Would the Actigraph Always be Sufficient for Sleep Analysis in Exercise-Based Studies? A Case Report of Negative Response of Sleep to Exercise

Introduction Sleep deprivation is common after coronary artery bypass grafting (CABG). It is mostly managed well by exercise. The number of reported post-CABG cases that respond negatively to exercise is scanty. The etiology is usually associated with the underlying sleep pathology, and how it responds to exercise. Cases with undiagnosed central sleep apnea post CABG have not been reported before. Case description A medically stable male patient, 63 years old, hypertensive, but not diabetic, had entered coronary artery bypass grafting (CABG) 8 weeks before attending the outpatient cardiac rehabilitation unit and was referred for a cardiac rehabilitation program at this time. He entered a study in the cardiac rehabilitation center utilizing either aerobic or combined aerobic and resistance training for 10 weeks to improve sleep architecture and functional capacity post-CABG. After randomization, he entered the group doing combined aerobic and resistance exercises. All of the patients in this group improved except him, his sleep quality worsened, but his functional capacity improved. After a complete analysis of sleep on polysomnography, it was revealed that the patient had central sleep apnea that was mostly worsened by resistance training. The patient was withdrawn from the study by the 8th week, and his sleep condition improved gradually. After then, he was asked to attend the cardiac rehabilitation center again to share in aerobic exercise, having evidence that central sleep apnea does not respond negatively to this form of training. After 12 months of follow-up, the patient still shows no signs of sleep deprivation. Conclusion Sleep deprivation is prevalent in post-CABG patients, but with different presentations and it can generally improve by exercise. Identification of the underlying cause of the sleeping difficulty is a cornerstone of targeted treatment.