Patient Perspectives and Experiences From Participation in the Glycemic Excursion Minimization Prediabetes Intervention: A Qualitative Study

Abstract

Purpose

Of the 88 million American adults with prediabetes, 1.5 million transition to type 2 diabetes annually. Lifestyle changes could delay progression to type 2 diabetes development. Glycemic Excursion Minimization/Glucose Everyday Matters (GEM) is a self-guided intervention that empowers individuals via a guide paired with a continuous glucose monitor and activity monitor to understand how dietary and activity choices impact their blood glucose excursions. This qualitative study aimed to explore participant perspectives and experiences of GEM.

Design

Semi-structured qualitative interviews.

Setting

The study was conducted at an urban medical center. Interviews took place via HIPAA compliant Zoom.

Participants

Participants from a larger clinical trial who completed the GEM intervention for prediabetes (n = 16).

Method

Interviews were audio-recorded and transcribed. Using two coders, iterative cycles of inductive thematic analysis was performed to yield overarching themes related to the GEM guide and intervention.

Results

Analysis of 16 interviews revealed five major themes which highlighted the positive outcomes in health status, disease insight and support experienced during the GEM trial.

Conclusion

Key findings included increased knowledge on the relationship between lifestyle choices and glucose excursions, and positive insight on the GEM intervention and its components. Feedback from this study will be incorporated into further adoption of the GEM intervention for a prediabetes population.

Keywords

prediabetes qualitative research diabetes technology lifestyle intervention

Purpose

Diabetes mellitus is a significant global health problem associated with immense healthcare and societal costs, early death and morbidity that has tripled in prevalence over the last 20 years globally and can be largely attributed to decline in nutritional quality and increases in sedentary behavior.¹ Prevalence of prediabetes is similarly rising, affecting 352 million individuals worldwide and 88 million adults in the US, with 1.5 million Americans transitioning to type 2 diabetes (T2D) annually.² Measures to prevent or delay this transition from prediabetes to T2D have the potential to significantly reduce healthcare costs and reduce mortality and morbidity for many individuals.

Currently, the mainstay of prediabetes treatment consists of intensive lifestyle interventions and/or pharmacological therapies. Intensive lifestyle interventions are highly cost effective and conventionally involve at least 7% weight loss and 150 minutes per week of moderate to vigorous physical activity for at least a year, as outlined by the National Diabetes Prevention Program.^5,6 This principle of weight loss and moderate to vigorous physical activity has been shown to prevent, delay and treat the progression of prediabetes to T2D.^7,8 However, weight loss interventions are inappropriate for individuals with lower BMI.⁹ Prior qualitative research has found that intensive interventions focused on dietary and activity changes encounter barriers with motivation, family support, financial constraints and social expectations.^10-12 Harcke et al¹³ similarly found that support is needed for managing prediabetes. They also found that persons with prediabetes had varied perspectives of the severity of the disease, with some considering it a high priority due to the risk of developing type 2 diabetes, and others seeing it as no concern compared other more important life events or diseases.

Another mainstay of treatment for prediabetes is pharmacotherapy. Metformin, a medication classically used to prevent the transition from prediabetes to T2D, has similar potential to prevent or delay incidence of T2D compared to an intensive lifestyle intervention and could be more sustainable long-term.^14,15 However, some patients experience adverse effects including anemia, B12 deficiency, neuropathy and decline of cognitive function.^16-19 Other medication classes such as thiazolidinediones, alpha glucosidase inhibitors, GLP-1 agonists, insulin and lipase inhibitors have been studied with both various degrees of efficacy in prediabetes and additional side effects and costs.^20-24

For T2D, it has been demonstrated that a lifestyle intervention, Glycemic Excursion Minimization or Glucose Everyday Matters (GEM), that reduces post-nutrient glycemic excursions (area under the curve of glucose concentration over time – AUC) is an effective strategy for treatment in comparison to weight loss-focused lifestyle management.^25-28 GEM was also found to be more effective than weight loss alone in reducing A1C values, consumption of high-glycemic-load carbohydrates, glycemic excursions >140 mg/dl, depression symptoms, diabetes distress and BMI in a sample of adults newly diagnosed with T2D.²⁹ This T2D GEM study used three key elements: continuous glucose monitors (CGM) as an empowerment tool to help patients understand the effect of dietary and physical activity on glycemia, activity monitoring (using a Fitbit) and a GEM lifestyle pocket guide developed by Dr. Daniel J. Cox, PhD.²⁹

The GEM pocket guide is a small 4.25 × 5.50-inch booklet with four individual units and is designed with the philosophy that GEM is not a behavior modification program but an empowerment program that provides information that a patient can choose to implement and identify food and activity choices that exacerbate or diminish post-nutrient glycemic excursions.²⁹ It has been shown previously to be related to better diabetes knowledge, medication adherence and improved self-care behaviors.³⁰ Descriptions of each unit of the GEM guide can be found in Table 1.

Table 1.

