Global CKD Mortality Up More Than 40%

The global burden of chronic kidney disease (CKD) has increased substantially since the 1990s, but in many countries people can still not afford adequate care, researchers reported.

An analysis of data from 195 countries found that 1.23 million people died worldwide from CKD in 2017, an increase of 41.5% since 1990, reported Theo Vos, MD, PhD, of the Institute for Health Metrics and Evaluation (IHME) at the University of Washington School of Medicine in Seattle, and colleagues.

In addition, according to the analysis online in The Lancet, there were 697.5 million cases of CKD worldwide in 2017, for a global prevalence of 9.1%. That was a 29% increase from 1990. However, the age-standardized prevalence and mortality rates for CKD have remained relatively stable since 1990, indicating that the increases are driven by an aging population, the researchers said.

Approximately one-third of CKD patients lived in just two countries: China (132 million cases) and India (115 million). Countries with more than 10 million cases included the U.S., Indonesia, Russia, Japan, Brazil, Pakistan, Mexico, Nigeria, Bangladesh, and Vietnam. In total, 79 of the countries in the analysis had more than one million cases of CKD. The analysis was part of the Global Burden of Disease (GBD) study coordinated by IHME.

“The number of individuals with all stages of prevalent CKD reached almost 700 million in 2017, a number larger than that of diabetes, osteoarthritis, chronic obstructive pulmonary disease (COPD), asthma, or depressive disorders,” Vos and co-authors wrote. “GBD ranks CKD as the 12th leading cause of death out of 133 conditions. Globally in 2017, CKD resulted in more deaths than tuberculosis or HIV and was almost equal to the number of deaths due to road injuries.”

“We have not seen the same degree of progress in prevention of CKD mortality as we have for many other important non-communicable disease,” the researchers added. “From 1990 to 2017, the global age-standardized mortality rate declined by 30.4% for cardiovascular disease (CVD), 14.9% for cancer, and 41.3% for COPD, but a similar decline was not seen for CKD.”

The study also assessed the global burden of CKD in terms of disability-adjusted life-years (DALYs). In 2017, CKD resulted in 7.3 million years lived with disability and 28.5 million years of life lost, for a total of 35.8 million DALYs.

Poorer countries bore the brunt of this burden. El Salvador, the Marshall Islands, Mauritius, Micronesia, and American Samoa had the highest estimated rates of age-standardized DALYs, with more than 1,500 per 100,000 population. Slovenia, Finland, Iceland, and Andorra experienced the lowest burden, with less than 120 age-standardized DALYs per 100,000.

Disparities in CKD burden highlight the disparities in treatment access, the study authors said. “For instance, in sub-Saharan Africa, even if individuals requiring renal replacement therapy initiate treatment, retention is low due to inability to pay for ongoing dialysis, and up to 85% of the incident patients are forced to withdraw from this life-saving treatment.”

In an accompanying press release, Vos said, “Chronic kidney disease is a global killer hidden in plain sight. The evidence is clear: Many nations’ health systems cannot keep pace with the dialysis demand. Cases far exceed and are well beyond the ability of those systems to handle. The consequences, literally, are deadly.”

The researchers complied data on CKD epidemiology through systematic literature reviews in PubMed and EMBASE, using search queries combining “chronic kidney disease” and “prevalence.” Data on dialysis and kidney transplant were obtained from medical registries. The investigators calculated disease burden estimates using a Cause of Death Ensemble model (CODEm) and Bayesian meta-regression analyses.

An important limitation of the research, the team said, was lack of quality, population-based studies on the incidence or prevalence of CKD for many countries, especially those in Central and Latin America. As such, the GBD study had to rely on statistical methods and predictive covariate values to estimate the CKD burden in those regions.

In addition, many of the studies included in the analysis were cross-sectional and performed only one laboratory measurement to determine CKD. “Studies suggest that the use of a single decreased eGFR [estimated glomerular filtration rate] determination to characterize CKD may overestimate prevalence by anywhere from 25% to 50%,” the researchers wrote. “It is therefore possible that the results of our analysis represent an overestimate of CKD prevalence.”

However, “kidney disease has a major impact on global health, both as a direct cause of global morbidity and mortality and as an important risk factor for CVD,” Vos and co-authors continued. “Chronic kidney disease is largely preventable and treatable and deserves greater attention in global health policy decision-making, especially in low and middle socio-demographic index geographies.”