Continuous glucose monitoring abnormalities in cystic fibrosis youth correlate with pulmonary function decline.

BACKGROUND: To characterize glucose patterns with continuous glucose monitoring (CGM) in cystic fibrosis (CF) and assess relationships between CGM and clinical outcomes.

METHODS: 110 CF youth and healthy controls (HC), 10-18 years, wore CGM up to 7 days. Correlations between CGM and lung function and BMI z-score change over the prior year were determined.

RESULTS: Multiple CGM measures were higher in CF Normal Glycemic (CFNG) youth versus HC (peak glucose, excursions >140 mg/dl/day, %time > 140 mg/dl, standard deviation (SD) and mean amplitude of glycemic excursions (MAGE)). Hypoglycemia was no different among groups. In CF, decline in FEV1% and FVC% correlated with maximum CGM glucose, excursions >200 mg/dl/day, SD, and MAGE.

CONCLUSIONS: CFNG youth have higher glucoses and glucose variability than HC on CGM. Higher and more variable glucoses correlate with lung function decline. Whether earlier treatment of CGM abnormalities improves lung function in CF requires further study.