Table 2

HRs for CVDs or total mortality and baseline or updated mean A1C in 7,454 patients with type 1 diabetes followed for 5 years

Patients n/events n/event rate (%)*Baseline A1C as predictorUpdated mean A1C as predictor
HR (95% CI)HR (95% CI)HR (95% CI)HR (95% CI)
A1C per 1% unit increase
    Fatal/nonfatal CHD
        All patients7,454/131/2.01.31 (1.12–1.52)§1.28 (1.09–1.49)1.34 (1.14–1.58)§1.30 (1.10–1.53)
        Duration 1–20 years3,763/25/0.81.49 (1.08–2.05)1.46 (1.06–2.01)1.45 (1.03–2.03)1.41 (1.01–1.97)
        Duration 21–35 years3,691/106/3.21.30 (1.10–1.54)1.27 (1.07–1.50)1.38 (1.15–1.67)§1.34 (1.11–1.62)
    Fatal/nonfatal stroke
        All patients7,454/37/0.61.12 (0.83–1.51)1.08 (0.80–1.47)1.24 (0.89–1.72)1.19 (0.86–1.66)
    Fatal/nonfatal CVD
        All patients7,454/154/2.41.26 (1.09–1.45)§1.22 (1.06–1.40)1.32 (1.14–1.54)§1.27 (1.09–1.80)
        Duration 1–20 years3,763/26/0.81.49 (1.09–2.04)1.46 (1.07–2.00)1.48 (1.06–2.07)1.44 (1.04–2.01)
        Duration 21–35 years3,691/128/4.01.23 (1.06–1.44)1.19 (1.02–1.39)1.34 (1.13–1.59)§1.29 (1.08–1.53)
    Total mortality
        All patients7,454/94/1.40.97 (0.80–1.17)0.92 (0.76–1.11)1.04 (0.85–1.28)0.98 (0.80–1.20)
A1C intervals (mean) at baseline in two patient groups
    Fatal/non-fatal CHD
        5.0–7.9% (7.2)4,186/45/1.21.01.0
        8.0–11.9% (9.0)3,268/86/2.9§1.80 (1.24–2.60)1.71 (1.18–2.48)
    Fatal/non-fatal stroke
        5.0–7.9% (7.2)4,186/14/0.51.01.0
        8.0–11.9% (9.0)3,268/23/0.8§1.51 (0.76–2.98)1.40 (0.70–2.79)
    Fatal/non-fatal CVD
        5.0–7.9% (7.2)4,186/55/1.61.01.0
        8.0–11.9% (9.0)3,268/99/3.3§1.70 (1.21–2.38)1.59 (1.13–2.24)
  • HRs for CVDs per 1% unit increase in A1C, or with a patient group with A1C at baseline 8–11.9%, compared with another group with A1C at baseline 5–7.9%, when followed for 5 years.

  • *Mean event rates in a Cox model adjusted as in model 2.

  • †Model 1: adjusted for age, sex, diabetes duration, systolic blood pressure, total cholesterol, LDL cholesterol, triglycerides, BMI, smoking, and a history of CVD.

  • ‡Model 2: adjusted as in model 1 and also for albuminuria (>20 μg/min). Significance level for the difference between two mean log event rates and for HRs.

  • §P < 0.001;

  • P < 0.01;

  • P < 0.05.