Evaluación del tiempo por debajo del rango como predictor de hipoglucemia grave: perspectivas de seis ensayos...

To evaluate whether baseline continuous glucose monitoring (CGM)-derived time below range (TBR) metrics-TBR level 1 (TBR1) (<70 mg/dL) and TBR level 2 (TBR2) (<54 mg/dL)-predicts severe hypoglycemia (SH) during follow-up of individuals with type 1 diabetes.

Baseline CGM TBR levels and their association with SH adverse events during six clinical trials were analyzed using Wilcoxon rank-sum tests and Spearman correlations. Analyses were stratified by sex, race, and age group. Sensitivity, specificity, and false-positive rates (FPRs) were calculated for thresholds (1-5%), and receiver operating characteristic (ROC) analysis assessed discrimination.

Participants (n = 1,433; median age 4-43 years; 50-62% female sex; 83-96% White race) had a baseline median TBR2 range of 0.1% to 0.7% and TBR1 from 1.2% to 4.1% across the six clinical trials. Those who developed SH had slightly higher baseline TBR2 (0.41% vs. 0.32%; P = 0.022) and TBR1 (2.58% vs. 2.23%; P = 0.044). Predictive accuracy was limited: sensitivity of TBR2 fell from 48.9% at a 1% cutoff to 18.2% at 5% (specificity 75.9-95.0%), and TBR1 sensitivity declined from 81.8% to 44.3% (specificity 29.6-77.7%), with modest discrimination by ROC analysis (area under the curve = 0.62 [95% CI 0.55-0.69] for TBR2; and 0.65 [95% CI: 0.58-0.71] for TBR1).

Baseline TBR1 and TBR2 had limited predictive value for SH. No threshold achieved strong discrimination, a finding that supports the need to integrate additional clinical factors for SH risk stratification.