The influence of time in range on daily mood in adults with type 1 diabetes

To investigate the impact of time in range (TIR) on mood in adults with type 1 diabetes (T1D). We followed a cohort of 219 T1D adults, all currently employing a real-time continuous glucose monitoring system (RT-CGM), to investigate how daily changes in CGM metrics were associated with nightly reports of positive and negative mood over a two-week period. Greater daily %TIR (70–180 mg/dL) and less time in “severe” hyperglycemia (% time above range (TAR) > 300 mg/dL) were both significantly associated with higher ratings on all positive mood elements and lower ratings on most negative mood elements (all ps 300 emerged as an independent predictor of many of the positive and negative mood variables. Neither daily changes in time spent in hypoglycemia (< 70 mg/dL) nor glycemic variability (represented by the coefficient of variation) were significantly related to reported mood. This study provides the first evidence that time in range (%TIR) is associated with, and likely enhances, daily mood. Consistent with previous studies, we also found that more time spent in “severe” hyperglycemia is linked to more negative mood. •Greater time each day within glucose targets (70 – 180 mg/dL), known as “time in range”, is associated with better mood.•Similarly, less time in the “severe” hyperglycemic range (> 300 mg/dL) is associated with poorer mood.•When entered together as predictors, TIR but not TAR > 300 emerged as an independent predictor of most mood variables.•Neither daily changes in time spent in hypoglycemia nor glycemic variability were significantly related to reported mood.•This study provides the first evidence that time in range is associated with, and likely enhances, daily mood.