Ambulatory blood pressure monitoring and postprandial hypotension in elderly patients with isolated systolic hypertension. Systolic Hypertension in Europe (SYST-EUR) Trial Investigators

Association between hypotension during 24 h ambulatory blood pressure monitoring and reflex syncope: the SynABPM 1 study

AIMS

Diagnostic criteria for ambulatory blood pressure monitoring (ABPM) in patients with suspected reflex syncope are lacking. The study hypothesis was that patients with reflex syncope have a higher prevalence of systolic blood pressure (SBP) drops on ABPM.

METHODS AND RESULTS

ABPM data from reflex syncope patients and controls, matched by average 24 h SBP, age, sex, and hypertension were compared. Patients with constitutional hypotension, orthostatic hypotension, and predominant cardioinhibition during carotid sinus massage or prolonged electrocardiogram monitoring or competing causes of syncope were excluded. Daytime and nighttime SBP drops (<110, 100, 90, 80 mmHg) were assessed. Findings were validated in an independent sample. In the derivation sample, daytime SBP drops were significantly more common in 158 syncope patients than 329 controls. One or more daytime drops <90 mmHg achieved 91% specificity and 32% sensitivity [odds ratio (OR) 4.6, P < 0.001]. Two or more daytime drops <100 mmHg achieved 84% specificity and 40% sensitivity (OR 3.5, P = 0.001). Results were confirmed in the validation sample of 164 syncope patients and 164 controls: one or more daytime SBP drops <90 mmHg achieved 94% specificity and 29% sensitivity (OR 6.2, P < 0.001), while two or more daytime SBP drops <100 mmHg achieved 83% specificity and 35% sensitivity (OR 2.6, P < 0.001).

CONCLUSION

SBP drops during ABPM are more common in reflex syncope patients than in controls. Cut-off values that may be applied in clinical practice are defined. This study expands the current indications for ABPM to patients with reflex syncope.

Longitudinal Changes in the Blood Pressure Responses to, and Gastric Emptying of, an Oral Glucose Load in Healthy Older Subjects

The rate of gastric emptying is a major determinant of the hypotensive response to a meal. Cross-sectional studies suggest that healthy aging is associated with a modest slowing of gastric emptying. We aimed to determine longitudinal changes in the blood pressure (BP) response to, and gastric emptying of, glucose in healthy older people. Thirty-three participants (77.0 ± 0.7 years) had baseline and follow-up measurements after 5.8 ± 0.1 years. Participants consumed a 300-mL drink containing 75 g glucose and 150 mg C13-acetate. BP and heart rate (HR) were measured at 5-minute intervals for 120 minutes after the drink. Exhaled breath was collected to calculate the gastric 50% emptying time. The prevalence of postprandial hypotension (PPH) doubled from 9.1% to 18.2%. Gastric emptying was slower at follow-up (p = .04). The fall in systolic BP (SBP) was related directly to the rate of gastric emptying at both the initial study (r = .54, p = .005) and at follow-up (r = .41, p = .04). The change in the maximum fall in SBP was related to the increase in baseline SBP (r = -.63, p < .001). In conclusion, in healthy older people over a period of ~5.8 years, there was an increased prevalence of PPH and a modest slowing of gastric emptying. The latter was related directly to a greater hypotensive response.

