Ambulatory blood pressure monitoring after renal transplantation in children

The factors affecting blood pressure in pediatric renal transplant recipients

To investigate the parameters affecting systemic blood pressure in pediatric renal transplant recipients, we retrospectively examined the data from 19 adolescent renal transplant recipients including 6 girls overall, mean age of 15,47 +/- 3.56 years. Serum creatinine (Scr), fractional extraction of sodium (FENa), whole blood trough cyclosporine(C0), plasma total cholesterol (TC) and triglyceride levels, and systolic and diastolic blood pressure (SBP and DBP) were monitored during a total of 677 visits. SBP and DBP, classified as <95p (groups 1s and 1d) and >95p (groups 2s and 2d), were correlated with differences between groups 1 and 2. Group 2s Scr and FENa levels were higher than group 1s (P =.002 and P =.048, respectively), whereas C0 and FENa levels were higher in Group 2d than Group 1d (P = 0.028 and P = 0.036, respectively). Among the entire group, SBP and DBP positively correlated with C0; Scr and SBP, with FENa. While there was a positive correlation between SBP and C0 in groups 1s and 2s (r = 0.188, P <.000; and r = 0.145, P =.040), DBP was only associated with C0 in group 1d (P =.03, r = 0.156). In contrast, DBP showed a positive correlation with Scr in group 2d (P =.023, r = 0.132), and SBP with Scr in Group 1s. C0 and Scr levels were correlated in Groups 1s, 1d and 2d. At high BP levels (>95p), SBP is mostly affected by C0; DBP, with Scr. However, in both groups these two parameters positively correlate with each other. Thus, in adolescent renal transplant recipients the cause of high blood pressure does not appear to be solely related to cyclosporine related to induced allograft dysfunction.

Ambulatory blood pressure monitoring in renal transplantation: should ABPM be routinely performed in renal transplant patients?

In renal transplant recipients, hypertension is common and associated with increased cardiovascular and allograft rejection risks. Ambulatory blood pressure monitoring is required for its accurate diagnosis and adequate treatment, as it clearly offers several advantages over office or casual blood pressure measurements. First, it correlates better with target-organ damage and with cardiovascular mortality. Second, ambulatory blood pressure monitoring can eliminate "white coat" hypertension. Most important is the identification of nocturnal hypertension, an independent cardiovascular risk factor. A circadian nondipping pattern is often found in renal transplant recipients, most probably resulting from cyclosporine A and persistent fluid overload in the early posttransplant phase (approximately 70% prevalence), but reflecting an underlying renal (parenchymal or vascular) allograft disease when persistent (approximately 25% prevalence) beyond the first year posttransplant.

24-Hour BP in Children With Congenital Central Hypoventilation Syndrome

OBJECTIVE

To study circadian BP patterns in patients with congenital central hypoventilation syndrome (CCHS).

DESIGN

Case-control study.

SETTING

Teaching hospital in Paris, France.

PATIENTS

Eleven patients with CCHS (median age, 13 years; range, 6 to 18 years) and 11 sex- and height-matched control subjects.

INTERVENTION

None.

METHODS

Each subject underwent 24-h ambulatory BP monitoring. Oxygen saturation and end-tidal PCO(2) were monitored noninvasively. Polysomnography was performed to determine sleep times. All patients with CCHS received mechanical ventilation during sleep. Mean values for systolic BP (SBP) and diastolic BP (DBP) during wakefulness and sleep were analyzed. Nocturnal BP "dipping" was defined as the difference in mean SBP (and/or DBP) between wakefulness and sleep, divided by individual waking mean values. BP "dippers" were defined as subjects showing at least 10% nocturnal dipping.

RESULTS

Patients with CCHS had BPs in the low normal range of normative data. As compared to control subjects, patients with CCHS had lower BP during wakefulness (p = 0.003 and p = 0.016 for SBP and DBP, respectively), and higher BP during sleep (p = 0.016 and p = 0.002). Nocturnal BP dipping was abnormally reduced in patients with CCHS (p = 0.000). Ten of the 11 patients with CCHS were BP nondippers, compared to none of the control subjects.

CONCLUSION

The abnormal circadian BP pattern observed in children and adolescents with CCHS may be related to autonomic nervous dysfunction. Lifelong cardiovascular follow-up is recommended for patients with CCHS.

Ambulatory blood pressure monitoring in pediatric renal transplantation

Over last two decades ABPM has evolved from a research device to an established and valuable clinical tool for BP evaluation. More than 10 yrs ago ABPM was introduced to pediatrics and since that time, its importance has been increasing in the management of hypertension in children and adolescents. This review summarizes the information gathered from the studies of ABPM in adult and pediatric patients with renal transplants. We will review the importance of hypertension in this patient subset, discuss the advantage of ABPM over CBP and focus on specific abnormalities and clinical significance of ABPM in renal transplant recipients.

