Likelihood of tadalafil-associated adverse events in integrated multiclinical trial database: classification tree analysis in men with erectile dysfunction.

Objectives: To identify the patient demographic factors, comorbidities, and concomitant medications associated with a change in the likelihood of tadalafil-associated adverse events (AEs) in men with erectile dysfunction.

Methods: Pooled safety data were analyzed from 3488 tadalafil-treated men who participated in 21 placebo-controlled clinical trials of tadalafil taken as needed or once daily. Three categories of tadalafil-associated AEs were defined: vasodilatory (headache, flushing, nasal congestion, nasopharyngitis, and dizziness); musculoskeletal (back pain and myalgia); and gastrointestinal (dyspepsia). A classification and regression tree analysis was used to determine the patient characteristics most likely to be associated with a change in the likelihood of these types of AEs.

Results: Of the 3488 tadalafil-treated patients, 973 (27.9%) had any vasodilatory, musculoskeletal, and/or gastrointestinal tadalafil-associated AE. The patient characteristics associated with a change in the likelihood of any tadalafil-associated AE were diabetes, geographic region, and age. The patient characteristics associated with a change in the likelihood of a vasodilatory tadalafil-associated AE included antihypertensive medication use, geographic region, and height, with several additional splits occurring along these primary and secondary nodes. No patient characteristics associated with a change in the likelihood of musculoskeletal or gastrointestinal AEs were identified owing to the limitation of a relatively low incidence of these types of AEs.

Conclusions: The findings from classification and regression tree analyses could help physicians to better understand some of the associations between patient characteristics and the tolerability of phosphodiesterase type 5 inhibitors and could contribute to improved patient outcomes, satisfaction, treatment seeking, and treatment persistence.