PATIENT BENEFITS OF NEPHROLOGICAL FOLLOW-UP BEFORE THE INITIATION OF RRT-AN OBSERVATIONAL RETROSPECTIVE ANALYSIS

ABSTRACT

BACKGROUND AND AIMS: The clinical follow-up of CKD patients by nephrologists before RRT initiation (RRTi) is recommended by the practice guidelines starting with stage 3b CKD [1]. Despite this, the real-life implementation in clinical practice suggests otherwise, based on the paucity of papers reporting on the matter [2, 3]. In Romania, where the representation of the nephrology outpatient care is scarce, partly because of the low number of specialists, the establishment of outpatient clinics attached to dialysis units could be a solution. The purpose of this analysis is to evaluate, for the first time, if nephrological monitoring through the Diaverum outpatient clinics has benefits for CKD patients. METHOD: A total of 344 patients from 9 Diaverum clinics have been evaluated (335 haemodialysis, 9 peritoneal dialysis), our present analysis retaining only those starting haemodialysis, of which 118 started RRT in the 3 years between 1 January 2015 and 31 December 2017 and were monitored through the nephrology outpatient and 217 were patients there were not referred to a nephrology unit until RRTi, in the 2 years between 1 July 2016 and 1 July 2018. Clinical and laboratory data were gathered at RRTi and the follow up was investigated over a period of 3 years for both groups, starting from the end of the inclusion period, using anonymized records from the electronic database of Diaverum. Collected data were compared using the Pearson test for nominal variables and the Student's t-test and Wilcoxon Mann-Whitney U-tests for continuous variables. Survival analysis was employed using the Kaplan-Meier estimate and Cox regression models. RESULTS: The patient groups had similar general characteristics most were men, >40% being elder (>65 yo), ∼30% had DM and both groups were comprised of subjects with multiple comorbidities (a mean Charlson score of 6). For patients that were not nephrologically referred, RRT was started in 100% of the cases using a CVC, while AVFs were employed in a majority of those followed through the outpatient clinics. In both groups, the mean eGFR was similarly <10 mL/min/1/73 m2, but >7 mL/min/1.73 m2, reflecting an alignment to clinical practice guidelines [1]. The median level of haemoglobin and the percentage of those with an optimal level of haemoglobin were higher in the group of monitored patients (9.9 versus 8.4 g/dL, respectively, 42% versus 15%).The nutrition status faired better in monitored patients BMI (26 versus 23.3 kg/m2) and serum albumin (3.8 versus 3.5 g/dL). Serum calcium levels were higher (8.8 versus 8.3 mg/dL) and serum iPTH levels were lower (264 versus 331 pg/mL) in monitored patients, suggesting a better control of CKD-MBD, but serum phosphate was higher (5.7 versus 4.64 mg/dL), possibly reflecting a better nutrition status. The number of hospital admissions, COVID-19 cases and deaths are hard to compare, given the different observation periods that covered different periods and waves of the COVID-19 pandemic. However, hospital admissions and COVID-19 cases seemed more frequent in those that were not monitored. The 4 year survival rate was significantly higher (59% versus 51%) in the Kaplan- Meier analysis for those monitored through the outpatient. In the multivariate analysis, statistically significant associations with mortality were observed for diabetic and unmonitored patients. A major bias in our analysis is the difference between the periods of follow-up, which featured different periods of the COVID-19 pandemic. CONCLUSION: This is the first observational analysis on a nephrological patient population from Romania, which was followed through outpatient units until the initiation of RRT. Patient monitoring before RRTi potentially allows for a better control of the main complications of CKD (anaemia, CKD-MBD), a better preparation for RRTi (a more frequent use of an AVF) and possibly for an improvement in morbidity and mortality, as suggested by previous studies on the benefits of nephrological monitoring before RRTi [4, 5].