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Serum l-carnitine and vitamin D levels may be low among oral sildenafil citrate non-responders

International Journal of Impotence Research volume 31, pages 85–91 (2019)Cite this article

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Abstract

This cross-sectional comparative study aimed to compare serum l-carnitine and 25(OH)D levels between men with ED non-responding for oral sildenafil citrate and healthy volunteers. Overall, 192 men, recruited from two University Hospitals, were allocated into two equal groups of matched age; healthy potent men and men with ED non-responders for oral sildenafil citrate. Oral sildenafil citrate non-responders self-reported inadequate erectile responses after four attempts using 100 mg with the manufacturer’s guidelines relative to meals, associated medications, and sexual stimulation/arousal. Exclusion criteria were: diabetes, cardiovascular disorders, beta blockers treatment, morbid obesity, thyroid disorders, post-radical prostatectomy, and hepatic/renal failure. All participants were subjected to; history taking, clinical examination, validated IIEF-5 questionnaire, estimation of serum l-carnitine by calorimetric method and serum 25(OH)D by ELISA method. Compared with potent controls, ED men non-responders for oral sildenafil citrate showed significant decreases in the mean serum l-carnitine level (16.8 ± 3.6 uM/L versus 66.3 ± 11.9 uM/L, P = 0.001), the mean serum 25(OH)D level (21.2 ± 7.1 ng/ml versus 54.6 ± 7.9 ng/mL, P = 0.001) and IIEF-5 score (7.8 ± 2.6 versus 23.9 ± 1.3). Serum l-carnitine showed significant positive correlation with IIEF-5 scores (r = 0.873, P = 001), serum 25(OH)D (r = 0.796, P = 0.001) and significant negative correlation with the age (r = -0.515, P = 0.001). Serum 25(OH)D showed significant positive correlation with IIEF-5 scores (r = 0.855, P = 0.001) and significant negative correlation with the age (r = -0.223, P = 0.005). It is concluded that normal homeostasis of serum l-carnitine and 25(OH)D play a role in male sexual health being significantly decreased in ED non-responding for oral sildenafil citrate.

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Authors and Affiliations

  1. Department of Andrology, Sexology & STIs, Faculty of Medicine, Cairo University, Cairo, Egypt

    Taymour Mostafa

  2. Department of Medical Biochemistry, Faculty of Medicine, Cairo University, Cairo, Egypt

    Laila A. Rashed

  3. Department of Medical Biochemistry, Faculty of Medicine, Cairo University, Cairo, Egypt

    Dina A. Sabry

  4. Department of Andrology, Sexology & STIs, Faculty of Medicine, Cairo University, Cairo, Egypt

    Ihab Osman

  5. Department of Andrology, Sexology & STIs, Faculty of Medicine, Beni-Suef University, Beni-Suef, Egypt

    Nashaat Nabil

  6. Faculty of Medicine, The Qar University, Nasiriya, Iraq

    Firas Kareem

  7. Department of Dermatology& Andrology, Egyptian Railway Hospital, Cairo, Egypt

    Ingi A. Mostafa

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Mostafa, T., Rashed, L.A., Sabry, D.A. et al. Serum l-carnitine and vitamin D levels may be low among oral sildenafil citrate non-responders. Int J Impot Res 31, 85–91 (2019). https://doi.org/10.1038/s41443-018-0036-4

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