Pulse pressure responses to psychological tasks improve the prediction of left ventricular mass: 10 years of follow-up

Comparison of 44-hour and fixed 24-hour ambulatory blood pressure monitoring in dialysis patients

The two most commonly used strategies to evaluate dialysis patients' blood pressure (BP) level are 44-hour and 24-hour ambulatory blood pressure monitoring (ABPM). The objective of this study was to find an appropriate 24-hour period that correlated well with the 44-hour BP level and determine the differences between these strategies. In a group of 51 dialysis patients, the authors performed 44-hour ABPM and extracted data for a fixed 24-hour ABPM. The fixed 24-hour ABPM started at 6 am on the nondialysis day. A strong correlation was found between all parameters of 44-hour and the fixed 24-hour ABPM, with paired sample t test showing only small magnitude changes in a few parameters. Both 24-hour ABPM and 44-hour ABPM were superior to clinic BP in predicting left ventricular mass index (LVMI) by multiple regression analysis. It was found that 44-hour ambulatory arterial stiffness index (AASI), but not 24-hour AASI, had a positive association with LVMI (r=0.328, P=.021). However, after adjustment for 44-hour systolic blood pressure, this association disappeared. Fixed 24-hour ABPM is a good surrogate of 44-hour ABPM to some extent, while 44-hour ABPM can provide more accurate and detailed information.

Left ventricular hypertrophy in nondiabetic predialysis CKD

BACKGROUND

Although left ventricular hypertrophy (LVH) is a strong predictor of mortality in patients with end-stage renal disease, few studies are available before the start of dialysis treatment. The purpose of this study is to evaluate the prevalence and clinical correlates of LVH in nondiabetic patients with chronic kidney disease (CKD) not yet undergoing renal replacement therapy.

METHODS

We investigated 244 nondiabetic patients with CKD; 57 patients (42 men; age, 20 to 78 years) had stages 1 to 2 CKD and 187 patients (122 men; age, 18 to 77 years) had stages 3 to 5 CKD. Fifty-two normotensive healthy subjects served as controls. Each patient had blood pressure (BP) measured by means of 24-hour ambulatory BP monitoring and left ventricular mass index (LVMi) assessed by means of M-mode echocardiography. Creatinine clearance was estimated by means of the Cockcroft-Gault formula, and hemoglobin, serum lipid, and intact parathyroid hormone concentrations and daily urinary protein excretion were assessed by using routine methods.

RESULTS

In the overall group, prevalences of arterial hypertension and LVH were 66% and 74%, respectively. LVMi was 160 +/- 50 g/m2 body surface area and associated directly with age (P = 0.0013), duration of arterial hypertension (P = 0.0075), 24-hour systolic BP (P = 0.0113), pulse pressure (P = 0.0003), daytime (P = 0.0206) and nighttime systolic BP (P = 0.0059), and urinary protein excretion (P < 0.05) and inversely with creatinine clearance (P = 0.0103) and hemoglobin level (P = 0.0276). In patients with CKD stages 1 to 2 (LVH prevalence, 51%), age, duration of arterial hypertension, pulse pressure, and urinary protein excretion were significant predictors of LVMi (P < 0.00002) by using stepwise regression analysis, whereas in those with CKD stages 3 to 5 (LVH prevalence, 78%), pulse pressure emerged as the sole predictor of LVMi (P = 0.0011).

CONCLUSION

The prevalence of LVH in nondiabetic predialysis patients with CKD is greater than previously reported, and there is evidence that LVH already is present in the early stages of renal disease. Arterial hypertension is associated with LVH in patients with CKD, and the strong relationship between elevated pulse pressure and LVH in those with more advanced CKD suggests that increased arterial stiffness might have a role for LVH well before the start of dialysis therapy.

Connecting with others in the midst of stressful upheaval on September 11, 2001

This study was originally planned from September tenth through twelfth to assess concurrent use of three real-time data sources during a usual day. When the World Trade Center towers collapsed, the plan expanded to describe 24-hour blood pressure and heart rate, natural environment word use, television viewing/radio listening, and self-reported diary feelings for six undergraduate students in the midst of stressful upheaval. Heart rate, "we" word-use and television viewing/radio listening increased over time. Higher negative and lower positive feelings/emotions occurred during morning hours on September 11. Students connected with others and shared good thoughts. Measurement with real-time data sources was informative.