To the Editor In an observational study of almost 100 000 adults, Dr Xu and colleagues1 provided alarming estimates of the burden of diabetes and prediabetes in China. The authors estimated that in 2010, more than 113 million Chinese adults had diabetes and close to 500 million had prediabetes.
When directly compared with Chinese prevalence data from 2007,2 there has been a 20% increase in the prevalence of diabetes (from 9.7% in 2007 to 11.6% in 2010) and a 223% increase in the prevalence of prediabetes (from 15.5% to 50.1%). However, in our opinion the observed increase in both the prevalence of diabetes and prediabetes from 2007 to 2010 is an artifact explained by (1) adding the HbA1c criterion to the diagnosis of diabetes and (2) using the lower diagnostic threshold for impaired fasting glucose of 100 mg/dL instead of 110 mg/dL.
Færch K, Vistisen D. Prevalence of Diabetes in Chinese Adults. JAMA. 2014;311(2):200. doi:10.1001/jama.2013.283127