Ambulatory blood pressure during diseases of the kidney.

During the last few years there has been a renewal of interest in blood-pressure-induced kidney damage due to a progressive increase in the incidence and prevalence of hypertension and vascular diseases as a cause of end-stage renal disease (ESRD). The need to prevent ESRD demands a continuation of effort to make the early identification of hypertensives who are at risk possible and to provide them with effective antihypertensive therapy. Since ambulatory blood pressure monitoring has been used successfully to assess blood pressure and identify risk markers for cardiovascular diseases, a logical approach would be to use it also to identify the risk markers for ESRD. Higher than normal percentages of non-dippers have been found among subjects with renal failure, during dialysis (haemofiltration, peritoneal dialysis and continuous ambulatory peritoneal dialysis), among cases of renovascular hypertension or cystic kidney disease and among cases of renal transplantation. Although this non-dipping pattern might be related to the presence of severe hypertension in some patients, such as those who have renovascular hypertension, in other cases the abnormal circadian variability is present with milder forms of hypertension or even in the absence of hypertension. Monitoring ambulatory blood pressure could offer advantages for protection of renal function during antihypertensive treatment of subjects with mild renal insufficiency. Furthermore, ambulatory blood pressure monitoring seems to have been prognostic for the development of proteinuria in a group of refractory hypertensives. Whether higher than normal nocturnal blood pressures and the non-dipping pattern are causes or consequences of renal disease should be addressed in prospective studies. The above notwithstanding, assessment of nocturnal blood pressure seems to be an important aid in the management of patients with hypertension-related renal disease and of patients who are susceptible to developing it.