Reproducibility of continuous glucose monitoring results under real-life conditions in an adult population: a functional data analysis

Abstract

Continuous glucose monitoring systems (CGM) are a very useful tool to understand the behaviour of glucose in different situations and populations. Despite the widespread use of CGM systems in both clinical practice and research, our understanding of the reproducibility of CGM data remains limited. The present work examines the reproducibility of the results provided by a CGM system in a random sample of a free-living adult population, from a functional data analysis approach. Functional intraclass correlation coefficients (ICCs) and their 95% confidence intervals (CI) were calculated to assess the reproducibility of CGM results in 581 individuals. 62% were females 581 participants (62% women) mean age 48 years (range 18–87) were included, 12% had previously been diagnosed with diabetes. The inter-day reproducibility of the CGM results was greater for subjects with diabetes (ICC 0.46 [CI 0.39–0.55]) than for normoglycaemic subjects (ICC 0.30 [CI 0.27–0.33]); the value for prediabetic subjects was intermediate (ICC 0.37 [CI 0.31–0.42]). For normoglycaemic subjects, inter-day reproducibility was poorer among the younger (ICC 0.26 [CI 0.21–0.30]) than the older subjects (ICC 0.39 [CI 0.32–0.45]). Inter-day reproducibility was poorest among normoglycaemic subjects, especially younger normoglycaemic subjects, suggesting the need to monitor some patient groups more often than others.

Real World Interstitial Glucose Profiles of a Large Cohort of Physically Active Men and Women

“…This large cohort study of active males and females complements other cohort studies of CGM metrics in the general population [14][15][16][17][18] but is the first to focus on glycemia during sleep and endurance exercise. Unlike these other smaller studies, these data reveal small differences between genders in overall 24 h glycemia, with women having slightly lower 24 h mean glucose levels as well as lower glucose levels in response to meals and sleep than men.…”

Imprecision nutrition? Duplicate meals result in unreliable individual glycemic responses measured by continuous glucose monitors across four dietary patterns in adults without diabetes

“…Our participants were representative of a generally healthy population across a wide range of body mass indexes, but without diabetes or other metabolic disease. Recent cross-sectional evidence using Medtronic devices suggests day-to-day reproducibility of CGM readings is lower in younger individuals (< 60 years) without prediabetes or type 2 diabetes (33). Intriguingly, we found a low mean bias of within-subject iAUCs in response to multiple pairs of duplicate meals suggesting that it may be possible to reliably estimate within-subject postprandial responses to the same meals provided that enough repeated measurements are made.…”

Innovative Solution or Cause for Concern? The Use of Continuous Glucose Monitors in People Not Living with Diabetes: A Narrative Review.

“…The available studies on CGM accuracy in PNLD exhibit overarching limitations, including small and unrepresentative sample sizes, [21][22][23][24][25]28 use of outdated device models [27][28] and low generalisability. Analysis is rarely supported with confidence intervals, thereby effect size, precision and reliability of the findings are uncertain.…”

“…26 CGM measurements also suffer from lower inter-day reproducibility in PNLD, especially among younger individuals as established using functional data analysis. 27 This emphasizes the need for rigorous calibration processes and precise reference standards to compile best practice guidelines ensuring reliability of CGM outputs. For PNLD, this aspect is visibly amiss.…”