Longitudinal associations between changes in body mass index and erectile dysfunction

BACKGROUND: Erectile dysfunction (ED) is a multifactorial condition and an early indicator of systemic vascular dysfunction. Although obesity is a major modifiable risk factor for ED, the longitudinal impact of body mass index (BMI) trajectories remains poorly understood, particularly in populations outside North America and Europe. AIM: We aimed to examine the longitudinal association between BMI trajectory patterns and erectile dysfunction among Brazilian men. METHODS: This longitudinal cohort study included 924 Brazilian men aged ≥40 years with ED at baseline who underwent routine health evaluations between 2008 and 2022. BMI, ED (assessed with the IIEF-5), and demographic, clinical, and lifestyle factors were measured at baseline and follow-up visits (300-800 days apart). Participants were categorized into four BMI trajectories: remained healthy, became healthy, became obese, or remained obese. Associations with ED were analyzed using hierarchical logistic regression adjusted for demographic, clinical, and behavioral covariates. OUTCOMES: In this longitudinal cohort of Brazilian men aged ≥40 years, unfavorable BMI trajectories-particularly becoming or remaining obese-were independently associated with greater odds of erectile dysfunction. These results reinforce obesity as a modifiable determinant of sexual and vascular health and emphasize the preventive value of long-term weight management. RESULTS: At follow-up, 44.3% of men no longer reported ED, while 32.0% had mild ED, 2.5% mild-to-moderate ED, 16.0% moderate ED, and 5.2% severe ED. Regarding BMI trajectories, 70.1% remained healthy, 3.9% became healthy, 4.1% became obese, and 21.9% remained obese. Men who became obese or remained obese had increased odds of ED (OR: 2.46, 95% CI, 1.15-5.27, P = 0.021; OR: 1.73, 95% CI, 1.22-2.45, P = 0.002, respectively). CLINICAL IMPLICATIONS: Proactive monitoring and management of unfavorable BMI trajectories may represent a practical and impactful strategy for preventing erectile dysfunction, underscoring the importance of integrating comprehensive weight management and lifestyle interventions into routine men's health and sexual medicine care. STRENGTHS AND LIMITATIONS: Key strengths include the longitudinal design, large sample size, and rigorous control for clinical and behavioral confounders. Limitations include the use of self-reported lifestyle variables, absence of hormonal data (particularly testosterone), and smaller sample sizes in certain BMI trajectory subgroups. CONCLUSION: Becoming or remaining obese significantly increased the risk of erectile dysfunction in men aged ≥40 years, independent of age, comorbidities, and lifestyle factors. These findings underscore the importance of sustained weight management across adulthood as a preventive strategy to preserve both cardiovascular and sexual health.