Effect of the historic Spanish heatwave over glycemic control in adult patients with type 1 diabetes

To evaluate the effect of the historic Spanish heatwave (9th–26th July 2022) over glycemic control in adults with type 1 diabetes (T1D). Cross-sectional retrospective analysis of adult patients with T1D in Castilla-La Mancha (south-central Spanish region) using intermittently scanned continuous glucose monitoring (isCGM) during and after the heatwave. Primary outcome was change in time in range (TIR) 3.0–10 mmol/L (70–180 mg/dL) of interstitial glucose in the two weeks following the heatwave. A total of 2701 T1D patients were analyzed. We detected a TIR reduction of 4.0 % (95 % CI −3.4, −4.6; P 13 scans/day) during the heatwave showed the greatest deterioration in TIR after it concluded (−5.4 % [95 % CI −6.5, −4.3; P