Longitudinal associations between changes in body mass index and erectile dysfunction

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.

We aimed to examine the longitudinal association between BMI trajectory patterns and erectile dysfunction among Brazilian men.

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.

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.

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).

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.

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.

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.