Many studies have reported that blood pressure (BP) response to dietary salt intake vary among individuals, which is a phenomenon described as salt-sensitivity of BP. Salt intake is an important risk of hypertension. In the present study, we evaluated the effect of 24hour urinary salt excretion and heart rate (HR) on blood pressure in young male normotensive Tanzanian.Design and Method:
Total 100 males aged 25 to 35 years, who were residents of seven wards in the Temeke district of Tanzania, were randomly invited to participate. 33 normotensive subjects in 100 participate were selected according to the criteria values, non-obese, systolic BP (SBP) <120 mmHg and diastolic BP (DBP) <80 mmHg. Subjects ingested 140mEq of a NaCl supplement for one week. Blood pressure and heart rate were measured before and after NaCl loading. Twenty four hour urine was collected and before and on the last day of salt loading phase.Results:
The subjects of 24hour urinary salt excretions higher than means, 5.05 g/day, were divided into higher and lower HR groups: HR ≤ the mean, 66.9 beats/min group (L-HR) and HR> the mean group (H-HR). The SBP, DBP and mean BP (MBP) were not significantly differences between groups before salt loading. At the last day of salt loading phase, DBP and MBP in H-HR (65.3 ± 2.3, 81.2 ± 2.3mmHg) tended to be higher than in L-HR (58.1 ± 2.7, 74.7 ± 2.1mmHg). The percent increases of SBP and MBP in H-HR (102.8 ± 2.2, 104.5 ± 2.8%) were significantly higher than in L-HR (95.1 ± 1.4, 94.9 ± 2.0%).Conclusions:
These findings of this study suggested the possibility that 24 hour urinary salt excretion and HR may become the simple marker of the salt-sensitive blood pressure elevation in young male normotensive Tanzanian.