GEM Guide Units

Unit	Title	Description
Unit 1	Impact of routine choices	With CGM feedback, participants spend 5 days learning the impact of routine nutritional and activity choices on glycemic excursions. Contains diaries to record meals, activity and effect on blood glucose
Unit 2	Revving up my engine	For 14 days, participants learn to hasten recovery of glycemic excursions through modifying physical activity type, duration and/or intensity. Contains diaries to record exercise activities and effect on blood glucose
Unit 3	Fueling up	For 14 days, participants learn about dietary modifications and strategies for reducing high-impact carbohydrate consumption to reduce glycemic excursions. Contains diaries to record meals and effect on blood glucose
Unit 4	Keeping a steady course	This unit focuses on continuing aforementioned lessons and strategies to maintain these lessons through fatigue, life changes and how to sustain support of significant others

Based on the above GEM program success in patients with T2D (including newly diagnosed with mean T2D duration of 3.9 months), we adapted the GEM guide for a prediabetes population and conducted a feasibility pilot study to determine if this strategy could be used with patients with prediabetes. This qualitative study aimed to understand a subset of participants’ experiences and feedback while participating in the first study exploring use of GEM in a prediabetes population.

Design

This qualitative study was approved by the Colorado Multiple Institutional Review Board at the University of Colorado Anschutz Medical Campus.

Participants who completed the GEM intervention arm of a pilot clinical trial involving 4 months of following the self-directed GEM guide adapted for prediabetes with use of a Fitbit activity device and Freestyle Libre 2 CGM were invited to be interviewed (N = 22).

Setting

Participants were invited to participate in a brief (15-30 minutes) one-on-one interview via HIPAA compliant Zoom led either by author AC or JP, a medical student research assistant and project manager on the study team, respectively, neither of whom had any prior study interaction with the participants.

Participants

Inclusion criteria for this study were participation in the larger clinical trial. Inclusion and exclusion criteria for the larger study were: age 25-70 years, diagnosis of prediabetes, A1C 6.0-6.4 (this exclusion criteria was due to a study demonstrating that people with an A1c between 5.7 and 5.9 were more likely to revert to a non-diabetes status,³¹ access to a smart phone in order to access the CGM app, ability to read English (GEM guide currently only available in English) and written approval from a primary care provider. Exclusion criteria included: diagnosis of diabetes mellitus, currently taking any diabetes medication, currently taking chronic medication that would interfere with metabolic control (such as prednisone) since this could impact the primary outcome of the clinical trial (A1c), a condition that precludes a low carbohydrate diet (such as gastroparesis) since the GEM intervention involves lowering dietary carbohydrates, a physical or medical condition that precludes walking 120 steps per minute, for 10 minutes or longer since the GEM intervention involves increasing physical activity, advanced kidney disease, active or planned cancer treatment, cannot read English (GEM guide currently only available in English), extreme visual or hearing impairment that would impair real-time CGM use, pregnant or anticipates becoming pregnant in the next 4 months or the treating physician considered the participant inappropriate for the study, such as uncontrolled bipolar disease.

All participants from the larger study were invited by email to participate in the voluntary interview following completion of the trial. They provided verbal consent prior to the interview and were informed that they could skip questions and/or stop participating at any time. Interviews were completed within 16-133 days since the last study visit, and an average of 62 days. Those with a longer duration between the last study visit and interviews occurred due to the addition of interviews being added to bring additional context to the quantitative findings. Participants who did not respond to the initial email were sent a second email one week later and if no response, a third email 2 weeks after that. A reminder email was also sent the day before the interview.

Intervention

As part of the larger study, participants randomized to the GEM intervention received instruction from study staff on use of the Freestyle Libre 2 CGM, Fitbit activity monitor, adapted GEM guide, and were asked to set up text message content (motivational messages such as “Low carbs, low blood glucose” and “Food choices are life choices”), timing and frequency for the 4-month period of the intervention, which were automatically sent for encouragement.

Participants were instructed on use of the CGM, including placement, and recommended scanning frequency (minimum every 8 hours, suggested 20-40 times/day). For the Fitbit Inspire 2 activity monitor, the participant was instructed on its use including use of the Fitbit phone app, indications for removal (showering) and charging. Participants were initially asked to read Unit 1 and encouraged to complete four daily diary logs within 1 week, after which a staff member called the participant to assess comprehension and questions. The participant was then instructed to read and complete units 2-4 of the GEM guide by the 6-week mark, which included 14 days of diaries in Units 2 and 3. Phone calls were scheduled with study staff at the end of weeks 2 and 6. Participants received the automated text messages the remainder of the 4-month period, but no other contact from study staff.

Method

Interviews took place between October 2023 and March 2025, and verbal consent was obtained prior to initiating the interview. The semi-structured interview guide was created by authors TO and JP, and featured questions relating to perceptions and experiences of the GEM program, study devices, GEM guide units, diaries, text messages and program website with an opportunity for additional comments (Figure 1). Compensation was not provided.

Figure 1.

Semi-structured interview Guide

Analysis

The inductive thematic analysis approach was implemented for this study to identify themes and generate codes from interview transcript data.^3,4 Interviews were recorded and automatically transcribed via Zoom and then transcripts were reviewed for accuracy by authors AC and JP. Data saturation was determined to be reached when no new information/themes were presented in interviews, and no new codes could be generated.³²

Analysis of interview transcripts was then completed by authors AC and JP using Microsoft Word. The authors met to form 100% agreement on final codes after initially reviewing the transcripts independently. The final codebook with definitions was created jointly, reviewed and approved by authors AC, JP, EW and TO and then used to independently review the transcripts line-by-line. Each transcript was reviewed through virtual meetings with AC and JP until 100% agreement was reached on final codes for each transcript. Preliminary themes were developed and then reviewed by all authors using a consensus approach until 100% agreement was achieved for final themes and selected representative quotes. Throughout analysis, the authors undertook efforts to ensure quality and scientific rigor by obtaining complete consensus on definitions, codes, and themes.

