Abstract
Twenty-four-hour blood pressure (BP) variations and autonomic nervous system disorders were studied in 14 hemodialysis (HD) patients who were not taking antihypertensive drugs. Twenty-four-hour BP values, before and after HD, were measured at intervals of 30 minutes by using a non-invasive automatic ambulatory BP recorder (ABPM630). The characteristics of 24-hour BP variations, with reference to BP during the night, were classified into three types: (1) down type, in which nocturnal BP was significantly lower than diurnal BP (p<0.01), (2) flat type, showing no significant change between nocturnal and diurnal BP, and (3) up type, in which nocturnal BP was significantly higher than diurnal BP (p<0.01). The Shellong test and the CV% of the R-R interval on ECG were also studied.
1) As regards the changes in systolic BP (SBP), the down, flat and up types were seen in 4, 8 and 2 cases before HD, and 6, 5 and cases after HD, respectively. As to changes in diastolic BP (DBP), the down, flat and up types were seen in 6, 7 and 1 cases before HD, and 7, 5 and 2 cases after HD, respectively. Patients changing from flat to down type, from down to flat type, or from flat to up type were also present. Changing patterns of DBP were not always the same as those of SBP. It was shown that the 24-hous BP patterns before and after varied among HD patients. 2) There was a positive correlation between BP difference on the Shellong test and SBP or DBP differences during the day and night after HD. The sympathetic nerve may contribute the increased nocturnal BP after HD. We should pay attention to high BP at night in cases with severe sympathetic nervous system disorders.
