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Abstract:
Blood pressure, the central parameter in the diagnosis of arterial hypertension, is subject to a high degree of variability. The dilemma for the evaluating physician is that he has no true value for the resting blood pressure that is both comparable and reproducible. Reproducibility, however, is an essential requirement for all diagnostic procedures in medicine. A standardized ergometric procedure (at workloads of 50 to 100 watts [W]; incremented 10 watts/min; cuff blood pressure measurements) is suitable to obtain comparable, reproducible monitoring of the blood pressure response in both pressure response in both normotensive subjects and hypertensive patients. The blood pressure behavior during and after ergometric exercise was investigated in 552 males in order to clarify if this standardized procedure is suitable for differentiating between normotensive subjects and hypertensive patients. The following normal upper limits for blood pressure values in men and women between the ages of 20 and 50 years of 200/100 mmHg (mean + 1 SD) at a workload of 100 W as well as 140/90 mmHg in the fifth minute of the recovery phase were obtained. Patients suffering from mild hypertension showed significantly (p less than 0.001) higher blood pressures (213 +/- 22/116 +/- 11 mmHg) at 100 W and after exercise than age-matched normotensives (188 +/- 14/92 +/- 9 mmHg) but significantly (p less than 0.001) lower values than hypertensives with stable hypertension (225 +/- 22/126 +/- 11 mmHg). Moreover, the systolic pressure response to ergometric work was significantly (p less than 0.05 to p less than 0.01) influenced by age. Using the normal upper limits for blood pressure during and after ergometry, the ergometric procedure revealed that 50% of the patients with borderline hypertension at rest could be classified as hypertensives. Their blood pressure response at 100 W (216 +/- 21/113 +/- 8 mmHg) did not significantly differ from the patients with mild hypertension. In contrast, in the 50% who reacted negatively to ergometric testing, the systolic blood pressure response at 100 W (204 +/- 18 mmHg) was significantly (p less than 0.01) lower than that of those who demonstrated a positive reaction, revealing exactly the same diastolic blood pressure value of 92 mmHg as the normotensives. Follow-up examinations several years (average 3.8 years) subsequently showed that 97% of the ergometric-positive borderline hypertensives developed established hypertension. Thus an early diagnosis of arterial hypertension was achieved years before its established manifestation.(ABSTRACT TRUNCATED AT 400 WORDS)