Orthostatic Intolerance in Older Persons: Etiology and Countermeasures

Orthostatic challenge produced by upright posture may lead to syncope if the cardiovascular system is unable to maintain adequate brain perfusion. This review outlines orthostatic intolerance related to the aging process, long-term bedrest confinement, drugs, and disease. Aging-associated illness or injury due to falls often leads to hospitalization. Older patients spend up to 83% of hospital admission lying in bed and thus the consequences of bedrest confinement such as physiological deconditioning, functional decline, and orthostatic intolerance represent a central challenge in the care of the vulnerable older population. This review examines current scientific knowledge regarding orthostatic intolerance and how it comes about and provides a framework for understanding of (patho-) physiological concepts of cardiovascular (in-) stability in ambulatory and bedrest confined senior citizens as well as in individuals with disease conditions [e.g., orthostatic intolerance in patients with diabetes mellitus, multiple sclerosis, Parkinson's, spinal cord injury (SCI)] or those on multiple medications (polypharmacy). Understanding these aspects, along with cardio-postural interactions, is particularly important as blood pressure destabilization leading to orthostatic intolerance affects 3-4% of the general population, and in 4 out of 10 cases the exact cause remains elusive. Reviewed also are countermeasures to orthostatic intolerance such as exercise, water drinking, mental arithmetic, cognitive training, and respiration training in SCI patients. We speculate that optimally applied countermeasures such as mental challenge maintain sympathetic activity, and improve venous return, stroke volume, and consequently, blood pressure during upright standing. Finally, this paper emphasizes the importance of an active life style in old age and why early re-mobilization following bedrest confinement or bedrest is crucial in preventing orthostatic intolerance, falls and falls-related injuries in older persons.

Utility of home blood pressure monitoring to evaluate postprandial blood pressure in treated hypertensive patients

Postprandial hypotension, defined as a fall in systolic blood pressure (SBP) of 20 mmHg or greater within 2 hours after a meal, is a risk factor for stroke, coronary events and mortality. The clinical suspicion is typically raised by episodes of postprandial syncope or falls, whereas asymptomatic postprandial hypotension is mostly neglected. The magnitude of the postprandial fall in SBP, as detected by 24-hour recording in apparently healthy middle-aged to elderly subjects, was proportional to the severity of the silent cerebrovascular damage. Postprandial hypotension can also be detected by self-measured blood pressure before and within 2 hours after meals using automatic devices. The review highlights the value of home blood pressure monitoring (HBPM) as a screening test for asymptomatic postprandial hypotension in hypertensive patients. Using a HBPM protocol that included duplicated blood pressure measurements before and after three consecutive lunches, we detected unsuspected postprandial hypotension in 27.4% of the 230 hypertensive patients screened. The prevalence of postprandial hypotension was 13.2% in controlled and 42.2% in uncontrolled hypertensive patients (p < 0.001), raising the dilemma of further lowering blood pressure in the setting of postprandial hypotension. The inclusion of preprandial and postprandial measurements in the protocol of HBPM is useful to identify hypertensive patients with postprandial hypotension and may guide adjustments in antihypertensive treatment according to postprandial blood pressure.

Postprandial hypotension: a systematic review

BACKGROUND

Postprandial hypotension (PPH) is an important clinical problem, which has received inappropriately little attention.

METHODS

A systematic search of the databases PubMed, Embase, Cochrane Library, and Web of Knowledge, from their inception to the present time, was conducted to identify studies relevant to the epidemiology, pathophysiology, and/or management of PPH.

RESULTS

A total of 417 full-text papers were retrieved from database searching and, following screening, 248 were retained. Of these, 167 papers were considered eligible for inclusion.

CONCLUSIONS

PPH occurs commonly in older people and represents a major cause of morbidity. Although the pathophysiology of PPH remains poorly defined, diverse factors, including impairments in sympathetic and baroreflex function, release of vasodilatory peptides, the rate of small intestinal nutrient delivery, gastric distension, and splanchnic blood pooling, appear important. Current pharmacologic and nonpharmacologic management is suboptimal. Research into the pathophysiology of PPH represents a priority so that management can be targeted more effectively.

European Society of Hypertension position paper on ambulatory blood pressure monitoring

