The differential effects of sleep quality and quantity on the relationship between SES and health.

Although socioeconomic status (SES) has long been recognized as a principal determinant of health, one factor yet to be considered in the context of SES and health is the role of sleep. Individuals of lower socioeconomic status have been found more likely to experience sleep disorders, 1 and sleep disturbances have been associated with poorer health. 2 The amount of sleep people get has been found to mediate the relationship between stress-related intrusive thoughts and natural killer cell levels. 3 However, sleep has yet to be examined as a potential mediator of the impact of socioeconomic status on physical or mental health. This study tested the following three hypotheses. First, participants of higher socioeconomic status will report better psychological health. Second, participants of higher socioeconomic status will report better physical health. Third, the relationship between participants’ socioeconomic status and their health will be mediated by either their quantity or quality of sleep.