Usefulness of ambulatory blood pressure monitoring in diagnosis of arterial hypertension in children and adolescents

BACKGROUND: Arterial hypertension in children and adolescents is an important medical problem with a prevalence rising over the last ten years from 1 to 4.5%. AIM: To assess the usefulness of ambulatory blood pressure monitoring (ABPM) in diagnosis of arterial hypertension in children and adolescents. METHODS: Two hundred and twelve children with elevated blood pressure (BP) and 81 healthy controls participated in this study. In all children from the study and control groups standard BP measurement and ABPM were performed. RESULTS: With the use of standard BP measurement, 168 (79.2%) children were diagnosed as hypertensive and the remaining 44 (20.8%) as prehypertensive. When the ABPM was used, arterial hypertension was diagnosed in 143 (67.4%) cases and white coat hypertension in the remaining 69 (32.6%) subjects. In 7 (8.7%) control children elevated BP in ABPM was detected, and masked hypertension were diagnosed. CONCLUSIONS: 1. Ambulatory blood pressure monitoring is a useful tool in diagnosis of arterial hypertension in children and adolescents. 2. Systolic hypertension is a major form of hypertension in childhood. 3. Ambulatory blood pressure monitoring is helpful to identify patients with white coat hypertension. 4. Further studies are necessary to establish uniform indications, standards and rules for interpretation of ABPM in children and adolescents.     

Diagnosis of hypertension in children and adolescents based on home versus ambulatory blood pressure monitoring

OBJECTIVE: To investigate the usefulness of home blood pressure measurements in comparison with ambulatory monitoring in the diagnosis of sustained, white-coat hypertension and masked hypertension in children and adolescents. SUBJECTS AND METHODS: One hundred and two subjects, referred for elevated blood pressure, were assessed with clinic (two visits), home (6 days) and awake ambulatory blood pressure measurements [64 boys, mean age 12.8 +/- 2.9 (SD) years, range 6-18 years]. RESULTS: Office hypertension was diagnosed in 38 subjects, ambulatory hypertension in 31 and home hypertension in 23 (P = 0.07). On the basis of clinic and ambulatory blood pressure, 52% of subjects were normotensive, 20% hypertensive, 18% had white-coat hypertension and 11% masked hypertension, whereas on the basis of clinic and home blood pressure, 55, 15, 23 and 8%, respectively. There was an agreement between ambulatory and home blood pressure in the diagnosis of hypertension in 82 cases (80%). When a 5-mmHg gray zone of diagnostic uncertainty was applied above and below the diagnostic thresholds, there were only eight cases with clinically important disagreement. By taking ambulatory blood pressure as the reference method for the diagnosis of hypertension, the sensitivity, specificity and positive and negative predictive values of home blood pressure were 55, 92, 74 and 82%, respectively, for the diagnosis of white-coat hypertension 89, 92, 70 and 98%, respectively, and for masked hypertension 36, 96, 50 and 93%, respectively. CONCLUSION: In children and adolescents, there is a reasonable agreement between home and ambulatory blood pressure measurements as diagnostic methods in hypertension. Home blood pressure appears to be a useful diagnostic test in this population, particularly for the detection of white-coat hypertension.     

Reproducibility of home and ambulatory blood pressure in children and adolescents

