prosta- tectomy].

Introduction: Penile rehabilitation strategies have been developed to accelerate and improve the recovery of erectile function after radical prostatectomy. However, the differential efficacy and the best penile rehabilitation strategy are still unclear. Therefore, the search for factors influencing the prognosis of erectile dysfunction (ED) one year after radical prostatectomy and the formulation of algorithms for patient management is highly relevant.

Aim: To analyze pre- and postoperative factors that affect erectile function after radical prostatectomy with the development of an algorithm for calculating the risk of developing ED.

Materials and methods: A total of 104 patients with localized prostate cancer who underwent nerve-sparing prostatectomy were retrospectively examined. A year after surgery, regardless of whether medicinal penile rehabilitation was used or not, patients were divided into two groups depending on the possibility of having sexual intercourse.

Results: The following indicators were identified as predictors of an unfavorable prognosis using multiple regression analysis with a stepwise inclusion method: age, erectile function assessed using the International Index of Erectile Dysfunction-5 (IIEF-5) before surgery, the presence of type 2 diabetes mellitus, use of phosphodiesterase type 5 (PDE-5) inhibitors in the postoperative period, type of radical prostatectomy (unilateral or bilateral nerve sparing). It was found that the presence of factors such as the older age, type 2 diabetes mellitus and a lower preoperative IIEF-5 score were associated with lower IIEF-5 score after a year. Taking PDE-5 inhibitors for a year and bilateral nerve-sparing RP increased IIEF-5 score. Of the five factors presented in the model, four (patients age, presence/absence of diabetes mellitus, IIEF-5 level before surgery) were not controlling factors, since they could not influence the choice of rehabilitation method. The indicator reflecting the fact of taking PDE-5 inhibitors during the year was a controlling factor, since its inclusion in the model allowed to choose the appropriate method of rehabilitation for the patient. The multiple correlation coefficient is 0.898, which characterizes the high predictive level of this model. The data obtained were converted into an algorithm that allowed to calculate the risk of developing ED, taking into account modern methods of treatment and rehabilitation, and make the right decision in choosing the optimal strategy for further rehabilitation interventions.

Conclusions: From the presented data we can conclude that the prognosis for the development of ED after radical prostatectomy can be determined with high reliability based on the following risk factors: the type of surgical treatment, namely bilateral nerve sparing, affects the preservation of innervation, which affects the postoperative restoration of erectile function. The use of PDE-5 inhibitors helps restore erectile function only in a certain category of patients. The older age, type 2 diabetes mellitus and erectile dysfunction at baseline (IIEF-5 value) aggravate ED in the postoperative period. Thus, taking into account these risk factors, it is possible to determine an individual management strategy for the patient and provide optimal and timely treatment, which will preserve the quality of life and effectively use medical resources.