Glycemic Variability and Fluctuations in Cognitive Status in Adults With Type 1 Diabetes (GluCog): Observational Study Using Ecological Momentary Assessment of Cognition

Abstract

Background Individuals with type 1 diabetes represent a population with important vulnerabilities to dynamic physiological, behavioral, and psychological interactions, as well as cognitive processes. Ecological momentary assessment (EMA), a methodological approach used to study intraindividual variation over time, has only recently been used to deliver cognitive assessments in daily life, and many methodological questions remain. The Glycemic Variability and Fluctuations in Cognitive Status in Adults with Type 1 Diabetes (GluCog) study uses EMA to deliver cognitive and self-report measures while simultaneously collecting passive interstitial glucose in adults with type 1 diabetes. Objective We aimed to report the results of an EMA optimization pilot and how these data were used to refine the study design of the GluCog study. An optimization pilot was designed to determine whether low-frequency EMA (3 EMAs per day) over more days or high-frequency EMA (6 EMAs per day) for fewer days would result in a better EMA completion rate and capture more hypoglycemia episodes. The secondary aim was to reduce the number of cognitive EMA tasks from 6 to 3. Methods Baseline cognitive tasks and psychological questionnaires were completed by all the participants (N=20), followed by EMA delivery of brief cognitive and self-report measures for 15 days while wearing a blinded continuous glucose monitor. These data were coded for the presence of hypoglycemia (<70 mg/dL) within 60 minutes of each EMA. The participants were randomized into group A (n=10 for group A and B; starting with 3 EMAs per day for 10 days and then switching to 6 EMAs per day for an additional 5 days) or group B (N=10; starting with 6 EMAs per day for 5 days and then switching to 3 EMAs per day for an additional 10 days). Results A paired samples 2-tailed t test found no significant difference in the completion rate between the 2 schedules (t17=1.16; P=.26; Cohen dz=0.27), with both schedules producing >80% EMA completion. However, more hypoglycemia episodes were captured during the schedule with the 3 EMAs per day than during the schedule with 6 EMAs per day. Conclusions The results from this EMA optimization pilot guided key design decisions regarding the EMA frequency and study duration for the main GluCog study. The present report responds to the urgent need for systematic and detailed information on EMA study designs, particularly those using cognitive assessments coupled with physiological measures. Given the complexity of EMA studies, choosing the right instruments and assessment schedules is an important aspect of study design and subsequent data interpretation.

Ecological Momentary Assessment of Cognition in Clinical and Community Samples: Reliability and Validity Study

“…Table S1 in Multimedia Appendix 1 provides further details on participant compliance. The exclusion criteria were decided as part of the study protocol before this analysis and have been described in our published protocol for the T1D study [ 18 ] as well as in a paper now published using data from the community sample [ 19 ].…”

“…Psychometric characteristics were evaluated for each alternate form to ensure that they had similar reliability and distributional properties. The psychometric characteristics of the individual, ultrabrief TMB tests used in this study have also been previously described, although within the context of glycemic variability in a sample of individuals with T1D [ 18 ].…”

Dynamic associations between glucose and ecological momentary cognition in Type 1 Diabetes

“…The study protocol was previously described (45). Briefly, participants provided informed consent and completed initial clinic visits prior to starting ecological momentary assessments (EMAs).…”

“…) were validated for brief administration across demographic groups (9,45). Prior to EMA, participants completed onboarding with task instructions, practice trials, and corrective feedback.…”

Reliability and Validity of Noncognitive Ecological Momentary Assessment Survey Response Times as an Indicator of Cognitive Processing Speed in People’s Natural Environment: Intensive Longitudinal Study

“…The difficulties in implementing formal ambulatory assessments limit our ability to more frequently investigate cognitive performance in everyday real-world settings in populations with chronic conditions. When considering T1D specifically, ambulatory cognitive performance has rarely been assessed [ 12 , 13 , 16 ], limiting our understanding of time-varying correlates and ultimately our understanding of the multifactorial pathways connecting diabetes to cognitive performance and decline.…”