OBJECTIVE: To evaluate the reproducibility of blood pressure measured at home (HBP) in comparison with ambulatory (ABP) and clinic blood pressure (CBP) in children and adolescents. PARTICIPANTS AND METHODS: Individuals aged 8-17 years who had been referred for elevated CBP were included. CBP was measured at two visits, HBP on 5 days and ABP for 24 h. A second session including all the above measurements was performed after 8 weeks. The reproducibility of CBP (second visit of each session), HBP (average of days 2-5 of each session) and ABP (average 24-h, awake and asleep) was quantified using test-retest correlations coefficients (r) and the standard deviation of differences (SDD) between repeated measurements. RESULTS: Sixteen individuals were included [mean age 13.3+/-2.9 (SD)] years, range 8-17, nine boys]. According to Task Force CBP criteria, eight were classified as hypertensives, three as high normal and five as normotensives. The reproducibility of HBP (systolic/diastolic r, 0.74/0.82, SDD 7.0/4.3) was superior to that of CBP (r, 0.63/0.80, SDD 10.4/6.3). However, ABP appeared to provide the most reproducible values (r, 0.87/0.84, SDD 5.5/4.3 for 24-h ABP; r, 0.85/0.76, SDD 5.9/5.0 for awake; r, 0.76/0.79, SDD 7.0/5.0 for asleep ABP). Aspects of the diurnal ABP variation were poorly reproducible (r, 0.62/0.14, SDD 6.8/5.5 for awake-asleep ABP difference; r, 0.55/0.26, SDD 0.07/0.11 for awake : asleep ratio). CONCLUSION: These data suggest that in children and adolescents home blood pressure measurements are more reproducible than clinic measurements. However, 24-h ambulatory monitoring appears to provide the most reproducible blood pressure values.     

Out-of-office blood pressure in children and adolescents: disparate findings by using home or ambulatory monitoring

BACKGROUND: The validity of home blood pressure (HBP) measurements in children has not been evaluated, although in clinical practice such measurements are being used. This study compares HBP, with clinic (CBP) and daytime ambulatory blood pressure (ABP) in children and adolescents. METHODS: Fifty-five children and adolescents aged 6 to 18 years were evaluated with CBP (three visits), HBP (6 days), and daytime ABP. Mean age was 12.3 +/- 2.9 (SD) years, 33 boys. According to the Task Force CBP criteria, 26 were hypertensives, 6 had high-normal BP (hypertensive group), and 23 were normotensives (normotensive group). RESULTS: In the hypertensive group, CBP was 130.8 +/- 7.6/72.5 +/- 8.1 mm Hg (systolic/diastolic), HBP 118.9 +/- 6.3/73.7 +/- 6.7, and ABP 130.8 +/- 8.1/75.5 +/- 8.3. In the normotensive group, CBP was 112.8 +/- 8/63.1 +/- 6.3, HBP 106.7 +/- 8.4/67.2 +/- 5.2, and ABP 123.9 +/- 7.2/72 +/- 4.3. Strong correlations (P < .001) were observed between CBP-HBP (r = 0.73/0.57, systolic/diastolic), CBP-ABP (r = 0.59/0.49), and HBP-ABP (r = 0.72/0.66). In normotensive subjects, ABP was higher than both CBP and HBP for systolic and diastolic BP (P < .001). Furthermore, systolic HBP was lower than CBP (P < .01), whereas the opposite was true for diastolic BP (P < .05). In hypertensive subjects systolic HBP was lower than both CBP and ABP (P < .001), whereas CBP did not differ from ABP. For diastolic BP no differences were found among measurement methods. CONCLUSIONS: These data suggest that, in contrast to adults in whom HBP is close to the levels of daytime ABP, in children and adolescents HBP appears to be significantly lower than daytime ABP. Until more data become available, caution is needed in the interpretation of HBP in children and adolescents.     

Comparison between casual blood pressure and ambulatory blood pressure monitoring parameters in healthy and hypertensive adolescents

Casual blood pressure measurements were compared with mean ambulatory blood pressure values during wakefulness and sleep in 45 normotensive and 30 hypertensive adolescents of both sexes aged 10-18 years. Two sets of auscultatory casual blood pressure were obtained, one in a pediatric office setting (office blood pressure), performed by the physician, and one in the ambulatory blood pressure monitoring (ABPM) unit, performed by a trained nurse, prior to the initiation of ABPM (pre-ABPM blood pressure). In normotensive and hypertensive subjects of both sexes, the mean office systolic blood pressure (SBP) was lower than the mean pre-ABPM SBP, and the mean office diastolic blood pressure (DBP) was lower than the mean pre-ABPM DBP. In normotensive participants, the mean pre-ABPM SBP/DBP was lower than the mean ABPM SBP/DBP while awake, the mean ABPM SBP/DBP during sleep being lower than the mean ABPM SBP/DBP values while awake and the mean pre-ABPM SBP/DBP. No statistical difference was demonstrated between the mean office SBP and the mean ABPM SBP during sleep, the mean ABPM DBP during sleep being lower than the mean office DBP. The hypertensive adolescents presented a blood pressure profile similar to that of the normotensive group, albeit shifted upwards, with no significant difference between the mean pre-ABPM SBP and the mean ABPM SBP while awake but a higher mean pre-ABPM DBP than mean ABPM DBP while awake. This study suggests that, by evaluating the casual blood pressure in different environment/observer situations, the power of casual blood pressure to predict inadequate blood pressure control, manifested as abnormal ABPM parameters, can be enhanced. Our data indicate ABPM to be the method of choice for the early diagnosis and adequate follow-up of adolescent hypertension.     

