Description: Whether target organ damage is associated with blood pressure (BP) variability independent of level remains debated. We assessed these associations from 10-minute beat-to-beat, 24-hour ambulatory, and 7-day home BP recordings in 256 untreated subjects referred to a hypertension clinic. BP variability indices were variability independent of the mean, maximum–minimum difference, and average real variability. Effect sizes (standardized β) were computed using multivariable regression models. In beat-to-beat recordings, left ventricular mass index (n=128) was not ( P ≥0.18) associated with systolic BP but increased with all 3 systolic variability indices (+2.97–3.53 g/m 2 ; P 〈0.04); the urinary albumin-to-creatinine ratio increased ( P ≤0.03) with systolic BP (+1.14–1.17 mg/mmol) and maximum–minimum difference (+1.18 mg/mmol); and pulse wave velocity increased with systolic BP (+0.69 m/s; P 〈0.001). In 24-hour recordings, all 3 indices of organ damage increased ( P 〈0.03) with systolic BP, whereas the associations with BP variability were nonsignificant ( P ≥0.15) except for increases in pulse wave velocity ( P 〈0.05) with variability independent of the mean (+0.16 m/s) and maximum–minimum difference (+0.17 m/s). In home recordings, the urinary albumin-to-creatinine ratio (+1.27–1.30 mg/mmol) and pulse wave velocity (+0.36–0.40 m/s) increased ( P 〈0.05) with systolic BP, whereas all associations of target organ damage with the variability indices were nonsignificant ( P ≥0.07). In conclusion, while accounting for BP level, associations of target organ damage with BP variability were readily detectable in beat-to-beat recordings, least noticeable in home recordings, with 24-hour ambulatory monitoring being informative only for pulse wave velocity.

Description: There is abundant evidence that sodium intake is related to blood pressure. However, the relationship varies between individuals and is probably determined by renal sodium handling. We investigated clinic and ambulatory blood pressure in relation to interactions between sodium dietary intake and renal handling, as assessed by 24-hour urinary sodium excretion and endogenous lithium clearance, respectively. We calculated fractional excretion of lithium and fractional distal reabsorption rate of sodium, as markers of proximal and distal sodium handling, respectively. The 766 subjects included 379 men and 478 ambulatory hypertensive patients. They were never treated (n=697) or did not take antihypertensive medication for ≥2 weeks (n=69). In adjusted analyses, none of the associations of urinary sodium excretion, fractional excretion of lithium, and fractional distal reabsorption rate of sodium with clinic or ambulatory blood pressure were statistically significant ( P ≥0.09). However, there was significant ( P =0.01) interaction between urinary sodium excretion and fractional excretion of lithium in relation to nighttime diastolic blood pressure. In tertile 3 but not tertiles 1 and 2 of fractional excretion of lithium, nighttime diastolic pressure was positively associated with urinary sodium excretion ( P =0.03). However, nighttime diastolic pressure was higher in tertile 1 than tertile 3 of fractional excretion of lithium (+2.0 mm Hg; P =0.01), especially in the bottom tertile of urinary sodium excretion (+4.9 mm Hg; P 〈0.001). Similar trends were observed for nighttime systolic pressure and clinic and 24-hour diastolic pressure. In conclusion, sodium dietary intake and proximal tubular handling interact to be associated with blood pressure.

Description: Pulse wave velocity (PWV) is a measure of arterial stiffness and predicts cardiovascular events and mortality in the general population and various patient populations. In the present study, we investigated the predictive value of brachial-ankle PWV for mortality in an elderly Chinese population. Our study subjects were older (≥60 years) persons living in a suburban town of Shanghai. We measured brachial-ankle PWV using an automated cuff device at baseline and collected vital information till June 30, 2013, during follow-up. The 3876 participants (1713 [44.2%] men; mean [±SD] age, 68.1±7.3 years) included 2292 (59.1%) hypertensive patients. PWV was on average 17.8 (±4.0) m/s and was significantly ( P 〈0.0001) associated with age ( r =0.48) and in unadjusted analysis with all-cause (n=316), cardiovascular (n=148), stroke (n=46), and noncardiovascular mortality (n=168) during a median follow-up of 5.9 years. In further adjusted analysis, we studied the risk of mortality according to the decile distributions of PWV. Only the subjects in the top decile (23.3–39.3 m/s) had a significantly ( P ≤0.003) higher risk of all-cause mortality (hazard ratio relative to the whole study population, 1.56; 95% confidence interval, 1.16–2.08), especially in hypertensive patients (hazard ratio, 1.86; 95% confidence interval, 1.31–2.64; P =0.02 for the interaction between PWV and hypertension). Similar trends were observed for cardiovascular, stroke, and noncardiovascular mortality, although statistical significance was not reached ( P ≥0.08). In conclusion, brachial-ankle PWV predicts mortality in elderly Chinese on the conditions of markedly increased PWV and hypertension.