Prevalence of and risk factors for erectile dysfunction in young nondiabetic obese men: results from a regional study

Oxidative Stress and Erectile Dysfunction: Pathophysiology, Impacts, and Potential Treatments

Erectile dysfunction (ED) is a prevalent condition affecting men's sexual health, with oxidative stress (OS) having recently been identified as a significant contributing causative factor. This narrative review aims to elucidate the role of OS in the pathophysiology of ED, focusing on impact, mechanisms, and potential therapeutic interventions. Key findings indicate that OS disrupts endothelial function and nitric oxide (NO) signaling, crucial for erectile function. Various sources of reactive oxygen species (ROS) and their detrimental effects on penile tissue are discussed, including aging, diabetes mellitus, hypertension, hyperlipidemia, smoking, obesity, alcohol consumption, psychological stress, hyperhomocysteinemia, chronic kidney disease, and sickle cell disease. Major sources of ROS, such as NADPH oxidase, xanthine oxidase, uncoupled endothelial NO synthase (eNOS), and mitochondrial electron transport, are identified. NO is scavenged by these ROS, leading to endothelial dysfunction characterized by reduced NO availability, impaired vasodilation, increased vascular tone, and inflammation. This ultimately results in ED due to decreased blood flow to penile tissue and the inability to achieve or maintain an erection. Furthermore, ROS impact the transmission of nitrergic neurotransmitters by causing the death of nitrergic neurons and reducing the signaling of neuronal NO synthase (nNOS), exacerbating ED. Therapeutic approaches targeting OS, including antioxidants and lifestyle modifications, show promise in ameliorating ED symptoms. The review underscores the need for further research to develop effective treatments, emphasizing the interplay between OS and vascular health in ED. Integrating pharmacological and non-pharmacological strategies could enhance clinical outcomes for ED patients, advocating for OS management in ED treatment protocols to improve patient quality of life.

Prescribing semaglutide for weight loss in non-diabetic, obese patients is associated with an increased risk of erectile dysfunction: a TriNetX database study

Semaglutide was approved in June 2021 for weight loss in non-diabetic, obese patients. While package inserts include sexual dysfunction as a side effect, no study has assessed the degree of this risk. The objective of our study is to assess the risk of developing erectile dysfunction after semaglutide is prescribed for weight loss in obese, non-diabetic men. The TriNetX Research database was used to identify men without a diagnosis of diabetes ages 18 to 50 with BMI > 30 who were prescribed semaglutide after June 1st, 2021. Men were excluded if they had a prior erectile dysfunction diagnosis, any phosphodiesterase-5 inhibitors prescription, intracavernosal injections, penile prosthesis placement, history of testosterone deficiency, testosterone prescription, pelvic radiation, radical prostatectomy, pulmonary hypertension, or were deceased. We further restricted our cohort to non-diabetic, obese men by excluding men with a prior diabetes mellitus diagnosis, a hemoglobin A1c > 6.5%, or having ever received insulin or metformin. Men were then stratified into cohorts of those that did and did not receive a semaglutide prescription. The primary outcome was the risk of new ED diagnosis and/or new prescription of phosphodiesterase type 5 inhibitors at least one month after prescription of semaglutide. The secondary outcome was risk of testosterone deficiency diagnosis. Risk was reported using risk ratios with 95% confidence intervals (95% CI). 3,094 non-diabetic, obese men ages 18-50 who received a prescription of semaglutide were identified and subsequently matched to an equal number cohort of non-diabetic, obese men who never received a prescription of semaglutide. After matching, average age at index prescription for non-diabetic, obese men was 37.8 ± 7.8 and average BMI at index prescription was 38.6 ± 5.6. Non-diabetic men prescribed semaglutide were significantly more likely to develop erectile dysfunction and/or were prescribed phosphodiesterase type 5 inhibitors (1.47% vs 0.32%; RR: 4.5; 95% CI [2.3, 9.0]) and testosterone deficiency (1.53% vs 0.80%; RR: 1.9; 95% CI [1.2, 3.1]) when compared to the control cohort of non-diabetic men who never received a semaglutide prescription.

Association between atherogenic indexes and erectile dysfunction: a cross-sectional analysis of the National Health and Nutrition Examination Survey 2001-2004

PURPOSE

Elevated blood lipids are considered a risk factor for atherosclerosis, which can lead to erectile dysfunction. This study aimed to explore the relationship between the atherogenic index of plasma (AIP), atherogenic coefficient (AC), Castelli's risk index-I (CRI-I), Castelli's risk index-II (CRI-II), and erectile dysfunction.