Results

Sixteen interviews were completed (62% of eligible participants). Three people contacted were not interested in participating and three did not respond to contact. Saturation of data was confirmed via consistent patterns in data by authors AC and JP prior to analysis. Demographic information is summarized in Table 2. The majority of interviewees were White/non-Hispanic (88%) and female (88%). Average age was 63 years.

Table 2.

Participant Demographic Information

Characteristics	(n = 16)
Age – year
Mean ± SD	63.1 ± 7.5
Range	48-71
Sex – n (%)
Male	2 (12)
Female	14 (88)
Race/Ethnicity – n (%)
White, non-Hispanic	14 (88)
Hispanic	1 (6)
Black	1 (6)

Abbreviations: SD: standard deviation.

Interviews yielded five major themes described below. For each code, the number of participants, number of references, and percentage of references per theme are presented. To note, one participant could have more than one reference per code and some of the data were double-coded, if necessary. Therefore, categories are not mutually exclusive and may not add up to 100% for each theme. Code counts are also included in Table 3 and representative quotes included in Table 4.

Table 3.

Code Dictionary and Counts From Participant Interviews (n = 16)

Code	Definition of code	# of participants	# of references^a
Theme 1: Increased insight, tangible health outcome changes, and lifestyle challenges			161
NUTRITION AND GLUCOSE	Comments expressing increased insight into the effect of food choices on glucose readings	14	46
EXERCISE AND GLUCOSE	Comments expressing increased insight into the effect of exercise on glucose readings	13	23
NUTRITION DIFFICULTY	Comments from participants noting difficulties in implementing nutritional lifestyle changes	12	31
WEIGHT	Comments noting decrease in weight during participation	9	18
EXERCISE DIFFICULTY	Comments from participants noting difficulties in implementing exercise lifestyle changes	8	12
GENERAL LIFESTYLE CHANGES	Comments reflecting general observations and insights regarding lifestyle changes	6	9
EXERCISE EASE	Comments indicating ease of implementing exercise lifestyle adjustments	6	10
NUTRITION EASE	Comments indicating ease of implementing nutritional lifestyle adjustments	5	6
A1C	Comments noting observed decrease in A1C during participation	5	6
Theme 2: Positive and negative feedback on the adapted GEM guide and recommendations for improvement			139
Perceptions about GEM g uide as a whole			59
GUIDE FUNCTIONALITY	Positive and negative observations from participants about the GEM guide related to general functionality and form	11	23
DIGITAL VERSION	Comments from participants expressing desire or interest in a digital version of the GEM guide	9	19
SMALL GUIDEBOOK SIZE	Comments from participants expressing interest in a larger guidebook size	6	7
GEM FOLLOW	Comments praising the GEM guide’s easiness of understanding or logical layout	5	5
SMALL FONT SIZE	Comments from participants expressing interest in a larger font size	5	5
Perceptions about i ndividual u nits			80
UNIT 1 POSITIVE	Participants commenting positively on Unit 1, including educational value, format and features	14	28
UNIT 4 POSITIVE	Participants commenting positively on Unit 4, including educational value, format and features	13	17
UNIT 2 POSITIVE	Participants commenting positively on Unit 2, including educational value, format and features	12	20
UNIT 3 POSITIVE	Participants commenting positively on Unit 3, including educational value, format and features	11	15
Theme 3: Positive and negative feedback on diaries, text messages and website utility			139
Perceptions regarding diaries			63
DIARIES IMPRACTICAL	Comments from participants noting that the provided diaries were not practical to use or that they used an alternative method	14	30
DIARIES USEFUL	Comments from participants expressing the positive utility of the diaries as a part of their experience in the study	8	11
DIARIES NOT USED	Comments from participants noting that they did not use the provided diaries during the study	7	10
DIARIES USED	Comments from participants noting that they did record their experiences in the provided diaries to some extent	6	6
DIARIES: OTHER	Other comments related to the diaries, such as inconsistent use over the study period by participants	5	6
Perceptions regarding text message reminders			46
TEXT: OTHER	Other comments by about text messages, such as participants expressing confusion about the source, frequency or purpose of the text messages	9	15
TEXTS UTILITY POSITIVE	Comments from participants expressing that the texts were useful or helpful to them	8	11
TEXTS CONTENT POSITIVE	Comments noting enjoyment or approval of the content of the text messages	7	8
TEXTS FREQUENCY UNCHANGED	Comments that participants kept the frequency of texts unchanged from the default	7	7
TEXT CONTENT NEGATIVE	Comments expressing criticism of the content of text messages	3	5
Perceptions regarding website			30
WEBSITE NOT USEFUL	Comments describing limited utility or engagement with the website after visiting it	7	10
WEBSITE NOT VISITED	Comments stating that the participant did not visit the website	7	7
WEBSITE VISITED	Comments stating that the participant visited the website	6	7
WEBSITE USEFUL	Comments from participants expressing that they found the content of the website useful	5	6
Theme 4: CGM benefits and challenges to user experience			45
CGM POSITIVE	Comments noting positive experiences with the CGM device, such as the convenience or fascination by real-time data availability	11	22
CGM SENSOR ISSUES	Comments noting issues with the CGM sensor, such as falling off or discomfort	6	15
CGM: OTHER	Other comments related to CGM use, such as wanting interpretation and more personalized progress	6	8
Theme 5: Program enjoyment, study support and overall reflections			111
GEM POSITIVE	Comments expressing positive comments about the GEM program as a whole	14	41
ENJOYED PARTICIPATING	Comments expressing how the participant enjoyed the experience participating in the study as a whole	12	18
SUPPORTED	Participants commenting positively on the level of assistance and education received by the study team	10	20
GENERAL REFELECTIONS	Insightful comments from participants that reflect a general take-away from participation in the study	8	19
RECOMMEND	Comments expressing that participants have or would recommend participation in the GEM program to others	6	7
GEM NEGATIVE	Participants expressing challenges with the program as a whole, such as dietary restrictions, stress or unpredictability of data	5	6

