Is Interdialytic Blood Pressure Profile Related to Structural Changes of Arteries in Haemodialysis Patients?

Dr. F. Fabbian, Department of Nephrology, Arcispedale S. Anna, Corso Giovecca 203, I-44100 Ferrara (Italy) Table 1. Mean 48-hour daytime, nighttime and nocturnal fall values of systolic and diastolic BP of the three groups of patients (mean ± SEM) Dear Sir, Risk factors for atherosclerosis occur more frequently in patients with chronic renal failure (CRF) than in the general population and hypertension is the main determinant in the aetiology of it [1]. Atherosclerotic cardiovascular disease is a significant cause of morbidity and mortality in patients with end-stage renal failure (ESRF) [2]. A relationship has been shown between the reduction in nocturnal blood pressure (BP) fall and target organ damage. Reduced nocturnal BP fall is frequently found in CRF [3]. The aim of this study was to relate the BP profile of the interdialytic period to atherosclerotic vascular damage. Eighteen haemodialysis patients (7 M, 11 F; age 61 ± 8.8 years) were studied. Causes of CRF were ischaemic renal disease (n = 5), interstitial nephritis (n = 4), glomerulone-phritis (n = 3), polycystic kidney disease (n = 3), eclampsia (n = 1), diabetes (n = 1) and it was unknown in 1 patient. Bicarbonate haemodialysis was performed 3 times/week, 3.5-4 h each session. All the patients had an ambulatory BP monitor (Spacelabs 90207) placed immediately upon completion of the dialysis treatment and had it removed before the initiation of their next haemodialysis session, approximately 45 h later. BP monitoring was recorded every 15 min during the day (07:00-23:00 h) and half hourly during the night (23:00-07:00 h). Mean 48hour-diur-nal and nocturnal BP for both systolic and diastolic BP were calculated. Dipping status was defined as a reduction in nighttime MAP > 10% of the daytime MAP. Vascular damage was evaluated by B-mode ultrasound technique of carotid and leg arteries in order to detect normal vessels (group 1), calcinosis of the arterial wall (group 2) and plaques producing a lumen stenosis ≥40% (group 3). ANOVA for parametric data and Krus-kal-Wallis test for nonparametric data were used for statistical analyses. Seven patients were classified as group 1 ‚ 5 as group 2 and 6 as group 3. Age (58 ± 4 vs. 60 ± 1 vs. 65 ± 4 years; NS), history of hypertension (10 ± 2 vs. 11 ± 3 vs. 18 ± 3 years; NS), length of time on dialysis (51 ± 8 vs. 44 ± 17 vs. 49 ± 14 months; NS), choles-