Ambulatory blood pressure monitoring (ABPM) is being used increasingly in both clinical practice and hypertension research. Although there are many guidelines that emphasize the indications for ABPM, there is no comprehensive guideline dealing with all aspects of the technique. It was agreed at a consensus meeting on ABPM in Milan in 2011 that the 34 attendees should prepare a comprehensive position paper on the scientific evidence for ABPM.This position paper considers the historical background, the advantages and limitations of ABPM, the threshold levels for practice, and the cost-effectiveness of the technique. It examines the need for selecting an appropriate device, the accuracy of devices, the additional information and indices that ABPM devices may provide, and the software requirements.At a practical level, the paper details the requirements for using ABPM in clinical practice, editing considerations, the number of measurements required, and the circumstances, such as obesity and arrhythmias, when particular care needs to be taken when using ABPM.The clinical indications for ABPM, among which white-coat phenomena, masked hypertension, and nocturnal hypertension appear to be prominent, are outlined in detail along with special considerations that apply in certain clinical circumstances, such as childhood, the elderly and pregnancy, and in cardiovascular illness, examples being stroke and chronic renal disease, and the place of home measurement of blood pressure in relation to ABPM is appraised.The role of ABPM in research circumstances, such as pharmacological trials and in the prediction of outcome in epidemiological studies is examined and finally the implementation of ABPM in practice is considered in relation to the issue of reimbursement in different countries, the provision of the technique by primary care practices, hospital clinics and pharmacies, and the growing role of registries of ABPM in many countries.

Postprandial hypotension in de novo Parkinson's disease: a comparison with orthostatic hypotension

BACKGROUND

Postprandial hypotension (PPH) is often associated with Parkinson's disease (PD). However, its mechanism remains to be fully defined. We investigated the mechanism of PPH and compared it with that of orthostatic hypotension (OH).

METHODS

The subjects were 37 patients with de novo PD and 10 healthy age-matched controls. We studied changes in blood pressure (BP), plasma norepinephrine concentrations (NE), plasma insulin, plasma glucose concentrations during a 75-g oral glucose tolerance test (75-g OGTT). Changes in BP and NE were also examined with head-up tilt-table testing (HUT).

RESULTS

The maximum fall in systolic BP (SBP) on 75-g OGTT (⊿SBPPPH) significantly correlated with that on HUT (r = 0.359, p < 0.05). On 75-g OGTT, ⊿SBPPPH significantly correlated with SBP after 20 min of rest in the supine position (r = 0.394, p < 0.01) and the time in which SBP reached its lowest (r = 0.436, p < 0.01). ⊿SBPPPH did not correlate with NE, plasma insulin and glucose concentrations after glucose loading, but significantly negatively correlated with NE measured after 20 min resting in the supine position (r = -0.347, p < 0.05). Clinical characteristics, including the presence of constipation, did not differ significantly between patients with and those without PPH.

CONCLUSIONS

In PD, systemic sympathetic denervation, impaired baroreflex-cardiovagal gain, and insufficiency of compensatory sympathetic nervous activation including lack of baroreflex-sympathoneural gain for postprandial splanchnic vessel pooling seem to be associated with PPH. Systemic sympathetic denervation and baroreflex failure seem to contribute to both pronounced morbidity and the development of PPH and OH.

Postprandial hypotension detected through home blood pressure monitoring: a frequent phenomenon in elderly hypertensive patients

Postprandial hypotension (PPH) is a frequently under-recognized entity associated with increased morbidity and mortality. The prevalence of PPH detected through home blood pressure monitoring (HBPM) is unknown. To determine the prevalence and clinical predictors of PPH in hypertensive patients assessed through HBPM. Hypertensive patients of 18 years or older underwent home blood pressure (BP) measurements (duplicate measurements for 4 days: in the morning, 1 h before and 1 h after their usual lunch, and in the evening; OMRON 705 CP). PPH was defined as a meal-induced systolic BP decrease of ≥20 mm Hg. Variables identified as relevant predictors of PPH were entered into a multivariate logistic regression analysis. In total, 230 patients were included in the analysis, with a median age of 73.6 (interquartile range 16.9) years, and 65.2% were female. The prevalence of PPH (at least one episode) was 27.4%. Four variables were independently associated with PPH: age of 80 years or older (odds ratio (OR) 3.45, 95% confidence interval (CI) 1.35-8.82), body mass index (BMI) (OR 0.88, 95%CI 0.81-0.96), office systolic BP (OR 1.03, 95%CI 1.01-1.05) and a history of cerebrovascular disease (OR 3.29, 95%CI 1.03-10.53). PPH after a typical meal is a frequent phenomenon that can be detected through HBPM. Easily measurable parameters in the office such as older age, higher systolic BP, lower BMI and a history of cerebrovascular disease may help to detect patients at risk of PPH who would benefit from HBPM.

