Psychological and lifestyle factors that influence the serial reporting of postconcussion-like symptoms in a non-concussed population

Background: Symptoms related to concussion are generally found to be nonspecific in nature, as they are also reported by non-concussed individuals. What is currently not known is whether the symptoms vary over time, and whether they are also influenced by a multitude of factors. Objective: The aim of this study was to investigate the potential influence of psychological, lifestyle, and situational factors on the change in postconcussion-like symptoms reported over 7 consecutive days in a cohort of normal individuals. Design: This was a longitudinal observational study. Setting: The setting was a real-world context. Participants: A convenience sample of 180 non-concussed university students were enrolled. Of these, 110 participants provided data for the entire period of the study. Methods: An experience-sampling methodology was used to document the symptoms reported over time. Stepwise multivariate linear mixed-effects modeling was performed to identify the predictors contributing to the serially reported symptoms. Independent Variables: Independent variables considered were gender, time of the day, location, primary activity, and type of interactant (person) of the participant, physical activity status, trouble sleeping, alcohol consumption, caffeine consumption, stress, anxiety, depression, mental and physical fatigue, and life stressors. Main Outcome Measures: The key outcome measures were the change in total symptom score (TSS change ) and symptom severity score (SSS change ) reported over 7 consecutive days. Results: The predictors of location at the time of reporting, physical fatigue (estimate: -0.98, P < 001) and mental fatigue (estimate: -0.53, P < 001) contributed to the TSS change . Post hoc analysis of the variable of location at the time of reporting revealed that participants reported increased TSS change when they were at a café/restaurant compared to a flat/college or university. Conclusions: A number of factors within the context of daily life influenced the postconcussion-like symptoms reported over time. These findings indicate that clinicians need to be cautious when interpreting the serially assessed symptom scores to track the recovery profile of a concussed athlete to make decisions on return-to-play. Additional investigation is warranted to examine the change in symptom scores reported over time by concussed individuals, considering that this study was conducted in a nonconcussed cohort. Level of Evidence: To be determined. © 2017 American Academy of Physical Medicine and Rehabilitation.