Objective versus Subjective Cognitive Functioning in Patients with Obstructive Sleep Apnea

Study objectives: Previous studies have found that patients' neurocognitive functions were affected by OSA symptoms. However, no study has focused on the subjective awareness of cognitive impairments. This study used a sub- jective rating scale to evaluate OSA patient perceptions of their cognitive impairments, and explore the relationship be- tween subjective and objective cognitive functions. Methods: An independent-group design was used to compare objective and subjective cognitive performance in both the OSA and control groups. An experimental group of 19 male OSA patients and a control group of 19 normal subjects matched in age and education participated in the study. A neurocognitive test battery that measures attention, memory and executive functions, and the SCIRS (Subjective Cognitive Impairment Rating Scale) that measures subjective perception of cognitive impairments were used. Results: On the neurocognitive test measures, OSA patients demonstrated decreased performance on memory and execu- tive function. On the subjective measures, OSA patients reported a mild to moderately negative impact on attention, memory, and emotional control due to OSA. Conclusions: The results show that OSA patients may not be fully aware of their cognitive impairments, especially with regard to their executive functions. The inconsistency suggests that including neurocognitive tests in the evaluation of sleep-related breathing disorders may provide useful information that cannot be obtained through clinical interviews.