^a# of references = the number of times this code was referenced; ie, one participant could have more than one quote per code. Some of the data were double-coded, if necessary.

Table 4.

Themes and Representative Quotes From Participant Interviews (n = 16)

Themes	Representative quotes
Theme 1: Increased insight, tangible health outcome changes, and lifestyle challenges	I liked the real time information that I got from the CGM. And being able to see in real time the data of how food that I was ingesting was impacting my blood glucose levels, and also how walking after eating a meal or eating really any food help to mitigate the spikes in blood glucose. - Participant #1
	Making me more aware of how many carbs I ingested in a day, and what it was doing to my blood glucose. Raising the blood glucose to pre-diabetic levels. And it made me really become more conscious of what I ate. - Participant #3
	I hadn’t realized the effect that exercise has on blood sugar. I hadn’t been thinking about it in those terms. So understanding when to exercise and trying to learn what type of exercise helps reduce my blood sugar, and when, was very, very useful. - Participant #4
	And the other thing I’m trying to really get better at is more activity. The hardest time for me is in the evening. It’s like once I cook dinner, and you know, done with dinner, I really don’t wanna go down and sit on the stationary bike for 30 minutes. I really don’t wanna do that. - Participant #5
	I lost significant weight. - Participant #7
	I could evaluate the impact of food. And so that was very positive. - Participant #8
	The other thing I probably learned in this one is not just for food itself. It’s the quantity of the food that makes a huge difference. - Participant #9
	I learned how fast [blood glucose] goes down the minute I exercise after I eat. - Participant #10
	I think the biggest takeaway I had was the impact that movement has on everything. I was already doing the lifestyle eating part. It allowed me to include things that I might not normally have just because of the way I was able to incorporate cardio and that kind of thing to balance everything out. - Participant #12
	I tend to do quite a bit of walking, but it was nice to get a feel for what time periods to have that exercise after eating would be the most beneficial, so that I found that really helpful. - Participant #15
	I felt like I did learn a lot in terms of just the specifics of the food choices I make, and how that impacts glucose. So that was very helpful. - Participant #16
Theme 2: Positive and negative feedback on the adapted GEM guide and recommendations for improvement	It was clear, it was easy to follow. - Participant #1
	[Unit 2] did a good job of explaining the connection between increased physical activity and reduction in spikes, in blood glucose. - Participant #1
	I thought [Unit 1] was pretty specific. [The author] had a lot of information. And you know [the author] stressed also that requires diligence and work, and you have to change your attitude. I thought it was well written. - Participant #3
	[Unit 4] was a good summary. It was a good just pulling everything together. - Participant #4
	The food choices, again, were a big help [in Unit 3]. - Participant #5
	The GEM guide was very useful, and a person’s got to want to do it themselves. It’s kind of like a ‘you get out of it what you put into it’ mentality. - Participant #6
	I think our blood sugar is amazing how many things affect it. That’s what I loved. And I loved the pathway with that book. -Participant #7
	If the type was bigger, if it was in a little bigger format, that would be great. - Participant #8
	I would have loved something where I could just make my notes on the computer and even some links to an Excel sheet where I could really track my daily progress. - Participant #9
	I did find the font to be a little on the small side and sometimes where the binding was, it would be where the words were. - Participant #11
	The visuals were helpful and good. And I liked how main things were bolded so the layout is good. - Participant #12
	It was really good information and the way it was progressive and reading it and then introducing the next thing that was very helpful as well. It just built upon itself. - Participant #12
	The book size is good, it’s legible, it fits. You can take it places. So I thought that part was really handy. - Participant #15
Theme 3: Positive and negative feedback on diaries, text messages and website utility	[The diaries] were useful. - Participant #1
	Sometimes [the text messages] were very exciting, because there’d be like a part one and a part two. And I was very curious to see what part two was. - Participant #2
	[The website] was for sure helpful. - Participant #2
	[The diaries] weren’t enough for the whole program. - Participant #3
	It was good. I really learned a lot from this keeping the diary. - Participant #3
	I personally like to do everything electronically. I’m not very good at paper and writing things down. If I had it in my diary on my calendar on my computer, and I had an easy way to fill in at certain intervals with reminders, then I would have. I would have done a little bit better on that, because my calendar runs my life. -Participant #4
	I kind of started and then I got behind and didn’t finish [the diaries]. - Participant #4
	I didn’t really enjoy the text messages from the study. I thought that they were trying to be too short and cutesy. It would have been more powerful if it was even a couple of sentences message that was something more substantial. - Participant #4
