Abstract
OBJECTIVE: This study is the first study in Middle Eastern population that aimed to investigate the association between global diet quality score (GDQS) and risk of hypertension (HTN) in Iranian adults. DESIGN: This population-based cohort study was conducted on 5718 individuals aged ≥ 18 years from the third and fourth Tehran Lipid and Glucose Study surveys, who were followed until the sixth survey (mean follow-up: 7·8 years). Dietary data were collected using a validated FFQ to calculate GDQS as a novel food-based metric designed to assess diet quality across diverse populations. It evaluates the adequacy of healthy food groups (e.g. fruits, vegetables and whole grains) while monitoring the moderation of unhealthy or excessive intake (e.g. refined grains, processed meats and sugary foods). SETTING: Tehran Lipid and Glucose Study. PARTICIPANTS: Iranian men and women. RESULTS: Participants had a mean (sd) age of 37·7 (sd 12·8) years, BMI of 26·6 (sd 4·7) kg/m(2) and GDQS of 25·3 (sd 4·4). During the 7·8-year follow-up, 1302 (18 %) new cases of HTN were identified. Higher GDQS and its healthy components were associated with reduced HTN risk (hazard ratio (HR): 0·83; 95 % CI: 0·70, 0·98; P(trend) = 0·034 and HR: 0·78; 95 % CI: 0·65, 0·92; P(trend) = 0·005, respectively), while unhealthy components of GDQS showed no association with HTN risk (HR: 1·14; 95 % CI: 0·98, 1·33; P(trend) = 0·059). These protective associations were observed across all weight categories and both genders, with stronger effects among obese individuals (for GDQS: HR: 0·75; 95 % CI: 0·58, 0·98; P = 0·041; for healthy components: HR: 0·75; 95 % CI: 0·57, 0·99; P = 0·044) and females (for GDQS: HR: 0·77; 95 % CI: 0·62, 0·97; P = 0·028; for healthy components: HR: 0·76; 95 % CI: 0·60, 0·96; P = 0·023). CONCLUSIONS: A higher GDQS was associated with a reduced risk of incident HTN among Iranian adults. Adherence to a high-quality diet, particularly focusing on the healthy dietary components of GDQS, may serve as an effective strategy for preventing HTN, especially among obese individuals and women.