Introduction: Despite growing calls to tackle aging-related cardiovascular disease (CVD), the role of detecting early diastolic dysfunction such as those observed in aging, prior to clinical disease, is of unclear clinical benefit. Methods: Myocardial function determined by echocardiography was examined in association with incident cardiovascular outcomes or all-cause death by Cox proportional hazards model. Sex-based differences in outcomes were included. Results: A total of 956 participants (mean age 63 ± 12.9 years, n = 424 males [44%]) were categorized based on mitral peak early-to-late diastolic filling velocity (E/A) ratios: E/A <0.8 (28%), E/A 0.8–1.2 (39%), E/A (29%), E/A >2.0 (4%). Incidence rate (IR) for non-fatal cardiovascular outcomes was 2.83 per 100 person-years (95% CI: 2.24–3.56) and 0.45 per 100 person-years (95% CI: 0.26–0.80) for all-cause death. Event-free survival from non-fatal cardiovascular outcomes was significantly different among E/A categories (log-rank p = 0.0269). E/A <0.8 (HR 1.80, 95% CI: 1.031, 3.14, p = 0.039) was associated with non-fatal cardiovascular outcomes. Among men, IR for cardiovascular outcomes was 3.56 per 100 person-years (95% CI: 2.62–4.84) and 0.75 per 100 person-years (95% CI: 0.39–1.44) for all-cause death. Among women, IR for cardiovascular outcomes was 2.22 per 100 person-years (95% CI: 1.56–3.16) and 0.21 per 100 person-years (95% CI: 0.067–0.64) for all-cause death. For E/A <0.8 category, women had significantly higher risks of non-fatal cardiovascular outcomes, compared to E/A 0.8–1.2 category (HR 2.49, 95% CI: 1.18, 5.23, p = 0.017). Conclusion: Myocardial aging was an independent predictor of cardiovascular outcomes in community-dwelling older adults prior to clinical CVD. Impaired myocardial relaxation was prevalent in both sexes but associated with worse outcomes in women, suggestive of sex differences in age-related biology.