Table 1

Characteristics of the cohorts included in the study

StudyNSpectrometerSF measureGenotyping platformCovariates
T1D
 DCCT/EDIC1,082SCOUT DSSIFIllumina 1MAge, sex, skin tone, clinic latitude, eGFR, smoking status, rs1495741 genotype*
 WESDR281SCOUT DSSIFIllumina Omni-quadAge, sex, skin tone, eGFR, smoking status, rs1495741 genotype
ND plus T2D
 LonGenitySCOUT DSSIFIllumina HumanOmniExpressAge, sex, skin tone, eGFR, smoking status
  ND (OPEL)192
  ND (OPUS)261
  T2D58
 LifeLinesAGE ReaderSAFIllumina CytoSNP 12v2Age, sex, BMI, eGFR, smoking status, 10 first principle components§
  ND8,678
  T2D318
  • *Clinic latitude: categorized as a binary variable, with clinic located above 37° N latitude designated as northern clinics. eGFR: mean eGFR trough DCCT/EDIC calculated using annually measured serum creatinine and the Chronic Kidney Disease Epidemiology Collaboration equation (35). Smoking status during EDIC years 1–5, 6–10, and 11–16 as a continuous variable calculated by summing smoking status.

  • †eGFR: mean eGFR calculated using serum creatinine, measured almost every 5 years, and the Chronic Kidney Disease Epidemiology Collaboration equation (35). Smoking status: mean of smoking status, asked every 5 years through the study.

  • ‡eGFR: eGFR calculated using serum creatinine and the Chronic Kidney Disease Epidemiology Collaboration equation (35). Smoking status: smoker vs. nonsmoker.

  • §eGFR: Cockcroft-Gault eGFR. Smoking status: smoker vs. nonsmoker.