Subjects Mean Blood Pressure Research Articles

Greater adherence to the dietary approaches to stop hypertension (DASH) dietary pattern is associated with lower blood pressure in healthy Iranian primary school children.

The dietary determinants of children blood pressure (BP) are poorly understood. We examined the association between adherence to the dietary approaches to stop hypertension (DASH) dietary pattern and BP in healthy Iranian primary school children. This cross-sectional study was conducted among a representative sample (n = 407) of healthy Shirazi students aged 6-12 years. Subjects' systolic and diastolic BP were measured by a validated oscillometric BP monitor. Usual dietary intakes over the past 12 months were assessed using a valid and reproducible 168-item semi-quantitative food frequency questionnaire via face-to-face interviews. A DASH score was calculated for each subject based on his/her energy-adjusted intakes of 8 major dietary components emphasized or minimized in the DASH dietary pattern. The higher the DASH score of a subject, the more his/her adherence to the DASH dietary pattern. After controlling for several potential confounders in the analysis of covariance models, multivariable-adjusted means of systolic and mean BP of subjects in the highest tertile of DASH score were significantly lower than those in the lowest tertile (for systolic BP: mean difference -6.2mmHg, P = 0.010; and for mean BP: mean difference -5.4mmHg, P = 0.013). Furthermore, a similar but statistically insignificant difference was found in terms of multivariable-adjusted means of diastolic BP (mean difference -3.9mmHg, P = 0.146). The findings suggest that greater adherence to the DASH dietary pattern is associated with lower BP in healthy Iranian primary school children. However, future prospective studies of adequate methodological quality are warranted to confirm these findings.

A Western dietary pattern is associated with higher blood pressure in Iranian adolescents.

The dietary determinants of adolescent blood pressure (BP) are not well understood. We determined the association between major dietary patterns and BP in a sample of Iranian adolescents. This cross-sectional study was conducted among a representative sample (n=557) of Shirazi adolescents aged 12-19years. Participants' systolic and diastolic BP was measured using a validated oscillometric BP monitor. Usual dietary intakes during the past 12months were assessed using a valid and reproducible 168-item semiquantitative food frequency questionnaire through face-to-face interviews. Principal component factor analysis was used to identify major dietary patterns based on a set of 25 predefined food groups. Overall, three major dietary patterns were identified, among which only the Western pattern (abundant in soft drinks, sweets and desserts, salt, mayonnaise, tea and coffee, salty snacks, high-fat dairy products, French fries, and red or processed meats) had a significant association with BP. After adjusting for potential confounders in the analysis of covariance models, multivariable adjusted means of the systolic and mean BP of subjects in the highest tertile of the Western pattern score were significantly higher than those in the lowest tertile (for systolic BP: mean difference 6.9mmHg, P=0.001; and for mean BP: mean difference 4.2mmHg, P=0.003). A similar but statistically insignificant difference was observed in terms of diastolic BP. The findings suggest that a Western dietary pattern is associated with higher BP in Iranian adolescents. However, additional large-scale prospective studies with adequate methodological quality are required to confirm these findings.

Evaluation of regional haemodynamics and alterations of vascular wall of the lower limbs in hypertensive subjects.

This study was designed to analyse the relationship between arterial hypertension and changes in arterial blood flow and vascular wall damage of the lower limbs in hypertensive patients with various degrees of hypertension. Six hundred and fifty-four hypertensive patients (421 males and 233 females) aged 35 to 70 years and 88 healthy subjects (63 males and 25 females) aged 39 to 60 years were studied. Strain-gauge plethysmography of the lower limbs was used to calculate arterial calf blood flow (RF), arterial calf blood flow after post-ischaemic hyperaemia (PF), basal and minimal vascular resistances (BVR and MVR), time to reach peak flow (tPF), time until 50% reduction of peak flow (tT1/2) and total recovery time (tT). In 108 (67 males and 41 females) of the hypertensive patients, a morphological study by echo-Doppler duplex scanning of the popliteal artery was performed to measure medial-intimal thickening and popliteal lumen diameter. Our results indicate that regional haemodynamics of the lower limbs worsened in hypertensives in comparison with control subjects. In addition, the change in peripheral haemodynamics was related to the degree of hypertension. Moreover, medial--intimal thickening was significantly (P < 0.05) higher in severe hypertensives than mild hypertensives. Popliteal lumen diameter was significantly (P < 0.05) lower in severe hypertensives than moderate and mild hypertensives. In all these subjects mean blood pressure was correlated directly (r = 0.31; P < 0.001) with medial-intimal thickening and inversely (r = -0.37; P < 0.001) with popliteal lumen diameter. Multiple regression analysis indicated that mean blood pressure, age and serum cholesterol were independently correlated to medial-intimal thickening. This relationship was not influenced by the diabetic patients and smokers among the groups. Our results indicate that hypertension impairs peripheral flow and encourages the development of medial-intimal thickening.