SAT-820 Continuous Monitoring of Human Daily Rhythms Using Multiple Sensing Devices

Abstract Disclosure: K. Kato: Chubu Electric Power Co., Inc., Oishi kenko Inc., Abbott Japan LLC, Kurabo Industries Ltd. K. Kinouchi: Chubu Electric Power Co., Inc., Oishi kenko Inc., Abbott Japan LLC. K. Kiyono: Kurabo Industries Ltd., JSR Corporation. H. Itoh: Chubu Electric Power Co., Inc., Oishi kenko Inc., Abbott Japan LLC. K. Hayashi: Chubu Electric Power Co., Inc., Oishi kenko Inc., Abbott Japan LLC. The circadian rhythm of living organisms is a near 24-hour cycle of self-sustainable variations under the constant condition. This is primarily driven by the biological clock which operates through the transcriptional-translational feedback loop at the cellular level and governs metabolism, behavior, and endocrine functions. Circadian rhythm disruption is associated with a wide array of pathophysiology such as obesity, cancer, and neurological disorders. While the central clock in the hypothalamus is reset by light, the peripheral clock is entrained by metabolic inputs such as food and exercise. In addition to such environmental cues, psychosocial factors comprising family status, working schedules, commuting hours, among others presumably impinge on temporal patterns of behavior, thereby contributing to circadian misalignment in humans. Whereas the impact of a given zeitgeber (time-giver) on human circadian physiology needs to be evaluated in the laboratory setting, the impact of such modern and urban types of environmental perturbations can only be assessed under real-world and uncontrolled conditions in light of the inherent and complex nature. In recent years, IoT technology allows us to continuously measure biological information (e.g., heart rate and estimated blood sugar levels). In this study, we aimed to examine the potential entrainment factors uniquely in humans which dictate human biological and behavioral rhythms in real-world environments.25 patients undergoing outpatient treatment at the Division of Endocrinology, Metabolism, and Nephrology, Department of Internal Medicine, Keio University School of Medicine were recruited. The home environmental parameters (e.g., temperature, humidity, light intensity, noise, atmospheric pressure, and so on) were collected using environmental sensors, and biometric information (e.g., heart rate, subcutaneous glucose concentrations) was measured using wearable devices and flash glucose monitoring. Daily eating behavior was recorded using a mobile app. The information obtained from these modalities were integrated and visualized to examine their periodicity and characteristics. The average age of the subjects was 62.3, and diabetes, dyslipidemia, hypertension were noted in 80% of the study participant. The average BMI and HbA1c were 25.3 kg/m2 and 6.5%, respectively. Using the Cosinor analysis, daily rhythm was confirmed in the heart rate and glucose levels, as well as environmental parameters such as temperature and humidity. Thus, wearable sensing devices and mobile apps have enabled us to continuously monitor and perform the rhythmic analyses of human metabolism, behavior, physiology, and environment, and may open a new avenue for better understanding of the human circadian pathophysiology underlying individual lifestyle patterns. Presentation: Saturday, July 12, 2025