Disparities in receipt of complete diagnostic evaluation to confirm myelodysplastic syndromes.

Abstract

7555 Background: A complete diagnostic evaluation (CDE), including bone marrow (BM) biopsy, cytogenic testing, FISH panel, and/or flow cytometry, is widely accepted as a prerequisite for histopathologic confirmation of MDS. Earlier reports have raised concerns regarding accuracy of MDS diagnosis in population registries that do not require confirmatory tests for disease reporting. We queried Medicare files to analyze the extent of use of, and factors associated with CDE for diagnosing MDS. Methods: The study population included Medicare patients with at least one inpatient or two outpatient claims for MDS within a 12-month period during the years 2012 and 2013. Variables included age, sex, race, morphologic MDS categories, cytopenias (isolated or any combination), transfusion burden, comorbididities, as well as county-level characteristics (income, educational attainment, rurality, and availability of internal medicine subspecialists). Classification and regression tree (CART) and multivariable logistic regression analysis were used to identify combinations of factors associated with receipt of CDE. Results: Our study population included 45,067 MDS patients, of whom only 68.6% received CDE that included BM biopsy and/or chromosomal studies. The percent of patients undergoing CDE was significantly lower among those 85 years of age or older (56.1%); women (63.7%); Blacks (64.2%); patients with isolated anemia (60.3%); and those who were transfusion independent (p < 0.001 for all comparisons). On the other hand, CDE was significantly higher among patients with the category of MDS with excess blasts (89.4%); those presenting with pancytopenia (92.2%); and those with high transfusion burden (80%). There was little variation by comorbidity burden, county level characteristics, or availability of subspecialists. In CART analysis, 80% of patients presenting with any two or more cytopenias received CDE. In multivariable analysis, advanced age, female sex, Black race, higher comorbidity burden and availability of subspecialists were associated with a lower likelihood to receive CDE, while patients with MDS with excess blasts, and with any > 2 cytopenias were more likely to receive CDE ( P< .0001). Conclusions: Nearly one third (31%) of MDS patients in the Medicare database lack CDE especially BM biopsy. Disparities in CDE can be corrected through proper physician education and stringent registry reporting to avoid such high diagnostic inaccuracies, leading to potential missed treatment opportunities.