Phosphorus as predictive factor for erectile dysfunction in middle aged men: A cross sectional study in Korea

Abstract

PurposeHigh serum inorganic phosphorus level is related with atherosclerosis and an elevated risk of cardiovascular disease. At the same time, the association of phosphorus with erectile dysfunction (ED) is not well reported. We studied the effect of serum phosphorus on ED and the relationship with other clinical variables.Materials and MethodsFrom March to September 2013, 1,899 police men aged 40 to 59 years who entered in a prostate health screening were targeted. All subjects underwent a clinical checking using the International Index of Erectile Function-5 (IIEF-5) questionnaire translated into Korean. Serum prostate-specific antigen (PSA), testosterone, inorganic phosphorus, body mass index, metabolic syndrome (MetS), and prostate ultrasound were also examined.ResultsSerum inorganic phosphorus (r=–0.108, p<0.001) had the highest correlation coefficient with IIEF-5 score other than age, followed by prostate volume (PV) (r=–0.065, P<0.001). Using logistic regression analysis, age, phosphorus, and MetS were predictive factors for moderate to severe ED in univariate analysis. PSA, testosterone, body mass index, and PV could not predict ED. Age, MetS, and phosphorus were independent predictive factors of moderate to severe ED (p<0.001; odds ratio [OR], 1.119; 95% confidence interval [CI] 1.086–1.153; p=0.048; OR, 1.283; 95% CI, 1.003–1.641; and p=0.048; OR, 1.101; 95% CI, 1.076–1.131) in the multivariate analysis.ConclusionsIn our study, phosphorus level is related with ED. Phosphorus is a significant predictor of ED and a strong factor that can be modified in the middle-age. Controlling phosphorus in men may have a particular meaning of preventing the occurrence of ED.

A High Phosphorus Diet Impairs Testicular Function and Spermatogenesis in Male Mice with Chronic Kidney Disease

“…A high serum phosphate concentration is a common complication in the progress of CKD. Both CKD and hyperphosphatemia have adverse effects on fertility [12,13]. Therefore, this study hypothesized that phosphate would aggregate CKD-induced negative reproductive outcomes, in turn confirming the importance of phosphate restriction in CKD to achieve a better male fertility and life quality.…”

“…Several studies have shown that a high serum phosphate level contributes to cardiac calcification, bone diseases, and the risk of death in CKD patients [9][10][11]. In addition, the phosphorus level was found to be positively correlated with the severity of erectile dysfunction, the inability to get or maintain an erection [12]. Low testosterone production and abnormal sperm function in CKD [13,14] or excess phosphorus [15,16] have also been observed.…”

Letter to the editor: Phosphorus as predictive factor for erectile dysfunction in middle aged men: A cross sectional study in Korea; Methodological issues to avoid prediction fallacy

“…We read the paper written by Min et al [ 1 ] and published in Investigative and Clinical Urology in 2016. The authors aimed to study the effect of serum phosphorus on erectile dysfunction (ED) and the relationship with other clinical variables.…”

“…First, Min et al [ 1 ] evaluated the predictive performance of serum phosphorus on ED in a cross-sectional study, whereas longitudinal studies are most important for making assumptions for clinical prediction models [ 2 ]. In other words, the temporality assumption (the dependent variable has to occur after the independent variable) must be ensured in the prediction model.…”

“…Otherwise, the analogous nonparametric test, i.e., the Kruskal-Wallis test, must be applied. In the study by Min et al [ 1 ], all of the variables are considered to be normally distributed because no evaluation was done on the distribution of variables.…”