Chronotherapy for morning blood pressure surge in hypertensive patients: a systematic review and meta-analysis

Background The morning blood pressure surge (MBPS) is related to an exaggerated risk of cardiovascular diseases and mortality. With increasing attention on circadian change in blood pressure and extensive use of ambulatory blood pressure monitoring (ABPM), chronotherapy that administration of medication according to biological rhythm, is reported to improve cardiovascular outcomes. The aim of this study is to evaluate the influence of chronotherapy of antihypertensive drugs upon MBPS in hypertensive patients. Methods A search strategy was applied in Ovid MEDLINE, EMBASE, Cochrane (Wiley) CENTRAL Register of Controlled Trials, Cochrane Database of Systematic Reviews, and the Chinese Biomedical literature database. No language and date restrictions. Randomized controlled trials (RCT) assessing the efficacy of evening and morning administration of the same medications in adult patients with primary hypertension were included. Results A total of ten trials, comprising 1724 participants with a mean age of 61 and 51% female, were included in this study. Combined analysis observed significant reduction of MBPS (− 5.30 mmHg, 95% CI − 8.80 to − 1.80), night-time SBP (− 2.29 mmHg, 95% CI − 4.43 to − 0.15), night-time DBP (− 1.63 mmHg, 95 %CI − 3.23 to − 0.04) and increase in night blood pressure dipping (3.23%, 95% CI 5.37 to 1.10) in evening dosage compared with traditional morning dosage of blood pressure-lowering drugs. No significant difference was found in the incidence of overall adverse effects (RR 0.65, 95% CI 0.30 to 1.41) and withdrawal due to adverse effects (RR 0.95, 95% CI 0.53 to 1.71). Conclusions Our study suggested that evening administration of antihypertensive medications exerted better blood pressure-lowering effect on MBPS compared with conventional morning dosage. Safety assessment also indicated that the evening regimen did not increase the risk of adverse events. However, endpoint studies need to be carried out to confirm the significance and feasibility of this treatment regimen in clinical practice.

Interaction of the endothelin system and calcineurin inhibitors after kidney transplantation

Plasma endothelin (ET)-1 concentrations have been shown to be elevated in patients receiving calcineurin-inhibitors (CI). We investigated urinary and plasma ET-1 (uET-1, pET-1), BigET-1 (uBigET-1, pBigET-1) concentrations, and plasma soluble endothelin-converting enzyme (ECE) concentrations in 381 adult caucasian kidney allograft recipients with graft survival of more than 2 years from the outpatients department of our clinic. Blood and urine probes were always drawn immediately before morning dosage of immunosuppressants. Mean of urinary protein excretion (meanProt) and mean of serum creatinine (meanCrea) were calculated from all available measurements in the most recent year. uET-1 and uBigET-1 were adjusted for urinary protein excretion by calculating uET-1/meanProt and uBigET-1/meanProt. Patients (n = 310) were on a cyclosporine A or FK506 (CI-group) based immunosuppression protocol, and 71 patients were immunosuppressed without use of CI (nonCI group). Time since transplantation was similar in both groups (mean±S.D.; CI-group: 7.55±2.50; nonCI-group: 7.74±3.06 years, P = 0.240) as well as meanCrea (mean±S.D.; CI-group: 1.97±1.34; nonCI-group: 1.77±1.29mg/dl, P = 0.326). pET-1 was significantly higher in the CI-group, compared with nonCI (mean±S.D.; 0.87±1.4 versus 0.56±0.76fmol/ml, P = 0.011). pBigET-1 was similar (mean±S.D.; 0.85±1.41 versus 0.70±1.21fmol/ml, P = 0.33). ECE concentrations were higher in the CI group (mean±S.D.; 14.30±18.02 versus 9.23±7.42ng/ml, P = 0.001). uET-1/meanProt and uBigET-1/meanProt concentration were similar in the CI-group compared with the nonCI-group (mean±S.D.; uET-1/meanProt: 15±24 versus 21±40pmol/g, P = 0.139; uBigET-1/meanProt: 34±55 versus 19±23pmol/g, P = 0.248). pET-1 elevation in patients receiving CI might be more likely to be due to elevated conversion of pBig-ET-1 by more ECE, and not to higher concentrations of pBigET-1.

