Chronic exposure to glucocorticoids (GCs) has many side effects including glucose intolerance and diabetes and may accelerate the occurrence of cardiovascular disease and increase mortality. We studied the 14-year clinical development of diabetes in patients diagnosed with diabetes during GC treatment. A population-based sample of 1369 people newly diagnosed with clinical type 2 diabetes underwent a clinical examination at diagnosis, and surviving patients were followed up 6 and 14 years later. Patients receiving oral GC treatment at diagnosis were compared with the other patients. Of 1369 patients, 35 (2.6%) were treated with oral GCs at diabetes diagnosis. At that point, patients on GC therapy were older (69.9 versus 65.3 years, p = 0.007, sex-adjusted) and tended to have lower BMI (26.1 versus 29.1 kg/m(2) , p = 0.023), also 6 years after diagnosis (24.8 versus 28.4, p = 0.011), than patients not being treated with GCs. In a univariate Cox regression model, GC treatment at diagnosis increased all-cause mortality with a hazard ratio (95% confidence interval) of 2.01 (1.39-2.89, p = 0.0002, n = 1369), while this decreased to 1.41 (0.98-2.04, p = 0.065, n = 1369) when adjusted for age and sex and to 1.39 (0.92-2.11, p = 0.12, n = 1086) when risk factors, complications and cancer were added to the model. Apart from differences in age and overweight, patients in this relatively small sample of those diagnosed with clinical type 2 diabetes during GC treatment were comparable at diagnosis and during 14 years of follow-up with those not treated with GCs, including with regard to the adjusted mortality rate