Adherence to dietary guidelines is associated with a lower risk of long-term cardiovascular mortality after myocardial infarction: a prospective analysis in the Alpha Omega Cohort.

Aims: Dietary guidelines specifically for patients with atherosclerotic cardiovascular disease (CVD) were investigated in relation to long-term mortality after myocardial infarction (MI). Methods: We included 4365 MI patients of the prospective Dutch Alpha Omega Cohort (60-80 years, 80 % male). We created the Dutch Healthy Diet-Cardiovascular Disease (DHD-CVD) index, based on the 2023 Dutch dietary guidelines for CVD patients with dietary data from a validated 203-item questionnaire. Hazard Ratios (HRs) for CVD-related and all-cause mortality across quartiles of the DHD-CVD index (ref=Q1, low diet quality) and per 1-SD increment were estimated using multivariable Cox regression models. Effect modification by health determinants was examined through stratification. Numbers needed to eat (NNE) were calculated as 1 divided by the 10-year risk reduction between extreme quartiles. Results: The mean DHD-CVD score was 88.9 ± 14.8. During a median follow-up of 14.6 years (56,037 person-years), 2869 deaths occurred, including 1112 from CVD. High vs. low diet quality was associated with a 22 % lower risk of CVD mortality (HR:0.78, 95 %CI: 0.66, 0.93), with an HR of 0.91 (95 %CI:0.86, 0.97) per 1-SD. For all-cause mortality, HRs were 0.84 (0.76, 0.94) for high vs low and 0.93 (0.90, 0.97) per 1-SD. Associations for CVD mortality were more pronounced in patients with obesity or impaired kidney function. The NNE was 13 for CVD mortality and 77 for all-cause mortality. Conclusion: Better adherence to dietary guidelines for CVD patients was associated with lower CVD and all-cause mortality risks after MI and could be an effective strategy to lower cardiovascular risk.