METHODS

Based on the National Health and Nutrition Examination Survey (NHANES) data from 2001-2004, multivariable-adjusted logistic regression models were used to evaluate the association between AIP, AC, CRI-I, and CRI-II with ED. Smooth curve fitting was employed to assess the linear association.

RESULTS

A total of 1806 male participants with complete data were enrolled in the study. In Model 1, those in the highest tertile of AIP had a 49% increased risk of ED compared to the lowest tertile (OR 1.49; 95% CI 1.15-1.91 p = 0.0021). After adjusting for the variables of age, race, education, body mass index, and poverty income ratio (PIR), significant positive correlations were found between ED and AIP, with each 1-unit increase in AIP associated with a 65% increase in the risk of developing ED (OR 1.65; 95% CI 1.03-2.64 p = 0.0361).

CONCLUSIONS

AIP is positively associated with the development of ED in US adults. More prospective cohort studies are needed to confirm the link between AIP and ED.

Muscle Strength and Male Sexual Function

Sexual dysfunction, in particular erectile dysfunction, is a common complaint among aging men. Obesity, diabetes, hypertension, and smoking are shown to be independent risk factors for erectile dysfunction, while cardiorespiratory fitness is shown to be protective. Less is known about the role of muscle strength in male sexual function. Our objective was to study the association between male sexual function and typical cardiovascular risk factors, together with exercise and muscle strength. We included data from the fourth wave of the RHINE study. Data on anthropometrics, exercise habits, diseases, muscle strength, and sexual function were collected using questionnaires, including the Aging Males' Symptoms (AMS) scale. We used multivariable logistic regression analysis to measure the association between sexual function and body mass index (BMI), age, smoking, diabetes, hypertension, exercise and muscle strength status. We included 2116 men aged 48-75 from four Nordic-Baltic countries. BMI, age, smoking, diabetes, and hypertension were found to be associated with higher odds of reporting decreased sexual function, while reporting intact muscle strength was associated with lower odds. In a large Nordic-Baltic male study population, we show that known cardiovascular risk factors are associated with decreased sexual function, while reporting intact muscle strength is associated with lower odds of reporting decreased sexual function.

Association between MTHFR c.677C>T variant and erectile dysfunction among males attending fertility clinic

Genetic risk factors have been shown to contribute to the development of sexual dysfunction. However, the role of methylenetetrahydrofolate reductase ( MTHFR ) gene variants in the risk of erectile dysfunction (ED) remains unclear. In this study, we recruited 1254 participants who underwent ED assessed by the International Index of Erectile Function-5. The MTHFR c.677C>T variant was also measured by fluorescence polymerase chain reaction (PCR). No significant difference in the genotypic frequency of the MTHFR C677T polymorphism (CC, CT, and TT) was observed between men from the ED and non-ED groups. In addition, on binary logistic regression analysis, both crude and adjusted models showed that the risk of ED was not significantly associated with the C677T polymorphism. Interestingly, a significantly higher frequency of the 677TT polymorphism was found in severe and moderate ED (P = 0.02). The positive correlation between the MTHFR 677TT polymorphism and severe ED was confirmed by logistic regression analysis, even after adjusting for potential confounders (odds ratio [OR] = 2.46, 95% confidence interval [CI] 1.15-5.50, P = 0.02). These findings suggest a positive correlation between the MTHFR 677TT polymorphism and the risk of severe ED. Identification of MTHFR gene polymorphisms may provide complementary information for ED patients during routine clinical diagnosis.

Impact of body composition analysis on male sexual function: A metabolic age study

Introduction

Metabolic Age (MetAge) and body composition analysis may reflect an individual's metabolic status, which is believed to influence male sexual and gonadal functions. Although erectile dysfunction (ED) and hypogonadism are increasingly prevalent with age, they are also detected among younger men. This study aims to assess the impact of MetAge and body composition on male sexual and gonadal status overall, and particularly in men younger than 40 years of age.

Methods

This was a cross-sectional study of 90 male healthcare workers, between the ages of 18-55, randomly selected based on their corporation numbers. In addition to Bioelectric Impedance Analysis, subjects were requested to fill the International Index of Erectile Function questionnaire (IIEF-5) and to provide an early morning serum testosterone (T) sample.

