Table 1

Hazard ratios for development of retinopathy and microalbuminuria outcomes according to TIR

Retinopathy outcomeMicroalbuminuria outcome
TIRNN (%) with outcomeUnadjusted HR (95% CI)*Adjusted HR (95% CI)†NN (%) with outcomeUnadjusted HR (95% CI)*Adjusted HR (95% CI)†
Overall
 ≥50%46636 (8)1.001.0041210 (2)1.001.00
 40 to <50%31932 (10)1.54 (0.94–2.55)1.61 (0.97–2.65)29120 (7)2.44 (1.05–5.67)2.40 (1.03–5.58)
 30 to <40%27159 (22)3.38 (2.22–5.15)3.37 (2.20–5.15)24229 (12)4.74 (2.16–10.40)4.39 (2.01–9.58)
 <30%384144 (38)6.23 (4.25–9.13)6.93 (4.69–10.24)33857 (17)6.68 (3.35–13.29)6.98 (3.49–13.96)
Primary cohort
 ≥50%2288 (4)1.001.002223 (1)1.001.00
 40 to <50%15910 (6)2.43 (0.91–6.53)2.43 (0.90–6.54)1534 (3)1.25 (0.19–8.41)1.24 (0.18–8.36)
 30 to <40%13125 (19)7.08 (3.09–16.23)6.51 (2.82–15.02)1236 (5)3.68 (1.00–13.47)3.61 (0.98–13.21)
 <30%20864 (31)11.29 (5.13–24.85)11.16 (5.05–24.64)20023 (12)7.35 (2.22–24.26)7.24 (2.19–23.94)
Secondary cohort
 ≥50%23828 (12)1.001.001907 (4)1.001.00
 40 to <50%16022 (14)1.30 (0.73–2.31)1.38 (0.77–2.45)13816 (12)2.91 (1.05–8.02)2.92 (1.05–8.08)
 30 to <40%14034 (24)2.39 (1.43–3.97)2.50 (1.50–4.17)11923 (19)5.11 (1.91–13.65)4.76 (1.79–12.68)
 <30%17680 (45)4.95 (3.16–7.77)5.72 (3.60–9.09)13834 (25)6.93 (2.90–16.59)6.78 (2.83–16.25)
  • Strata based on TIR averaged over the entire DCCT study period. HR, hazard ratio.

  • *From discrete Cox proportional hazards regression models. P value, computed using TIR as a time-dependent continuous variable, is <0.001 for each cohort. †From discrete Cox proportional hazards regression models stratified by the ETDRS level of retinopathy at baseline and adjusted for the pre-DCCT glycemic exposure represented by the preexisting duration of diabetes separately for the primary and secondary cohorts. P value, computed using TIR as a time-dependent continuous variable, is <0.001 for each cohort. An additional model which included age and sex as covariates produced similar results.