Adherence to a DASH-Style Diet in Relation to Stroke: A Case-Control Study

Despite the growing body of evidence from Western societies on the association between dietary patterns and stroke, limited data are available in this regard from developing countries.

This study was conducted to examine the association between adherence to the Dietary Approaches to Stop Hypertension (DASH) diet and risk of stroke among the Iranian population.

This hospital-based case-control study included 194 stroke patients and 194 controls and was conducted at the Alzahra University Hospital, Isfahan, Iran. The cases were stroke patients who were hospitalized in the neurology ward of the Alzahra University Hospital. Controls were randomly selected from among hospitalized patients in the orthopedic or surgical wards of this center. A validated food frequency questionnaire (FFQ) was used to assess the patients' usual dietary intake. We constructed the DASH diet score based on food and nutrients emphasized or minimized in the DASH diet.

The prevalence of stroke among those in the top quartile of the DASH diet score was 40%, which was 15% lower than among those in the bottom quartile; this difference was marginally significant (p = 0.10). After controlling for age, sex, and total energy intake, adherence to the DASH diet was inversely associated with the risk of stroke (OR: 0.52; 95% CI: 0.28; 0.98). These associations remained significant even after additionally controlling for physical activity, smoking, hypertension, and diabetes, such that individuals in the highest quartile of the DASH diet score had a 58% lower risk of stroke than those in the lowest category (OR: 0.48; 95% CI: 0.24, 0.96). However, after further adjustment for body mass index (BMI), the association disappeared (OR: 0.62; 95% CI: 0.29, 1.31), indicating an obesity-dependent association.

We found an inverse relationship between the DASH-style diet and prevalence of stroke. Prospective studies are needed to confirm this association.