Postprandial hypotension in clinical geriatric patients and healthy elderly: prevalence related to patient selection and diagnostic criteria

The aims of this study were to find out whether Postprandial hypotension (PPH) occurs more frequently in patients admitted to a geriatric ward than in healthy elderly individuals, what the optimal interval between blood pressure measurements is in order to diagnose PPH and how often it is associated with symptoms.The result of this study indicates that PPH is present in a high number of frail elderly, but also in a few healthy older persons. Measuring blood pressure at least every 10 minutes for 60 minutes after breakfast will adequately diagnose PPH, defined as >20 mmHg systolic fall, in most patients. However with definition of PPH as >30 mmHg systolic fall, measuring blood pressure every 10 minutes will miss PPH in one of three patients. With the latter definition of PPH the presence of postprandial complaints is not associated with the existence of PPH.

Postprandial hypotension

Postprandial hypotension is both common in geriatric patients and an important but under-recognized cause of syncope. Other populations at risk include those with Parkinson disease and autonomic failure. The mechanism is not clearly understood, but appears to be secondary to a blunted sympathetic response to a meal. This review discusses the epidemiology, risk factors, and pathophysiology of postprandial hypotension in the elderly, as well as diagnosis and treatment strategies. Diagnosis can be made based on ambulatory blood pressure monitoring and patient symptoms. Lifestyle modifications such as increased water intake before eating or substituting 6 smaller meals daily for 3 larger meals may be effective treatment options. However, data from randomized, controlled trials are limited. Increased awareness of this disease may lead to improved quality of life, decreased falls and injuries, and the avoidance of unnecessary testing.

Blood pressure and ageing

Isolated systolic hypertension, an elevation in systolic but not diastolic pressure, is the most prevalent type of hypertension in those aged 50 or over, occurring either de novo or as a development after a long period of systolic-diastolic hypertension with or without treatment. The increase in blood pressure with age is mostly associated with structural changes in the arteries and especially with large artery stiffness. It is known from various studies that rising blood pressure is associated with increased cardiovascular risk. In the elderly, the most powerful predictor of risk is increased pulse pressure due to decreased diastolic and increased systolic blood pressure. All evidence indicates that treating the elderly hypertensive patient will reduce the risk of cardiovascular events. However, there is no evidence yet for the very elderly. This population is particularly susceptible to side effects of treatments and the reduction of blood pressure, although reducing the risk of cardiovascular events such as stroke, may result in increased mortality.

Postprandial Hypotension in Long-Term Care Elderly Patients on Enteral Feeding

OBJECTIVES

To examine the prevalence and nature of postprandial hypotension (PPH) in orally fed (OF), nasogastric tube (NGT)-fed, and percutaneous endoscopic gastrostomy (PEG)-fed older people.

DESIGN

Prospective comparative study.

SETTING

Nursing and skilled nursing wards of three geriatrics hospitals.

PARTICIPANTS

Three groups (OF, PEG, NGT) of long-term care patients (50 in each cohort) were enrolled.

MEASUREMENTS

Blood pressure (BP) and heart rate measurements were obtained just before lunch and at 15-minute intervals for 90 minutes after the completion of the meal. The meals were similar in caloric content and composition.

RESULTS

PPH was evidenced in 64 (43%) patients. No significant intergroup (OF, PEG, NGT) differences were present. In 68% of PPH patients, the systolic BP (SBP) drop appeared within 30 minutes, and 70% reached their systolic nadir at 60 minutes. In 31%, the SBP drop was registered on only one measurement, whereas in 25%, the drop was detected on five to six measurements. All parameters were without notable intergroup differences.

CONCLUSION

In enterally fed elderly patients (NGT or PEG), the rate and pattern of PPH are similar and not significantly different from that observed in OF patients.

Rationale and methodology of monitoring ambulatory blood pressure and arterial compliance in the Hypertension in the Very Elderly Trial

OBJECTIVE

This article describes the rationale and methodology for the monitoring of ambulatory blood pressure and arterial compliance in hypertensive patients aged 80 years and above. This is a side project of the Hypertension in the Very Elderly Trial.

