Abstract
Erectile dysfunction (ED) is a common male health condition and is increasingly recognised as an early marker of systemic vascular dysfunction. The Endothelial Activation and Stress Index (EASIX), calculated from lactate dehydrogenase, creatinine, and platelet count, reflects endothelial injury and microvascular stress, yet its relationship with ED has not been well characterised in population-based studies. Using data from the National Health and Nutrition Examination Survey (NHANES) 2001-2004, this cross-sectional analysis included 3,540 adult men with available laboratory and questionnaire data. Survey-weighted multivariable logistic regression models were employed to evaluate the association between EASIX and ED, with additional subgroup and interaction analyses performed to examine potential effect modification. Overall, 999 participants (28.22%) reported ED. Higher EASIX levels were independently associated with greater odds of ED across progressively adjusted models. In the fully adjusted model, each one-unit increase in log2-transformed EASIX was associated with a 31% higher likelihood of ED (odds ratio [OR] = 1.31, 95% confidence interval [CI] = [1.07, 1.61]). Significant interactions were observed by age, race, poverty-income ratio (PIR), and hypertension status. Positive associations were particularly evident among men older than 50 years, non-Hispanic White individuals, those with higher socioeconomic status (PIR >3.5), and participants with hypertension. These findings suggest that elevated EASIX is independently associated with ED in U.S. adult men and that this association varies across key demographic and clinical subgroups, highlighting the potential relevance of endothelial dysfunction in male sexual health.