Researcher(s)
- Abigail Thomas, Medical Diagnostics, University of Delaware
Faculty Mentor(s)
- Shannon Lennon, Kinesiology & Applied Physiology, University of Delaware
Abstract
Diets high in sodium can increase blood pressure (BP). While elevated BP can predict increased cardiovascular (CV) risk, it has been shown that BP variability (BPV) may be a better indicator. Limited research suggests that while women have a lower BP, they often exhibit greater BPV. The purpose of this study was to examine whether sodium density, calculated as dietary sodium intake relative to total energy intake, affects BPV differently in normotensive men and women. Fifty-five individuals (33W/22M; 29.5±8.7 years; SBP: 113±13 mmHg; DBP: 70±9 mmHg; BMI: 23.8±2.9 kg/m2) underwent ambulatory blood pressure monitoring for 24 hours. BPV was assessed using average real variability (ARV). During the same 24 hours, participants collected their urine. Participants recorded their dietary intake for 3 days and provided a blood sample. Data was analyzed using an unpaired t-test, and Pearson correlations were run to examine relations between sodium and BP and BPV. Absolute sodium intake was higher in men (3609±1167 mg) than women (2950±874 mg, p=0.03); however, once normalized to energy intake, it was no longer different (p=0.54). Twenty-four hour, daytime, and nighttime systolic BP (SBP) were all lower in women (all p<0.05); however, 24-hour, daytime, and nighttime diastolic BP (DBP) was not (all p>0.05). Twenty-four hour, daytime, and nighttime SBP and DBP ARV did not differ between women and men (all p>0.05). Furthermore, no significant relations were found between sodium density and SBP or DBP ARV in men (all p>0.05). However, sodium density was inversely related to both 24-hour and daytime SBP and DBP ARV in women (all p<0.05). While no differences between men and women were found in measures of BPV, an inverse relation between sodium density and BPV was found in women suggesting greater BPV at lower sodium intakes.