METHODS

The hypertension in the Very Elderly Trial is a multicentre, double-blind, randomized, placebo-controlled trial aiming to investigate the effect of active treatment on cardiovascular and other outcomes in hypertensive patients aged 80 years or more. Patients are randomized to placebo or active treatment starting with the diuretic indapamide and adding the angiotensin-converting enzyme inhibitor perindopril if required. This study has completed a pilot trial and the main trial is now underway. Six hundred patients will have two ABPM recordings, the first at baseline and the second a year after randomization. Arterial compliance is measured using the Q wave (electrocardiogram) to Korotkoff diastole sound interval.

RESULTS

Baseline characteristics for the first 50 patients recruited are presented.

CONCLUSION

This side project will allow the investigation of 24-h ambulatory measures of blood pressure and arterial compliance as predictors of cerebrovascular and cardiovascular events in the very elderly. The project will also allow the investigation of the blood pressure and vascular compliance profiles in the very elderly and their changes with posture. The association between these measurements and mortality and morbidity in this age group will be addressed.

Postprandial hypotension predicts all-cause mortality in older, low-level care residents

OBJECTIVES

To evaluate which indices of blood pressure (BP) homeostasis are the strongest predictors of mortality in older low-level-care residents in long-term health facilities.

DESIGN

Prospective cohort study.

SETTING

Eight long-term healthcare facilities in Canberra, Australia.

PARTICIPANTS

A total of 179 randomly selected semi-independent residents aged 65 and older (mean age+/-standard deviation 83.2+/-7.0; 80% women).

MEASUREMENTS

Baseline BP levels taken while lying, after standing for 1 and 3 minutes, and sitting before and 1 hour after meal intake were recorded, as well as demographic information, chronic medical conditions, medications, and all-cause mortality during follow-up. Postprandial hypotension (PPH) was defined as a fall in systolic BP (SBP) of 20 mmHg or more 1 hour postmeal while sitting. Orthostatic hypotension (OH) was defined as a fall in SBP of 20 mmHg or more or in diastolic BP (DBP) of 10 mmHg or more within 3 minutes of standing from a supine position. Hypertension was defined as BP greater than 160/90 mmHg at commencement of the study. Mean arterial pressure (MAP) and pulse pressure (PP) were calculated.

RESULTS

At baseline, 47% of participants had hypertension, 38% PPH, and 23% OH; PP was 70 mmHg or greater in 54%, and DBP was 65 mmHg or lower in 6%. Over 4.7 years, 97 (54%) participants died. Those who died were significantly older and more likely to have PPH (47% vs 28%) and atrial fibrillation (35% vs 17%) and a significantly greater decrease in BP after meal intake. Mortality rates in those with and without PPH were 145.0 and 98.5 per 1,000 person-years, respectively. Using multivariate Cox proportional hazards models after adjustment for age, sex, presence of atrial fibrillation, Parkinson's disease, and use of diuretics, PPH was the only BP parameter that significantly and independently predicted 4.7-year all-cause mortality (relative risk (RR)=1.79; 95% confidence interval (CI)=1.19-2.68; P=.005). Further adjustment for the presence of OH, hypertension, low resting BP, coronary artery disease, cerebrovascular disease, congestive heart failure, history of syncope, cognitive impairment, cancer, diabetes mellitus, chronic obstructive pulmonary disease, and history of smoking did not reveal any new statistically significant associations. There was a dose-response relationship between postprandial fall in SBP and mortality rates. Absolute postprandial SBP of 120 mmHg or less was also significantly associated with total mortality (RR=1.69, 95% CI=1.04-2.78; P=.04). Low DBP was also associated with increased mortality (RR=1.10, 95% CI=1.01-1.13; P=.03), although this association became nonsignificant in multivariate analysis.

CONCLUSION

In older low-level-care residents, PPH is an independent predictor of all-cause mortality with no added predictive value explained by other BP indices: OH, hypertension, PP, MAP.

