Consistency with the DASH diet and incidence of heart failure

Abstract

Background: The Dietary Approaches to Stop Hypertension (DASH) diet effectively reduces blood pressure. In observational studies, the association between diets consistent with DASH and risk of coronary heart disease and stroke has been examined with varying results. We hypothesized that diets consistent with the DASH diet would be associated with a lower incidence of heart failure (HF).

Methods: We conducted a prospective observational study in 36 019 participants in the Swedish Mammography Cohort who were aged 48 to 83 years and without baseline HF, diabetes mellitus, or myocardial infarction. Diet was measured using food-frequency questionnaires. We created a score to assess consistency with the DASH diet by ranking the intake of DASH diet components and 3 additional scores based on food and nutrient guidelines. Cox proportional hazards models were used to calculate rate ratios of HF-associated hospitalization or death, determined using the Swedish inpatient and cause-of-death registers between January 1, 1998, and December 31, 2004.

Results: During 7 years, 443 women developed HF. Women in the top quartile of the DASH diet score based on ranking DASH diet components had a 37% lower rate of HF after adjustment for age, physical activity, energy intake, education status, family history of myocardial infarction, cigarette smoking, postmenopausal hormone use, living alone, hypertension, high cholesterol concentration, body mass index (calculated as weight in kilograms divided by height in meters squared), and incident myocardial infarction. Rate ratios (95% confidence intervals) across quartiles were 1 [Reference], 0.85 (0.66-1.11), 0.69 (0.54-0.88), and 0.63 (0.48-0.81); P(trend) < .001. A similar pattern was seen for the guideline-based scores.

Conclusion: In this population, diets consistent with the DASH diet are associated with lower rates of HF.

Figure 1

The solid line represents the incidence rate ratio of heart failure and dashed lines represent 95% confidence intervals. Penalized cubic splines with 3 degrees of freedom were used to flexibly model the shape of the association. Cox proportional hazards models with baseline hazard allowed to vary by age and additionally adjusted for physical activity (linear), energy intake (linear), education (less than high school, high school, university), family history of myocardial infarction at less than 60 years (yes, no), cigarette smoking (current, past, never), living alone (yes, no), postmenopausal hormone use (yes, no), self-reported history of hypertension and high cholesterol, body mass index (linear), and incident myocardial infarction (time varying: no myocardial infarction, myocardial infarction in the previous year, more distant history of myocardial infarction).

Figure 2

The circles represent the incidence rate ratios of heart failure comparing the top to bottom quartiles of the DASH component score, and lines represent 95% confidence intervals. P-values are for tests of the difference in estimates between those with and without self-reported hypertension, self-reported high cholesterol, current cigarette smoking, and body mass index ≥ 25 kg/m². Cox proportional hazards models with baseline hazard allowed to vary by age and additionally adjusted for physical activity (linear), energy intake (linear), education (less than high school, high school, university), family history of myocardial infarction at less than 60 years (yes, no), cigarette smoking (current, past, never), living alone (yes, no), postmenopausal hormone use (yes, no), self-reported history of hypertension and high cholesterol, body mass index (linear), and incident myocardial infarction (time varying: no myocardial infarction, myocardial infarction in the previous year, more distant history of myocardial infarction).