Predictors of Phosphodiesterase Type 5 Inhibitor (PDE5I) Treatment Failure in Patients Diagnosed with Erectile Dysfunction

Abstract

To determine the predictors of phosphodiesterase type 5 inhibitor (PDE5I) treatment failure in patients suffering from erectile dysfunction in order to optimize their treatment and improve compliance, and thus patient outcomes. Data for this retrospective study was obtained by reviewing the hospital records of patients with erectile dysfunction in whom PDE5I treatment failed as well as those in whom it was successful. After obtaining demographic information (age, marriage duration, BMI, smoking status, and comorbidities) related to all such cases laboratory test results (HbA1c, Total Testosterone, Free Testosterone, SHBG, Estradiol, FSH, LH, Prolactin, Vitamin D, Cholesterol, LDL, HDL, Triglyceride, PSA, TSH, T4, and CBC values) at the first visit were recorded for inclusion in analyses. Subsequent analyses focused on comparing the group of patients in whom PDE5I failed (n = 288)—denoted as treatment group—with the age-matched control group (n = 225) in whom PDE5I was successful. Analyses of all gathered data revealed statistically significant differences in HbA1c (p < .0001), free testosterone (p < .0001), and SHBG (p < .002) values between the treatment and the control group. Phosphodiesterase type 5 inhibitor (PDE5I) failure is more likely to occur in diabetic patients with high levels of HbA1c, low free testosterone and high SHBG. Thus, management of these conditions could improve treatment outcomes in this patent cohort.