The effects of drinks made from simple sugars on blood pressure in healthy older people

The objective of the research was to determine the blood pressure (BP) lowering effects in older people of 50 g carbohydrate drinks with varying carbohydrate content using a randomised, cross-over study with ten (six females) healthy older subjects (mean age 72.20 (sem 1.50) years). BP, heart rate and glucometer-derived blood glucose levels were determined at baseline and following the ingestion of equal volumes (300 ml) of water and carbohydrate drinks with varying nutrient content (glucose, sucrose and fructose). A significant decline in BP over the first 60 min was seen following glucose (systolic BP (SBP) P<0.01, diastolic BP (DBP) P<0.01, mean arterial BP (MAP) P=0.03) and sucrose (SBP P<0.01, DBP P<0.01, MAP P<0.01) ingestion, although the decrease occurred earlier after glucose than sucrose ingestion (SBP 7.33 (sem 2.19) v. 21.00 (sem 4.30) min (P=0.03) and MAP 11.22 (sem 3.10) v. 17.00 (sem 3.78) min (P=0.03)). BP increased after water ingestion (SBP P=0.04, DBP P=0.18, MAP P=0.02) but did not change after fructose ingestion (SBP P=0.36, DBP P=0.81, MAP P=0.34). Post hoc analyses revealed that the BP (SBP, DBP and MAP) decrease following glucose and sucrose ingestion were similar but significantly greater than following fructose or water ingestion. Sucrose, which is used widely (table sugar), reduces BP as much as glucose. In contrast to this, fructose ingestion causes no change in BP. Further studies are required to determine if the substitution of glucose or sucrose with fructose may be beneficial in the medical management of older people with severe symptomatic postprandial hypotension.

The association between time since last meal and blood pressure in older adults: the cardiovascular health study

OBJECTIVES

To demonstrate a postprandial hypotensive (PPH) phenomenon in older adults.

DESIGN

Observational, prospective cohort study composed of baseline and nine follow-up visits.

SETTING

Cardiovascular Health Study, an epidemiological study of risk factors for cardiovascular disease in older adults.

PARTICIPANTS

Five thousand eight hundred eighty-eight community-dwelling adults aged 65 and older.

MEASUREMENTS

Blood pressure and time since last meal were recorded synchronously at baseline and at follow-up clinic visits. Generalized estimating equations were used to estimate associations between time since last meal and blood pressure and to adjust variance estimates to account for repeated blood pressure measures within subjects across fasting times.

RESULTS

Mean systolic and diastolic blood pressures were lower in the first hour after the last meal and were progressively higher through the fourth hour after the last meal than blood pressures measured immediately after the last meal (0 hour: 133.7/68.8 mmHg; 1st hour: 130.1/66.6 mmHg; 4th hour: 136.5/71.1 mmHg). Changes were significant for systolic and diastolic measures (P <.001 for both). Exploratory analyses suggested that the systolic PPH association was more pronounced in women. Little evidence was found that the degree of systolic or diastolic PPH varied by age, race, prevalent cardiovascular disease, heart rate, ejection fraction, treated hypertension or diabetes mellitus, or body mass index.

CONCLUSION

These data support previous observations that there is a significant drop in blood pressure within 1 hour after a meal in older adults. Time since last meal may be an important factor to consider when measuring blood pressure in older adults, and perhaps national standards need to be set.

Postprandial hypotension

Postprandial hypotension is a prevalent condition in the elderly population and seems to be more common in frail elderly individuals who may be more susceptible to complications such as syncope and falls. Diagnosis is relatively easy and may be reversible in many cases. The epidemiology and pathophysiology of postprandial hypotension are not defined fully; however, a number of pathologic processes likely are involved, including abnormal sympathetic function, baroreceptor function, and vasoactive peptide release and activity. The precise relationship between symptoms and postprandial reductions in blood pressure is unclear. Blood pressure maintenance after a meal may depend on the interaction of some or all of the mechanisms outlined previously to compensate for the increase in bowel blood volume. The impairment of one or more of these mechanisms could result in inadequate compensation that leads to hypotension. If so, the presence of symptoms depends on that individual patient's ability to exercise adequate compensatory cerebral autoregulation. A hypertensive elderly patient may experience symptoms with only a small reduction in blood pressure, whereas a patient with autonomic failure may require a much larger fall in blood pressure to occur before they become symptomatic. The current definition of postprandial hypotension uses a threshold of 20 mm Hg as a cut off for diagnosis, but this may not be relevant to the presence or absence of symptoms. Further epidemiologic data are needed. Additionally, there is a lack of controlled trial evidence for the drugs that are used to treat this condition, and treatment often is carried out on a trial-and-error basis. Further research must be performed to identify the specific pathophysiology in certain patient groups, such as elderly hypertensive patients and those with autonomic failure, and to identify effective pharmacologic therapies that can be supported by randomized, placebo-controlled trials.