	My nurse and I would talk, she would ask if [the text messages] were too frequent, I said no. So, I think they were sent to me at the right interval, and were helpful little hints of what I should be doing, and most of the time came at the right time. - Participant #6
	Well [the diaries] were [useful], and I went to the other extreme to write down each carbohydrate and the fiber, and added it at the end. So that was helpful. - Participant #7
	I did go to some of the [website] resources. And I found that some of them to be helpful, and some of them just to be kind of generic. - Participant #11
	I mean on the using your discovery diary I didn’t really do that. I used the Fitbit and I have different apps that track things like the iPhone health app. - Participant #12
	[I did not find the website useful] probably because I already have a lot of healthy recipes and I got a lot of healthy meals on rotation so and there’s so many recipes on my iPhone that I have access to. - Participant #12
	[The text messages are] encouraging. - Participant #13
	[I was using the included diaries] only a little. In the beginning I was busy filling in my MyFitnessPal and doing it that way. - Participant #14
	When I was charting things in my book, I would tend to also put that information into my phone. So I felt like I was double entering a lot of information. And it caused me to slack off on entering into my book. - Participant #15
Theme 4: CGM benefits and challenges to user experience	I’m gonna ask my doctor if I can get a prescription for a CGM. Not to use all the time, but to use now and then to sort of just dial things back in or check on things. - Participant #2
	I would say that was really the most problematic, that I had to like call them 2 or 3 times. One day one monitor lasted 10 days. Another one lasted 3 days and it just fell off. - Participant #3
	It was very interesting to be able to monitor and actually see in real time how something even as simple as a sandwich affects your blood sugar levels. So having that real time feedback was very helpful. - Participant #4
	The service on that was great. I was responded to very quickly, and the new devices were sent out very quickly. - Participant #4
	Just knowing what your blood sugar is throughout the different times of the day is invaluable. - Participant #5
	The only thing would be changing the device, maybe, but that’s a part of using it. -Participant #6
	I also had some failed sensors and the company helped me replace those. - Participant #8
	I didn’t make the right food choices when I was doing it on my own. So when I got the continuous glucose monitor in October it was very helpful in guiding me in making better food choices. - Participant #9
	I think that the CGM Really brings it home to you that oh I think I’m doing okay, because a lot of people think they’re eating right. And they’re not. - Participant #14
Theme 5: Participant program enjoyment, study support and overall reflections	I’m grateful for the program. I learned a lot. I had great results. - Participant #3
	It was extremely helpful. I really learned a lot. I really didn’t have the knowledge before about diabetes and the different elements that make an impact on that. So I found it extremely educational. - Participant #4
	The team was absolutely amazing. [Study staff] were so helpful, and really took time to explain anything that I needed and were very responsive when I had questions. - Participant #4
	I’ve recommended it to a couple of my friends. I really do think that it would be beneficial for most people. - Participant #5
	It was a wonderful educational tool and I needed that. I needed a wake-up call. It provided me with immediate feedback that allowed me to make real drastic changes. - Participant #9
	Nothing really is a magic pill. The only magic pill is continuity and making choices the right choices 24 hours a day. - Participant #9
	I thought it was easy to contact people via email if I had a question. My appointments were really informative. I thought that was really well done. I appreciated that all the information went to my doctor. I thought you guys did a good job. - Participant #10
	I really feel blessed that I got to trial this and try something different. I knew I needed to make changes and this was a good next step. - Participant #11
	I’m thankful for it. I’m really appreciative. I learned a lot and I’m really glad I got to participate. - Participant #12
	The guide does say everybody’s different. And I think that’s important to stress because I could eat half a bagel and my husband could eat half a bagel, and we’d get totally different results. - Participant #14
	I think that for most people it’s awesome. They’re great guidelines, and it does open your eyes to what you can eat and what you can’t, and how and what changes you can make that aren’t really difficult to incorporate. - Participant #14
	I think it’s a great idea to use the program again in the future. - Participant #15

Theme 1: Increased Insight, Tangible Health Outcome Changes, and Lifestyle Challenges

Overall, participants positively expressed the insight that the GEM guide and CGM provided into the effects of daily life choices such as food and physical activity on blood glucose and A1C, often leading to improvement in A1C and weight, though changing some exercise and dietary habits were perceived as challenging.

