Mediterranean versus Dietary Approaches to Stop Hypertension (DASH) Diets and Heart Failure Risk: A UK Biobank Study

Interest in nutritional strategies for heart failure (HF) has grown substantially in recent years, reflecting the debilitating nature of the condition. The Mediterranean (Med) and Dietary Approaches to Stop Hypertension (DASH) diets have been identified as potential adjunctive approaches that may support the management of HF. However, while higher adherence to both diets reduces cardiovascular risk, their comparative associations with HF are unclear.

To estimate associations between adherence to the Med and DASH diet and incident HF.

A prospective cohort of UK Biobank participants, free of HF at baseline (2006-2010), was followed to 2024. Dietary Intake was assessed using 2 or more 24 hour dietary recalls, from which Med and DASH scores were derived and grouped into quintiles. Fine-Gray competing-risk Cox models estimated hazard ratios (HRs) and 95% CIs for a composite of incident HF or HF-related death, accounting for all-cause mortality. Model 1 adjusted for age, sex, smoking and sociodemographic factors. Model 2 further adjusted for obesity, hypertension, and type 2 diabetes, recognised risk factors and mediators on the causal pathway to HF. Food components that were not shared across both dietary patterns-for example, polyunsaturated fatty acids (PUFA)-were examined independently using the same multivariable models.

Among 124 777 participants (mean age 56±8 years; 56% female) followed for 12 years, 2,931 (2.35%) HF events and 441 (0.35%) HF deaths occurred. In Model 1, highest vs lowest adherence was associated with lower HF risk for both diets (Med: aHR 0.88, 95% CI 0.79, 0.99; DASH: aHR 0.79, 95% CI 0.70, 0.89). In Model 2, the Med association was attenuated (HR 0.92, 95% CI 0.82, 1.03), while DASH remained significant (HR 0.89, 95% CI 0.79 , 1.00) In Model 2, higher polyunsaturated fatty acid (PUFA) intake was associated with lower HF risk (HR 0.87, 95% CI 0.77, 0.98).

Higher adherence to Med and DASH diets is associated with lower HF risk; but only DASH retained an independent significant association after adjusting for cardiometabolic mediators. However causal inferences cannot be made. Increasing PUFA intake, which is not captured in standard Med or DASH scoring, may confer additional reductions in HF risk and should be viewed as an exploratory, hypothesis-generating observation.