[Aim] To evaluate the correlations between nighttime blood pressure, morning blood pressure and health-related quality of life (HRQOL) in hypertensives.
[Methods] Thirty-eight participants, (18 male and 20 female, average age 52 years) were studied and circadian blood pressure and minimal sleep-time blood pressure (BPo : base BP) were measured using TM2425. The high-frequency component (HF) and low-frequency component (LF) of HR variability were determined by means of power spectrum analysis. The nocturnal systolic blood pressure fall (dipSBP) was calculated as 100× (1-sleepSBP / awakeSBP). HRQOL was assessed by Medical Outcome Study Short-Form 36-Item Health Survey (SF-36). The morning BP surge (MS) was calculated as follows : mean SBP for two hours before and after awakening. The morning BP (MS₂) was calculated as follows : mean SBP during the 2 hours after awakening minus base systolic blood pressure (SBPo).
[Results] The scores of SF-36 scales (general health) were significantly lower in nondippers than dippers. Using multiple regression analysis, dipSBP was found to be correlated with MS₁ (p<0.01), the scores of general health (p<0.03) and sleep LF/HF (p<0.04). SBPo positively correlated with morning SBP (r=0.61, p<0.01). SBPo negatively correlated with the scores of SF-36 scales (mental health) (r=-0.41, p<0.02). Using multiple regression analysis, SBPo was also found to be correlated with MS₂ (p<0.01), the scores of mental health (p<0.03), 24-h MBP (p<0.01) and 24-hour urinary sodium excretion (p<0.05).
[Conclusions] The scores of SF-36 scales (general health) were significantly lower in nondippers than dippers. SBPo closely correlated with morning BP and poor scores of HRQOL.

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The purpose of this study was to estimate 24-hour urinary salt and potassium excretion (Q_24NaCl and Q, respectively) from the first morning voided urine specimens (Q8_NaCl and Q_8K). Data was collected from 5 subjects over a period of 1 month and regression analyses were performed to estimate Q_24NaCl and Q_24k from Q_24K from_Q_8NaCl and Q_8K. The correlation formulas obtained were :
Solt : Q_24NaCl=2.35×Q_8Nacl+3.80 (Correlation coefficient 0.80)
Potassium : Q_24K=2.66×Q_8K+2.66 (correlation coefficient 0.63)
The maximum target intakes for potassium and sodium, as recommended by Healthy Japan 21, were converted into equivalent urinary excretion values for comparison. While our measured values for both solt and potassium, Q_24NaCl and Q_24K, did not exceed the targeted recommendations, room for improvement in dietary habits was indicated. Our results also indicate the possibility of further study into the correlation of solt and potassium to amount of meals and to a meal balance index.

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