Subjective social status predicts in vivo responsiveness of β-adrenergic receptors.

OBJECTIVE

Several poor health outcomes, including cardiovascular risk, have been associated with both subjective social status (SSS) and sympathetic overactivity. Because prolonged sympathetic overactivation down regulates beta adrenergic receptor (β-AR) function, reduced β-AR responsiveness is considered an indicator of sympathetic overactivity and a cardiovascular risk factor. Though prior research has focused on objective social status and β-AR function, no studies have examined the association between SSS and β-AR function. We aimed to learn whether SSS predicts the in vivo responsiveness of β-ARs.

METHODS

We assessed the chronotropic 25 dose (CD25), an in vivo marker of β-AR responsiveness, in 94 healthy participants. The MacArthur scales of subjective social status were used to assess SSS in the U.S.A. (SSS-USA) and in the local community (SSS-C). Objective social status was analyzed by calculating the Hollingshead two-factor index.

RESULTS

β-AR responsiveness was reduced (as indicated by higher CD25 values) in participants with lower SSS-USA (p = .007) and lower SSS-C (p < .001). The relationship between CD25 and SSS was particularly robust with respect to SSS-C. Hierarchical regression analyses revealed that SSS-C remained a significant predictor of CD25 (p < .001) and accounted for 14% of the total variance (32%) in CD25 after adjusting for sociodemographic variables (age, ethnicity, gender), health factors (exercise, smoking status, body mass index) and objective social status.

CONCLUSION

Our results indicate that β-AR function may be an important component of the link between SSS and health.