Socioeconomic variation in the impact of obesity on health-related quality of life.

There is evidence that obesity has a negative impact on health-related quality of life (HRQL). However, little attention has been paid to variations in this impact between population groups. This study investigates the relationship between HRQL and obesity, and whether or not this relationship varies by socioeconomic status (SES). Data were taken from four rounds of the Health Survey for England (2003-2006; n = 33,716) for persons aged 16 and above. Banded total annual household income is regressed against a comprehensive set of SES indicators using interval regression. We use the equivalised predicted values from this model, categorised into quartiles, as our measure of SES. We regress EQ-5D scores against interactions between body mass index and SES categories. Obesity is negatively correlated with HRQL. The negative impact of obesity is greater in people from lower SES groups. Overweight and obese people in lower SES groups have lower HRQL than those of normal weight in the same SES group, and have lower HRQL than those in higher SES groups of the same weight. This trend is also observed after controlling for individual and household characteristics, although the statistical significance and magnitude of effects is diminished.