Specifically, most participants (n = 14 participants, 46 references (28.6%)) noted increased insight into the relationship between their nutrition and glucose readings on their CGM, and most (n = 13 participants, 23 references (14.3%)) also noted increased insight into the relationship between physical activity and glucose readings, as one participant noted:

“Just knowing what types of things raise my blood sugar is really good to know.” - Participant #5

Many participants also noted that they lost weight (n = 9 participants, 18 references (11.2%)) or noticed a drop in their hemoglobin A1C level (n = 5 participants, 6 references (3.7%)) as a result of participation in this study:

“I lost 30 pounds and my A1C came down towards a better reading.” - Participant #3

However, many participants noted difficulties implementing lifestyle changes in their nutritional habits (n = 12 participants, 31 references (19.3%)), with reasons including complexity of changing dietary habits and decreased satiety, as stated by one participant:

“I was struggling with being hungry all the time.” - Participant #1

Many also struggled to implement changes in physical activity habits (n = 8 participants, 12 references (7.5%)), with participants often citing time constraints. Other participants had less difficulty implementing changes to their nutritional (n = 5 participants, 6 references (3.7%)) or physical activity (n = 6 participants, 10 references (6.2%)) habits by being able to make smaller changes. One participant noted that this intervention was the only one that was successful so far for them for changing lifestyle habits. Two participants noted that the success of this program is rooted in the increased level of insight provided.

Theme 2: Positive and Negative Feedback on the Adapted GEM Guide and Recommendations for Improvement

Participants generally viewed the adapted GEM guide and each of the four units as useful and educational, but expressed desire for a digital version. Additionally, there were some criticisms about the program as a whole and about the limited practicality of the small book and font size.

Specifically, most participants (n = 11 participants, 23 references (16.6%)) provided positive feedback about the GEM guide’s functionality and form. Some of these same participants, however, had some criticisms of the guidebook form and functionality at other points of the interviews such as need for a larger guidebook size (n = 6 participants, 7 references (5.0%)) or larger font size (n = 5 participants, 5 references (3.6%)), as stated by one participant:

“The only thing I’d change is make the book a little bit larger. I appreciate the small size, but I think if you made a junior size notebook, I think it’d be better and more useful.” - Participant #6

Several participants (n = 9 participants, 19 references (13.7%)) also expressed interest in a digital version of the GEM guide. Even with these criticisms, some participants (n = 5 participants, 5 references (3.6%)) indicated that the guidebook was easy to follow.

All four of the units in the GEM guide were positively received, noting their educational value, format and features. For Unit 1, participants (n = 14 participants, 28 references (20.1%)) remarked mostly about its educational value and foundational knowledge it provides about prediabetes and diabetes, as one participant remarked:

“I think for me unit one gave me a foundational knowledge to be able to build for the rest of the program.” - Participant #4

Unit 2 similarly received positive commentary from a majority of participants (n = 12 participants, 20 references (14.4%)), with many remarking on the increased insight they obtained from using the guide on the relationship between physical activity and glucose. Unit 3 also was received positively by a majority of participants (n = 11 participants, 15 references (10.8%)), with many praising information about different food choices and the impact making these choices can have on glucose, as one participant noted:

“I liked that [Unit 3] gave you options and examples of [food options] that were good and then how to incorporate all of that in a healthy way.” - Participant #12

The last unit, Unit 4, was similarly commented positively upon (n = 13 participants, 17 references (12.2%)) for its ability to summarize the guidebook and provide encouragement and motivation for the future.

Theme 3: Positive and Negative Feedback on Diaries, Text Messages and Website Utility

Overall, study features like diaries, text messages and the website had mixed feedback. Diaries were used by some participants but were generally considered impractical, text messages had mixed feedback on utility and style, and the website had some but limited engagement by the participants.

Specifically, some participants explicitly stated that they used (n = 6 participants, 6 references (4.3%)) or did not use (n = 7 participants, 10 references (7.2%)) the diaries, but the vast majority (n = 14 participants, 30 references (21.6%)) of participants noted that the diaries were not practical to use or that they preferred to use an alternative method to record their data or experiences, such as this participant:

“I used my own little [diary] just because it was a little bit bigger and I could write down [more].” - Participant #5

Some participants (n = 5 participants, 6 references (4.3%)) also remarked on reasons for being inconsistent with the diaries or not completing them, such as losing interest or falling behind.

Many participants (n = 8 participants, 11 references (7.9%)) found the text message reminders and encouragement useful and participants (n = 7 participants, 8 references (5.8%)) noted enjoyment or approval about the content of these text messages, as this participant did:

“[The text messages] were just good little reminders for the day.” - Participant #2

Although they had the opportunity to change the frequency of the text messages, many participants (n = 7 participants, 7 references (5.0%)) left the default frequency unchanged. However, other participants (n = 9 participants, 15 references (10.8%)) expressed confusion about the source, frequency or purpose of the text messages. Some participants (n = 3 participants, 5 references (3.6%)) also criticized the content and/or style of the text messages.

For the website resource, many participants (n = 7 participants, 10 references (7.2%)) indicated that it was not useful for them after visiting it, often stating that they were hoping for more depth, preferred other resources, or were not interested. Some participants (n = 5 participants, 6 references (4.3%)), indicated that the content of the website was useful for them, as noted by this participant:

“I looked a lot at the [website] FAQ’s and the recipes.” - Participant #2

Theme 4: CGM Benefits and Challenges to User Experience

Participants had numerous comments related to the CGM device provided to them in the study. While the majority of comments noted a positive user experience, and desire to learn more about their CGM data, others brought attention to difficulty adjusting to the device components, like the sensors.

