HEALTH RELATED QUALITY OF LIFE AFTER KIDNEY TRANSPLANTATION: A SYSTEMATIC REVIEW

Abstract Background and Aims Health-related quality of life (HRQOL) is becoming an increasingly important outcome in kidney transplantation besides graft function and patient survival. It is of clinical interest to understand whether kidney transplant recipients (KTRs) experience better HRQOL after the invasive procedure and to what extent they can restore HRQOL. To the best of our knowledge, the last relevant systematic review and meta-analysis, which compared HRQOL in KTRs to patients on dialysis, only included eligible publications before 2005. With the considerable improvement in nephrology care and the exponential increase in studies focusing on HRQOL in the past two decades, an updated overview of the current literature is needed. Moreover, to gain a comprehensive picture of HRQOL in KTRs, it is also necessary to include relevant comparison groups such as the general population and healthy controls to understand to which extent HRQOL can be restored to a “pre-CKD” level. To describe HRQOL in KTRs, this systematic review summarizes the published literature to date that compared HRQOL of KTRs with other relevant populations (i.e. patients receiving dialysis, patients on the waiting list for kidney transplantation, patients with chronic kidney disease [CKD] not receiving dialysis, the general population, and healthy controls) and themselves before kidney transplantation. To avoid potential bias, we include studies using different HRQOL questionnaires. Method A thorough literature search was conducted in PubMed, EMBASE, Web of Science, and COCHRANE Library. Studies were included when published between January 2000 and October 2020, and when comparing HRQOL in adult KTRs to the relevant populations. The quality of included studies was assessed using the Risk Of Bias Assessment tool for Non-randomized Studies (RoBANS). Prespecified study characteristics and HRQOL scores were extracted. Due to substantial clinical and methodological heterogeneity, results were summarized in a narrative manner without pooled estimates. Results 44 studies comprising 6929 KTRs were included in this systematic review. The mean age of KTRs in all studies ranged from 29 to 72 years old, and only two studies were conducted in an elderly cohort (≥ 65 years). The majority of studies (93%) reported a higher percentage of male KTRs (median 62%; range 43% to 86%). The average time of HRQOL-measurements after kidney transplantation ranged from 1 to 234 months after the operation. 50% of the studies had a cross-sectional design; 32% had a prospective, and 18% had a retrospective design; and 55% of the studies were single-center studies. While taken into account study heterogeneity, KTRs reported a higher HRQOL after kidney transplantation compared to pre-transplantation and compared to patients receiving dialysis with or without being on the waiting list, especially in disease-specific domains (i.e. burden of kidney disease, effect of kidney disease, and symptoms). Additionally, KTRs had comparable to marginally higher HRQOL compared to patients with CKD stage 3-5. When compared to healthy controls or the general population, KTRs reported similar HRQOL in the first one or two years after kidney transplantation, and lower physical HRQOL and lower to comparable mental HRQOL with an average post-transplant time longer than two years. Conclusion Patients generally report better HRQOL after successful kidney transplantation compared to themselves before the operation and patients receiving dialysis with or without waiting for kidney transplantation, but HRQOL of KTRs does not return to “pre-CKD” HRQOL levels. Future studies investigating risk factors for impaired HRQOL are needed to maximize the long-term benefit of kidney transplantation.