Carotid artery intima media thickness can predict the response to phosphodiesterase 5 inhibitors in patients with moderate erectile dysfunction

Background Increased carotid artery intima-media thickness (CIMT) has been shown to be associated with erectile dysfunction (ED), but studies evaluating the efficacy of CIMT in predicting drug response are lacking in the literature.Aim We aimed to evaluate the efficacy of CIMT in predicting the response to phosphodiesterase-5 inhibitors (PDE5-I).Methods A total of 274 subjects were divided into two groups: ED patients (n = 150) and controls (n = 124). The patients in the ED group were further divided into the subgroups of severe, moderate, mild-moderate, and mild ED. Blood tests, carotid ultrasonography, and the International Index of Erectile Function-5 (IIEF-5) diagnostic tool were applied to all subjects. Tadalafil was administered to each patient. The patients were re-evaluated using the IIEF-5 questionnaire after 2 months of treatment. According to their response to medication, the patients were evaluated as responders or nonresponders.Outcomes Increased CIMT was significantly associated with the failure of PDE5-I therapy, especially in patients with moderate/mild-moderate ED.Results Fasting blood glucose, body mass index, and CIMT were significantly higher in the ED group compared to the control group (P = .021, P = .006, and P < .001, respectively). The IIEF-5 score was significantly lower in the ED group (P < .001). CIMT was significantly correlated with the IIEF-5 score. When the total patient group was evaluated, the CIMT value of the responders was significantly lower than that of the nonresponders (P = .001). CIMT was significantly higher among the nonresponders with moderate/mild-moderate ED compared to the responders (P = .004 and .008, respectively), while there was no significant difference in CIMT between the responders and nonresponders with severe or mild ED. A receiver operating characteristic (ROC) analysis of CIMT was performed for discrimination between nonresponders and responders with moderate/mild-moderate ED. The area under the ROC curve was 0.801 (0.682-0.921) (P = .001), and the cutoff value was determined to be 0.825 mm, at which CIMT predicted the response to treatment with 65% sensitivity and 89% specificity.Clinical Implications Using a validated CIMT cutoff value can help the physician inform the patient about the possibility of drug failure and avoid attempting second-line therapy too soon.Strengths and Limitations There are three main limitations to our study. First, the number of participants was low. Second, ultrasound is a relatively subjective method, and third, all measurements were made by the same radiologist.Conclusion CIMT can be used as a predictor of response to PDE5-I therapies in patients with moderate/mild-moderate ED.