 This study found that people who are at higher risk of obstructive sleep apnea, OSA, are more likely to experience poorer mental health, lower health-related quality of life, HRQOL, and increased multi-morbidity compared to those with low OSA risk. Additionally, OSA was associated with decreased performance on all items of the Eurocol 5 dimensions, EQ, 5D, and health-related quality of life instrument with eight items, hint, eight, scales. These findings suggest that OSA may contribute to poorer mental health, HRQOL, and multi-morbidity. This article was authored by Miri Lee and Sung Min Young.