The effect of subjective and objective social class on health-related quality of life: new paradigm using longitudinal analysis

BACKGROUND: To investigate the impact of the gap between subjective and objective social status on health-related quality of life. METHODS: We analyzed data from 12,350 participants aged ≥18 years in the Korean Health Panel Survey. Health-related quality of life was measured by EuroQol-Visual analogue scale. Objective (income and education) and subjective social class (measured by MacArthur scale) was classified into three groups (High, Middle, Low). In terms of a gap between objective and subjective social class, social class was grouped into nine categories ranging from High–High to Low–Low. A linear mixed model was used to investigate the association between the combined social class and health-related quality of life. RESULTS: The impact of the gap between objective and subjective status on Health-related quality of life varied according to the type of gap. Namely, at any given subjective social class, an individual’s quality of life declined with a decrease in the objective social class. At any given objective social class (e.g., HH, HM, HL; in terms of both education and income), an individual’s quality of life declined with a one-level decrease in subjective social class. CONCLUSION: Our results suggest that studies of the relationship between social class and health outcomes may consider the multidimensional nature of social status. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12955-015-0319-0) contains supplementary material, which is available to authorized users.