Activity of the endothelin system in kidney allograft recipients is not associated with progression of chronic graft dysfunction

Endothelin (ET) A receptor antagonists have been shown to be beneficial in rat models of chronic kidney allograft dysfunction. We investigated urinary and plasma ET-1 (uET-1, pET-1) and BigET-1 (uBigET-1, pBigET-1) concentrations, and plasma soluble ET-converting enzyme (ECE) concentration in 310 adult Caucasian kidney allograft recipients with graft survival of more than 2 years from the outpatients department of our clinic. All patients were on cyclosporine A- or FK506-based immunosuppression protocols. From all available measurements since transplantation, we calculated the slope of serum creatinine-1/year (slopeCrea) as a parameter for progression of chronic graft dysfunction, as well as the mean of serum creatinine (meanCrea) from most recent year before measurements as a parameter for actual graft function. The slope of urinary protein excretion/year (slopeProt) and mean of urinary protein concentration (meanProt) from most recent year was calculated analogue. uET-1 and uBigET-1 were adjusted for protein excretion by calculating uET-1/meanProt and uBigET-1/meanProt. Blood and urine probes for measurements were always drawn immediately before morning dosage of immunosuppressants. There was no significant correlation of any measured component of the ET system with slopeCrea or slopeProt. MeanCrea (mg/dl) was significantly correlated with pBigET-1 (fmol/ml) and pET-1 (fmol/ml) (pBigET-1: r = 0.179, P = 0.001; pET-1: r = 0.161, P = 0.009). The other measured components of the ET systems were not significant correlated with meanCrea. In conclusion, the actual graft function is associated with elevated pET-1 and BigET-1 concentrations as it is well known from other forms of impaired kidney function. However, the actual concentration of ET-1, soluble ECE, and BigET-1 in urine and plasma in our study is not associated with parameters for progression of chronic graft dysfunction.

Medicating Students with Emotional and Behavioral Disorders and ADHD: A State Survey

Three-hundred and ninety-six teachers of students with emotional and behavioral disorders (EBD) in Wisconsin provided information about 1,300 students in their classes who were receiving medication for treatment of Attention Deficit Hyperactivity Disorder (ADHD). Results of the survey revealed that 40% of elementary school, 32% of middle/junior high school, and 15% of high school students with EBD were identified as having ADHD and were being treated for it with medication. The teachers reported that the most common types of medication were Ritalin (66%), Dexedrine (11 %), Cylert (7%), and Imipramine (5%). The most frequent morning dosage for Ritalin and Dexedrine was 10 mgs. Teachers of students with EBD did not believe that ADHD was under-diagnosed, and they did believe that medication effectively reduced maladaptive behavior.

Deuterium dilution as a method for determining total body water: effect of test protocol and sampling time

Deuterium dilution for the measurement of total body water (TBW) has been conducted using varying protocols for equilibration. We measured TBW from deuterium dilution in urine samples in twenty-eight subjects using three protocols: (1) early morning dosage without breakfast, measuring deuterium in a second voiding at 4h and 6h; (2) early morning dosage with breakfast with the same measurement times; (3) dosage as last consumption before overnight sleep, measuring deuterium in a second voiding at 10 h. Results were compared with TBW estimates from underwater weighing (UWW). Because UWW is an indirect measure of TBW, it is used as an independent reference method in order to compare only relative discrepancies between the two methods. TBW values in the fasted state were not significantly different from those obtained in the fed state. The urinary deuterium enrichment was higher at 4 h than at 6 h (resulting TBW differences: 0·6 (SD 0·4)I). At 4h and 6h, differences in TBW measurements from deuterium and densitometry were positively related to the amount of TBW, indicating incomplete equilibration in larger water compartments. At 10h no such relationship existed, indicating complete mixing of deuterium. It is concluded that 10h equilibration is preferable to the shorter 4h and 6h, for the determination of TBW.