Akademik Veri Yönetim Sistemi
Sexual Medicine, cilt.14, sa.4, 2026 (SCI-Expanded, Scopus)
Background: Non-organic ED patients have cardiac autonomic dysfunction measurable by heart rate variability (HRV). Tadalafil reduces cardiovascular mortality, but exact mechanisms remain unclear. Aim: To evaluate daily tadalafil effects on cardiac autonomic regulation in non-organic ED and identify clinical predictors of HRV response. Methods: In this prospective study, 82 men with non-organic ED (mean age 46.8 ± 5.0 years) received tadalafil 5-10 mg daily. Assessment included International Index of Erectile Function-Erectile Function (IIEF-EF), echocardiography, laboratory tests, and 24-hour Holter ECG. HRV was analyzed via time-domain (standard deviation of NN intervals [SDNN], root mean square of successive differences [RMSSD]) and frequency-domain (low-frequency power [LF], high-frequency power [HF], LF/HF ratio) parameters. Post-treatment recordings were blindly evaluated. Early response to tadalafil was defined as achievement in the severity-adjusted Minimal Clinically Important Difference (MCID) in IIEF-EF or final IIEF-EF score ≥26. Outcomes: Primary: ΔSDNN. Secondary: ΔHF power, ΔLF/HF ratio. Results: IIEF-EF improved significantly (15 to 23, P < .001) and 74.4% were early responders (n = 61). In the overall cohort, SDNN increased (42.39 to 52.39 ms, P < .01), HF power increased (267.86 to 294.44 ms2,P < .001), and LF/HF ratio decreased (2.78 to 2.31, P < .01). Both groups showed HRV improvements without between-group differences (P > .05), suggesting autonomic modulation independent of erectile response. Multivariable regression: diabetes negatively predicted SDNN improvement; higher testosterone, higher baseline IIEF-EF score, and lower BMI predicted greater HF enhancement. Only 1.1% of patients discontinued the treatment (due to dyspepsia). Clinical Implications: Daily tadalafil treatment may enhance parasympathetic modulation in men with non-organic ED regardless of clinical erectile improvement, suggesting a potential mechanism for its observed cardiovascular benefits. Strengths and Limitations: Strengths include rigorous, blinded Holter assessment. Limitations include the lack of a placebo control, short follow-up (28 days), and a small non-responder subgroup. Conclusion: Daily tadalafil enhanced parasympathetic modulation and reduced sympathovagal imbalance independently of erectile improvement.