In a study published in the International Journal of Diabetes and Technology, the investigators evaluated a novel continuous glucose monitoring (CGM)–derived metric, the social/typical (ST) ratio, defined as (interventile range − interquartile range)/interquartile range, to characterize between-day glycemic variability in type 1 diabetes (T1D). The ST ratio was calculated across total (0000–2400), daytime (0600–2400), and nighttime (0000–0600) periods in two datasets: (i) a randomized controlled exercise intervention study in overweight adults and (ii) an observational cohort of older adults with frequent severe hypoglycemia.

In cohort (i) at baseline, higher total ST was observed in participants with nephropathy (P=0.013), and higher nighttime ST in those with retinopathy (P=0.009). Nighttime ST increased following exercise intervention (1.04 ± 0.27 to 1.44 ± 0.52; P=0.008). Total ST correlated positively with time below range after intervention (r=0.480; P=0.018). In cohort (ii), total ST correlated positively with time in range (r=0.320; P<0.001) and negatively with time above range (r=−0.277; P<0.001). Higher coefficient of variation, but not ST, was associated with recent severe hypoglycemia (P=0.014).

Limitations include small sample sizes, observational and post hoc analyses, use of different CGM systems, inability to account for meal or sleep timing, and limited generalizability to broader T1D populations.

The ST ratio was associated with established glycemic metrics and microvascular complications in these cohorts. Larger, diverse datasets are needed to assess reproducibility and clinical applicability.