The majority of interviewees (n = 11 participants, 22 references (48.9%)) had a positive experience wearing and using the CGM device. In particular, participants enjoyed being able to see their CGM data and how nutrition and physical activity affected their glucose levels in real time, as noted by this participant:

“The real time continuous data was a real help for me to see how certain food groups and exercise, or brisk walking at least, was able to help with spikes in blood glucose levels.” - Participant #1

However, some participants (n = 6 participants, 8 references (17.8%)) wished that they could have had access to additional feedback, such as interpretation of their CGM data:

“I wish I would have gotten more feedback about the interpretation of how I did with the data that was turned in.” - Participant #13

Others (n = 6 participants, 15 references (33.3%)) noted issues with the sensor such as frequent detachment or needing replacements due to technological errors, as was the case with this participant:

“The only thing I struggled with at all was the sensor wouldn’t always stay on my skin.” - Participant #12

Those needing new sensors did note that the study team was able to get them replaced in an easy and timely manner.

Theme 5: Program Enjoyment, Study Support and Overall Reflections

Participants emphasized their overall appreciation for the study. They noted that they enjoyed participating in the study, felt well supported by the study team, and would recommend the GEM program to friends and family.

The majority of interviewees (n = 14 participants, 41 references (36.9%)) reflected on the positive aspects of the program, including how helpful the information was and the impact it had on their knowledge of prediabetes and diabetes. Most participants (n = 12 participants, 18 references (16.2%)) commented on their appreciation of being able to participate in the program. However, some participants (n = 5 participants, 6 references (5.4%)) mentioned some challenges of participating, such as being vegetarian, or feeling stressed about the data, as one participant stated:

“I found it really frustrating when I was trying to predict my numbers, and I got really discouraged with that.” - Participant #15

Interviewees (n = 10 participants, 20 references (18.0%)) also appreciated the level of assistance and education from the study team, and felt encouraged to continue participating:

“Just having people to talk to was very beneficial for me. That one-on-one coaching was essential for my success.” - Participant #9

Participants (n = 8 participants, 19 references (17.1%)) also reflected on general impressions of the program, and their participation and results, such as difficulty keeping glucose “in range” and understanding that everyone responds differently to lifestyle changes. Lastly, some participants (n = 6 participants, 7 references (6.3%)) said that they would recommend the program to others, one of which said that they would participate again:

“I would participate in the trial again, because I learned a lot, and I feel like I'm empowered to take more control of my health. I feel like that investment in my health was something that was very, very beneficial, and I would recommend it to somebody else.” - Participant #4

Conclusion

This study sought to explore participant experiences with the GEM program from a subset of participants with prediabetes who completed a pilot clinical trial. Interviews revealed five major themes related to: (1) increased insight into how nutrition and physical activity affect blood glucose levels and tangible outcomes on A1C and weight (2) positive and negative feedback on the adapted GEM guide, including functionality and content with recommendations for improvement, (3) positive and negative feedback on other GEM components, including diaries, text messages, and website, (4) benefits and challenges to user experience with CGM, and (5) overall enjoyment, support and reflections from participation in the program.

Several themes reflect patterns observed in prior literature. In a previous application of GEM in participants with T2D, it was found that there was a significant decrease in A1C levels and BMI from pretreatment to 3 months following the GEM program.²⁵ Similarly, many participants in this study reported decreases in weight and A1C, suggesting that this pilot clinical trial may result in a similar trend. However, this is speculative as these are self-reported themes and not objective data. This aforementioned study also noted increases, on average, in diabetes knowledge and diabetes empowerment, though these differences were not significant. Themes in this study such as high regard for the educational value of the GEM guide, increased insight into the relationship between glucose and lifestyle factors, and enjoyment of the CGM suggest that participants may have similar increases in modified diabetes knowledge and empowerment (through increased insight into their own glucose physiology).

Another theme from participant interviews is that most participants enjoyed using the CGM due to the convenience and the level of insight it provides. This theme mirrors a systematic review of qualitative studies that found that CGM can improve convenience and self-management (feeling of ownership and increased awareness of glycemic control),³³ though this analysis also identified themes of participants being burdened with device complexities and exclusion by barriers to access. The latter two themes were not frequently mentioned by participants in this qualitative study. Unlike this systematic review, some participants mentioned sensor issues (such as frequent detachment), and in future studies more information on how to improve adhesion such as providing the PANTHER tools should be considered.³⁴

A majority of participants also mentioned difficulty in implementing nutritional and exercise-related lifestyle adjustments, with common reasons being complexity in changing their diet and less satiety, and time constraints for implementing sufficient physical activity. In a systematic review of barriers and facilitators to diet and physical activity behavioral interventions, it was found that reasons that most adults globally do not meet dietary or activity guidelines range from a variety of individual, community, and intervention design factors.³⁵ Some of these include unchangeable community factors (like weather impeding exercise) and time/resource constraints which were frequently mentioned by participants during interviews, but this analysis does not mention difficulty in substituting foods which many participants brought up in the interviews.

Themes found in the interviews indicated that the GEM program is effective in empowering participants with prediabetes by increasing insight and knowledge about the relationship between lifestyle choices and glucose excursions. Similar to study findings in participants with type 2 diabetes, the GEM lifestyle guide combined with CGM monitoring can be a tool to increase insight and motivate change in objective values such as A1C and weight in those with prediabetes.

