Self-reported chronic conditions and EQ-5D index scores in the US adult population

Objective: To examine the unique health-related quality of life ( HRQoL) decrements associated with common chronic conditions in the general US adult population. Methods: Data were obtained from a study aimed at establishing a US population-based set of preference weights for the health states defined by the EQ-5D. The EQ-5D is a brief, self-completed instrument for describing and valuing HRQoL. As part of that study, along with the EQ-5D items, data regarding socio-demographic characteristics and chronic medical conditions were collected. The EQ-5D has five dimensions, from which an index score can be calculated that falls on a scale where 0.0 = death and 1.0 = perfect health. Ordinary least squares regression models were conducted using the EQ-5D index score as the dependent variable to estimate the association between each chronic condition and the index score after adjusting for socio-demographic variables. The population sampling weights were applied in the analyses to adjust for the over-sampling of the minority groups. Results: Approximately three-fifths ( 62.5%) of the study sample reported having at least one of the 18 chronic medical conditions; sinusitis ( 24.8%), hypertension ( 23.5%), and arthritis ( 21.5%) were the most commonly reported conditions. The chronic conditions that had the greatest negative association with EQ-5D index scores were depression and arthritis. Conclusion: Unique associations were found between several chronic conditions and HRQoL after accounting for the presence of other conditions and socio-demographic characteristics. The results of this study provide an indication of the relative HRQoL decrements associated with various chronic conditions in the general US adult population. The major limitation of this analysis is the uncertainty of the causal relationship between chronic conditions and HRQoL due to the cross-sectional nature of the study data. In addition, because it was unknown how well the conditions were managed, caution is needed in interpreting study results regarding the relative impact of chronic conditions on HRQoL.