Diabetes endpoint
We defined our diabetes endpoint as the first occurrence of a hospitalisation with a principal or secondary diagnosis for diabetes (ICD-9 diagnostic code 250; ICD-10 codes E10, E11, E12, E13, E14) or a prescription for insulin or an oral antidiabetic medication. These were most likely to be incident cases, as most patients admitted for a cardiovascular event would have been screened for diabetes, and anyone with a diabetes diagnosis at that hospital admission was excluded. Using hospital discharge data to capture diabetes was previously evaluated to have 90% sensitivity and 92% specificity in the Canadian province of Ontario.16