Adherence to Kidney Disease: Improving Global Outcomes Mineral and Bone Guidelines for Monitoring Biochemical...

Mineral and bone disorder (MBD) is common in patients with chronic kidney disease (CKD), and is associated with risk of fractures, cardiovascular disease, and death. Kidney Disease: Improving Global Outcomes (KDIGO) guidelines recommend monitoring CKD-MBD biochemical markers, including parathyroid hormone (PTH), phosphorus, 25-hydroxyvitamin D (25D), calcium, and alkaline phosphatase (ALP), in patients with moderate-to-severe CKD.

To determine guideline adherence, we used administrative claims records from the 20% sample of Medicare beneficiaries with Parts A, B, and D coverage, 2007 to 2015, and identified cohorts of patients with nondialysis stage 3, 4, or 5 CKD. Testing for biochemical markers during follow-up was defined based on laboratory procedure codes. Baseline factors associated with laboratory testing were determined using logistic regression. All analyses were performed separately by CKD stage.

A total of 640,946 stage 3, 136,278 stage 4, and 22,076 stage 5 CKD patients, 50.2-52.9% women, mean age 74.4-78.0 years, were followed for a mean of 2.5, 1.3, and 0.7 years respectively. The frequency of testing was low for PTH (35.2-48.2%), phosphorus (46.6-62.0%), and 25D (29.3-46.7%). Testing was somewhat higher for calcium (88.1-95.4%) and ALP (63.5-88.1%); most tests were features of larger panels (e.g., basic metabolic panel). Older age, most comorbid conditions, and lack of prior nephrology care were associated with lower likelihood of testing.

In fee-for-service Medicare beneficiaries, laboratory testing for CKD-MBD biochemical markers appears to be suboptimal in relation to KDIGO guidelines. Competing priories, such as management of comorbid disease and preparation for renal replacement therapy, may distract from CKD-MBD monitoring.