Ambulatory blood pressure monitoring and postprandial hypotension in elderly persons with falls or syncopes

BACKGROUND

Postprandial hypotension (PPH) is increasingly recognized as a common cause of falls and syncope in elderly persons. Noninvasive ambulatory blood pressure monitoring (ABPM) has been recommended for detecting PPH. This study investigates postprandial blood pressure (BP) changes by means of ABPM in elderly patients experiencing falls or syncopes.

METHODS

Twenty-four-hour ABPM was performed in 156 inpatients (111 women, mean age 80.4 +/- 8.1 years). Among them, 45 had been admitted for falls and 75 for syncope; 36 with no history of falls or syncope served as controls. Postprandial change in systolic blood pressure (deltaSBP) was calculated by subtracting the mean SBP within the 2 hours following the meal from the mean SBP within the 2 hours preceding the meal. PPH was defined by a deltaSBP > or = 20 mm Hg.

RESULTS

For the entire group, mean SBP decreased after the three meals. On average, the decline in SBP was greater after breakfast than after lunch or dinner, and the number of patients experiencing PPH was greater after breakfast. Average maximal deltaSBP was significantly larger in the syncope group than in the other groups ( p < .05). Moreover, the number of patients experiencing PPH was significantly higher in the syncope/fall group than in the control group (23% vs 9%; p = .03). Compared with patients without PPH, patients with PPH were more likely to have a history of diabetes mellitus (p < .01) or to use more than three different drugs daily ( p = .04), and they showed greater daytime SBP variability (p < .0001). Furthermore, there was a strong positive correlation between preprandial SBP and deltaSBP after breakfast.

CONCLUSIONS

About one out of four elderly patients with falls or syncope experiences PPH, usually after breakfast. Postprandial decline in BP contributes to BP variability. deltaSBP and preprandial SBP are positively correlated.

Modern approaches to blood pressure measurement

BACKGROUND

Blood pressure (BP) is usually measured by conventional sphygmomanometry. Although apparently simple, this procedure is fraught with many potential sources of error. This review focuses on two alternative techniques of BP measurement: ambulatory monitoring and self measurement.

REVIEW

BP values obtained by ambulatory monitoring or self measurement are characterised by high reproducibility, are not subject to digit preference or observer bias, and minimise the transient rise of the blood pressure in response to the surroundings of the clinic or the presence of the observer, the so called white coat effect. For ambulatory monitoring, the upper limits of systolic/diastolic normotension in adults include 130/80 mm Hg for the 24 hour BP and 135/85 and 120/70 mm Hg for the daytime BP and night time BP, respectively. For the the self measured BP these thresholds include 135/85 mm Hg. Automated BP measurement is most useful to identify patients with white coat hypertension. Whether or not white coat hypertension predisposes to sustained hypertension remains debated. However, outcome is better correlated with the ambulatory BP than with the conventional BP. In patients with white coat hypertension, antihypertensive drugs lower the BP in the clinic, but not the ambulatory BP, and also do not improve prognosis. Ambulatory BP monitoring is also better than conventional BP measurement in assessing the effects of treatment. Ambulatory BP monitoring is necessary to diagnose nocturnal hypertension and is especially indicated in patients with borderline hypertension, elderly patients, pregnant women, patients with treatment resistant hypertension, and also in patients with symptoms suggestive of hypotension.

CONCLUSIONS

The newer techniques of BP measurement are now well established in clinical research, for diagnosis in clinical practice, and will increasingly make their appearance in occupational and environmental medicine.