Low Serum 25-Hydroxyvitamin D Level as a Potential Risk Factor of Erectile Dysfunction in Elderly Men with Moderate to Severe Lower Urinary Tract Symptoms

Severity of erectile dysfunction and premature ejaculation positively correlate with aggression levels in men: insights from a large population-representative study

The effects of erectile dysfunction (ED) and premature ejaculation (PE) on men's mental health are well-studied, but their link to aggression has been less explored. Thus, we measured associations between ED, PE, and aggression of men in a large representative cohort with well-balanced demographic characteristics. Participants completed computer-assisted web interviews with reliable questionnaires to assess ED, PE, and aggression. These included the five-item International Index of Erectile Function (IIEF-5), the Premature Ejaculation Diagnostic Tool (PEDT), and the Aggression Module of the Hospital Anxiety and Depression Scale-Modified Version (A-HADS-M). A representative sample of adult men was generated based on the most recent census data, incorporating age and place of residence as quota controls, along with sample size calculations. We interviewed 3001 men, with a mean IIEF-5 score of 18.92 ± 5.04, a mean PEDT score of 7.15 ± 4.26, and a mean A-HADS-M score of 2.71 ± 1.64. We found that aggression was more prevalent in those with ED or PE (p < 0.001). The greater the severity of ED and PE, the greater was the intensity of aggression (Spearman's rank correlation coefficients of -0.207, p < 0.001 and 0.19, p < 0.001 for ED and PE, respectively). Univariate regression models showed significant links between aggression and both ED and PE across age groups. Multivariate models confirmed that these associations were significant and independent of age, sociodemographic factors, comorbidities, and lifestyle habits (regression coefficients: -0.041, p < 0.001 for ED and 0.028, p < 0.001 for PE). Our findings convincingly demonstrated a consistent association between aggression, ED, and PE, warranting further investigation into the underlying mechanisms of these relationships.

No bidirectional association between serum 25-hydroxyvitamin D and erectile dysfunction: Mendelian randomization and genetic association studies

Background

The causal relationship between the level of serum 25-hydroxyvitamin D [25(OH)D] and the risk of erectile dysfunction (ED) is still unclear.

Aim

We tried to determine the causal relationship between the level of serum 25(OH)D and ED risk.

Methods

In this study, we used genome-wide association study data from the UK Biobank to analyse the relationship between serum 25(OH)D (as the exposure) and ED (as the outcome). Linkage disequilibrium score regression (LDSC) was used to assess the genetic correlation between 2 traits. The CAUSE (Causal Analysis using Summary Effect estimates) method and Mendelian randomization (MR) were employed to evaluate the bidirectional causal relationship. The MRlap method was utilized to assess the impact of sample overlap on the results. To assess potential heterogeneity and horizontal pleiotropy, we utilized methods such as MR-Egger, MR-PRESSO (Mendelian Randomization Pleiotropy Residual Sum and Outlier), weighted median, and others.

Outcomes

The primary outcome was defined as self or physician-reported ED, or using oral ED medication, or a history of surgery related to ED.

Results

The LDSC analysis did not reveal a significant genetic correlation between serum 25(OH)D and ED (rg = 0.2787, P = .3536). Additionally, the CAUSE (P value testing that the causal model is a better fit >.05) and MR analyses (odds ratio, 0.8951; 95% confidence interval, 0.7480-1.0710; P = .2260) did not support a causal relationship between 25(OH)D and ED, and our study did not detect any heterogeneity and pleiotropy.

Clinical implications

This study provides evidence on whether vitamin D needs to be ingested to prevent or treat ED.

Strengths and limitations

We used LDSC and MR to avoid bias. However, the population in this study was limited to European ancestry.

Conclusion

No causal relationship was found between 25(OH)D and ED.

Serum 25-hydroxyvitamin D level and erectile dysfunction: a causal relationship? Findings from a two-sample Mendelian randomization study

Background

Serum 25-hydroxyvitamin D level is associated with erectile dysfunction (ED) in observational studies. However, whether there is a causal association between them remains uncertain.

Objective

Conduct a two-sample Mendelian randomization (MR) analysis to investigate the causal effect between serum 25-hydroxyvitamin D level and ED risk.

