Background: In large epidemiological studies and using serum creatinine or estimates of glomerular filtration rate (GFR), blood pressure has emerged as a predominant determinant of the age-associated decline in renal function.
Methods: The present longitudinal study (median follow-up period of 5.8 years) was conducted in 132 never-treated patients with essential hypertension at baseline. The effect of treatment on the GFR and effective renal plasma flow, estimated by urinary clearances of isotopic markers, was assessed.
Results: Satisfactory control of hypertension (<140/90 mmHg) was achieved in 57% of the population. During follow-up, the yearly change in the GFR was -1.72+/-0.21 ml/min per year (mean+/-SEM). In univariate regression analysis, the change in the GFR was correlated with baseline pulse pressure (r=-0.27, P=0.002), whereas no influence of systolic, diastolic or mean blood pressures, as well as baseline albuminuria or left ventricular mass index, was found. Multivariate logistic regression analysis showed that only baseline pulse pressure conveyed a significant odds ratio of accelerated decline of GFR (>median of 1.5 ml/min per year), independently of age, baseline GFR, mean blood pressure and other known cardiovascular risk factors. No influence of the type of antihypertensive treatment (64% of the population had received angiotensin-converting enzyme inhibitor) was detected.
Conclusion: Pulse pressure (a marker of arterial stiffening) is suggested as an independent determinant of the treatment-associated decline in renal function in essential hypertension. No influence of target organ damage (albuminuria of left ventricular hypertrophy) was detected.