Mortality Rate for MI, PE, Stroke Decreased in Patients on Dialysis

A study published in JAMA Network Open found that patients receiving dialysis had decreased mortality rates vs the general population. The study aimed to assess the mortality of a large cohort of European patients who were receiving dialysis and compare them to the general population.

The study included adult patients who were receiving dialysis in 11 European countries providing individual patient data to the European Renal Association (ERA) Registry: Austria, Belgium, Denmark, Finland, Greece, Iceland, the Netherlands, Norway, Scotland, and Sweden, and the Spanish regions of Andalusia, Asturias, Basque Country, Catalonia, and Cantabria. The registry collects all data about patients who received kidney replacement therapy, including date of birth, sex, primary kidney disease, date of initiation of kidney replacement therapy, and date and cause of death.

Patients who started their dialysis between January 1, 1998, and December 31, 2015, and who were followed for up to 3 years until death—accounting for the recovery of kidney function, kidney transplantation, or loss to follow-up—were included in this study. Cause of death was categorized according to the ERA Registry coding system, and mortality data for the general population in the corresponding 11 European countries were obtained from the World Health Organization.

There were 220,467 patients receiving dialysis who were included in this study. The median (IQR) age was 68 (56.5-76.4) years, and 37.2% were female. The percentage of men receiving dialysis increased from 61.0% between 1998 to 2003 to 64.4% for 2010 to 2015. The median follow-up was 2.4 years.

Diabetes was the most common cause of kidney failure, and 22.7% of the patients underwent kidney transplantation during the observation period.

There were 83,912 patients who died during follow-up. Myocardial infarction (MI) was the cause of death in 9.1% of cases, stroke in 6.0%, and pulmonary embolism (PE) in 0.5%. In the general population, 15,835,391 people died during the study period. There were 7.5% who died from MI, 6.1% who from stroke, and 0.5% from PE.

The mortality rate for MI decreased for patients receiving dialysis by 4.0% (95% CI, 2.7%-5.3%) per year from 1998 to 2007 and by 6.9% (95% CI, 8.4%-5.4%) per year from 2007 to 2015. There was also a decline in mortality rates for the general population. The annual percentage change (APC) was –3.8% (95% CI, –5.0% to –2.5%) from 1998 to 2002 and –5.3% (95% CI, –5.5% to –5.1%) from 2003 to 2015.

Mortality rates for stroke were similar to the MI rates. Mortality decreased in both the population undergoing dialysis (APC, –3.9%; 95% CI, –4.5% to –3.3%) and the general population (APC, –4.1%; 95% CI, –4.3% to –3.9%). PE mortality rates also saw a decline in patients receiving dialysis (APC, ­–5.6%; 95% CI, –7.2% to –3.9%) and the general population (APC, –3.2%; 95% CI, –3.4% to –2.9%).

There were no decreased in the mortality rates of other causes of death in patients receiving dialysis from 1998 to 2003, but there was a decline from 2003 to 2015 (APC, –0.9%; 95% CI, –1.2% to –0.5%). The mortality rate in the general population decreased from 1998 to 2009 but increased slightly from 2009 to 2014 (APC, 1.0%; 95% CI, 0.3%-1.7%).

There were some limitations to this study. Information on comorbidities, medication use, and laboratory data was not available and could not be evaluated for the association between them. There were no data on baseline estimated glomerular filtration rate to investigate changes in how dialysis initiation could have influenced the results, and there was no information on nonfatal events.

The researchers concluded that their research suggest that mortality rate ratios for MI, stroke, and PE in patients receiving dialysis decreased over time compared with the general population.

Reference

Ocak G, Boenink R, Noordzij M, et al. Trends in mortality due to myocardial infarction, stroke, and pulmonary embolism in patients receiving dialysis. JAMA Netw Open. Published online April 1, 2022. doi:10.1001/jamanetworkopen.2022.7624