Association of type 1 diabetes and concentrations of drinking water components in Newfoundland and Labrador, Canada

• Published in: BMJ Open Diabetes Research & Care
• Main Authors: Chafe, Roger, Aslanov, Rana, Sarkar, Atanu, Gregory, Peter, Comeau, Alex, Newhook, Leigh Anne
• Other Authors: Janeway Hospital Research Foundation, Harris Centre RBC Drinking Water and Outreach Research Fund
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMJ 2018
• Subjects: Newfoundland
• Online Access: http://dx.doi.org/10.1136/bmjdrc-2017-000466; https://syndication.highwire.org/content/doi/10.1136/bmjdrc-2017-000466

Objective To determine the association between drinking water quality and rates of type 1 diabetes in the Newfoundland and Labrador (NL) population, which has one of the highest incidences of type 1 diabetes reported globally. Research design and methods The study used a community-based, case-control design. We first calculated incidence rates of type 1 diabetes at the provincial, regional and community levels. The connection between incidence rates and components in public water supplies were then analyzed in three ways: to evaluate differences in water quality between communities with and without incident cases of type 1 diabetes, and to analyze the relationship between water quality and incidence rates of type 1 diabetes at both the community and regional levels. Results The provincial incidence of type 1 diabetes was 51.7/100 000 (0-14 year age group) for the period studied. In the community-based analysis, there were significant associations found between higher concentrations of arsenic (β=0.268, P=0.013) and fluoride (β=0.202, P=0.005) in drinking water and higher incidence of type 1 diabetes. In the regional analysis, barium (β=−0.478, P=0.009) and nickel (β=−0.354, P=0.050) concentrations were negatively associated with incidence of type 1 diabetes. Conclusions We confirmed the high incidence of type 1 diabetes in NL. We also found that concentrations of some components in drinking water were associated with higher incidence of type 1 diabetes, but no component was found to have a significant association across the three different levels of analysis performed.