Reflux nephropathy and hypertension: correlation with the progression of renal damage

The aim of this study was to evaluate the relationship between blood pressure (BP), measured with ambulatory blood pressure monitoring (ABPM), and the progression of renal damage in 100 (70 females, 30 males) normotensive children with reflux nephropathy (RN). The patients, mean age of 13.5+/-5 years and almost 5 years of follow-up, were divided according to degree of RN into group A (I/II) and group B (III/IV). For each subject, 24-h systolic and diastolic BP (SBP-DBP), load (percentage of BP readings that exceeded the age- and sex-specific 95th percentile), and biochemical parameters were recorded. There was no significant difference in casual BP between the groups. The mean 24-h SBP-DBP and load were significantly higher in group B than A. There was a significant difference in creatinine (Cr) levels between the groups, and Cr correlated with BP in both groups. In group B, microalbuminuria correlated with ambulatory BP, and plasma renin activity failed to decrease with chronological age. Elevated load was shown in 8 of 50 patients in group A and in 21 of 50 in group B. In 3 of 12 patients of group B, with increased load BP, left ventricular geometry, by integrated backscatter, was abnormal. ABPM was useful in selected children at risk of hypertension.

Office and ambulatory blood pressure elevation in children with chronic renal failure

Hypertension is a frequent complication in patients with chronic renal insufficiency (CRI) and is associated with target organ damage, including left ventricular hypertrophy (LVH). To better assess hypertension in pediatric patients with CRI, we performed 24-h ambulatory blood pressure monitoring (ABPM) and evaluated the relationship between ABPM parameters and LVH in 29 children, mean age 12.4+/-3.8 years. There was no significant difference in the frequency of hypertension comparing casual systolic blood pressure (SBP) (21%) with the mean 24-h (21%) or daytime mean SBP (21%). However, diastolic hypertension was detected more frequently using ABPM: 24% for 24-h diastolic blood pressure (DBP), 14% for daytime DBP, and 7% for casual DBP. Nighttime systolic hypertension as well as diastolic hypertension was detected in 12 (41%) children. Seventeen (59%) patients had attenuated dipping for SBP and 9 (31%) had abnormal DBP dipping. Lower SBP dipping was associated with lower glomerular filtration rate (r=0.44, P<0.05). LVH was found in 6 (21%) patients. LVM index was significantly correlated with 24-h SBP (r=0.43, P<0.05). Multiple regression analysis confirmed that higher 24-h SBP was the only independent predictor for increased LVM index (P=0.001). No significant relationship was found between LVM index and office blood pressure. These results confirm a high prevalence of blood pressure abnormalities using ABPM criteria in children with CRI and suggest that ABP may better predict end-organ damage in these patients than casual BP.

Ambulatory blood pressure monitoring in children and adolescents

With recent technological advances, 24-hour ambulatory blood pressure (BP) monitoring (ABPM) has become a useful tool for the evaluation, diagnosis, and management of hypertensive children. It provides a more accurate representation of an individual's BP rather than intermittent casual or office BP measurements. Hence, ABPM is being used more often to assess the BP of children. In this comprehensive review, we provide the reader with the available literature on ABPM, discuss the advantages and limitations of ABPM, and the interpretation of ABPM data. The role of ABPM in various clinical conditions and hypertension research in children is presented.

Ambulatory blood pressure monitoring in chronic renal disease: technical aspects and clinical relevance

PURPOSE OF REVIEW

To evaluate the current value of ambulatory blood pressure monitoring in patients with chronic renal disease and end-stage renal disease.

RECENT FINDINGS

Ambulatory blood pressure monitoring has become an important tool in hypertension research and clinical practice. Its use in essential hypertension shows a strong predictive ability in the assessment of cardiovascular outcomes. In chronic renal failure and end-stage renal disease, the role of ambulatory blood pressure monitoring is still being actively evaluated, and available evidence shows that it is better than office blood pressure in predicting left ventricular hypertrophy and progression of renal dysfunction in patients with chronic renal failure. In end-stage renal disease, preliminary data suggest better prediction of mortality in hemodialysis patients in comparison with clinic blood pressures. The most conspicuous problems with the literature on this subject are small sample sizes and the paucity of longitudinal observational studies and intervention trials.

SUMMARY

Preliminary data and extrapolations from essential hypertension have justified a growing excitement about the use of ambulatory blood pressure monitoring in renal disease. However, further research will have to address the limitations of the available literature before generalization of its use is implemented.

Pediatric hypertension 2001

During the past decade, there has been a surge of interest in childhood and adolescent hypertension. The current review summarizes work published during the past year in the following areas: prenatal and early postnatal causes of hypertension; new information on the genetics of childhood hypertension; the relation of obesity, insulin resistance, and diabetes to hypertension; the use of ambulatory blood pressure monitoring to evaluate childhood hypertension; and advances in drug therapy for children with hypertension. The information obtained during the past year has improved our understanding of the pathogenesis, diagnosis, and treatment of childhood hypertension.