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.