The following is a summary of “ICD-9 to ICD-10 transition has not improved identification of rapidly progressing stage 3 and stage 4 chronic kidney disease patients: a diagnostic test study,” published in the February 2024 issue of Nephrology by Jalal et al.
Though the standard tool for classifying diseases, International Classification of Diseases (ICD) codes, especially for rapidly progressing chronic kidney disease (CKD), were found inaccurate, prompting the 2016 revision to ICD-10.
They involved 315,903 patients (2016 to 2021), converting outpatient serum creatinine measurements to estimated glomerular filtration rate (eGFR) to detect stage-3 and advanced CKD patients clinically diagnosed eGFR-CKD. Additionally, CKD-staging codes from the same period for 59,386 patients were used to identify stage-3 and advanced patients diagnosed by ICD-code (ICD-CKD). A diagnostic accuracy comparison was done between eGFR-CKD and ICD-CKD for 334,610 patients.
The results showed 5,618 patients analyzed for progression, 72 were classified as eGFR rapid progressors, while 718 qualified as ICD rapid progressors. Sensitivity was 5.56%, with a positive predictive value (PPV) of 5.6%. Among the patients diagnosed with eGFR-CKD stage-3 (34,858), 17,549 were also identified as ICD-CKD stage-3, yielding a sensitivity of 50.34% and a PPV of 58.71%. For eGFR-CKD stage-4 (4,069 patients), there were 2,750 ICD-CKD stage-4 patients, resulting in a sensitivity of 67.58% and a PPV of 42.43%. Finally, 959 patients reached eGFR-CKD stage-5, with 566 ICD-CKD stage-5 patients, indicating a sensitivity of 59.02% and a PPV of 35.85%.
Investigators concluded that recent ICD revisions improved CKD staging, but stage-5 sensitivity remained low, suggesting further refinement.
Source: bmcnephrol.biomedcentral.com/articles/10.1186/s12882-024-03478-1