Results

The mean participants' age was 39.4 ± 9.4 years, MetAge was 45.54 ± 10.35 years, serum T level was 13.68 ± 4.49 nmol/L and BMI was 28.8 ± 4.7 kg/m2. Significant negative correlations were obtained between serum T, MetAge, body weight and fat composition. Significant negative correlations between the IIEF-5 score, MetAge, and fat composition, were only reported in subjects <40 years of age. Significantly lower T levels (p=0.002), significantly older MetAge (p=0.034), and higher BMI (p=0.044) and degree of obesity (p=0.042) were observed in participants <40 years with erectile dysfunction (ED) compared to their counterparts without ED.

Discussion

MetAge and body composition parameters significantly impact the androgenic state. ED in men <40 years is associated with lower T levels, older MetAge and higher BMI and degree of obesity.

Association of BMI with erectile dysfunction: A cross-sectional study of men from an andrology clinic

Abnormal body mass index (BMI) is associated with an increased risk of erectile dysfunction (ED). However, the relationship between different BMI categories and the levels of ED severity remains unclear. In the current study, 878 men from the andrology clinic in Central China were recruited. Erectile function was assessed by the International Index of Erectile Function (IIEF) scores. Questionnaires included questions about demographic characteristics (age, height, weight, educational status), lifestyle habits (drinking, smoking, sleep time), and medical history. Logistic regression was used to examine the association between ED risk and BMI. The incidence of ED was 53.1%. BMI was significantly higher in men from the ED group than in those from the non-ED group (P = 0.01). Compared with the normal weight group, obese men had a higher risk of ED (OR = 1.97, 95% CI = 1.25-3.14, P = 0.004), even after adjustment for potential confounders (OR = 1.78, 95% CI = 1.10-2.90, P = 0.02). Moreover, the positive correlation between obesity and moderate/severe ED severity was confirmed by logistic regression analysis (moderate/severe ED, OR = 2.71, 95% CI = 1.44-5.04, P = 0.002), even after adjusting for potential confounders (OR = 2.51 95% CI = 1.24-5.09, P = 0.01). Collectively, our findings indicate a positive correlation between obesity and the risk of moderate/severe ED. Clinicians could pay more attention to moderate/severe ED patients to maintain a healthy body weight to improve erectile function.

Non-Arteritic Anterior Ischemic Optic Neuropathy Associated With the Use of Phosphodiesterase Type 5 Inhibitors: A Literature Review

Phosphodiesterase type 5 (PDE5) inhibitors are frequently used for erectile dysfunction (ED) as the first line of treatment. This medication was initially developed to treat muscle spasms and pulmonary hypertension. The United States Food and Drug Administration (FDA) approved its usage for treating ED. Sildenafil, tadalafil, vardenafil, and avanafil are PDE5 inhibitors. The decrease of cyclic guanosine monophosphate (cGMP) in smooth muscle cells caused by sildenafil causes smooth muscle relaxation and penile erection. Vasodilation of the blood vessels reduces perfusion and blood flow to the optic nerve and eye. Several incidences of non-arteritic anterior ischemic optic neuropathy (NAION) have been recorded in sildenafil users, among other ocular complications. The onset of NAION is usually sudden and painless, and it is associated with any pattern of visual field loss. Possible symptoms include poor visual acuity, diminished color vision, a visual field defect, or hemorrhages in the form of flames. Nevertheless, NAION pathogenesis is still a mystery. Most visual effects are reversible weeks after the medication is stopped, and NAION does not seem to cause a permanent blindness. A small cup-to-disc ratio (disc at risk) and underlying systemic illnesses, such as hypertension, increase the risk of developing NAION. An early indicator of cardiovascular disease is ED. NAION diagnosis is challenging due to a lack of confirmatory diagnostic evidences. Normal visual acuity does not exclude NAION from being a possibility. In order to evaluate visual outcomes in NAION, data on both visual acuity (VA) and the full peripheral visual field are needed. Treatment with steroids did not seem to improve visual results.

