NUTRACEUTICAL INTERVENTIONS FOR ERECTILE DYSFUNCTION: A SYSTEMATIC REVIEW AND NETWORK META-ANALYSIS

Although nutraceutical-based treatments are often provided for erectile dysfunction (ED), their efficacy remains doubtful, and the choice of one preparation over the other is challenged by the dearth of head-to-head comparative studies. We compared the efficacy of available nutraceutical interventions, alone or in combination with phosphodiesterase type 5 inhibitors (PDE5i), in improving erectile function in men with ED through a network meta-analysis (NMA), considering direct and indirect evidence into one model thus generating a hierarchy of effectiveness.

Several databases were searched for RCTs assessing the effect of any nutraceutical administration in improving erectile function when compared to each other, placebo, and/or PDE5i in men with ED. Data were included in a random-effects NMA, where medicaments effect was rated by surface under the cumulative ranking curve (SUCRA). Two NMAs were also carried out separately for organic and non-organic ED. Reciprocal comparisons between all therapy were assessed by league tables.

The main outcome was the standardized mean difference in the score of the International Index of Erectile Function IIEF-5 or IIEF-6. Fifteen RCTs yielded information on 1000 men with ED. In the overall NMA, compared to placebo, the combination propionyl L-carnitine (PLC) + acetyl L-carnitine (ALC) + Sildenafil was associated with the highest SUCRA (97%) in improving erectile function score, followed by L-Arginine + Tadalafil (84%), Sildenafil (79%), Tadalafil (72%), and L-Arginine (52%). No other treatment regimen showed efficacy with statistical significance. In organic ED, the efficacy of Sildenafil and Tadalafil was significantly improved by PLC + ALC and L-Arginine, respectively. Conversely, in non-organic ED, nutraceuticals did not improve the therapeutic performance of daily Tadalafil.

This NMA contributes valuable insights into the potential of nutraceutical interventions for ED. Against a background of general ineffectiveness of most nutraceutical interventions, L-Arginine and the mix PLC + ALC appeared to be of some usefulness in improving erectile function, especially in combination with PDE5i in organic ED.

Every author has any conflict of interest to declare.