SAT-240 INTER-DIALYTIC WEIGHT GAIN IN HEMODIALYSIS PATIENTS - EPIDEMIOLOGY AND EVALUATION OF THE CLINICAL OUTCOMES

Abstract

Inter-dialytic weight gain (IDWG) has been linked to various complications in hemodialysis (HD) patients, especially cardiovascular (CV) complications. High ultrafiltration (UF) rate in relation to dialysis time has also a similar impact in various studies. Furthermore, high IDWG has been associated with all cause and CV mortality. The IDWG is also influenced by the nutritional status of HD patients. We investigated the trends of IDWG in patients on regular HD aiming to examine: (1) trends of IDWG among patients in relation to different variables and comorbidities e.g. age, hypertension, diabetes, CV disease...etc.; (2) associations of high IDWG with frequency of hospitalization due to systemic volume overload and the need for extra dialysis sessions, and (3) the impact of high IDWG on the frequency of intra-dialytic hypotension (IDH). One hundred and twenty maintenance HD patients were enrolled in this study. All patients had been receiving HD for at least 3 months, on a 4 hour, thrice weekly basis. The data collected included; age, gender, duration on HD (in months), pre- and post-HD body weights (on 3 successive sessions), pre- and post-HD blood pressure (BP) measurements (on 3 successive sessions), the type of vascular access and the average blood flow rate, dialysis efficiency (based on average Kt/V), and the presence or absence of residual kidney function. The presence of various comorbidities has been recorded including; diabetes, hypertension, coronary artery and peripheral vascular diseases, heart failure, cerebrovascular disease, and other disorders. The estimated IDWG was calculated based on the average between pre- and post- dialysis weights that were recorded on 3 consecutive dialysis sessions. The estimated IDWG was expressed in kilograms and as a percentage of the patients’ dry weight. We considered an estimated average IDWG of 4% as a cutoff value between low and high IDWG. We defined IDH as the drop of systolic blood pressure of 20 mmHg or more during HD compared to the pre-dialysis blood pressure and/or a systolic blood pressure that is less than 90 mmHg. We have recorded that 50.0% of those younger than 55 years had IDWG ≥ 4%. On the other hand, only 31.7% of those aged 55 years or more had IDWG ≥ 4% (p=0.041). There was no significant gender difference regarding IDWG. Among those who had IDWG ≥ 4%, 81% of these patients had at least one hospital admission due to volume overload or the need for extra HD session(s). On the other hand, only 19% of those having IDWG < 4% had been admitted or got extra HD sessions (p<0.001). Of those who were admitted (over 12 months) due to volume overload; 74.1 % had IDWG ≥ 4%, while 25.9% had IDWG < 4% (p< 0.001). Regarding IDH, 87% of patients having IDWG ≥ 4% had at least one episode of IDH/week. On the other hand, only 22.5% of those with IDWG < 4% had one episode of IDH/week (p<0.001). When analyzing those who had at least one IDH episode/week; 72.9% of them had IDWG ≥ 4%, while only 27.1% had IDWG < 4% (p<0.001).View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT) In HD patients, the frequency of hospital admission due to volume overload and the need for extra HD sessions is strongly related to the amount of IDWG (> 4% in our patients). The same stands for the frequency of IDH. Thus a control of IDWG in HD patient is of great importance, keeping in mind the importance the nutritional status of HD patients that may also impact IDWG.