An updated systematic review of the risk factors for unplanned dialysis initiation.

Background: Previously, a comprehensive review of the risk factors for unplanned dialysis initiation (UDI) was conducted by Hassan et al. (2019), based on studies published up to the end of 2017. They demonstrated that high-quality data and well-designed studies on the subject are lacking. Thus we updated their review to establish the modifiable factors associated with UDI.

Methods: MEDLINE and Embase were searched from January 2018 to August 2023. Following several rounds of screening, we identified 17 international studies (the majority of which were based in Europe) that met the eligibility criteria.

Results: Many of the included studies were well designed, utilised large datasets and adopted properly adjusted analyses to examine associations between patient characteristics and UDI. Definitions of UDI varied across studies, i.e. timeliness of presentation, vascular access type, initiating dialysis as an inpatient/outpatient or for life-threatening indications. The most common risk factors reported were cardiovascular disease, older age, lower body mass index, cause of kidney disease, cancer, diabetes, lower serum albumin, faster decline in kidney function and fewer number of nephrology visits prior to dialysis start. These were in line with those reported by Hassan et al., however, our updated review revealed several other important predictors of UDI, e.g. worse coding of chronic kidney disease in the general practitioner health record, lower health literacy and having acute kidney injury.

Conclusions: Our review provides new insights into reasons why people start dialysis in an unplanned manner, many of which are modifiable, thus contributing to efforts in reducing the rate of UDI.