Racial factors and inpatient outcomes among patients with diabetes hospitalized with foot ulcers and foot infections, 2003-2014

Background In patients with diabetes, foot amputations among Black patients have been historically higher compared with White patients. Using the National Inpatient Sample database, we sought to determine if disparities in foot amputations and resource utilization have improved over time. We hypothesized there would be improvements and reduced differences in foot amputations between the two races as quality of care and access to healthcare has improved. Methods and findings Patients over 18 years old with a principal diagnosis of diabetic foot complications and secondary diagnosis of Diabetes Mellitus were selected. We compared the primary outcome of foot amputations between Black and White patients. Adjusted rates, odds ratios (aOR) and trends of foot amputations among Black and White patients were studied. Healthcare utilization was measured via length of hospital stay (LOS). Of 262,924 patients, 18% were Black. Following adjustment for confounders, major foot amputations decreased among Whites (1.5% in 2003 to 1.1% in 2014) and Blacks (2.1% in 2003 to 0.9% in 2014). On pooled analysis, Black patients had higher adjusted odds of major foot amputations in 2003-2004 [aOR 1.7; (1.16-2.57), p<0.01]. Disparities in major foot amputations disappeared in 2013-2014 [aOR: 0.92 (0.58-1.44), p = 0.70]. Black patients had declining but persistently longer LOS (adjusted mean difference (aMD): 1.1 days (0.52-1.6) p<0.01 in 2003-2004 and 0.46 days (0.18-0.73) p<0.01 in 2013-2014). The main limitation of the study was that the NIS uses ICD-9 and ICD-10 CM codes, and hence prone to incorrect or missing codes. Conclusions Major foot amputations declined among Black and White patients hospitalized with Diabetic foot complications between 2003 and 2014. The observed difference for amputations in 2003-2004 was absent by 2013-2014. Future research to determine specific contributors for this reduction in health disparities is needed for ongoing improvements and sustainability.