Association of Adherence to the Dietary Approach to Stop Hypertension and Mediterranean Diets with Blood Pressure in a Non-Hypertensive Population: Results from Isfahan Salt Study (ISS)

Abstract Background and Aims Hypertension is among the major risk factors for cardiovascular events in the Iranian population. This cross-sectional study was designed to examine the association of adherence to the dietary approaches to stop hypertension (DASH) and Mediterranean (MED) dietary patterns with distribution of blood pressure and pre-hypertension prevalence. Methods and Results This cross-sectional study was carried out in 1363 non-hypertensive adults. Adherence to the DASH and MED diets was calculated using a semi-quantitative food frequency questionnaire (FFQ). Hypertension was measured by standard method. Multiple logistic regression was applied to obtain the odds ratio of pre-hypertension in the tertiles of MED and DASH dietary patterns. Compared to the lowest, participants with the highest adherence to the DASH dietary pattern had significantly lower systolic blood pressure (SBP) (111.3±11.8 vs. 112.8±12.5; P=0.010) and diastolic blood pressure (DBP) (70.7±9.2 vs. 71.8±9.8; 0.042). There was no significant difference in the mean SBP and DBP among the participants across tertiles of MED or diet adherence. Higher scores of the DASH and MED diets were inversely associated with lower SBP after adjustment for all potential confounders (OR=-0.04, 95% CI=-0.29, -0.01, P=0.039) and (OR=-0.04, 95% CI=-0.72, -0.02, P=0.044), respectively. Also, DASH and MED dietary patterns was associated with reduced OR of pre-hypertension occurrence by 13% (OR: 0.87; 95% CI: 0.70- 0.98; P for trend=0.042) and 16% ([OR: 0.84; 95% CI: 0.69-0.97; P trend =0.035), respectively. Conclusion Adherence to the DASH and MED diets was inversely associated with the odds for pre-hypertension and systolic blood pressure.