Diagnosis of high blood pressure in children by means of ambulatory blood pressure monitoring

Conclusions In conclusion, ambulatory BP monitoring has become a useful tool for the proper assessment of hypertension and should be performed as part of the initial evaluation in older children with persistent mild hypertension. The accurate diagnosis of whether or not hypertension is present in children may both prevent unnecessary diagnostic evaluation as well as allow early intervention so as to prevent the development of persistent hypertension and its sequelae.     

Relationship between ambulatory blood pressure monitoring and response of blood pressure in male hypertensive adolescents to exercise

BACKGROUND: High blood pressure in the young has been related to the development of hypertension in adults; hence the importance of identifying adolescents with the risk of developing it.OBJECTIVE: To investigate the relationship between 24 h ambulatory blood pressure monitoring and the response of blood pressure in adolescents to exercise. DESIGN: A prospective and cross-sectional study. METHODS: We classified 101 men aged 13-18 years as obese hypertensive, lean hypertensive, obese normotensive, and lean normotensive. Mean blood pressure and variability were measured with ambulatory blood pressure monitoring, and expressed as 24 h, awake, and sleeping periods. Treadmill tests were also performed. RESULTS: Hypertensives and obese normotensives had higher ambulatory blood pressure monitoring values (P< 0.0001). Systolic blood pressure during sleep in obese subjects was significantly higher than that in lean usbjects (119.9 +/- 9 versus 113.6 +/- 8 mmHg, P < 0.001, obese hypertensives versus lean hypertensives; and 113.6 +/- 2 versus 103.0 +/- 2 mmHg, P < 0.002, obese normotensives versus lean normotensives) and nocturnal drop of systolic blood pressure was lower in obese subjects. We found a significant correlation between systolic blood pressure during ambulatory blood pressure monitoring and systolic blood pressure during moderate and maximal exercise for all periods (P < 0.0001). Blood pressure variability during awake period was higher in subjects with maximum exercise systolic blood pressure >/= 200 mmHg (7.4 +/- 2 versus 6.4 +/- 2%, P < 0.01).CONCLUSION: Systolic blood pressure measured by ambulatory blood pressure monitoring is related to response of systolic blood pressure to exercise and ambulatory blood pressure monitoring can identify groups of subjects at greater than normal risk through their higher blood pressure during sleep. Greater than normal blood pressure variability in adolescents is an indicator of the risk of reaching abnormal exercise values of systolic blood pressure. Higher casual blood pressure than ambulatory blood pressure monitoring values for adolescents should be considered abnormal.     

Arterial hypertension in children and adolescents after surgical repair of aortic coarctation defined by ambulatory blood pressure monitoring

BACKGROUND: Despite early operation, persistent and late systolic hypertension are common among children and adolescents after surgical repair of aortic coarctation and can contribute to early cardiovascular morbidity. METHODS: Ambulatory blood pressure monitoring was performed for 78 patients (aged 3.6-22.8 years, 41 male) after successful surgical repair of aortic coarctation (median duration of follow-up 6.5 years, range 0.7-20.1 years). Hypertension was defined as mean systolic blood pressure exceeding the 95th percentile for sex and height. RESULTS: Twenty-three patients (29%) exhibited systolic hypertension during daytime. Hypertensive patients had been older at the time of operation than had normotensive patients (5.4+/-5.0 versus 2.4+/-3.1 years, P<0.01). Prevalence of hypertension was 21% among patients who had undergone surgery during the first year of life and 38% among patients who had been operated upon later. Decline in blood pressure during night was similar for all patients (systolic 11+/-5% and diastolic 19+/-8%). Systolic hypertension during night-time was found in 24% of patients who were normotensive during day. Diastolic hypertension was rare. Follow-up measurements were performed for 41 patients after 2.3+/-1. 3 years, and most normotensive patients remained normotensive during this time. CONCLUSIONS: Ambulatory blood pressure monitoring allows one to estimate nocturnal hypertension in children and adolescents after surgical repair of aortic coarctation which is common also among normotensive patients during daytime.     

