Diuretics and Circadian Rhythm of Blood Pressure.

In patients with essential hypertension it has been postulated that the lack of nocturnal fall in blood pressure (nondippers) is associated with more serious end organ damage than in patients whose blood pressure falls during the night (dippers). Although the mechanism of abnormal circadian blood pressure rhythm remains unclear, our recent studies have revealed the importance of kidneys in the genesis of the rhythm. We found that in patients who have a sodium sensitive type of hypertension, blood pressure failed to fall during the night, and both sodium restriction and diuretics shifted circadian rhythm of blood pressure from nondipper to dipper. In addition, we identified the sodium sensitivity of blood pressure as an independent risk factor for cardiovascular morbidity in patients with essential hypertension. Diuretic-based treatment may have an additional therapeutic advantage to relieve the renal and cardiovascular risks by different ways: systemic blood pressure reduction and normalization of circadian blood pressure rhythm. (c)2000 by Le Jacq Communications, Inc.