Impact of neighbourhood-level inequity on paediatric diabetes care.

Abstract

To evaluate the association between neighbourhood-level inequity and glycaemic control in paediatric participants with Type 1 diabetes using the Neighbourhood Equity Index (NEI). The NEI was linked to the clinical data of 519 children with diabetes followed at the Hospital for Sick Children (Toronto, Canada). The NEI is a composite measure of inequity developed using the World Health Organization's Urban Health Equity Assessment and Response Tool (HEART), which encompasses 15 weighted indicators evaluating economic, social, environmental and lifestyle factors. The geographic distribution of participants was determined using postal codes, and the relationship between HbA1c and NEI was evaluated using regression and spatial analysis techniques. Participants' mean HbA1c was significantly correlated with NEI (R = -0.24, P < 0.0001). Regression analysis demonstrated that NEI was a strong predictor of mean HbA1c (P < 0.0001), accounting for differences in HbA1c as large as 1.0% (11 mmol/mol) when controlled for age, sex, diabetes duration, insulin pump therapy and number of annual clinic visits. Geo-mapping using spatial scan testing revealed the presence of two clusters of low-equity neighbourhoods containing 3.22 (P = 0.001) and 2.83 (P = 0.02) times more participants with HbA1c ≥ 9.5% (80 mmol/mol) than expected. Our findings demonstrated that NEI was a significant predictor of HbA1c in our clinic population and a useful tool for investigating spatial trends related to inequities in health, providing evidence that a composite, area-based measure of overall inequity is well suited to the study of glycaemic control in urban paediatric Type 1 diabetes populations.