Microalbuminuria in hypertensives is related with blood pressure variability measured by 24-hour blood pressure standard deviation

Abstract

In hypertensives 24-h BP standard deviation (24-h BP S.D., measuring BP variability) has been related to organ damage progression independently on 24-h mean BP. In hypertensives, microalbuminuria (MA) measured after antihypertensive treatment have a particularly high prognostic value for cardiovascular-renal deterioration. We studied the relationship between 24-h BP S.D or the index of variation (InV = 24-h BP S.D/square root of average BP) and MA and/or aortic pulse wave velocity (PWV - Complior) in 198 hypertensive patients with an urinary excretion of albumine between 5 and 300 mg/24h after stable antihypertensive medication for > 4 months: 135 were type 2 diabetics (DM), ageing 61 (2), 72 male and 63 were non diabetics (non DM) ageing 60 (2), 32 male. Both index of variation and 24-h BP S.D significantly correlated with albuminuria either in DM (r=0.354, p<0.001) and non DM (r=0.302, p<0.01). In the 1srt, 2nd and 3rd tertiles of distribution of index of variation, there was a significant (p<0.04) trend for albuminuria 37(5), 51(6) and 78 (6) mg/24h and for PWV 12.0 (0.2), 12.7(0.3) and 13.8 (0.2) m/s but not for mean 24-SBP 136(2), 137(2) and 136 (2) mm Hg. For similar age, sex, weight and 24-h BP S.D., in 116 patients on ACEinhibitors or angiotensin receptor blockers based regimens versus 72 patients on other antihypertensive regimens, similar albuminuria levels i.e. 51 (7) v 63 (6) mg/24h, PWV i.e. 12.8 (0.2) v 12.9 (0.2) and 24-h SBP i.e. 137 (2) v 135 (2) mm Hg were observed (all p>0.7). We conclude that in both DM and non-DM hypertensives the 24-h BP variability achieved after antihypertensive treatment may be an important determinant of microalbuminuria level independently of the type of antihypertensive regimens.