SP109THE USE OF SPECTROSCOPIC BIO-IMPEDANCE TO ASSESS PRE-HEMODIALYSIS VOLUME OVERLOAD IN PREVALENT PATIENTS CORRELATES WITH DECREASED SERUM ATRIAL NATRIURETIC PEPTIDE AND MINOR DOSES OF ANTIHYPERTENSIVE MEDICATION

Abstract

Introduction and Aims: Hypertension (HTN) due to volume overload (VOL) is a common finding in hemodialysis (HD) patients ( pts) and it increases cardiovascular mortality. HTN du to VOL correlates with increased serum values of atrail natriuretic peptide (sANP). HD pts might benefit from a better systolic blood pressure (SBP) control if VOL is determined and accurate dry weight (DW) is targeted at HD treatments (tx). VOL estimation and accurate DWin HD pts is deficient with conventional clinical practice (physical examination, pre‐HD weight gain, intra‐dialytic blood to avoid hypotension). The Spectroscopic Bio‐Impedance BCM (Body Composition Monitor, Fresenius Medical Care, Ger) is a non‐invasive tool than can be used in the clinical settings of HD practice and helps to determine pts VOL and thus to target an accurate DW. The purpose of this study was to compare sANP changes and its impact on antihypertensive medication when VOL was assessed with the BMC vs conventional (CV) method. Methods: 8 weeks follow up of a randomized, controlled, open clinical study among HD prevalent pts at Hospital Civil Guadalajara. BMC vs CV VOL assessment pre‐HD tx. Socio‐demographic, clinical, laboratory values were recorded. BP was recorded at the beginning and end of each HD tx. Antihypertensive medication was recorded as well. Ultrafiltration rate never exceeded 1L/hr regardless of the amount of VOL. Improvement in BP was considered when the pts maintained BP values <140 / 90mmHg during the HD tx. sANP was determined baseline and at the end of the study. Results: 2 pts in BCM group dropped out the study (1 kidney transplant, 1 withdraw consent). A 30% reduction in sANP levels was observed in the BCMgroup (7pts vs 2pts in the CV group, RR=4.5 (IC 95% 1.3‐15), p=<0.01). No difference between the groups was observed at the end of the 8 weeks regarding the average SBP (average SPB in the BCM group 122.1 +/‐ 20.7 mmHg vs CV group 124.4 +/‐ 26.9 mmHg (p = 0.85). Nevertheless, when the baseline and final SPB were compared within each group, the BCM group had a statistically significant decrease in the SBP (p = 0.004), while the CV group did not (p = 0.22). 4 Pts in the BMC group (57.5%) stopped antihypertensive medication, whereas none of the pts in the CV group did (RR=0.25 (IC95% 0.09‐0.66), p=0.01). No statistical difference was observed between the 2 groups for disnea (p= 0.58) and cramps (p= 0.43). 3 pts (42%) reached the idealDWin the BCMgroup vs 2 pts (22%) in the CV group (p= 0.59, RR 1.59 (0.49‐5.08)). Conclusions: All the pts in the BCM group decreased their sANP value and 57.5% of them stopped antihypertensive medication, whereas none in the CV group did. With the use of BMC, more HD pts achieved a SBP <140mmHg without significant adverse effects. A longer follow up and largest group of pts is needed to assess these findings in the daily clinical settings. (Table Presented).