Prevention
Conditions
Brief summary
The GLOW UP study is a single-center, prospective, observational case-control study conducted in St. Gallen, Switzerland. The primary aim of the study is to examine to what degree lifestyle data collected from wearable devices and a smartphone app can identify individuals with prediabetes (vs. normoglycemic) in a real-world setting. The study also aims to characterize variability in lifestyle and glycemic patterns and to examine how between- and within-person differences relate to diabetes risk; to identify personalized predictors of early metabolic dysregulation. The study also evaluates new image-based meal tracking algorithms for predicting glycemic control and examines how reminder messages influence adherence to a \ 4-week meal logging protocol. The study aims to enroll 200 adults aged 45 years and older with a BMI of at least 25 kg/m² and no known diagnosis of diabetes, including 100 participants with prediabetes and 100 normoglycemic (metabolically healthy) controls. Participants will be classified at the baseline visit using HbA1c and fasting plasma glucose (FPG) tests, with prediabetes defined as HbA1c 5.7-6.4% and/or FPG 5.6-6.9 mmol/L, and normoglycemia defined as HbA1c \<5.7% and FPG \<5.6 mmol/L, following clinical standards. During the \ 4-week observational period, participants will be asked to wear a smart ring, a wrist-worn smartwatch, and a blinded continuous glucose monitor (CGM). Participants will be asked to log/take-images of their meals via a study app and to complete brief questionnaires (e.g., tracking mood, stress, and contextual meal annotations) via ecological momentary assessments. FPG and HbA1c samples will be collected at baseline to classify participants as prediabetic or normoglycemic, and again at follow-up (\ 4 weeks), which will serve as the primary outcome to evaluate associations between lifestyle and wearable-derived data and diabetes risk status.
Interventions
None listed
Sponsors
University of St.Gallen
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
45 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Citizens or residents of Switzerland who are German-speaking (main place of living or employment in Switzerland). * Age ≥45 years. * BMI ≥25 kg/m² (overweight or obese). * Regular access to a smartphone (iOS or Android) with a data plan. * Able to use smartphone applications. * Able to walk independently.
Exclusion criteria
* History of stroke, heart disease, renal failure, cancer, or diabetes (type 1 or type 2). * Past vascular bypass surgery or angioplasty. * Current or planned use of glucose-lowering medications during the upcoming 4 weeks (e.g., GLP-1 receptor agonists, metformin). * Pregnant or breastfeeding. * Relevant skin conditions at wearable placement sites (e.g., upper arm). * BMI \<25 kg/m² confirmed at enrollment. * FPG ≥7.0 mmol/L and/or HbA1c ≥6.5% (newly identified type 2 diabetes); Individuals who meet type-2 diabetes criteria at enrollment, based on Swiss/ADA diagnostic criteria will be informed of blood test results and referred to a GP. These individuals will be deemed ineligible and excluded from the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Diabetes risk status (prediabetic vs. normoglycemic) | At follow-up, week 4 | Prediabetic (FPG levels 5.6-6.9mmol/L and/or HbA1c levels 5.7%-6.4%) Normoglycemic (FPG levels \<5.6mmol/L and HbA1c levels \<5.7%) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Diabetes risk at alternative FPG and HbA1c thresholds | At follow-up, week 4 | Participants will also be classified using alternative FPG and HbA1c thresholds based on the observed distribution of glycemic values in the resulting study sample (e.g., high-risk prediabetes FPG ≥6.0 mmol/L, HbA1c ≥6.0%). Additionally, continuous FPG and HbA1c values will be analyzed. |
| Metabolic phenotypes | At follow-up, week 4 | Metabolic phenotypes defined based on a combination of FPG, HbA1c, body mass index (BMI) and visceral fat levels. |
| Continuous glycemic control | Up to 4 weeks | Continuous glucose levels (mmol/L) over the \~4-week period to characterize dynamic glucose patterns. |
| Lifestyle profiles | Up to 4 weeks | Lifestyle patterns derived based on nutrition (e.g., macro-nutrient composition), physical activity, sleep, stress levels (e.g., survey-based, HR/HRV). |
| Adherence to image-based food tracking | Up to 4 weeks | Number of meal logs completed |
Countries
Switzerland
Contacts
CONTACTMia Jovanova, Dr.
Outcome results
None listed