The diagnosis rate of type 1 diabetes cases is rapidly increasing, but scientists are unsure of what’s driving the change. Many have questioned if changes in the environment or lifestyle have impacted the disease.
In a newly released paper published in The Lancet Diabetes & Endocrinology, faculty from the Colorado School of Public Health examined whether environmental exposures explain why type 1 diabetes is on the rise.
The researchers looked at the prevalence of exposures, like air pollution, diet, childhood obesity, duration of breastfeeding, infections, and the introduction of cow’s milk, over time while varying their annual increase under simulated scenarios.
The simulated scenarios showed that an environmental factor that increased at a constant rate from nearly absent in the population to nearly ubiquitous would have to confer a relative risk of 5 to explain the observed 3 percent annual increase in type 1 diabetes incidence. However, most of the factors reviewed had a relative risk of less than 2.
“While several factors have been associated with type 1 diabetes, none of the associations are of a magnitude that can explain the rapid increase in incidence alone,” lead author Dr. Jill Norris said. “Moreover, evidence of the changing prevalence of these same exposures over time is not convincing nor consistent.”
The paper concludes that it is possible that multiple factors may account for the increase in type 1 diabetes cases. Other factors may be that the magnitude of observed associations has been underestimated due to measurement error or mismodeling of exposure-time-response relationships.Friday Letter Submission, Publish on February 14