Effects of Sleep, Physical Activity, and Shift Work on Daily Mood: a Prospective Mobile Monitoring Study of Medical Interns

Abstract

Background: Although short sleep, shift work, and physical inactivity are endemic to residency, a lack of objective, real-time information has limited our understanding of how these problems impact physician mental health. Objective: To understand how the residency experience affects sleep, physical activity, and mood, and to understand the directional relationships among these variables. Design: A prospective longitudinal study. Subjects: Thirty-three first-year residents (interns) provided data from 2 months pre-internship through the first 6 months of internship. Main Measures: Objective real-time assessment of daily sleep and physical activity was assessed through accelerometry-based wearable devices. Mood scaled from 1 to 10 was recorded daily using SMS technology. Average compliance rates prior to internship for mood, sleep, and physical activity were 77.4, 80.2, and 93.7%, and were 78.8, 53.0, and 79.9% during internship. Key Results: After beginning residency, interns lost an average of 2 h and 48 min of sleep per week (t = − 3.04, p