White coat hypertension diagnosed by 24-h ambulatory monitoring. Examination of 159 newly diagnosed hypertensive patients.

The study was conducted to estimate the frequency of white coat hypertension, ie, hypertension when in contact with the doctor only, in patients with newly diagnosed hypertension. We studied 159 consecutive patients (median age 47 years, 86 women) referred from primary health care to a hypertension clinic. For all patients, their general practitioner had decided to treat the hypertension pharmacologically, but the treatment had not yet begun. The blood pressure measurements reported from the referring doctors were 164.1 +/- 18.1/104.3 +/- 7.1 mm Hg (mean +/- SD). Measured at the hypertension clinic with random zero sphygmomanometer the pressures were 156.8 +/- 22.5/99.8 +/- 11.7 mm Hg. The indirectly measured day-time ambulatory blood pressures were 145.2 +/- 18.1/95.9 +/- 11.5 mm Hg. When a cut-off level of 90 mm Hg diastolic was applied, all patients were considered hypertensive by the referring doctors' measurements; the random zero office measurements regarded 18.3% of the patients as normotensive. The ambulatory measurements regarded a further 24.8% as normotensive (white coat hypertensive), whereas five patients considered normotensive by office measurements were hypertensive when evaluated by ambulatory monitoring (reverse white coat phenomenon). The difference between systolic office measurements and the daytime ambulatory blood pressures was significantly larger for female patients; age was positively correlated and weight negatively correlated to this difference. No significant difference was found for the diastolic measurements. It is concluded that white coat hypertension is present in approximately a quarter of the patients with newly diagnosed hypertension. By implementing ambulatory monitoring in clinical practice some of the overdiagnosing will possibly be avoided, but further studies on the subject are needed.

Left ventricular mass and geometry in patients with established hypertension and white coat hypertension.

This study was designed to compare the cardiac mass and geometry in white coat hypertensive patients and established hypertensive patients through the prospective comparison of office blood pressure, daytime ambulatory blood pressure, and echocardiographically determined left ventricular mass and cardiac geometry in consecutive patients. We studied 143 patients from general practice in an outpatient hypertension unit. The patients had newly diagnosed mild-to-moderate hypertension prior to the institution of pharmacological anti-hypertensive therapy. All patients had a diastolic office blood pressure above 90 mm Hg; 90 had a consistently elevated diastolic blood pressure (established hypertension), whereas 53 had an average daytime ambulatory blood pressure below 90 mm Hg (white coat hypertension). Left ventricular mass index was significantly higher in the group with established hypertension, 102.4 +/- 26.6 g/m2 (mean +/- SD) v 93.6 +/- 23.5 (P = .045). Relative wall thickness was likewise significantly higher, 0.36 +/- 0.07 v 0.33 +/- 0.06 (P = .004). There was no significant difference in left atrial dimension. In a multiple regression model the ambulatory measurements and not the office measurements were statistically significantly associated with the extent of cardiac hypertrophy. Further, 44/53 (83%) of the patients with white coat hypertension had normal left ventricular dimensions, versus only 55/90 (61%) of the patients with established hypertension (P = .033). Thus, white coat hypertensive patients display less cardiac involvement than patients with established hypertension, indicating that they should rather be treated as normotensives than as hypertensives, ie, not with pharmacological antihypertensive therapy.

Smoking related to 24-h ambulatory blood pressure and heart rate: a study in 352 normotensive Danish subjects.

This study shows the association between smoking and both office and ambulatory blood pressure. By means of stratification, a uniform number of subjects of both sexes and spanning 6 decades (aged 20 to 79 years) were recruited randomly from the local community register. A total of 352 subjects participated, including 161 smokers. Smokers (both sexes and all age groups summed), as compared with nonsmokers had statistically significant lower office blood pressure as follows (mean systolic +/- SED/mean diastolic +/- SED): (systolic and diastolic, -6.8 +/- 2.1/-3.9 +/- 1.3); day ambulatory blood pressure (diastolic, /-2.8 +/- 1.0); and night ambulatory blood pressure (systolic and diastolic, -4.2 +/- 1.8/-3.9 +/- 1.1). The intraperson variability of the day ambulatory blood pressure (as measured every 15 min) was identical for the smokers and the nonsmokers. Smokers were found to have a diminished "white coat" effect; this diminished white coat effect has not previously been described. The major white coat effect was seen in the older nonsmokers, whereas the diminished white coat effect was most pronounced in the older male smokers and in the younger female smokers. Smokers seem to have a diminished white coat effect, as well as a lower ambulatory blood pressure throughout the day (diastolic) and at night (systolic and diastolic). The similar intraperson variability found in the smokers' and nonsmokers' blood pressure further speaks for a consistently lower blood pressure in smokers as compared with nonsmokers.

24-h ambulatory blood pressure in 352 normal Danish subjects, related to age and gender.

