Night-time blood pressure load is associated with higher left ventricular mass index in renal transplant recipients

The absence of nocturnal fall in blood pressure (BP) is named as nondipper status, which has been shown to be an additional risk factor for the development of left ventricular hypertrophy and cardiovascular events in several high-risk groups. The aim of this study was to determine the influences of the nondipper status and nocturnal blood pressure loads on left ventricular mass index (LVMI) in renal transplant recipients. A total of 35 nondiabetic renal transplant recipients were included into the study. A 24-h ambulatory blood pressure monitoring (ABPM) was performed for all recipients. The nondipper status was defined as either an increase in night-time mean arterial pressure (MAP) or a decrease of no more than 10% of daytime MAP. LVMI was measured by using two-dimensional guided M-mode echocardiography. The night-time systolic blood pressure (SBP) load was defined as the percentage of the time, during which SBP exceeded 125 mmHg during night time. The nondipping was common among renal transplant recipients, of whom 60% were nondipper in our study. LVMI was significantly higher in the nondipper group vs the dipper group (133 +/- 35 g/m(2) vs 109 +/- 26 g/m(2), P = 0.04). A fall in MAP at night time was 14.5 +/- 4.3% in the dipper group, while it was 1.4 +/- 6.1% in the nondipper group (P < 0.001). On stepwise multiple regression analysis, night-time SBP load and haemoglobin were independent predictors of LVMI (R(2) = 0.53). In conclusion, nondipping is common after renal transplantation. Night-time SBP load and low haemoglobin are closely related to the increase in LVMI in renal transplant recipients. ABPM may be a more useful tool in optimizing treatment strategies to reduce cardio-vascular events in renal transplant recipients.

Prevalence of TT virus in a CAPD population

TT virus (TTV) has recently been identified in patients with post-transfusion non-A, non-G hepatitis. It is reported to be common in patients with a variety of liver diseases and with history of transfusion. Its pathogenesis in chronic liver diseases remains unclear. In this study, we have determined the prevalence of TTV in a continuous ambulatory peritoneal dialysis (CAPD) population and related its prevalence with history of previous hemodialysis, transfusion, HCV positivity and serum alanine amino-transferase (ALT) levels. TTV was detected in 44% of 63 CAPD patients and 30% of 43 healthy controls (p = 0.15). Frequency of TTV was similar in previously hemodialysed and never hemodialysed (8/14, 57% vs. 20/40, 41%, p = 0.15) and previously transfused and non-transfused (7/19, 37% vs. 15/44, 34%) CAPD patients. Prevalence of TTV was also similar in HCV(+) and HCV(-) patients. Serum ALT levels were 19 +/- 16 and 20 +/- 12 U/l in TTV(+) and TTV(-) patients, respectively. These results indicate that prevalence of TTV in a CAPD population is similar to healthy controls, and other routes of transmission in addition to parenteral routes might be involved in the transmission of TTV.

QT dispersion in renal transplant recipients

An increased QT dispersion (QTd) is associated with a variety of cardiac diseases and predicts sudden death. Although chronic renal failure patients and patients on hemodialysis are shown to have an increased QTd, evidence of increased QTd in renal transplant patients is scarce. In this study, renal transplant patients were evaluated to find out if they had an increased QTd. Thirty-four renal transplant recipients aged 35 +/- 8 years and 34 healthy control subjects aged 34 +/- 8 years were included in the study. The mean time after transplantation was 51.8 +/- 40.4 (range 5-154) months. The QT interval was measured by 12-lead electrocardiogram, and the QTd was defined as the difference between the maximum and minimum QT interval. Bazett's formula was used to correct for the heart rate (QTc). Both QTd and QTc dispersion (QTcd) in renal transplant patients were compared with those of control subjects. All patients underwent transthoracic echocardiographic assessment and 24-hour ambulatory blood pressure monitoring. Renal transplant recipients had similar QTd (37 +/- 15 vs. 39 +/- 17 ms) and QTcd (50 +/- 18 vs. 55 +/- 20 ms) compared to control subjects. QTd and QTcd were similar in patients with and without left ventricular hypertrophy (QTd 37 +/- 14 vs. 36 +/- 17 ms and QTcd 50 +/- 14 vs. 49 +/- 21 ms, respectively). No association was found between QTd and left ventricular mass index or blood pressure measurements. The QTd was not found to be increased in renal transplant recipients as compared with that of healthy controls in this study. Normalization of the QTd after renal transplantation may be through the correction of several factors responsible for increased QTd in uremic patients.

Urinary leucine aminopeptidase is a more sensitive indicator of early renal damage in non-insulin-dependent diabetics than microalbuminuria

We measured urinary activity of leucine aminopeptidase (EC 3.4.11.2) and creatinine concentrations (Cr, in mmol) in samples of second morning urine from 25 healthy subjects and 59 non-insulin-dependent diabetic (NIDD) subjects. If NIDD subjects are grouped according to their Alb/Cr ratio into normoalbuminuria (group A, Alb/Cr < 2.8 mg/mmol), microalbuminuria (group B, Alb/Cr 2.8-26.8 mg/mmol), and macroalbuminuria (group C, Alb/Cr > 26.8 mg/mmol), LAP/Cr ratios in all three groups exceeded those for healthy age-matched controls. Moreover, this ratio was higher in group B than in group A. The value for LAP/Cr was clearly abnormal (i.e., exceeded the upper limit of normal, log normal + 2 SD, found in healthy subjects) in 44% of group A. In the first 10-year period Of NIDD, prevalance of abnormal LAP/Cr ratio was 61.3%, whereas that of microalbuminuria was 35.5%. We have also found a LAP/Cr ratio abnormality of 91% in group B. Evidently, LAP/Cr may be increased early in NIDD subjects and be a more sensitive predictor of incipient nephropathy than microalbuminuria.