Role of shear wave elastography (SWE) in erectile dysfunction patients for evaluation of daily tadalafil treatment outcome

The purpose of this study was to evaluate and anticipate the outcome of daily use of tadalafil in patients with erectile dysfunction using elastography. 183 volunteers and 183 patients with erectile dysfunction were included. Pretreatment SWE readings for our patients were calculated with a linear probe. IIEF score Q was measured once at the start of the study for volunteers and twice for patients, one prior to the start of tadalafil administration and the other on one year of 5 mg daily tadalafil after the second post-washout (one month post-treatment stopped). There was no significant difference between patients and volunteers in mean age or risk factors except in SWE values as mean SWE of volunteers was 14.03 ± 1.54 kpasc, while mean SWE of patients was 21.278 ± 8.228 kpasc. The presence of comorbid diabetes, severe disease and pre-SWE ≥23.635 was significantly associated with poor outcome. We conclude that penile SWE could be useful to select probable good responders for a continuous tadalafil use, thus avoiding the unnecessary cost and time in non-responders.

Effect of muscle distribution on lung function in young adults

BACKGROUND

At present, available research on the relationship between muscle distribution and respiratory function in healthy people is limited.

OBJECTIVE

To study the relationship between muscle distribution and lung function in healthy young adults.

METHODS

A total of 612 male and 1561 Female Chinese college students were recruited. visceral fat tissue (VAT), subcutaneous fat tissue (SAT), total body muscle mass (TMM), trunk muscle mass (TKMM), upper limb muscle mass (ULMM) and lower limb muscle mass (LLMM) was measured by body composition. Vital capacity (VC) was measured by spirometry instrument. Obesity classification was defined by muscle mass ratio (MMR), body mass index (BMI), body fat percentage (BFP), waist-to-hip ratio (WHR).

RESULTS

Among these positive correlation parameters, male VC had a high positive correlation with TMM and LLMM, while female VC had a high positive correlation with TMM and TKMM. After the population was divided into MMR, BMI, BFP, and WHR, further analysis showed that VC was positively correlated with TMM for males with MMR-low muscle (r = 0.483; p < 0.05), BMI-underweight (r = 0.265; p < 0.05), BMI-overweight + obesity (r = 0.272; p < 0.05), BFP-low fat (r = 0.306; p < 0.05), and WHR-normal subgroups (r = 0.316; p < 0.05), while LLMM was positively correlated with VC in the MMR-normal muscle (r = 0.285; p < 0.05), BMI-normal (r = 0.305; p < 0.05), BFP-normal fat (r = 0.304; p < 0.05), and WHR obesity subgroups (r = 0.266; p < 0.05). VC was positively correlated with TMM for females with MMR-low muscle (r = 0.169; p < 0.05), MMR-normal muscle (r = 0.241; p < 0.05), BMI-underweight (r = 0.241; p < 0.05), BMI-normal (r = 0.288; p < 0.05), WHR normal (r = 0.275; p < 0.05), and BFP-low fat subgroups (r = 0.255; p < 0.05), while TKMM was positively correlated with VC in the BMI-overweight + obesity (r = 0.342; p < 0.05), WHR-obesity (r = 0.227; p < 0.05), and BFP-normal subgroups (r = 0.256; p < 0.05).

CONCLUSIONS

Muscle distribution in young adults is highly correlated with VC, and this relationship is affected by gender and body types. In general, for thin, VC is more positively correlated with TMM, and for normal weight or obese, VC is more positively correlated with LLMM for males but with TKMM for females, respectively, in comparison with other tested indices. Further studies will be required to evaluate the relationship between muscle distribution and vital capacity in young adults.

The association between acquired premature ejaculation and metabolic syndrome in young Chinese men

We conducted the study to investigate the association between metabolic syndrome (MetS) and acquired premature ejaculation (APE). From January 2017 to December 2019, 1,000 subjects, 500 men with APE (APE group) and 500 men without APE (control group), were selected. Self-estimated intravaginal ejaculatory latency time (IELT) and Premature Ejaculation Diagnostic Tool (PEDT) were recorded from each participant to evaluate APE. Detailed physical examinations, body composition analysis and blood tests were all assessed. The neck circumference, waist circumference, visceral fat rating, fat mass, fasting blood glucose (FBG) and highly sensitive C-reactive protein (hs-CRP) in the APE group were significantly higher than the control group (p < .05 for all). Furthermore, the APE population had a higher prevalence of MetS than the control group (49.4% versus 35.6%, p = .000). Consistent results could also be observed in terms of the number of MetS components and each component of the MetS (both p < .05). Moreover, both the prevalence of APE and the severity of PE increased significantly as the number of MetS components increased. Finally, in the multivariate analysis, we found that both MetS and hs-CRP were independent risk factors for APE (both p < .01). The results indicated that APE was related to MetS but not its components.