American Journal of Hypertension · 1994 · 370 citations · 0 references
Microalbuminuria occurs in about 40 % of patients with essential hypertension, yet its relationship with office blood pressure has been inconsistent. The study aimed to determine whether urinary albumin excretion correlates more closely with average diurnal, nocturnal, or 24‑hour blood pressure than with office measurements. Sixty‑three hypertensive patients and 21 healthy volunteers were enrolled, with patients classified as dippers or nondippers based on a nighttime fall of at least 10/5 mm Hg. Nondippers exhibited higher nighttime systolic and diastolic pressures and markedly greater urinary albumin excretion (median 42 mg/24 h vs 17.5 mg/24 h), with significant correlations between nighttime and 24‑hour blood pressures and albumin excretion, indicating greater renal damage in nondippers. Am J Hypertens 1994;7:23–29.
Microalbuminuria has been shown in approximately 40% of patients with essential hypertension. Previous studies have failed to demonstrate any consistent relationship between microalbuminuria and levels of office blood pressure. Because average ambulatory blood pressure correlates with incidence of cardiovascular morbidity and mortality better than office blood pressure, we have studied whether levels of urinary albumin excretion correlate with average diurnal, nocturnal, or 24-h blood pressure better than with office blood pressure. Sixty-three patients with essential hypertension and 21 healthy volunteers were included in the study. Twenty-four hypertensive patients failed to show the normal nighttime fall in blood pressure of at least 10/5 mm Hg and were defined as "nondippers"; the remaining were defined as "dippers." Office blood pressure was not different between dippers and nondippers. However, nighttime systolic and diastolic blood pressures were significantly greater in nondippers than in dippers. The median urinary albumin excretion in nondippers (42 mg/24 h) was significantly greater (P < .001) than in dippers (17.5 mg/24 h), and in normal subjects (8.6 mg/24 h). A significant correlation was present between nighttime systolic and diastolic blood pressure and urinary albumin excretion (UAE) and between 24-h systolic blood pressure and UAE in all hypertensive patients; in addition, a significant correlation was present between 24-h diastolic and nighttime diastolic blood pressure and UAE in nondippers. The increased amount of UAE in nondipper hypertensive patients suggests the presence of greater renal damage than in dippers. Am J Hypertens 1994;7:23–29