UNLABELLED: The study was conducted to determine age and sex stratified normal values for 24-h ambulatory blood pressure. A sample of 352 healthy subjects (all white) were randomly selected from the community register and stratified by sex and age groups in decades from 20 to 79 years of age. Persons with a history of hypertension, cerebral apoplexy, diabetes, myocardial or renal disease, and who were taking blood pressure-influencing medication were excluded. Ambulatory blood pressure was recorded over 24 h, with measurements taken every 15 min from 07:00 to 22:59, and every 30 min from 23:00 to 6:59. Systolic blood pressure increased only slightly with age and was significantly higher in men than in women. The diastolic blood pressure increased only slightly with age in both sexes until the 50 to 59 years age group and declined thereafter. The diastolic blood pressure was not different for the two sexes. Both systolic and diastolic blood pressure were approximately 15% lower during the night regardless of age or sex. Ambulatory blood pressure during the daytime was on an average of 5 mm Hg lower than office blood pressure, but the mean difference between the two measurements increased with age. The variability of the difference also increased with age. IN CONCLUSION: Normal values for ambulatory blood pressure are presented in a randomly selected age- and gender-stratified population. Differences between office blood pressure and ambulatory blood pressure increased with age suggesting that the previously observed higher blood pressure seen in the elderly partly might be explained by a greater impact of white coat hypertension in older people.

[The new ambulatory non-invasive 24-hour blood pressure monitoring system, Takeda Medical TM 2420. Reliability and practical experiences]. / Nyt ambulant ikke-invasivt døgnblodtryks-monitoreringssystem Takeda Medical TM 2420. Pålidelighed og praktiske erfaringer.

Takeda TM 2420 is an automatic ambulant device for measuring blood pressure which functions by auscultation of the Korokoff sounds. During static conditions, the apparatus was investigated by means of a double stetoscope and a connecting branch with the Hawksley random zero manometer. Where 69 persons were concerned (ages 13-89 years, systolic blood pressures 85-212 mmHg, diastolic blood pressure 44-110 mmHg) a difference in the systolic blood pressure of 1.5 +/- 9.2 mm Hg were found (average +/- standard deviation) and where the diastolic blood pressure was concerned 2.8 +/- 6.3 mm Hg. Statistical comparison with the Hawksley manometer on the contralateral arm in 51 volunteers produced corresponding results. In 24-hour monitoring of 80 persons, useful results were obtained in 74. The proportion of erroneous measurements was acceptable but the apparatus was unsuitable for exercise testing on an ergometer bicycle. The quality of the cuff, the connecting tubing, the carrying strap and computer programmel should be improved but the apparatus was otherwise found to be useful for daily clinical use.

[What do we know about consultation hypertension?]. / Hvad ved vi om konsultationshypertension?

This review article examines the essential literature concerning "white coat" hypertension. It is stated that "white coat" hypertension is present in approximately 20% of patients with diagnosed mild to moderate hypertension. It is concluded that the pathophysiology of "white coat" hypertension is incompletely investigated; that the prognosis for untreated "white coat" hypertension seems fair; medical treatment being scarcely required. It is concluded further that more accurate diagnosis of mild to moderate hypertension, including the use of ambulatory blood pressure monitoring, will reduce the overall expenses by approximately million Danish crowns annually (approximately 2,000,000 pounds).

[Round-the-clock blood pressure measurements in 352 persons--a reference material]. / 24 timers ambulant blodtryk hos 352 personer--et referencemateriale.

The aim of this study was to establish reference values for 24-hour ambulatory blood pressure in a Danish population stratified for gender and age in the decades from 20 to 79 years of age. A sample of 352 persons, 179 men and 173 women randomly selected from the local community register, age 20-79 years underwent 24-h ambulatory blood pressure monitoring. For men age < 50 daytime ambulatory blood pressure (median) was 125/79 mmHg and night time was 106/65 mmHg, for women the respective pressures were 113/77 mmHg and 97/64 mmHg. For men age > or = 50 daytime ambulatory blood pressure was 133/83 mmHg and night time was 124/86 mmHg, for women the respective pressures were 122/83 mmHg and 105/65 mmHg. Presently, we can only relate cardiovascular risk to clinic blood pressure. Therefore we have calculated corresponding ambulatory blood pressure values to WHO's upper limit 160/90 mmHg for normal blood pressure in the clinic and found 154/87 mmHg for daytime and 134/74 mmHg at night. For a clinic pressure of 95 mmHg the corresponding daytime value was 91 mmHg, for 100 mmHg it was 95 mmHg.

Clinical evaluation of the Takeda Medical (A & D) TM 2420 ambulatory blood pressure monitor. Practical experience and comparison with direct and indirect measurements.

Takeda Medical (A & D) TM 2420 is an automatic ambulatory blood pressure monitoring system employing the auscultatory technique. The device was used under stable conditions and compared to readings from the Hawksley random-zero sphygmomanometer using a double headset stethoscope and a Y-connection. We tested 85 subjects (aged 13-89 years, systolic blood pressure 85-212 mmHg, diastolic blood pressure 40-116 mmHg) and found a difference amounting to 1.6 +/- 6.7 mmHg (mean +/- SD) for systolic and 2.1 +/- 4.5 mmHg for diastolic readings (Hawksley-TM 2420). In 62 subjects a comparison with simultaneous measurement on the opposite arm with the Hawksley manometer showed similar results. When comparing intra-arterial readings from 10 subjects, a difference (intra-arterial-TM 2420) of -1.9 +/- 12.1 mmHg was found for systolic pressures, while the diastolic difference was -10.7 +/- 8.7 mmHg. Twenty-four hour monitoring was performed on 80 subjects; 70 of these yielded usable tracings. The proportion of successful recordings was acceptable, but the device was not suitable for bicycle stress testing. The quality of the accessories provided with the equipment could be improved, but in spite of this the monitoring system was found to be recommendable for clinical use.