Do patients’ baseline characteristics with erectile dysfunction, predict phosphodiesterase type 5 (PDE5) inhibitors’ efficacy and patients’ preference? A comparative, randomized, open-label, crossover study.

The patients were treated with the three known phosphodiesterase type 5 (PDE 5) inhibitors (sildenafil 100mg, vardenafil 20mg and tadalafil 20mg) which were administered with incidental sequence. A week wash out period was followed after each of the three treatment period.All of them completed the International Index of Erectile Function 15 (IIEF-15) questionnaire following by a detailed medical and psychological history. Baseline variables examined were age, body mass index, alcohol consumption, smoking status, physical activity, Erectile dysfunction (ED) aetiology/duration, comorbidities in medical history, medication intake, psychological status and baseline scores for the IIEF domains. The maximum dose was used for at least 4 attempts for intercourse with each one of them (4 pills from each drug) during a 4-weeks period. The attempt for intercourse must be start at least 30 minutes after the oraly intake of the medication (single dose) and not earlier. If the patient wanted to try second intercourse within 24 hours, he would have tried with the same pill. He might take second one only after at least 24 hours. No other instructions were given (about food intake or drink consumption). In every follow up visit, the Sexual encounter Profile (SEP) diary were selected and the IIEF questionnaire was completed. The study for statistically reasons divided in four arms. The first arm included the first visit of the patient to the doctor (before medication). The second arm included the results after sildenafil 100mg intake. The third and the fourth after vardenafil 20mg and tadalafil 20mg respectively.