This thematic analysis also revealed which study features are most helpful and what could be changed in future similar studies. For example, many participants spoke positively about having responsive study support and encouragement but expressed interest in a digital version of the GEM guide and diaries. Future work that expands on this study could include sharing an e-version of the GEM guide, creation of an app, or the utilization of an online platform with a shareable spreadsheet template featuring a digital version of the GEM guide with fields for the diaries or other notes. Additionally, many participants mentioned difficulty making nutritional lifestyle adjustments. Although the GEM intervention featured a website with FAQ’s, food options and recipe ideas, additional resources could be provided, such as social media accounts that feature certified dietitians who specialize in blood sugar-friendly meals. This feedback is a reminder of the importance of qualitative research – it allows a perspective that wouldn’t be observed through objective data alone and helps better understand how to improve future similar work and enhance the experience for the participants.

A strength of this study was providing a patient population with CGM technology to use in partnership with a lifestyle guide who may not have been able to access it due to insurance or other barriers. The positive feedback and insight shared by participants could support more widespread application of technology such as CGM to people with prediabetes. This was also the first qualitative study to solicit feedback about the GEM program from patients with prediabetes.

Our study was limited due to having a small sample size and homogeneity of participants (predominantly White, non-Hispanic and female individuals from Denver Metro/Central Colorado), which limits generalizability. As always with qualitative research, social-desirability bias, selection bias and recall bias were factors in this study.

With the intention of expanding this pilot clinical trial to a larger, more diverse sample of participants, the results of this qualitative study will enable future research to modify or improve aspects of the study design and the GEM program that can be more effective for individuals with prediabetes.

This study provided valuable feedback for further adaption of the GEM intervention for a prediabetes population. Feasibility of converting the GEM guide to an app or other digital platform will be explored in future studies. Other valuable feedback related to the website and text messages will be incorporated. Use of CGM by this prediabetes sample was felt to be beneficial by the majority of participants and will be incorporated into future studies.

So What?

What is Already Known on This Topic?

Prediabetes is a serious health problem that is prevalent in millions of people worldwide. Millions of people with prediabetes transition to type 2 diabetes (T2D) annually. Glycemic Excursion Minimization/Glucose Everyday Matters (GEM) has been shown to improve outcomes in individuals with type 2 diabetes compared to routine care alone, but has not been studied in individuals with prediabetes.

What Does This Article Add?

This is the first study to use an evidence-based alternative lifestyle intervention focused on reducing postnutrient glucose excursions in patients with prediabetes delivered through primary care practices.

What are the Implications for Health Promotion Practice or Research?

GEM combined with continuous glucose monitoring (CGM) may improve glycemic outcomes in patients with prediabetes and has the potential to be a preventive strategy against type 2 diabetes. Preventing or delaying this may significantly reduce healthcare costs and reduce mortality and morbidity for many individuals. Larger studies are needed.

Footnotes

Acknowledgements

We would like to express our sincere gratitude to Daniel J. Cox, PhD for developing and permitting us to use the GEM lifestyle guide that we adapted for a prediabetes population. We also extend our appreciation to our colleagues and advisors for their support and feedback throughout the research process. Finally, we acknowledge the participants of this study for their time and willingness to contribute to this work.

ORCID iDs

Jessica A. Parascando

Sean M. Oser

Tamara K. Oser

ClinicalTrial.gov Identifier

NCT05580978 .

Ethical Considerations

This study was approved and determined to be minimal risk by the Colorado Multiple Institutional Review Board (21-4931). Informed consent to participate in the larger clinical trial was written, and participation in the interview portion was oral.

Author Contributions

A.C. conducted and transcribed interviews, analyzed the interviews, contributed to writing of all sections of the manuscript, creation of tables and reviewed/edited the manuscript. J.P. conducted and transcribed a majority of interviews, analyzed the interviews, contributed to writing of the results and discussion, creation of tables, and reviewed/edited the manuscript. E.W. contributed creation of tables and reviewed/edited the manuscript. B.P. contributed to creation of tables and reviewed/edited the manuscript. S.O. contributed to review/editing of the transcript. T.O. conceptualized the pilot clinical trial from which these participants were recruited, contributed to the writing of the discussion section and contributed to reviewing/editing of manuscript.

Funding

The authors received no financial support or compensation for this specific subproject, authorship, or publication of this article. The larger clinical trial was funded by Abbott Diabetes Care.

Declaration of Conflicting Interests

The authors declared potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Antonio Calderon, BA does not have any conflicts of interest. Jessica A. Parascando, MPH does not have any conflicts of interest. Elizabeth Westfeldt, BSN, RN does not have any conflicts of interest. Britney Prince, BS does not have any conflicts of interest. Dr. Sean M. Oser, MD, MPH, CDCES reported serving on advisory boards for Dexcom, Ascensia, and Blue Circle Health, with related fees paid to his employer, the University of Colorado, not to him. Dr. Tamara K. Oser, MD reported serving on advisory boards for Dexcom and Blue Circle Health, with related fees paid to her employer, the University of Colorado, not to her.

Data Availability Statement

Data is available upon request.*

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