{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T17:13:14Z","timestamp":1767978794602,"version":"3.49.0"},"reference-count":37,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,5,26]],"date-time":"2021-05-26T00:00:00Z","timestamp":1621987200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Erectile dysfunction (ED) is a frequent sexual disorder in adult men. Klinefelter syndrome (KS) is the most common sex chromosomal disorder and a frequent cause of male hypogonadism. Psychological and cognitive aspects are quite typical in KS and have been linked to ED, while the role of testosterone (T) levels in sexual function of KS subjects has not been fully elucidated. The purpose of the present study is to investigate the role of hormonal disturbances in erectile function of subjects with KS. We conducted a retrospective study involving 52 Klinefelter patients newly diagnosed who never received androgen replacing therapy. All the subjects underwent medical history, accurate physical examination, and blood tests. The International Index of Erectile Function questionnaire (IIEF-EF) score correlated negatively with estradiol\/testosterone ratio (E2\/T); this correlation remained statistically significant after correction for age (\u03c1 \u22120.320 p = 0.018). A multiple linear regression analysis identified age and E2\/T as the main predictors of IIEF-EF score (R2 0.169 F = 3.848 p = 0.008). Our findings corroborate previous KS data obtained in the general population showing an association between higher E2\/T ratio and impaired erectile function. Larger studies are required to better elucidate the pathophysiology of ED in patients with KS.<\/jats:p>","DOI":"10.3390\/jcm10112319","type":"journal-article","created":{"date-parts":[[2021,5,26]],"date-time":"2021-05-26T10:30:32Z","timestamp":1622025032000},"page":"2319","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Estradiol\u2013Testosterone Imbalance Is Associated with Erectile Dysfunction in Patients with Klinefelter Syndrome"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0821-3591","authenticated-orcid":false,"given":"Maurizio","family":"De Rocco Ponce","sequence":"first","affiliation":[{"name":"Andrology Department, Fundaci\u00f3 Puigvert, Instituto de Investigaciones Biom\u00e9dicas Sant Pau (IIB-Sant Pau), Departamento de Medicina, Universitat Aut\u00f3noma de Barcelona, 08041 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Riccardo","family":"Selice","sequence":"additional","affiliation":[{"name":"Unit of Andrology and Reproductive Medicine, Department of Medicine, University of Padova, Via Giustiniani 2, 35128 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonella","family":"Di Mambro","sequence":"additional","affiliation":[{"name":"Unit of Andrology and Reproductive Medicine, Department of Medicine, University of Padova, Via Giustiniani 2, 35128 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Luca","family":"De Toni","sequence":"additional","affiliation":[{"name":"Unit of Andrology and Reproductive Medicine, Department of Medicine, University of Padova, Via Giustiniani 2, 35128 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6576-2183","authenticated-orcid":false,"given":"Carlo","family":"Foresta","sequence":"additional","affiliation":[{"name":"Unit of Andrology and Reproductive Medicine, Department of Medicine, University of Padova, Via Giustiniani 2, 35128 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4736-9051","authenticated-orcid":false,"given":"Andrea","family":"Garolla","sequence":"additional","affiliation":[{"name":"Unit of Andrology and Reproductive Medicine, Department of Medicine, University of Padova, Via Giustiniani 2, 35128 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1598","DOI":"10.1111\/j.1743-6109.2010.01778.x","article-title":"Definitions\/epidemiology\/risk factors for sexual dysfunction","volume":"7","author":"Lewis","year":"2010","journal-title":"J. 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