Association of clinic and ambulatory blood pressure with vascular damage in the elderly: the EPICARDIAN study

The Role of Blood Pressure Load in Ambulatory Blood Pressure Monitoring in Adults: A Literature Review of Current Evidence

BACKGROUND

The blood pressure load (BPL) is commonly defined as the percentage of readings in a 24-h ambulatory blood pressure monitoring (ABPM) study above a certain threshold, usually the upper normal limit. While it has been studied since the 1990s, the benefits of using this index have not been clearly demonstrated in adults. We present the first review on the associations of BPL with target organ damage (TOD) and clinical outcomes in adults, the major determinants for its role and utility in blood pressure measurement. We emphasize studies which evaluated whether BPL has added benefit to the average blood pressure indices on ABPM in predicting adverse outcomes.

METHODS

PubMed search for all English language papers mentioning ABPM and BPL.

RESULTS

While multiple studies assessed this question, the cumulative sample size is small. Whereas the associations of BPL with various TODs are evident, the available literature fails to demonstrate a clear and consistent added value for the BPL over the average blood pressure indices.

CONCLUSIONS

There is a need for prospective studies evaluating the role of BPL in blood pressure measurement. The current literature does not provide sound support for the use of BPL in clinical decisions.

Ten-year changes in ambulatory blood pressure: The prognostic value of ambulatory pulse pressure

Blood pressure (BP) changes and risk factors associated with pulse pressure (PP) increase in elderly people have rarely been studied using ambulatory blood pressure monitoring (ABPM). The aim is to evaluate 10-year ambulatory blood pressure (ABP) changes in older hypertensives, focusing on PP and its associations with mortality. An observational study was conducted on 119 consecutive older treated hypertensives evaluated at baseline (T0) and after 10 years (T1). Treatment adherence was carefully assessed. The authors considered clinical parameters at T1 only in survivors (n = 87). Patients with controlled ABP both at T0 and T1 were considered as having sustained BP control. Change in 24-hour PP between T0 and T1 (Δ24-hour PP) was considered for the analyses. Mean age at T0: 69.4 ± 3.7 years. Females: 57.5%. Significant decrease in 24-hour, daytime, and nighttime diastolic BP (all P < .05) coupled with an increase in 24-hour, daytime, and nighttime PP (all P < .05) were observed at T1. Sustained daytime BP control was associated with lower 24-hour PP increase than nonsustained daytime BP control (+2.23 ± 9.36 vs +7.79 ± 8.64 mm Hg; P = .037). The association between sustained daytime BP control and Δ24-hour PP remained significant even after adjusting for age, sex, and 24-hour PP at T0 (β=0.39; P = .035). Both 24-hour systolic BP and 24-hour PP at T0 predicted mortality (adjusted HR 1.07, P = .001; adjusted HR 1.25, P < .001, respectively). After ROC comparison (P = .001), 24-hour PP better predicted mortality than 24-hour systolic BP. The data confirm how ABP control affects vascular aging leading to PP increase. Both ambulatory PP and systolic BP rather than diastolic BP predict mortality in older treated hypertensives.

Sources of inaccuracy in the measurement of adult patients' resting blood pressure in clinical settings: a systematic review

BACKGROUND

To interpret blood pressure (BP) data appropriately, healthcare providers need to be knowledgeable of the factors that can potentially impact the accuracy of BP measurement and contribute to variability between measurements.

METHODS

A systematic review of studies quantifying BP measurement inaccuracy. Medline and CINAHL databases were searched for empirical articles and systematic reviews published up to June 2015. Empirical articles were included if they reported a study that was relevant to the measurement of adult patients' resting BP at the upper arm in a clinical setting (e.g. ward or office); identified a specific source of inaccuracy; and quantified its effect. Reference lists and reviews were searched for additional articles.

RESULTS

A total of 328 empirical studies were included. They investigated 29 potential sources of inaccuracy, categorized as relating to the patient, device, procedure or observer. Significant directional effects were found for 27; however, for some, the effects were inconsistent in direction. Compared with true resting BP, significant effects of individual sources ranged from -23.6 to +33 mmHg SBP and -14 to +23 mmHg DBP.

CONCLUSION

A single BP value outside the expected range should be interpreted with caution and not taken as a definitive indicator of clinical deterioration. Where a measurement is abnormally high or low, further measurements should be taken and averaged. Wherever possible, BP values should be recorded graphically within ranges. This may reduce the impact of sources of inaccuracy and reduce the scope for misinterpretations based on small, likely erroneous or misleading, changes.

Differing pattern of ambulatory blood pressure in very elderly men expresses dynamics in atherosclerotic load in the senescence

To assess an impact of vascular risk factors on ambulatory blood pressure measurement (ABPM) in the elderly, we followed up a population-based cohort of men from 68 until 82 years, when 104 survivors underwent ABPM. Results. At age 68, hypertension and high clinic blood pressure (CBP) did not predict ABPM level. Smoking and low ankle-brachial index (ABI) predicted higher ABPM variability and pulse pressure (PP), but not absolute ABPM values. At age 82, hypertension, high or increasing CBP, strongly positively correlated with all variables of ABPM. Carotid stenosis, low or declining ABI during followup, correlated with higher nocturnal ABPM and PP. Concluding. Hypertension and vascular risk factors in a cohort of 68-year-old men do not result in higher ABPM at age 82, possibly due to inflection point in their pressure development. Higher ABPM reflects instead an increasing CBP and aggravating atherosclerosis during the preceding decade in that part of the cohort with previously favorable risk factor status.

Age and the difference between awake ambulatory blood pressure and office blood pressure: a meta-analysis

BACKGROUND

Ambulatory blood pressure (BP) (ABP) is a better predictor of adverse cardiovascular events than office BP (OBP). Owing to the extensive literature on the 'white coat effect', it is widely believed that ABP tends to be lower than OBP, with statements to this effect in Joint National Committee VII. However, recent evidence suggests that the difference varies systematically with age.

METHODS

We searched PubMed to identify population studies, published before April 2009, which assessed OBP and either ABP or home BP (HBP). On account of significant heterogeneity in the outcomes, random effect models were used for the meta-analyses.

RESULTS

OBP increased with age more steeply than awake ABP. OBP became higher than awake systolic/diastolic ABP at the age of 51.3/42.7 years in men (13 studies, N=3562) and 51.9/42.3 years in women (11 studies, N=2585). In the data in which OBP and HBP were measured (eight studies, N=4916), OBP was higher than HBP at all ages. In the data in which OBP, awake ABP, and HBP were all measured (two studies, N=895), awake ABP was higher than HBP at younger ages, becoming similar at the older age.

CONCLUSION

OBP tends to be higher than awake ABP only after the age of 50 years for systolic and after the age of 45 years for diastolic BP, but is lower than ABP at younger ages; in contrast OBP tends to exceed HBP at all ages.