|Authors||Koivula, R.W., Forgie, I.M., Kurbasic, A., Viñuela, A., Heggie, A., Giordano, G.N., Hansen, T.H., Hudson, M., Koopman, A.D., Rutters, F., Siloaho, M., Allin, K.H., Brage, S., Brorsson, C.A., Dawed, A.Y., De Masi, F., Groves, C.J., Kokkola, T., Mahajan, A., Perry, M.H., Rauh, S.P., Ridderstråle, M., Teare, H.J.A., Thomas, E.L., Tura, A., Vestergaard, H., White, T., Adamski, J., Bell, J.D., Beulens, J., Brunak, S., Dermitzakis, E.T., Froguel, P., Frost, G., Gupta, R., Hansen, T., Hattersley, A., Jablonka, B., Kaye, J., Laakso, M., McDonald, T.J., Pedersen, O., Schwenk, J.M., Pavo, I., Mari, A., McCarthy, M.I., Ruetten, H., Walker, M., Pearson, E. and Franks, P.W.|
Objectives: Here, we describe the characteristics of the IMI DIRECT (Diabetes Research on Patient Stratification) epidemiological cohorts at baseline and follow-up examinations (18, 36 and 48 month follow-up).
Research design and methods: From a sampling-frame of 24,682 European-ancestry adults enrolled in population-based cohorts across Europe, participants at varying risk of glycaemic
deterioration were identified using a risk prediction algorithm (based on age, BMI, waist circumference, smoking status and family history of type 2 diabetes) and enrolled into a prospective cohort study (n=2127) (Cohort 1: prediabetes risk). We also recruited people from clinical registries with type 2 diabetes diagnosed 6 to 24 month prior (n=789) into a second cohort study (Cohort 2: diabetes). The cohorts were studied in parallel using matched protocols across seven clinical centres in northern Europe.
Results: Using ADA-2011 glycaemic categories, 33% (n=693) of Cohort 1 (prediabetes risk) had normal glucose regulation (NGR), and 67% (n=1419) had impaired glucose regulation
(IGR). 76% of the cohort was male; age=62(6.2) years; BMI=27.9(4.0) kg/m2; fasting glucose=5.7(0.6) mmol/l; 2-hr glucose=5.9(1.6) mmol/l [mean(SD)]. At follow-up,
examinations took place ~18 and ~48 months after baseline; fasting glucose=6.0(0.6) mmol/l;2-hr OGTT glucose=6.5 (2.0) mmol/l [mean(SD)] at final follow-up. In Cohort 2 (diabetes):
65% (n=508) were lifestyle treated (LS) and 35% (n=271) were lifestyle + metformin treated(LS+MET) at enrolment. 58% of the cohort was male; age=62(8.1) years; BMI=30.5(5.0)
kg/m2; fasting glucose=7.2(1.4)mmol/l; 2-hr glucose=8.6(2.8) mmol/l [mean(SD)]. At follow-up, examinations took place ~18 and ~36 months after baseline; fasting glucose=7.9(2.0) mmol/l; 2-hr MMTT glucose=9.9(3.4) mmol/l [mean(SD)] at final followup.
Conclusions: The IMI DIRECT cohorts are intensely characterized with a wide variety of metabolically relevant measures assessed prospectively. The cohorts aim to provide a
powerful resource for biomarker discovery, multivariate aetiological analyses and reclassification of patients for the prevention and treatment of type 2 diabetes.