Method

Genome-wide association study (GWAS) data of serum 25-hydroxyvitamin D levels comprising 6,896,093 single nucleotide polymorphisms (SNP) from 496,949 people of European ancestry were regarded as exposure for the MR analysis. Additional GWAS data involving 9,310,196 SNPs of 6,175 European ED cases and 217,630 controls were used as outcome data. The MR-Egger, inverse variance weighted (IVW) method, weighted median, simple mode, and weighted mode were employed to evaluate causal effects, among which IVW was the primary MR analysis method. The stability of the MR analysis results was confirmed by a heterogeneity test, a horizontal pleiotropy test, and the leave-one-out method.

Result

There were 103 SNPs utilized as instrumental variables (p < 5 × 10-8). The results of MR analysis showed no causal effects of serum 25(OH) D concentration on ED risks (IVW; OR = 0.9516, 95% CI = 0.7994 to 1.1328, p = 0.5772). There was no heterogeneity and pleiotropy in the statistical models.

Conclusion

The present MR study did not support a causal association for genetically predicted serum 25-hydroxyvitamin D concentration in the risk of ED in individuals of European descent.

Effects of Vitamin D Supplementation on Testosterone, Prostate, and Lower Urinary Tract Symptoms: A Prospective, Comparative Study

PURPOSE

Several studies have associated the serum vitamin D level with total testosterone levels and the prostate volume. Herein, we investigated the effect of vitamin D supplementation on testosterone, prostate, and lower urinary tract symptoms (LUTS) in men.

MATERIALS AND METHODS

Men over 40 years of age diagnosed with a vitamin D deficiency (25[OH]D <20 ng/mL) who received vitamin D supplementation for one year were included in the study and administered 25,000 IU of cholecalciferol every 2 weeks. Prostate ultrasound, uroflowmetry, postvoid residual urine volume measurement, and serological tests (serum testosterone levels, etc.) were performed upon diagnosis and one year later. Participants also answered the International Prostate Symptom Score (IPSS) and Aging Males' Symptoms Scale (AMS) questionnaires.

RESULTS

A significant increase was observed in the vitamin D level following one year of vitamin D supplementation, with a significant decrease in the postvoid residual urine volume, total IPSS score and without a significant change in the prostate volume. Improved psychological subscale score of AMS questionnaire was observed with a statistical significance.

CONCLUSIONS

Vitamin D supplementation suppressed the increase in the prostate volume and improved the LUTS. Although there is no direct effect on serum testosterone levels, vitamin D supplementation helped improve hypogonadal symptoms.

Mechanisms Suggesting a Relationship between Vitamin D and Erectile Dysfunction: An Overview

Vitamin D deficiency (VDD) and erectile dysfunction (ED) heavily burden the male population. The higher prevalence of both conditions in the elderly suggests a possible relationship between the two conditions. In addition, in vitro, animal, and human studies have revealed several mechanisms that may relate VDD to ED. The main mechanism by which vitamin D might exert its action on sexual function appears to be through the regulation of endothelial function. Indeed, VDD correlates with several markers of endothelial function. The action of vitamin D on the endothelium would be exercised both indirectly through its intervention in inflammatory processes and through the production of oxygen free radicals, and directly through the regulation of vascular stiffness, the production of nitric oxide, and the regulation of vessel permeability. Furthermore, the ubiquitous distribution of the vitamin D receptor in the human body means that this hormone can also exert a beneficial effect on erectile function by interfering with those comorbidities significantly associated with ED, such as hypertension, diabetes mellitus, hypercholesterolemia, chronic kidney disease, and hypogonadism. In this review, we thoroughly and carefully presented the evidence and mechanisms that would appear to relate vitamin D levels to erectile function. Furthermore, we have summarized the meta-analytic evidence for and against this association to provide a true representation of this topic. Data published to date suggest that low levels of vitamin D could contribute to worsening erectile function through several mechanisms. Therefore, vitamin D levels should be measured in patients with ED and maintained at adequate levels by specific supplementation in case of deficiency. However, the low quality and heterogeneity of clinical trials evaluating the effects of vitamin D administration on erectile function and ED-associated comorbidities do not allow for a univocal conclusion, and indicate the need for further studies to analyze these aspects.