Antioxidant treatment for oligoasthenoteratozoospermia and varicocele: a DBPC trial to evaluate the impact of age and body mass index

Abstract

Oxidative stress is one of the main mechanisms responsible for male infertility. Various conditions such as varicocele, obesity, advanced age, and lifestyle can lead to an increase in reactive oxygen species, causing an oxidative imbalance in the reproductive environment. Spermatozoa are sensitive to reactive oxygen species and require energy to carry out their main function of fertilizing the egg. Excessive reactive oxygen species can affect sperm metabolism, leading to immobility, impaired acrosome reaction, and cell death, thereby impairing reproductive success. This double-blind randomized study evaluated the effect of supplementation with L-carnitine, acetyl-L-carnitine, vitamins, and other nutrients on semen quality in 104 infertile patients with or without varicocele, while also investigating the impact of factors such as obesity and advanced age on treatment. Sperm concentration significantly increased in the supplemented group compared to the placebo group ( P = 0.0186). Total sperm count also significantly increased in the supplemented group ( P = 0.0117), as did sperm motility ( P = 0.0120). The treatment had a positive effect on patients up to 35 years of age in terms of sperm concentration ( P = 0.0352), while a body mass index (BMI) above 25 kg m -2 had a negative effect on sperm concentration ( P = 0.0110). Results were not showing a net benefit in stratifying patients in accordance with their BMI since sperm quality increase was not affected by this parameter. In conclusion, antioxidant supplementation may be beneficial for infertile patients and has a more positive effect on younger patients with a normal weight.

Figure 1

The study is designed as a double-blind controlled trial with 104 infertile patients, divided by the presence of varicocele. The volunteers received a supplementation with antioxidants and metabolites or placebo for a period of 6 months. Before the treatment, a semen analysis was conducted in each patient, and after 6 months another semen analysis was conducted. At the end of the study, 94 patients completed.

Figure 2

Forest plot summarizing the effect of antioxidant treatment in accordance with presence of varicocele, different age, different BMI and group of treatment. Each seminal parameter has been evaluated (sperm count, concentration, motility and morphology). CI: confidence interval; OR: odds ratio; BMI: body mass index.

Figure 3

Representation of decision curve analysis, considering the BMI factor on the values of sperm concentration and motility in varicocele group. BMI: body mass index.