Table 1

Clinical characteristics of the DCCT/EDIC study cohort by treatment group assignment at DCCT baseline (1983–1989) and by the 30th year of DCCT/EDIC study follow-up (2013)

DCCT baseline (1983–1989)Average over DCCT/EDIC
Intensive treatment(N = 711)Conventional treatment(N = 730)P value*Intensive treatment(N = 711)Conventional treatment(N = 730)P value*
ProtocolCohort (% primary prevention)49520.2818
Demographic
 PhysicalSex (% women)49460.3169
Age (years)27 ± 727 ± 70.138341 ± 840 ± 80.0141
Adult (%)87860.5162
Weight (kg)
 Men73.8 ± 10.875.8 ± 11.70.009189.0 ± 10.683.9 ± 10.8<0.0001
 Women62.7 ± 8.662.1 ± 9.50.296674.3 ± 9.570.4 ± 9.4<0.0001
BMI (kg/m2)
 Men23.4 ± 2.623.9 ± 2.90.004527.7 ± 2.826.6 ± 2.9<0.0001
 Women23.3 ± 2.822.9 ± 2.90.061027.3 ± 3.226.0 ± 3.2<0.0001
 BehavioralCurrent cigarette smoker (%)19180.971817170.9982
Occasional or regular drinker (%)21220.485239410.3492
Moderate or strenuous activity (%)70690.688056560.9455
 Family historyFamily history (%)
 Hypertension57560.8445
 Myocardial infarction48490.6459
 Type 1 diabetes14140.8025
 Type 2 diabetes1080.4238
Traditional
 Blood pressureSystolic (mmHg)113 ± 12115 ± 120.0116119 ± 8119 ± 90.4321
Diastolic (mmHg)72 ± 973 ± 90.257474 ± 574 ± 50.7303
Pulse pressure (mmHg)41 ± 1042 ± 100.063945 ± 645 ± 60.3492
 Pulse rateRate (bpm)76 ± 1176 ± 110.726972 ± 773 ± 70.0094
 LipidTotal cholesterol (mg/dL)177 ± 33176 ± 340.5289181 ± 25183 ± 250.1216
Triglycerides (mg/dL)81 ± 4382 ± 510.815172 ± 2777 ± 270.0002
HDL cholesterol (mg/dL)51 ± 1250 ± 120.504856 ± 1156 ± 110.7699
LDL cholesterol (mg/dL)110 ± 29109 ± 290.4967108 ± 22109 ± 220.2948
Diabetes related
 HistoryDuration of diabetes (years)6 ± 45 ± 40.144120 ± 519 ± 50.0108
Stimulated C-peptide (nmol/L)
 Duration <60 months0.16 ± 0.130.16 ± 0.130.5482
 Duration ≥60 months0.04 ± 0.030.04 ± 0.040.0689
eGDR7.4 ± 1.87.3 ± 1.90.3798
 GlycemiaHbA1c (%)9.1 ± 1.69.1 ± 1.60.55427.8 ± 1.08.5 ± 1.0<0.0001
HbA1c (mmol/mol)75.8 ± 17.475.5 ± 17.961.5 ± 10.469.0 ± 10.5
  • Data are reported as the mean ± SD or %. eGDR, estimated glucose disposal rate. Boldface type indicates P values that are significant at the P < 0.05 level.

  • *At DCCT baseline, treatment group comparisons were made using the Wilcoxon rank sum test or the χ2 test. For characteristics repeated over time (e.g., weight or percentage of smokers), the average mean or prevalence over 30 years of DCCT/EDIC study annual follow-up was computed using longitudinal generalized estimating equations (GEEs) for repeated measures. SDs were estimated from the SEs using the following equation, SD = SE*SQRT(N). The SDs are smaller during the DCCT/EDIC study follow-up period owing to the larger amount of information in the longitudinal models.

  • †Cohort, sex, adult, and family history are fixed baseline characteristics. C-peptide level data were not collected during the EDIC study. Waist data used to calculate eGDR were not measured during the DCCT.

  • ‡Age and duration were not evaluated using longitudinal GEE models because each is a function of time itself. Instead, the average age and duration were computed for each subject over that subject’s length of follow-up. The average mean value over all subjects and its SD are presented. Treatment group comparisons were made using the Wilcoxon rank sum test.

  • ‖Data for men were based on 366 intensive treatment and 395 conventional treatment participants; data for women were based on 345 intensive treatment and 335 conventional treatment participants.

  • ¶Data for duration <60 months based on 412 intensive treatment and 443 conventional treatment participants; data for duration of ≥60 months based on 299 intensive treatment and 287 conventional treatment participants.