Demographics and symptoms of the study population at baseline and at last available OGTT.

Data are median with lower and upper quartile for continuous variables, and percentage for dichotomous variables. For patients ≤18 years, standard deviation scores are shown for height, weight and body mass index. Weight and height measurements (and thereby body mass index, percentage underweight) were missing in few patients. Abbreviations: OGTT = oral glucose tolerance test, SDS = standard deviation score.