Elevated atherogenic index is associated with a higher risk of erectile dysfunction

New research highlights the critical role of lipid profiles in men’s health, revealing that higher levels of an atherogenic marker may not only signal heart problems but also significantly increase the risk of erectile dysfunction.

Study: Association between plasma atherogenic index and erectile dysfunction in US men: a population-based cross-sectional study. Image credit: Rocos / Shutterstock

In a recent study published in International Journal of Impotence Researcha group of researchers thoroughly examined the relationship between atherogenic plasma index (AIP) (the ratio of triglycerides to HDL cholesterol, a predictor of coronary heart disease severity) and erectile dysfunction (ED) (inability to maintain an erection) using data from the National Health and Nutrition Examination Survey (NHANES).

Background

Erectile dysfunction (ED), which is the inability to achieve or maintain an erection for satisfactory sexual intercourse, affects a significant proportion of men worldwide.

Although not life-threatening, ED can significantly affect men’s physical and mental health as well as relationships. It shares common risk factors with cardiovascular disease (CVD), such as atherosclerosis (narrowing of the artery due to plaque build-up), endothelial dysfunction (reduced function of the lining of the blood vessels, which affects circulation), and inflammation, making CVD a potential biomarker for cardiovascular disease.

AIP, a measure of cardiovascular risk based on lipid profiles, is gaining attention. However, the exact mechanisms linking AIP and ED require further investigation, particularly through large-scale and diverse population studies.

Understanding this relationship is clinically important as it could lead to better risk assessment and early intervention strategies for both DM and CVD.

About the study

The study population was drawn from the NHANES database, with all participants providing informed consent. NHANES uses complex sampling designs, interviews, laboratory tests, and physical examinations to assess the health of the US population.

Data from two NHANES cycles (2001–2002 and 2003–2004) were selected for analysis because these cycles included information on ED and AIP. Exclusion criteria included participants older than 70 years (due to higher prevalence of confounding health conditions), missing data on AIP or ED, participants older than 70 years, and individuals with incomplete information on relevant variables such as poverty income index (PIR) , body mass index (BMI) and hypertension.

Participants reported their ability to achieve and maintain an erection, with responses categorized as ‘never’, ‘usually’, ‘sometimes’ or ‘almost always’. Those who answered “sometimes” or “never” were classified as having ED. AIP was calculated as log10 (triglycerides (TG)/high-density lipoprotein cholesterol (HDL-C)). Covariates included age, BMI, blood glucose, PIR, ethnicity, cholesterol levels, marital status, diabetes, hypertension, education, cardiovascular disease, alcohol consumption, hyperlipidemia (high blood fat levels), and smoking status. These covariates were grouped into categories such as demographic factors, health conditions, and lifestyle factors for a more comprehensive analysis.

Statistical analysis was performed using R software, applying sample weights to reflect the complex survey design of NHANES. Linear regression for continuous variables, chi-square test for categorical variables, and multivariate logistic regression were used to assess the relationship between AIP and ED.

A comprehensive set of sensitivity analyzes was performed to confirm the robustness of the findings, particularly by applying a stricter definition of ED (patients who “never” achieved a satisfactory erection). This approach ensured that the observed relationships between AIP and ED were not due to methodological inconsistencies. Statistical significance was set at P < 0.05.

Study results

In the study, AIP was significantly higher in participants with DM (0.21 ± 0.02) compared to those without DM (0.08 ± 0.01), showing a strong statistical difference (P < 0.0001). In addition, DM subjects tended to have higher levels of age, BMI, fasting blood glucose (FBG), TG, alcohol use, diabetes, CVD, smoking, and hypertension, while HDL-C, education, and PIR levels were lower. . A higher proportion of DM patients were also married or living with a partner.

The study revealed a statistically significant higher AIP in participants with DM, indicating its potential as a biomarker for predicting DM risk. The association between AIP and ED was rigorously analyzed, with results showing that AIP, treated as a continuous variable, was positively associated with ED.

This association remained statistically significant after adjustment for various factors such as age, race, education, and marital status and after further adjustments for additional covariates. When AIP was divided into tertiles, a progressive increase in the odds of DM was observed in all tertiles, further confirming the association between higher levels of AIP and increased risk of DM.

Sensitivity analyzes further strengthened these findings, demonstrating that the association between AIP and ED was not only statistically significant but also consistent even when using stricter criteria to define ED. A generalized additive model and smooth curve fitting further demonstrated a positive, linear relationship between AIP and ED.

Subgroup analyzes revealed that DM risk was particularly pronounced among those older than 50 years, non-Hispanic whites, those with CVD, and those with a lower or moderate BMI.

These findings highlight the importance of considering population-specific characteristics when assessing AIP-related DM risk. No significant interactions were detected in the subgroups analyzed.

In sensitivity analyzes using a stricter definition of ED (patients who “never” achieved a satisfactory erection), the association between BP and ED remained strong, confirming the robustness of the original findings. The linear positive relationship between AIP and severe ED persisted in these analyses.

Susceptibility subgroup analysis also showed stronger associations in older individuals, moderate BMI, and patients with hypertension or diabetes, further underscoring the relationship between AIP and DM, particularly in specific populations. When AIP was divided into tertiles, a progressive increase in the odds of DM was observed in all tertiles, further confirming the association between higher levels of AIP and increased risk of DM.

conclusions

In summary, this study not only identified a significant association between higher AIP levels and increased DM risk among US men, but also demonstrated the reliability of these findings through rigorous sensitivity analyzes and detailed subgroup assessments. Even after adjusting for potential confounders, the association between increased AIP and ED remained strong.

These findings are in line with a similar study conducted at the same time, further supporting the reproducibility of the results. Sensitivity analyzes strengthened the relationship, and the study also found a higher prevalence of CVD among DM patients. This suggests that atherogenic dyslipidemia, indicated by elevated AIP, may play a role in the development of DM.

The implications for clinical practice are significant. Early assessment of AIP could be crucial to identify individuals at increased risk for DM, particularly in specific subpopulations such as those with cardiovascular disease or metabolic disorders.

Future research should focus on elucidating the causal mechanisms underlying this relationship and exploring the potential for targeted interventions to moderate the risk of DM in individuals with high AIP.