• Top
• Background
• Methods
• Results
• Conclusion

Background

Socioeconomic factors are inversely associated with cardiovascular disease morbity and mortality. The underlying biological mechanisms, however, that mediate this relationship are largely unknown.

Methods

We investigated the relationship between several indicators of social class and C-reactive protein [CRP] in two different population-based cross-sectional samples. The first sample (MONICA Augsburg Survey 1994/95) comprised 2293 men and 2203 women aged 25-74 years, the second 854 men and 1134 women aged 18-89 years who participated in a national health study representative of the former West-Germany during 1987/88 (VERA). In MONICA, formal years of schooling—a robust indicator of social status in Germany—was used. Three socioeconomic indices (education years, occupational status, and overall household income) and a score combining these indicators were used to assess social class in VERA. CRP measurements were done by an high-sensitivity immunoradiometric assay (range 0.05-10 mg/L). Crude geometric mean levels of CRP were calculated among categories of social class using a general linear regression model first and then, after adjustment for age, sex, smoking status, body mass index, physical activity and HDL-cholesterol.

Results

Higher social status was consistently associated with lower levels of CRP in both samples. There appeared to be a linear inverse relationship between CRP and the combined score in VERA. In the fully adjusted model the difference between the upper and the bottom category remained significant for education years in MONICA and for household income in VERA. For the other indices, a trend towards lower CRP concentrations among categories reflecting higher social status was observed,which, however was no longer statistically significant.

Conclusion

Appreciable differences in plasma CRP levels were found between several indicators of social class in two different representative population-based samples even after adjustment for a variety of potential confounders. Since CRP represents an established cardiovascular risk factor, this association might represent a link between low social status and increased cardiovascular and all-cause morbidity and mortality.

Have something to say? Post a comment on this article!