[Ambulatory blood pressure profile during 48 hours in patients treated with chronic hemodialysis]

Hypertension is one of the severest cardiovascular risk factor in subjects affected by end-stage renal disease in chronic hemodialysis. The behavior of blood pressure between the first hemodialysis (day 1) and the next one (day 2) was studied in 24 untreated normotensive hemodialysis patients. Patients were between 34 and 83 years (mean age: 60 +/- 12 yrs) and were hemodialysed 3 x 4 hours a week, between 7 and 12 a.m. ABP was recorded at 15 minutes intervals between 7 and 22 hours, and 30 minutes intervals during the night, during 48 hours with a Spacelabs 90202 or 90207 device. The following results were observed: ABP is greater at day 2 (122/74 mmHg) than at the first (117/70 mmHg, p less than 0.001); that increase is not correlated with gaining weight during interdialytic period; after hemodialysis, blood pressure continues to fall during 2 or 3 hours until a level of 119 mmHg; low values continue during postdialysis and during the first night; the following day, ABP increases progressively during the morning and during the evening; before the second hemodialysis, the increase is suddenly faster; circadian rhythm is lost in 9/24 patients; in 17/24 patients, nocturnal decrease of BP is lower than 5%; age and ancientness of hemodialysis are the most important factor; rest blood pressure measured by physician before HD is continually higher than diurnal ABP (138/74 vs 121/73 mmHg, p less than 0.001), even if ABP is only analysed during one hour before the second hemodialysis (129/77 mmHg).