[Computer-assisted assessment of the 24-hour blood pressure profile in essential and secondary hypertensive patients].

In 17 essential hypertensives, 13 secondary hypertensives and 9 normotensives, noninvasive 24 h blood pressure monitoring was performed. By a computer-aided evaluation according to the Cosinor method, circadian periodicity was quantified and expressed as a coefficient of periodicity in %. This coefficient for systolic pressure was higher in essential hypertensives and normotensives than in secondary hypertensives (42.9 +/- 18.0 et 43.0 +/- 16.7 versus 28.2 +/- 17.7; p less than 0.05). The circadian periodicity of diastolic pressure showed no significant differences. Despite the large overlap, coefficients of periodicity below 20% for systolic pressure may suggest secondary hypertension.