Comparing Human-Smartphone Interactions and Actigraphy Measurements for Circadian Rhythm Stability and Adiposity:...

Area of Science:

• Chronobiology
• Obesity Research
• Digital Health

Background:

• Adiposity and circadian rhythm are linked, but their relationship requires further investigation.
• Comparing actigraphy with smartphone app-based circadian rhythm measurement is crucial for understanding digital health tool potential.

Purpose of the Study:

• To investigate the relationship between adiposity and circadian rhythm.
• To compare circadian rhythm measurements from actigraphy and a novel smartphone app.
• To hypothesize that the app offers more comprehensive data and stronger correlations with adiposity.

Main Methods:

• 78 participants (obesity, overweight, controls) wore actigraphy devices and used the Rhythm app for 4 weeks.
• Data collected included sleep time, chronotype, and circadian rhythm regularity.
• Correlations between adiposity indices and circadian rhythm indicators were analyzed, controlling for physical activity, age, and gender.

Main Results:

• App and actigraphy showed similar sleep onset/wake times, but the app indicated longer wake after sleep onset.
• The obesity group exhibited lower interdaily stability (IS) compared to controls using both methods.
• App-measured IS negatively correlated with BMI; both app and actigraphy IS correlated with body fat percentage and visceral adipose tissue area.

Conclusions:

• Interdaily stability (IS) is significantly correlated with adiposity indicators.
• Smartphone app-based circadian rhythm measurement, tracking human-smartphone interactions, shows promise for obesity research and prevention.