The researchers found that among women whose income was lower than their male counterparts, the odds of major depression were nearly 2.5 times higher than men; but the odds of depression among women whose income equalled or exceeded their male counterparts was no different than men.
Results were similar for generalised anxiety disorder. Overall, women's odds of past-year anxiety were more than 2.5 times higher than men's.
For women whose income equalled or exceeded their male counterparts, their odds of anxiety disorder were greatly decreased.
The findings are based on data from a 2001-2002 US population-representative sample of 22,581 working adults ages 30-65.
"Our results show that some of the gender disparities in depression and anxiety may be due to the effects of structural gender inequality in the workforce and beyond," said first author Jonathan Platt, a PhD student at Columbia University.
"The social processes that sort women into certain jobs, compensate them less than equivalent male counterparts, and create gender disparities in domestic labour have material and psychosocial consequences," said Platt.
As examples, the researchers refer to the norms, expectations, and opportunities surrounding the types of jobs women occupy and the way those jobs are valued and compensated relative to men.
"If women internalise these negative experiences as reflective of inferior merit, rather than the result of discrimination, they may be at increased risk for depression and anxiety disorders," said Platt.
"Our findings suggest that policies must go beyond prohibiting overt gender discrimination like sexual harassment," said Katherine Keyes, from Columbia University.
The study was published in the journal Social Science and Medicine.
