Jaime Marrero, B.S. ²; Yohana De Jesús-Berríos, MD¹; Annabell C. Segarra, Ph.D. ¹;

Farah Ramirez-Marrero, Ph.D. ²; Lida Orta Anés, Ph.D. ¹; Cruz M. Nazario, Ph.D. ¹;

José Agosto Rivera, Ph.D. ²

1- UPR-Medical Sciences Campus 2- UPR-Rio Piedras Campus

Introduction: Sleep disruption during medical residency is a significant risk factor for medical trainees’ exhaustion and can lead to burnout. This leads to an increased risk of medical errors, development of anxiety and emotional health complications like depression and ideation of self-harm. Individual coaching intervention with physicians in-training revealed that some residents struggle with sleep difficulties during the night-float rotation. We propose that differences in the synchrony of the residents’ circadian oscillators and their work shift may be associated with sleep disturbances.

Methods: This is a longitudinal cohort study of repeated measures in sixteen medical residents. Participants were followed for 3 consecutive rotation blocks covering a diurnal pre-float rotation, the night float rotation and a post-float diurnal rotation. Participants also completed a series of questionnaires through each rotation. Participants wore a dermal sensor to evaluate changes in core body temperature to determine circadian oscillation. A wrist sensor monitored sleep and activity of the participants to assess the degree of synchrony between parameters measured. Saliva samples were collected to measure cortisol and melatonin levels, to analyze stress and explore circadian fluctuations.

Results: Analysis is ongoing. Information was collected from each participant to measure the outcome variation according to hazard exposures and other characteristics. We have taken repeated measurements on the same participants in efforts of increasing statistical power. Due to the small sample size, the importance of study’s results is not based solely on statistical significance, but also on clinical significance. We used specialized software to study the oscillation of measurements, assess the shift in rhythmicity along the night float rotation, and explore possible causal relationships between parameters measured.

Conclusions: Evaluation of temperature data shows a disruption in the oscillation of temperature including shifts in phase and period during the night float. Preliminary sleep analysis shows differences in sleep duration, onset, and timing.

Acknowledgements: We would like to thank the National Institute of General Medical Sciences (NIGMS) of the National Institute of Health for the funding support. (Award Number U54GM133807). The protocol for this project was evaluated and approved by the UPR-RCM IRB (A0260120) and the UPR-RCM Institutional Biosafety Committee (IBC-#109821).