Stability of diurnal blood pressure rhythm during 48-hour ambulatory blood pressure monitoring

Evaluation of nocturnal blood pressure (BP) fall is important for prognosis and selection of antihypertensive therapy. We assessed stability of BP diurnal rhythm in 56 hospitalized hypertensive patients by means of 48-hour ambulatory BP monitoring. According to the degree of congruence of BP fall during two nights of monitoring the following groups of patients were distinguished: with similar diurnal BP rhythm in both nights (72% of all patients, including 42% with sufficient and 30% with insufficient nocturnal BP decline), with different diurnal BP rhythms - with sufficient fall of BP in one night and insufficient in another (28% of all patients). BP variability in all patients did not change and could be considered very stable. Thus when insufficient nocturnal BP fall is detected its stability should be confirmed by repeat BP monitoring.     

Population studies of ambulatory blood pressure monitoring in Brazilian children.

BACKGROUND: The determination of hypertension in a given population depends on the knowledge of population norms for blood pressure. This is true for both casual blood pressure (CBP) measurements and the newest and most promising technology of ambulatory blood pressure monitoring (ABPM). OBJECTIVE: To design an ambitious multinational co-operative study to determine normal blood pressure data in Brazilian children. METHODS: The study was designed to determine normative data for CBP, using the Task Force technical recommendations for age-, sex- and height-percentile-specific blood pressure values. The proposed procedure is as follows. ABPM will be studied in a random subgroup of individuals, to develop similar normative data. These data will be correlated to CBP measurements and to echocardiographic findings as a measure of end-organ damage. All patients who are diagnosed by CBP measurement to be hypertensive will also be studied by ABPM, and studies of target-organ damage will be performed. Family and medical histories will be evaluated by questionnaire and first-degree relatives will be evaluated for CBP measurement. Hypertensive patients will form a cohort for long-term follow-up. These data will be the foundation for studies of hypertension in Brazilian children.     

Accuracy of the SpaceLabs 90207 ambulatory blood pressure monitor in children and adolescents

OBJECTIVE: To determine the accuracy of the SpaceLabs 90207 ambulatory blood pressure monitor for measurement of systolic and Korotkoff phases IV and V diastolic blood pressures in children aged 6-18 years. DESIGN: Monitor evaluation was performed using the 1990 British Hypertension Society (BHS) protocol, adapted for use in children. METHODS: Three SpaceLabs 90207 monitors were evaluated according to the five phases of the 1990 BHS protocol: observer training and assessment; before-use interdevice variability assessment; in-use (field) assessment; after-use interdevice variability assessment; and device validation. Outcome was classified according to the criteria from the BHS (1990) and Association for the Advancement of Medical Instrumentation (AAMI) protocols. RESULTS: During in-use assessment, the monitor failed to achieve the required 70% valid readings on four of 25 recording days. On three of four failed days, kinked tubing errors were noted, possibly caused by excess tubing length. After adjustment of tubing length to body size, criteria were satisfied on 24 additional recording days. During validation, the monitor achieved BHS grade C for systolic blood pressure and satisfied AAMI criteria with a mean difference of 5.0+/- 6.4 mmHg. The monitor received grade D for Korotkoff phase IV and V diastolic blood pressure and failed to satisfy AAMI criteria with a mean difference of -7.2+/- 11.0 mmHg for Korotkoff phase IV and 0.8+/-11.1 mmHg for Korotkoff phase V. CONCLUSION: The SpaceLabs 90207 monitor satisfied the minimum accuracy criteria for measurement of systolic, but not diastolic, blood pressure in children aged 6-18 years.     

