Associations between dietary patterns and blood pressure in a sample of Australian adults

BACKGROUND: Investigating effects of whole diets on blood pressure (BP) can contribute to development of diet-based recommendations for health. Our aim was to assess the relationship between dietary patterns and BP in a sample of free-living Australian adults. METHODS: Usual dietary patterns of participants recruited to dietary intervention studies were assessed using factor analysis (two 24-h recalls). The mean of seven days of daily, seated BP measurements were used. RESULTS: Complete data from 251 participants (112 males; mean age 55.1(9.1) (SD) years; body mass index (BMI) 29.5(3.9) kg/m(2)) was included. Three dietary patterns were identified. Only Dietary Pattern 2 was positively associated with home systolic BP (β = 1.88, 95% CI 0.16, 3.60) after adjusting for age, sex, BMI, anti-hypertensive medication, smoking, education, physical activity and energy intake. This dietary pattern was characterised by high consumption of low-fibre bread, pasta, noodles and rice, meat dishes, poultry dishes and egg dishes, mixed cereal dishes, salted nuts and low consumption of milk and yoghurt (low-fat), vegetable juice, vegetables and high-fibre bread. Dietary Pattern 2 was also positively associated with intakes of energy (P = 0.002) and sodium (P = 0.005) and inversely associated with potassium intake (P = 0.002). After adjustment for energy, only the inverse association with potassium remained (P < 0.001). CONCLUSIONS: In this sample of Australian adults, Dietary Pattern 2 was associated with higher BP and thus chronic disease risk, supporting the evidence that diets high in energy and sodium, and low in potassium from vegetables and dairy, are detrimental to cardiovascular health.