Already common practice in the U.S. for a long time, studies on the relationship between subjective social status (SSS) and health are somewhat hesitantly slow in coming in the German-speaking parts of the world. Even as late as November 2010, Ruth Hegar and Andreas Mielck of the Helmholtz-Center Munich found no single study done in the German language which was put together on the topic “subjective social status and health.”
Frank Eutenheuer (Philipps University Marburg) and Paul J. Mills (University of California, USA) et al. have now shown in their current study that a social status which is subjectively perceived as low can seemingly down-regulate the beta-adrenergic receptors in-vivo. Down-regulated beta receptors are viewed as signs of sustained sympathetic overactivity; this in turn is associated with an increased cardiovascular risk.
The researchers studied 94 healthy study participants. They were to assess their own status using the MacArthur Scale for Subjective Social Status. The MacArthur Scale (SSS) is the standard instrument used for the mapping of this societal characteristic. The idea here is to present a picture of a ten-rung ladder on which the study participants draw a cross at the level on which they think that they stand.
The rungs of the social ladder
Study participants were supposed to put crosses on two different ladders: once on a ladder, which relates to their social status in the United States as a whole (USA SSS) and once on a ladder, in which case they refer to their social status in local terms (SSS-C, C = community). It is interesting here that there definitely can be differences: a participant may, for example, within the national picture settle in relatively low on the social ladder, because he or she has little education and a low income. Locally the person may feel, however, that he or she stands in a position relatively well above that, because he or she, for example, is a notable member within the local faith community or sports club. The objective status of the participants was assessed using the Hollingshead Two-Factor Index which inquires into the status of profession and education.
In capturing the sensitivity of beta-adrenergic receptors, the authors used the so-called “chronotropic dose 25” – abbreviated CD25 – as a marker. In this study, the beta-adrenergic agonist isoproterenol was infused into the participants. Analysis was then made, as to which amount was needed to increase the heart rate by 25 beats per minute. The lower the beta-receptor sensitivity, the higher the dose of isoproterenol needed. It was shown that sensitivity of the beta-receptors in participants with low subjective social status was significantly reduced (SSS U.S.: p = 0.007, SSS-C: p < 0.001). Even after adjusting the data for socio-demographic variables (age, ethnicity, gender), health (exercise, smoking/non-smoking, body mass index) and objective social status, the SSS-C was still a significant predictor of beta-receptor sensitivity.
The authors conclude from this that the beta-adrenoreceptor function represents a critical link between subjective social status and health.