Compared with patients in European countries and Japan, patients using in-center hemodialysis in the United States showed a significant increase in serum phosphorous levels , according to data published in Kidney Medicine.

“Mineral bone disorders … [are] a frequent consequence of chronic kidney disease, more so in patients with kidney failure treated by kidney replacement therapy,” Murilo Guedes, MD, from Pontificia Universidade Católica do Parana in Brazil, and colleagues wrote. “Despite the wide availability of interventions to control serum phosphate and [parathyroid hormone] PTH levels, unmet gaps remain on optimal targets and best practices, leading to international practice pattern variations over time.”

Using data from the international prospective study of in-center hemodialysis, the Dialysis Outcomes and Practice Patterns Study (DOPPS), researchers aimed to assess international trends of mineral bone disorder biomarkers and treatments between 2002 and 2021. Countries in the study included Belgium, France, Germany, Italy, Spain, Sweden, the United Kingdom, Japan and the U.S.

From 2002 to 2021, the mean phosphate level changed in the U.S. from 5.7 mg/dL (2002) to 5 mg/dL (2012) to 5.6 mg/dL (2021). The ratio of patients on in-center hemodialysis with phosphate greater than 5.5 mg/dL in the U.S. rose from 28% in 2013 to 42% in 2021, whereas the ratio of such patients in Europe and Japan was 18% and 28%, respectively.

Despite the increase in phosphate levels in the U.S., researchers did not observe significant changes in phosphate binders type that could explain the growth. In 2021, data revealed sevelamer and calcium-based phosphate binders made up 23% and 44% of all phosphate binder prescriptions, respectively.

Researchers suggested that levels could have risen due to limited randomized controlled trials that led to unstandardized phosphate control, counseling toward a less stringent dietary phosphorous control, lower effective daily dosing of phosphate binders, increasing target limits, a decline in patient adherence, distinct practice patterns for vitamin D analogs prescriptions and a potential misinterpretation of the 2009 Kidney Disease: Improving Global Outcomes Guidelines.

Further, the researchers wrote that Europe and Japan may have achieved lower serum phosphate levels due to greater uptake of hemodiafiltration.

Due to stable phosphate levels of patients in Europe and Japan, researchers believe it is feasible for patients in the U.S. to achieve and maintain lower phosphate levels. A possible solution may be the use of novel phosphate-lowering agents in CKD, such as tenapanor.

“Within several years, the landscape regarding approaches to optimal phosphate management may be clearer, as data from large clinical trials and the availability of novel pharmacological interventions may clarify remaining uncertainties that have exacerbated wide practice variation across the globe,” Guedes and colleagues wrote. They added, “From the patients’ perspective, we can hope that better evidence will lead to gains in quality of life, including reduced pill burden and more palatable nutritional guidance, and plausibly help to extend survival and limit medical complications.”