Surgical treatment of diabetic foot: a spatial analysis, Ceará, Brazil, 2016-2021

To identify the spatial pattern of surgical treatment of diabetic foot complications in Ceará.

This was an observational spatial analysis study conducted in Ceará. We calculated the annual incidence rate of diabetic foot surgery. This rate was standardized with the indirect method using the mean year (2018). Subsequently, the rate was smoothed using the local empirical Bayes method. Furthermore, the Getis-Ord Gi* technique was applied to identify clustered areas of high incidence. Finally, a purely spatial scan was performed to identify relative risk (RR) for each municipality in Ceará, with those with a RR>1 presenting a higher risk for the event of interest.

Between 2016 and 2021, 7,319 hospitalizations for surgical treatment of complicated diabetic foot were recorded in Ceará, especially in the Fortaleza macro-region (49.8%; n=3,650). In the spatial analysis, both the crude rates, as well as the rates after local empirical Bayes smoothing, show greater concentration in the following macro-regions: Fortaleza, Sertão Central, Sobral and Cariri. This information was confirmed by local Moran's I and the Getis-Ord Gi* statistic (p-value <0.05). The scan revealed that 30.5% (n=56) of the state's municipalities presented RR>1.

The study revealed a spatial pattern marked by concentration of diabetic foot surgical treatment cases in the Fortaleza macro-region and, after Bayes smoothing, revealed a shift in the distribution of cases to two of the state's interior-region municipalities, Quixadá and Aracoiaba.