Table 2

Progression of eGFR as a function of the category of AER in the DCCT/EDIC study (n = 1,439) based on the current AER value or the history of AER values

ModelsEffectNumber with event (n = 89)Patient-yearsRate per 1,000 patient-yearsCox proportional hazard model*GLMM§
Hazard ratio (95% CI)Pair-wise P value% Decrease per year (95% CI)Pair-wise P value
M vs. NM vs. N
Current albuminuria modelNormal (N)3028,1231.11<0.00011.2% (1.2–1.3)<0.0001
A vs. MA vs. M
    Albuminuria category defined from the AER value at the time of estimated GFR assessmentMicroalbuminuria (M)184,0414.43.3 (1.8–6.1)<0.00011.8% (1.6–1.9)<0.0001
A vs. NA vs. N
Macroalbuminuria (A)4183746.715.3 (8.9–26.3)<0.00015.7% (4.5–6.8)<0.0001
M vs. NM vs. N
History of albuminuria modelNormal (N)2121,0691.010.2811.2% (1.2–1.3)0.0007
A vs. MA vs. M
    Albuminuria category defined from the highest AER value observed before or at the time of estimated GFR assessmentMicroalbuminuria (M)1410,4921.30.7 (0.4–1.4)<0.00011.4% (1.3–1.4)<0.0001
A vs. NA vs. N
Macroalbuminuria (A)541,44036.18.6 (5.0–14.7)<0.00015.1% (4.0–6.2)<0.0001
  • Crude risk of developing sustained estimated GFR <60 ml/min/1.73 m2 (or ESRD) and the relative risk (hazard ratio) estimated from the Cox proportional hazards model are shown. Mean of the rate of decline (% decrease per year) in estimated GFR was obtained from the general linear mixed model.

  • *Cox proportional hazard model of the time from DCCT randomization to the initial sustained eGFR <60 ml/min/1.73 m2 through EDIC year 14, after adjustment for mean arterial pressure and ACE inhibitor use versus not at each visit as time-dependent covariates. For those with a missing covariate value at a visit, the prior observed value was carried forward. Mean arterial pressure was computed as (2/3 diastolic blood pressure + 1/3 systolic blood pressure). ACE inhibitor use was proscribed during DCCT (1983–1993).

  • †The 89 patients with events are subjects with sustained eGFR <60 ml/min/1.73 m2.

  • ‡For each patient, patient-years is calculated as the elapsed whole years from randomization into the DCCT to either the visit at which a sustained eGFR <60 ml/min/1.73 m2 was first observed or the last visit at which the eGFR was measured if a patient had no event during the time.

  • §Percent decrease in eGFR per year while in each category of albuminuria obtained from the generalized linear mixed model of log-transformed levels of eGFR as a function of time, with heterogeneous random intercept, random slope over time, and residual errors among the time-dependent AER categories, after adjustment for time-dependent use of ACE inhibitor and time-dependent mean blood pressure at each DCCT-EDIC visit. For subjects with a missing covariate (AER, ACE inhibitor use, or mean blood pressure) at a visit, the prior observed value was carried forward. For subjects reaching ESRD, an eGFR value of 15 ml/min/1.73 m2 was assigned thereafter for annual visits.