Research has found that people with access to tertiary-care centres are less likely to be affected by depressive symptoms.
Published in the journal Arthritis Care and Research, the study looked at the effects of a low socioeconomic position on the depressive symptoms of people with rheumatoid arthritis (RA).
The report compared patients from an urban county, public hospital that serves the poor with a referral, tertiary-care medical centre.
Around 37 per cent of the study's participants were diagnosed with moderate to severe depression; comparable with previous studies that have placed occurrence at between 13 and 42 per cent of patients.
However, those from the tertiary-care centre were less likely to show any symptoms of depression.
Dr Mary Margaretten from the Arthritis Research Group at the University of California commented: "For the same level of disability, patients with low socioeconomic status may be more likely to experience depression.
"Detection and documentation of the differing effects of disability on depression between patients of different socioeconomic status can help rheumatologists improve health outcomes by initiating appropriate and timely treatment for depression."