Reproducibility of ambulatory blood pressure monitoring

Short-term blood pressure variability has been studied extensively with monitoring techniques. To assess whether or not and to what extent average 24-hour blood pressure varies when repeatedly recorded, 12 mild to moderate hypertensive subjects underwent 3 non-invasive blood pressure monitorings at monthly intervals. When the average 24-hour blood pressure of the whole group was evaluated no substantial differences were found between the 3 recordings, even though slightly lower blood pressure values were recorded at the first monitoring. However, when the within-period comparison was studied in the single patients, remarkable discrepancies of up to 20.9/15.8 mmHg were detected. Systolic and diastolic blood pressure variations greater than or equal to 5 mmHg were recorded in 58% of the subjects. These differences were unrelated to the number of faulty readings. Casual blood pressure varied even to a greater extent between the first and the subsequent visits; no correlation was found between casual and 24-hour blood pressure variations. The results of the present study indicate that ambulatory blood pressure may vary even to a great extent when repeatedly recorded. This finding entails important clinical implications, as the evaluation of the hypertensive patient is usually made with a single blood pressure monitoring.     

Sleep disturbance during ambulatory blood pressure monitoring of hypertensive patients

BACKGROUND: Hypertensive patients who fail to exhibit a normal fall in blood pressure at night may have a greater risk of target-organ damage. Sleep, with associated cessation of physical activity, is the principal determinant of nocturnal blood pressure 'dip'. OBJECTIVE: To ascertain whether hypertensive patients, who experience the discomfort of higher cuff-inflation pressures during ambulatory blood pressure monitoring, experience more interference with sleep, manifested by greater nocturnal physical activity. DESIGN: A retrospective case- control study. METHODS: Subjects were selected from a database of 475 patients who had undergone simultaneous 24 h ambulatory blood pressure monitoring and monitoring of physical activity with a wrist-mounted piezoelectric accelerometer. Sixty-one hypertensives (average daytime systolic blood pressure >/= 150 mmHg) were age matched to 61 subjects with average daytime systolic blood pressures 相似文献   

Reliability of ambulatory blood pressure monitoring

OBJECTIVE: To focus on the reliability of ambulatory blood pressure monitoring and on its limitations in clinical practice, and to construct adequate strategies to improve ambulatory monitoring performance. METHODS: The literature was reviewed, and personal data were used. DISCUSSION: Since the beginning of non-invasive ambulatory blood pressure monitoring, it appeared that some subjects had a high proportion of outlying readings that were unlikely to be accurate. Although ambulatory blood pressure is more reproducible than clinic blood pressure, large day-to-day differences have also been reported in reproducibility studies for average 24 h blood pressure. It has been shown that, for day-to-day 24 h blood pressure differences greater than 4/3 mmHg, ambulatory blood pressure is poorly predictive of the degree of target organ damage. The variability of average 24 h blood pressure may arise from several causes, including true biological variability, a lack of standardization of activities and measurement errors. Artefactual readings can easily occur if patients are not properly instructed. Although editing procedures can eliminate outliers, it is often impossible to identify inaccurate readings included within the patient's trend. To optimize ambulatory blood pressure monitoring, health-care providers should be instructed adequately on how to perform this technique. Appropriate patient selection, a proper application of instrumentation and the checking of its performance, careful instructions to patients, the immediate evaluation of the patient's diary and 24 h tracing after completion of the recording should improve the results of ambulatory monitoring. CONCLUSIONS: A checklist of criteria that should be used for optimizing ambulatory monitoring in clinical practice should be proposed by the Consensus Conference on ambulatory blood pressure monitoring. To improve doctors' proficiency, strategies including educational protocols and training programmes should be implemented.     

Epidemiology of ambulatory blood pressure monitoring

An operational threshold for making clinical decisions on the basis of ambulatory blood pressure monitoring must be defined [1-3]. This requires that the relationship between the ambulatory blood pressure and the incidence of cardiovascular complications be clarified beyond present understanding [4-7]. In addition, the distribution of the ambulatory blood pressure must be characterized better under various conditions and for various populations and compared with the centrality and spread of the conventional blood pressure under similar circumstances.