Assessment of International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) Code Assignment Validity for Case Finding of Medication-related Hypoglycemia Acute Care Visits Among Medicare Beneficiaries.

OBJECTIVE: Administrative claims are commonly relied upon to identify hypoglycemia. We assessed validity of 14 International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis code assignments to identify medication-related hypoglycemia leading to acute care encounters. RESEARCH DESIGN AND METHODS: A multisite, retrospective medical record review study was conducted in a sample of Medicare beneficiaries prescribed outpatient diabetes medications and who received hospital care between January 1, 2016 and September 30, 2017. Diagnosis codes were validated with structured medical record review using prespecified criteria (clinical presentation, blood glucose values, and treatments for hypoglycemia). Sensitivity, specificity, and positive and negative predictive value (PPV, NPV) were calculated and adjusted using sampling weights to correct for partial verification bias. RESULTS: Among 990 encounters (496 cases, 494 controls), hypoglycemia codes demonstrated moderate PPV (69.2%; 95% confidence interval: 65.0-73.0) and moderate sensitivity (83.9%; 95% confidence interval: 70.0-95.5). Codes performed better at identifying hypoglycemic events among emergency department/observation encounters compared with hospitalizations (PPV 92.9%, sensitivity 100.0% vs. PPV 53.7%, sensitivity 71.0%). Accuracy varied by diagnosis position, especially for hospitalizations, with PPV of 95.6% versus 46.5% with hypoglycemia in primary versus secondary positions. Use of adverse event/poisoning codes did not improve accuracy; reliance on these codes alone would have missed 97% of true hypoglycemic events. CONCLUSIONS: Accuracy of International Classification of Diseases, Tenth Revision codes in administrative claims to identify medication-related hypoglycemia varied substantially by encounter type and diagnosis position. Consideration should be given to the trade-off between PPV and sensitivity when selecting codes, encounter types, and diagnosis positions to identify hypoglycemia.

Excess Death Estimates in Patients with End-Stage Renal Disease - United States, February-August 2020.

End-stage renal disease (ESRD) is a condition in which kidney function has permanently declined such that renal replacement therapy* is required to sustain life (1). The mortality rate for patients with ESRD in the United States has been declining since 2001 (2). However, during the COVID-19 pandemic, ESRD patients are at high risk for COVID-19-associated morbidity and mortality, which is due, in part, to weakened immune systems and presence of multiple comorbidities (3-5). The ESRD National Coordinating Center (ESRD NCC) supports the Centers for Medicare & Medicaid Services (CMS) and the ESRD Networks†,§ through analysis of data, dissemination of best practices, and creation of educational materials. ESRD NCC analyzed deaths reported to the Consolidated Renal Operations in a Web-Enabled Network (CROWNWeb), a system that facilitates the collection of data and maintenance of information about ESRD patients on chronic dialysis or receiving a kidney transplant who are treated in Medicare-certified dialysis facilities and kidney transplant centers in the United States. Excess death estimates were obtained by comparing observed and predicted monthly numbers of deaths during February 1-August 31, 2020; predicted deaths were modeled based on data from January 1, 2016, through December 31, 2019. The analysis estimated 8.7-12.9 excess deaths per 1,000 ESRD patients, or a total of 6,953-10,316 excess deaths in a population of 798,611 ESRD patients during February 1-August 31, 2020. These findings suggest that deaths among ESRD patients during the early phase of the pandemic exceeded those that would have been expected based on previous years' data. Geographic and temporal patterns of excess mortality, including those among persons with ESRD, should be considered during planning and implementation of interventions, such as COVID-19 vaccination, infection control guidance, and patient education. These findings underscore the importance of data-driven technical assistance and further analyses of the causes and patterns of excess deaths in ESRD patients.

Assessment of ICD-10-CM code assignment validity for case finding of outpatient anticoagulant-related bleeding among Medicare beneficiaries.

PURPOSE: To assess performance of International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code assignments for identifying bleeding events resulting in emergency department visits and hospitalizations among outpatient Medicare beneficiaries prescribed anticoagulants. METHODS: Performance of 206 ICD-10-CM code assignments indicative of bleeding, five anticoagulant adverse effect/poisoning codes, and five coagulopathy codes (according to Medicare Parts A and B claims) as assessed among Medicare fee-for-service beneficiaries prescribed anticoagulants between October 1, 2015 and September 30, 2016 (according to Part D claims). Structured medical record review was the gold standard for validating the presence of anticoagulant-related bleeding. Sensitivity was adjusted to correct for partial verification bias due to sampling design. RESULTS: Based on the study sample of 1166 records (583 cases, 583 controls), 57 of 206 codes yielded the optimal performance for anticoagulant-related bleeding (diagnostic odds ratio, 51; positive predictive value (PPV), 75.7% [95% CI, 72.0%-79.1%]; adjusted sensitivity, 70.0% [95% CI, 63.2%-77.7%]). Codes for intracranial bleeding demonstrated the highest PPV (85.0%) and adjusted sensitivity (91.0%). Bleeding codes in the primary position demonstrated high PPV (86.9%), but low adjusted sensitivity (36.0%). The adjusted sensitivity improved to 69.5% when codes in a secondary position were added. Only one adverse effect/poisoning code was used, appearing in 7.8% of cases and controls (PPV, 71.4% and adjusted sensitivity, 6.8%). CONCLUSIONS: Performance of ICD-10-CM code assignments for bleeding among patients prescribed anticoagulants varied by bleed type and code position. Adverse effect/poisoning codes were not commonly used and would have missed over 90% of anticoagulant-related bleeding cases.