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.